,,elements ,,of ,,chemistry1 ,,in ,a ,,new ,,systematic ,,order1 ,,containing ,,all ,,the ,,modern ,,discoveries4 ,,illustrated ,,with ,,thirteen ,,copperplates4 ,,by ,,mr ,,lavoisier1 ,member of the ,academy of ,sciences1 ,royal ,society of ,medicine1 and ,agricultural ,society of ,paris1 of the ,royal ,society of ,london1 and ,philosophical ,societies of ,orleans1 ,bologna1 ,basil1 ,philadelphia1 ,haerlem1 ,manchester1 c4 c4 ,,translated ,,from ,,the ,,french1 ,,by ,,robert ,,kerr1 ,f4,r4 ,a4,,ss4,e4 ,member of the ,royal ,college of ,surgeons1 and ,surgeon to the ,orphan ,hospital of ,edinburgh4 ,,edinburgh3 ,,printed ,,for ,,william ,,creech1 ,,and ,,sold ,,in ,,london ,,by ,g4 ,g4 ,,and ,j4 ,j4 ,,robinsons4 ,,mdccxc4 9999999999999999999999999999999999999999 9999999999999999999999999999999999999999 9999999999999999999999999999999999999999 999999999999999999999999 ,transcriber's note3 ,tables needed to be split to fit space constraints4 ,minor typos have been corrected and footnotes moved to the end of the chapters4 ,the italic markup for single italized letters 7such as variables in equations7 and weight abbreviations are deleted for easier reading4 9999999999999999999999999999999999999999 9999999999999999999999999999999999999999 9999999999999999999999999999999999999999 999999999999999999999999 ,,advertisement ,,of ,,the ,,translator4 ,the very high character of ,mr ,lavoisier as a chemical philosopher1 and the great revolution which1 in the opinion of many excellent chemists1 he has effected in the theory of chemistry1 has long made it much desired to have a connected account of his discoveries1 and of the new theory he has founded upon the modern experiments written by himself4 ,this is now accomplished by the publication of his ,elements of ,chemistry2 therefore no excuse can be at all necessary for giving the following work to the public in an ,english dress2 and the only hesitation of the ,translator is with regard to his own abilities for the task4 ,he is most ready to confess1 that his knowledge of the composition of language fit for publication is far inferior to his attachment to the subject1 and to his desire of appearing decently before the judgment of the world4 ,he has earnestly endeavoured to give the meaning of the ,author with the most scrupulous fidelity1 having paid infinitely greater attention to accuracy of translation than to elegance of stile4 ,this last indeed1 had he even1 by proper labour1 been capable of attaining1 he has been obliged1 for very obvious reasons1 to neglect1 far more than accorded with his wishes4 ,the ,french copy did not reach his hands before the middle of ,september2 and it was judged necessary by the ,publisher that the ,translation should be ready by the commencement of the ,university ,session at the end of ,october4 ,he at first intended to have changed all the weights and measures used by ,mr ,lavoisier into their correspondent ,english denominations1 but1 upon trial1 the task was found infinitely too great for the time allowed2 and to have executed this part of the work inaccurately1 must have been both useless and misleading to the reader4 ,all that has been attempted in this way is adding1 between brackets 7 71 the degrees of ,fahrenheit's scale corresponding with those of ,reaumeur's thermometer1 which is used by the ,author4 ,rules are added1 however1 in the ,appendix1 for converting the ,french weights and measures into ,english1 by which means the reader may at any time calculate such quantities as occur1 when desirous of comparing ,mr ,lavoisier's experiments with those of ,british authors4 ,by an oversight1 the first part of the translation went to press without any distinction being preserved between charcoal and its simple elementary part1 which enters into chemical combinations1 especially with oxygen or the acidifying principle1 forming carbonic acid4 ,this pure element1 which exists in great plenty in well made charcoal1 is named by ,mr ,lavoisier carbone1 and ought to have been so in the translation2 but the attentive reader can very easily rectify the mistake4 ,there is an error in ,plate ,,xi4 which the engraver copied strictly from the original1 and which was not discovered until the plate was worked off at press1 when that part of the ,elements which treats of the apparatus there represented came to be translated4 ,the two tubes #ba4 and #bd4 by which the gas is conveyed into the bottles of alkaline solution #bb4 #be4 should have been made to dip into the liquor1 while the other tubes #bc4 and #bf4 which carry off the gas1 ought to have been cut off some way above the surface of the liquor in the bottles4 ,a few explanatory notes are added2 and indeed1 from the perspicuity of the ,author1 very few were found necessary4 ,in a very small number of places1 the liberty has been taken of throwing to the bottom of the page1 in notes1 some parenthetical expressions1 only relative to the subject1 which1 in their original place1 tended to confuse the sense4 ,these1 and the original notes of the ,author1 are distinguished by the letter ,a1 and to the few which the ,translator has ventured to add1 the letter ,e is subjoined4 ,mr ,lavoisier has added1 in an ,appendix1 several very useful ,tables for facilitating the calculations now necessary in the advanced state of modern chemistry1 wherein the most scrupulous accuracy is required4 ,it is proper to give some account of these1 and of the reasons for omitting several of them4 ,no4 ,i4 of the ,french ,appendix is a ,table for converting ounces1 gros1 and grains1 into the decimal fractions of the ,french pound2 and ,no4 ,,ii4 for reducing these decimal fractions again into the vulgar subdivisions4 ,no4 ,,iii4 contains the number of ,french cubical inches and decimals which correspond to a determinate weight of water4 ,the ,translator would most readily have converted these ,tables into ,english weights and measures2 but the necessary calculations must have occupied a great deal more time than could have been spared in the period limited for publication4 ,they are therefore omitted1 as altogether useless1 in their present state1 to the ,british chemist4 ,no4 ,,iv4 is a ,table for converting lines or twelfth parts of the inch1 and twelfth parts of lines1 into decimal fractions1 chiefly for the purpose of making the necessary corrections upon the quantities of gasses according to their barometrical pressure4 ,this can hardly be at all useful or necessary1 as the barometers used in ,britain are graduated in decimal fractions of the inch1 but1 being referred to by the ,author in the text1 it has been retained1 and is ,no4 ,i4 of the ,appendix to this ,translation4 ,no4 ,v4 ,is a ,table for converting the observed heights of water within the jars used in pneumato-chemical experiments into correspondent heights of mercury for correcting the volume of gasses4 ,this1 in ,mr ,lavoisier's ,work1 is expressed for the water in lines1 and for the mercury in decimals of the inch1 and consequently1 for the reasons given respecting the ,fourth ,table1 must have been of no use4 ,the ,translator has therefore calculated a ,table for this correction1 in which the water is expressed in decimals1 as well as the mercury4 ,this ,table is ,no4 ,,ii4 of the ,english ,appendix4 ,no4 ,,vi4 contains the number of ,french cubical inches and decimals contained in the corresponding ounce-measures used in the experiments of our celebrated countryman ,dr ,priestley4 ,this ,table1 which forms ,no4 ,,iii4 of the ,english ,appendix1 is retained1 with the addition of a column1 in which the corresponding ,english cubical inches and decimals are expressed4 ,no4 ,,vii4 ,is a ,table of the weights of a cubical foot and inch1 ,french measure1 of the different gasses expressed in ,french ounces1 gros1 grains1 and decimals4 ,this1 which forms ,no4 ,,vi4 of the ,english ,appendix1 has been1 with considerable labour1 calculated into ,english weight and measure4 ,no4 ,,viii4 ,gives the specific gravities of a great number of bodies1 with columns1 containing the weights of a cubical foot and inch1 ,french measure1 of all the substances4 ,the specific gravities of this ,table1 which is ,no4 ,,vii4 of the ,english ,appendix1 are retained1 but the additional columns1 as useless to the ,british philosopher1 are omitted2 and to have converted these into ,english denominations must have required very long and painful calculations4 ,rules are subjoined1 in the ,appendix to this translation1 for converting all the weights and measures used by ,mr ,lavoisier into corresponding ,english denominations2 and the ,translator is proud to acknowledge his obligation to the learned ,professor of ,natural ,philosophy in the ,university of ,edinburgh1 who kindly supplied him with the necessary information for this purpose4 ,a ,table is likewise added1 ,no4 ,,iv4 of the ,english ,appendix1 for converting the degrees of ,reaumeur's scale used by ,mr ,lavoisier into the corresponding degrees of ,fahrenheit1 which is universally employed in ,britain#a4 ,this ,translation is sent into the world with the utmost diffidence1 tempered1 however1 with this consolation1 that1 though it must fall greatly short of the elegance1 or even propriety of language1 which every writer ought to endeavour to attain1 it cannot fail of advancing the interests of true chemical science1 by disseminating the accurate mode of analysis adopted by its justly celebrated ,author4 ,should the public call for a second edition1 every care shall be taken to correct the forced imperfections of the present translation1 and to improve the work by valuable additional matter from other authors of reputation in the several subjects treated of4 ,,edinburgh1 ,oct4 #bc4 #aghi4 ,,footnotes3 #a ,the ,translator has since been enabled1 by the kind assistance of the gentleman above alluded to1 to give ,tables1 of the same nature with those of ,mr ,lavoisier1 for facilitating the calculations of the results of chemical experiments4 ,,preface ,,of ,,the ,,author4 ,when ,i began the following ,work1 my only object was to extend and explain more fully the ,memoir which ,i read at the public meeting of the ,academy of ,sciences in the month of ,april #aghg1 on the necessity of reforming and completing the ,nomenclature of ,chemistry4 ,while engaged in this employment1 ,i perceived1 better than ,i had ever done before1 the justice of the following maxims of the ,abb de ,condillac1 in his ,system of ,logic1 and some other of his works4 ,we think only through the medium of words4--,languages are true analytical methods4--,algebra1 which is adapted to its purpose in every species of expression1 in the most simple1 most exact1 and best manner possible1 is at the same time a language and an analytical method4--,the art of reasoning is nothing more than a language well arranged4 ,thus1 while ,i thought myself employed only in forming a ,nomenclature1 and while ,i proposed to myself nothing more than to improve the chemical language1 my work transformed itself by degrees1 without my being able to prevent it1 into a treatise upon the ,elements of ,chemistry4 ,the impossibility of separating the nomenclature of a science from the science itself1 is owing to this1 that every branch of physical science must consist of three things2 the series of facts which are the objects of the science1 the ideas which represent these facts1 and the words by which these ideas are expressed4 ,like three impressions of the same seal1 the word ought to produce the idea1 and the idea to be a picture of the fact4 ,and1 as ideas are preserved and communicated by means of words1 it necessarily follows that we cannot improve the language of any science without at the same time improving the science itself2 neither can we1 on the other hand1 improve a science1 without improving the language or nomenclature which belongs to it4 ,however certain the facts of any science may be1 and1 however just the ideas we may have formed of these facts1 we can only communicate false impressions to others1 while we want words by which these may be properly expressed4 ,to those who will consider it with attention1 the first part of this treatise will afford frequent proofs of the truth of the above observations4 ,but as1 in the conduct of my work1 ,i have been obliged to observe an order of arrangement essentially differing from what has been adopted in any other chemical work yet published1 it is proper that ,i should explain the motives which have led me to do so4 ,it is a maxim universally admitted in geometry1 and indeed in every branch of knowledge1 that1 in the progress of investigation1 we should proceed from known facts to what is unknown4 ,in early infancy1 our ideas spring from our wants2 the sensation of want excites the idea of the object by which it is to be gratified4 ,in this manner1 from a series of sensations1 observations1 and analyses1 a successive train of ideas arises1 so linked together1 that an attentive observer may trace back to a certain point the order and connection of the whole sum of human knowledge4 ,when we begin the study of any science1 we are in a situation1 respecting that science1 similar to that of children2 and the course by which we have to advance is precisely the same which ,nature follows in the formation of their ideas4 ,in a child1 the idea is merely an effect produced by a sensation2 and1 in the same manner1 in commencing the study of a physical science1 we ought to form no idea but what is a necessary consequence1 and immediate effect1 of an experiment or observation4 ,besides1 he that enters upon the career of science1 is in a less advantageous situation than a child who is acquiring his first ideas4 ,to the child1 ,nature gives various means of rectifying any mistakes he may commit respecting the salutary or hurtful qualities of the objects which surround him4 ,on every occasion his judgments are corrected by experience2 want and pain are the necessary consequences arising from false judgment2 gratification and pleasure are produced by judging aright4 ,under such masters1 we cannot fail to become well informed2 and we soon learn to reason justly1 when want and pain are the necessary consequences of a contrary conduct4 ,in the study and practice of the sciences it is quite different2 the false judgments we form neither affect our existence nor our welfare2 and we are not forced by any physical necessity to correct them4 ,imagination1 on the contrary1 which is ever wandering beyond the bounds of truth1 joined to self-love and that self-confidence we are so apt to indulge1 prompt us to draw conclusions which are not immediately derived from facts2 so that we become in some measure interested in deceiving ourselves4 ,hence it is by no means to be wondered1 that1 in the science of physics in general1 men have often made suppositions1 instead of forming conclusions4 ,these suppositions1 handed down from one age to another1 acquire additional weight from the authorities by which they are supported1 till at last they are received1 even by men of genius1 as fundamental truths4 ,the only method of preventing such errors from taking place1 and of correcting them when formed1 is to restrain and simplify our reasoning as much as possible4 ,this depends entirely upon ourselves1 and the neglect of it is the only source of our mistakes4 ,we must trust to nothing but facts3 ,these are presented to us by ,nature1 and cannot deceive4 ,we ought1 in every instance1 to submit our reasoning to the test of experiment1 and never to search for truth but by the natural road of experiment and observation4 ,thus mathematicians obtain the solution of a problem by the mere arrangement of data1 and by reducing their reasoning to such simple steps1 to conclusions so very obvious1 as never to lose sight of the evidence which guides them4 ,thoroughly convinced of these truths1 ,i have imposed upon myself1 as a law1 never to advance but from what is known to what is unknown2 never to form any conclusion which is not an immediate consequence necessarily flowing from observation and experiment2 and always to arrange the facts1 and the conclusions which are drawn from them1 in such an order as shall render it most easy for beginners in the study of chemistry thoroughly to understand them4 ,hence ,i have been obliged to depart from the usual order of courses of lectures and of treatises upon chemistry1 which always assume the first principles of the science1 as known1 when the pupil or the reader should never be supposed to know them till they have been explained in subsequent lessons4 ,in almost every instance1 these begin by treating of the elements of matter1 and by explaining the table of affinities1 without considering1 that1 in so doing1 they must bring the principal phenomena of chemistry into view at the very outset3 ,they make use of terms which have not been defined1 and suppose the science to be understood by the very persons they are only beginning to teach4 ,it ought likewise to be considered1 that very little of chemistry can be learned in a first course1 which is hardly sufficient to make the language of the science familiar to the ears1 or the apparatus familiar to the eyes4 ,it is almost impossible to become a chemist in less than three or four years of constant application4 ,these inconveniencies are occasioned not so much by the nature of the subject1 as by the method of teaching it2 and1 to avoid them1 ,i was chiefly induced to adopt a new arrangement of chemistry1 which appeared to me more consonant to the order of ,nature4 ,i acknowledge1 however1 that in thus endeavouring to avoid difficulties of one kind1 ,i have found myself involved in others of a different species1 some of which ,i have not been able to remove2 but ,i am persuaded1 that such as remain do not arise from the nature of the order ,i have adopted1 but are rather consequences of the imperfection under which chemistry still labours4 ,this science still has many chasms1 which interrupt the series of facts1 and often render it extremely difficult to reconcile them with each other3 ,it has not1 like the elements of geometry1 the advantage of being a complete science1 the parts of which are all closely connected together3 ,its actual progress1 however1 is so rapid1 and the facts1 under the modern doctrine1 have assumed so happy an arrangement1 that we have ground to hope1 even in our own times1 to see it approach near to the highest state of perfection of which it is susceptible4 ,the rigorous law from which ,i have never deviated1 of forming no conclusions which are not fully warranted by experiment1 and of never supplying the absence of facts1 has prevented me from comprehending in this work the branch of chemistry which treats of affinities1 although it is perhaps the best calculated of any part of chemistry for being reduced into a completely systematic body4 ,messrs ,geoffroy1 ,gellert1 ,bergman1 ,scheele1 ,de ,morveau1 ,kirwan1 and many others1 have collected a number of particular facts upon this subject1 which only wait for a proper arrangement2 but the principal data are still wanting1 or1 at least1 those we have are either not sufficiently defined1 or not sufficiently proved1 to become the foundation upon which to build so very important a branch of chemistry4 ,this science of affinities1 or elective attractions1 holds the same place with regard to the other branches of chemistry1 as the higher or transcendental geometry does with respect to the simpler and elementary part2 and ,i thought it improper to involve those simple and plain elements1 which ,i flatter myself the greatest part of my readers will easily understand1 in the obscurities and difficulties which still attend that other very useful and necessary branch of chemical science4 ,perhaps a sentiment of self-love may1 without my perceiving it1 have given additional force to these reflections4 ,mr de ,morveau is at present engaged in publishing the article ,affinity in the ,methodical ,encyclopdia2 and ,i had more reasons than one to decline entering upon a work in which he is employed4 ,it will1 no doubt1 be a matter of surprise1 that in a treatise upon the elements of chemistry1 there should be no chapter on the constituent and elementary parts of matter2 but ,i shall take occasion1 in this place1 to remark1 that the fondness for reducing all the bodies in nature to three or four elements1 proceeds from a prejudice which has descended to us from the ,greek ,philosophers4 ,the notion of four elements1 which1 by the variety of their proportions1 compose all the known substances in nature1 is a mere hypothesis1 assumed long before the first principles of experimental philosophy or of chemistry had any existence4 ,in those days1 without possessing facts1 they framed systems2 while we1 who have collected facts1 seem determined to reject them1 when they do not agree with our prejudices4 ,the authority of these fathers of human philosophy still carry great weight1 and there is reason to fear that it will even bear hard upon generations yet to come4 ,it is very remarkable1 that1 notwithstanding of the number of philosophical chemists who have supported the doctrine of the four elements1 there is not one who has not been led by the evidence of facts to admit a greater number of elements into their theory4 ,the first chemists that wrote after the revival of letters1 considered sulphur and salt as elementary substances entering into the composition of a great number of substances2 hence1 instead of four1 they admitted the existence of six elements4 ,beccher assumes the existence of three kinds of earth1 from the combination of which1 in different proportions1 he supposed all the varieties of metallic substances to be produced4 ,stahl gave a new modification to this system2 and succeeding chemists have taken the liberty to make or to imagine changes and additions of a similar nature4 ,all these chemists were carried along by the influence of the genius of the age in which they lived1 which contented itself with assertions without proofs2 or1 at least1 often admitted as proofs the slighted degrees of probability1 unsupported by that strictly rigorous analysis required by modern philosophy4 ,all that can be said upon the number and nature of elements is1 in my opinion1 confined to discussions entirely of a metaphysical nature4 ,the subject only furnishes us with indefinite problems1 which may be solved in a thousand different ways1 not one of which1 in all probability1 is consistent with nature4 ,i shall therefore only add upon this subject1 that if1 by the term elements1 we mean to express those simple and indivisible atoms of which matter is composed1 it is extremely probable we know nothing at all about them2 but1 if we apply the term elements1 or principles of bodies1 to express our idea of the last point which analysis is capable of reaching1 we must admit1 as elements1 all the substances into which we are capable1 by any means1 to reduce bodies by decomposition4 ,not that we are entitled to affirm1 that these substances we consider as simple may not be compounded of two1 or even of a greater number of principles2 but1 since these principles cannot be separated1 or rather since we have not hitherto discovered the means of separating them1 they act with regard to us as simple substances1 and we ought never to suppose them compounded until experiment and observation has proved them to be so4 ,the foregoing reflections upon the progress of chemical ideas naturally apply to the words by which these ideas are to be expressed4 ,guided by the work which1 in the year #aghg1 ,messrs de ,morveau1 ,berthollet1 de ,fourcroy1 and ,i composed upon the ,nomenclature of ,chemistry1 ,i have endeavoured1 as much as possible1 to denominate simple bodies by simple terms1 and ,i was naturally led to name these first4 ,it will be recollected1 that we were obliged to retain that name of any substance by which it had been long known in the world1 and that in two cases only we took the liberty of making alterations2 first1 in the case of those which were but newly discovered1 and had not yet obtained names1 or at least which had been known but for a short time1 and the names of which had not yet received the sanction of the public2 and1 secondly1 when the names which had been adopted1 whether by the ancients or the moderns1 appeared to us to express evidently false ideas1 when they confounded the substances1 to which they were applied1 with others possessed of different1 or perhaps opposite qualities4 ,we made no scruple1 in this case1 of substituting other names in their room1 and the greatest number of these were borrowed from the ,greek language4 ,we endeavoured to frame them in such a manner as to express the most general and the most characteristic quality of the substances2 and this was attended with the additional advantage both of assisting the memory of beginners1 who find it difficult to remember a new word which has no meaning1 and of accustoming them early to admit no word without connecting with it some determinate idea4 ,to those bodies which are formed by the union of several simple substances we gave new names1 compounded in such a manner as the nature of the substances directed2 but1 as the number of double combinations is already very considerable1 the only method by which we could avoid confusion1 was to divide them into classes4 ,in the natural order of ideas1 the name of the class or genus is that which expresses a quality common to a great number of individuals3 ,the name of the species1 on the contrary1 expresses a quality peculiar to certain individuals only4 ,these distinctions are not1 as some may imagine1 merely metaphysical1 but are established by ,nature4 ,a child1 says the ,abb de ,condillac1 is taught to give the name tree to the first one which is pointed out to him4 ,the next one he sees presents the same idea1 and he gives it the same name4 ,this he does likewise to a third and a fourth1 till at last the word tree1 which he first applied to an individual1 comes to be employed by him as the name of a class or a genus1 an abstract idea1 which comprehends all trees in general4 ,but1 when he learns that all trees serve not the same purpose1 that they do not all produce the same kind of fruit1 he will soon learn to distinguish them by specific and particular names4 ,this is the logic of all the sciences1 and is naturally applied to chemistry4 ,the acids1 for example1 are compounded of two substances1 of the order of those which we consider as simple2 the one constitutes acidity1 and is common to all acids1 and1 from this substance1 the name of the class or the genus ought to be taken2 the other is peculiar to each acid1 and distinguishes it from the rest1 and from this substance is to be taken the name of the species4 ,but1 in the greatest number of acids1 the two constituent elements1 the acidifying principle1 and that which it acidifies1 may exist in different proportions1 constituting all the possible points of equilibrium or of saturation4 ,this is the case in the sulphuric and the sulphurous acids2 and these two states of the same acid we have marked by varying the termination of the specific name4 ,metallic substances which have been exposed to the joint action of the air and of fire1 lose their metallic lustre1 increase in weight1 and assume an earthy appearance4 ,in this state1 like the acids1 they are compounded of a principle which is common to all1 and one which is peculiar to each4 ,in the same way1 therefore1 we have thought proper to class them under a generic name1 derived from the common principle2 for which purpose1 we adopted the term oxyd2 and we distinguish them from each other by the particular name of the metal to which each belongs4 ,combustible substances1 which in acids and metallic oxyds are a specific and particular principle1 are capable of becoming1 in their turn1 common principles of a great number of substances4 ,the sulphurous combinations have been long the only known ones in this kind4 ,now1 however1 we know1 from the experiments of ,messrs ,vandermonde1 ,monge1 and ,berthollet1 that charcoal may be combined with iron1 and perhaps with several other metals2 and that1 from this combination1 according to the proportions1 may be produced steel1 plumbago1 c4 ,we know likewise1 from the experiments of ,m4 ,pelletier1 that phosphorus may be combined with a great number of metallic substances4 ,these different combinations we have classed under generic names taken from the common substance1 with a termination which marks this analogy1 specifying them by another name taken from that substance which is proper to each4 ,the nomenclature of bodies compounded of three simple substances was attended with still greater difficulty1 not only on account of their number1 but1 particularly1 because we cannot express the nature of their constituent principles without employing more compound names4 ,in the bodies which form this class1 such as the neutral salts1 for instance1 we had to consider1 #ast1 ,the acidifying principle1 which is common to them all2 #b;d1 ,the acidifiable principle which constitutes their peculiar acid2 #c;d1 ,the saline1 earthy1 or metallic basis1 which determines the particular species of salt4 ,here we derived the name of each class of salts from the name of the acidifiable principle common to all the individuals of that class2 and distinguished each species by the name of the saline1 earthy1 or metallic basis1 which is peculiar to it4 ,a salt1 though compounded of the same three principles1 may1 nevertheless1 by the mere difference of their proportion1 be in three different states4 ,the nomenclature we have adopted would have been defective1 had it not expressed these different states2 and this we attained chiefly by changes of termination uniformly applied to the same state of the different salts4 ,in short1 we have advanced so far1 that from the name alone may be instantly found what the combustible substance is which enters into any combination2 whether that combustible substance be combined with the acidifying principle1 and in what proportion2 what is the state of the acid2 with what basis it is united2 whether the saturation be exact1 or whether the acid or the basis be in excess4 ,it may be easily supposed that it was not possible to attain all these different objects without departing1 in some instances1 from established custom1 and adopting terms which at first sight will appear uncouth and barbarous4 ,but we considered that the ear is soon habituated to new words1 especially when they are connected with a general and rational system4 ,the names1 besides1 which were formerly employed1 such as powder of algaroth1 salt of alembroth1 pompholix1 phagadenic water1 turbith mineral1 colcathar1 and many others1 were neither less barbarous nor less uncommon4 ,it required a great deal of practice1 and no small degree of memory1 to recollect the substances to which they were applied1 much more to recollect the genus of combination to which they belonged4 ,the names of oil of tartar per deliquium1 oil of vitriol1 butter of arsenic and of antimony1 flowers of zinc1 c4 were still more improper1 because they suggested false ideas3 ,for1 in the whole mineral kingdom1 and particularly in the metallic class1 there exists no such thing as butters1 oils1 or flowers2 and1 in short1 the substances to which they give these fallacious names1 are nothing less than rank poisons4 ,when we published our essay on the nomenclature of chemistry1 we were reproached for having changed the language which was spoken by our masters1 which they distinguished by their authority1 and handed down to us4 ,but those who reproach us on this account1 have forgotten that it was ,bergman and ,macquer themselves who urged us to make this reformation4 ,in a letter which the learned ,professor of ,upsal1 ,m4 ,bergman1 wrote1 a short time before he died1 to ,m4 de ,morveau1 he bids him spare no improper names2 those who are learned1 will always be learned1 and those who are ignorant will thus learn sooner4 ,there is an objection to the work which ,i am going to present to the public1 which is perhaps better founded1 that ,i have given no account of the opinion of those who have gone before me2 that ,i have stated only my own opinion1 without examining that of others4 ,by this ,i have been prevented from doing that justice to my associates1 and more especially to foreign chemists1 which ,i wished to render them4 ,but ,i beseech the reader to consider1 that1 if ,i had filled an elementary work with a multitude of quotations2 if ,i had allowed myself to enter into long dissertations on the history of the science1 and the works of those who have studied it1 ,i must have lost sight of the true object ,i had in view1 and produced a work1 the reading of which must have been extremely tiresome to beginners4 ,it is not to the history of the science1 or of the human mind1 that we are to attend in an elementary treatise3 ,our only aim ought to be ease and perspicuity1 and with the utmost care to keep every thing out of view which might draw aside the attention of the student2 it is a road which we should be continually rendering more smooth1 and from which we should endeavour to remove every obstacle which can occasion delay4 ,the sciences1 from their own nature1 present a sufficient number of difficulties1 though we add not those which are foreign to them4 ,but1 besides this1 chemists will easily perceive1 that1 in the first part of my work1 ,i make very little use of any experiments but those which were made by myself3 ,if at any time ,i have adopted1 without acknowledgment1 the experiments or the opinions of ,m4 ,berthollet1 ,m4 ,fourcroy1 ,m4 de la ,place1 ,m4 ,monge1 or1 in general1 of any of those whose principles are the same with my own1 it is owing to this circumstance1 that frequent intercourse1 and the habit of communicating our ideas1 our observations1 and our way of thinking to each other1 has established between us a sort of community of opinions1 in which it is often difficult for every one to know his own4 ,the remarks ,i have made on the order which ,i thought myself obliged to follow in the arrangement of proofs and ideas1 are to be applied only to the first part of this work4 ,it is the only one which contains the general sum of the doctrine ,i have adopted1 and to which ,i wished to give a form completely elementary4 ,the second part is composed chiefly of tables of the nomenclature of the neutral salts4 ,to these ,i have only added general explanations1 the object of which was to point out the most simple processes for obtaining the different kinds of known acids4 ,this part contains nothing which ,i can call my own1 and presents only a very short abridgment of the results of these processes1 extracted from the works of different authors4 ,in the third part1 ,i have given a description1 in detail1 of all the operations connected with modern chemistry4 ,i have long thought that a work of this kind was much wanted1 and ,i am convinced it will not be without use4 ,the method of performing experiments1 and particularly those of modern chemistry1 is not so generally known as it ought to be2 and had ,i1 in the different memoirs which ,i have presented to the ,academy1 been more particular in the detail of the manipulations of my experiments1 it is probable ,i should have made myself better understood1 and the science might have made a more rapid progress4 ,the order of the different matters contained in this third part appeared to me to be almost arbitrary2 and the only one ,i have observed was to class together1 in each of the chapters of which it is composed1 those operations which are most connected with one another4 ,i need hardly mention that this part could not be borrowed from any other work1 and that1 in the principal articles it contains1 ,i could not derive assistance from any thing but the experiments which ,i have made myself4 ,i shall conclude this preface by transcribing1 literally1 some observations of the ,abb de ,condillac1 which ,i think describe1 with a good deal of truth1 the state of chemistry at a period not far distant from our own4 ,these observations were made on a different subject2 but they will not1 on this account1 have less force1 if the application of them be thought just4 ',instead of applying observation to the things we wished to know1 we have chosen rather to imagine them4 ,advancing from one ill founded supposition to another1 we have at last bewildered ourselves amidst a multitude of errors4 ,these errors becoming prejudices1 are1 of course1 adopted as principles1 and we thus bewilder ourselves more and more4 ,the method1 too1 by which we conduct our reasonings is as absurd2 we abuse words which we do not understand1 and call this the art of reasoning4 ,when matters have been brought this length1 when errors have been thus accumulated1 there is but one remedy by which order can be restored to the faculty of thinking2 this is1 to forget all that we have learned1 to trace back our ideas to their source1 to follow the train in which they rise1 and1 as my ,lord ,bacon says1 to frame the human understanding anew4 ',this remedy becomes the more difficult in proportion as we think ourselves more learned4 ,might it not be thought that works which treated of the sciences with the utmost perspicuity1 with great precision and order1 must be understood by every body8 ,the fact is1 those who have never studied any thing will understand them better than those who have studied a great deal1 and especially than those who have written a great deal4' ,at the end of the fifth chapter1 the ,abb de ,condillac adds3 ',but1 after all1 the sciences have made progress1 because philosophers have applied themselves with more attention to observe1 and have communicated to their language that precision and accuracy which they have employed in their observations3 ,in correcting their language they reason better4' ,,contents4 ,,part ,,first4 ,of the ,formation and ,decomposition of ,ariform ,fluids1--of the ,combustion of ,simple ,bodies1 and the ,formation of ,acids1 ,page #a ,,chap4 ,i4--,of the ,combinations of ,caloric1 and the ,formation of ,elastic ,ariform ,fluids or ,gasses1 ibid4 ,,chap4 ,,ii4--,general ,views relative to the ,formation and ,composition of our ,atmosphere1 #bf ,,chap4 ,,iii4--,analysis of ,atmospheric ,air1 and its ,division into two ,elastic ,fluids2 one fit for ,respiration1 the other incapable of being respired1 #cb ,,chap4 ,,iv4--,nomenclature of the several constituent ,parts of ,atmospheric ,air1 #dh ,,chap4 ,v4--,of the ,decomposition of ,oxygen ,gas by ,sulphur1 ,phosphorus1 and ,charcoal1 and of the ,formation of ,acids in general1 #ed ,,chap4 ,,vi4--,of the ,nomenclature of ,acids in general1 and particularly of those drawn from ,nitre and ,sea ,salt1 #ff ,,chap4 ,,vii4--,of the ,decomposition of ,oxygen ,gas by means of ,metals1 and the ,formation of ,metallic ,oxyds1 #gh ,,chap4 ,,viii4--,of the ,radical ,principle of ,water1 and of its ,decomposition by ,charcoal and ,iron1 #hc ,,chap4 ,,ix4--,of the ,quantities of ,caloric disengaged from different ,species of ,combustion1 #ig ,combustion of ,phosphorus1 #ajj ,,sect4 ,i4--,combustion of ,charcoal1 #aja ,,sect4 ,,ii4--,combustion of ,hydrogen ,gas1 #ajb ,,sect4 ,,iii4--,formation of ,nitric ,acid1 #ajb ,,sect4 ,,iv4--,combustion of ,wax1 #aje ,,sect4 ,v4--,combustion of ,olive ,oil1 #ajf ,,chap4 ,x4--,of the ,combustion of ,combustible ,substances with each other1 #aji ,,chap4 ,,xi4--,observations upon ,oxyds and ,acids with several ,bases1 and upon the ,composition of ,animal and ,vegetable ,substances1 #aae ,,chap4 ,,xii4--,of the ,decomposition of ,vegetable and ,animal ,substances by the ,action of ,fire1 #abc ,,chap4 ,,xiii4--,of the ,decomposition of ,vegetable ,oxyds by the ,vinous ,fermentation1 #abi ,,chap4 ,,xiv4--,of the ,putrefactive ,fermentation1 #ada ,,chap4 ,,xv4--,of the ,acetous ,fermentation1 #adf ,,chap4 ,,xvi4--,of the ,formation of ,neutral ,salts1 and of their ,bases1 #adi ,,sect4 ,i4--,of ,potash1 #aea ,,sect4 ,,ii4--,of ,soda1 #aee ,,sect4 ,,iii4--,of ,ammoniac1 #aef ,,sect4 ,,iv4--,of ,lime1 ,magnesia1 ,barytes1 and ,argill1 #aeg ,,sect4 ,v4--,of ,metallic ,bodies1 #aei ,,chap4 ,,xvii4--,continuation of the ,observations upon ,salifiable ,bases1 and the ,formation of ,neutral ,salts1 #afa ,,part ,,ii4 ,of the ,combinations of ,acids with ,salifiable ,bases1 and of the ,formation of ,neutral ,salts1 #age ,,introduction1 ibid4 ,,table of ,simple ,substances1 #age ,,sect4 ,i4--,observations upon simple ,substances1 #agf ,,table of ,compound ,oxydable and ,acidifiable ,bases1 #agi ,,sect4 ,,ii4--,observations upon ,compound ,radicals1 #ahj ,,sect4 ,,iii4--,observations upon the ,combinations of ,light and ,caloric with different ,substances1 #ahb ,,table of the ,combinations of ,oxygen with the ,simple ,substances1 to face #ahe ,,sect4 ,,iv4--,observations upon these ,combinations1 #ahe ,,table of the ,combinations of ,oxygen with ,compound ,radicals1 #aij ,,sect4 ,v4--,observations upon these ,combinations1 #aia ,,table of the ,combinations of ,azote with the ,simple ,substances1 #aid ,,sect ,,vi4--,observations upon these ,combinations of ,azote1 #aie ,,table of the ,combinations of ,hydrogen with ,simple ,substances1 #aih ,,sect4 ,,vii4--,observations upon ,hydrogen1 and its ,combinations1 #aii ,,table of the ,binary ,combinations of ,sulphur with the ,simple ,substances1 #bjb ,,sect4 ,,viii4--,observations upon ,sulphur1 and its ,combinations1 #bjc ,,table of the ,combinations of ,phosphorus with ,simple ,substances1 #bjd ,,sect4 ,,ix4--,observations upon ,phosphorus and its ,combinations1 #bje ,,table of the ,binary ,combinations of ,charcoal1 #bjg ,,sect4 ,x4--,observations upon ,charcoal1 and its ,combinations1 #bjh ,,sect4 ,,xi4--,observations upon the ,muriatic1 ,fluoric1 and ,boracic ,radicals1 and their ,combinations1 #bji ,,sect4 ,,xii4--,observations upon the ,combinations of ,metals with each other1 #bai ,,table of the ,combinations of ,azote1 in the ,state of ,nitrous ,acid1 with the ,salifiable ,bases1 #bab ,,table of the ,combinations of ,azote1 in the ,state of ,nitric ,acid1 with the ,salifiable ,bases1 #bac ,,sect4 ,,xiii4--,observations upon ,nitrous and ,nitric ,acids1 and their ,combinations with ,salifiable ,bases1 #bad ,,table of the ,combinations of ,sulphuric ,acid with the ,salifiable ,bases1 #bah ,,sect4 ,,xiv4--,observations upon ,sulphuric ,acid1 and its ,combinations1 #bai ,,table of the ,combinations of ,sulphurous ,acid1 #bbb ,,sect4 ,,xv4--,observations upon ,sulphurous ,acid1 and its ,combinations with ,salifiable ,bases1 #bbc ,,table of the ,combinations of ,phosphorous and ,phosphoric ,acids1 #bbe ,,sect4 ,,xvi4--,observations upon ,phosphorous and ,phosphoric ,acids1 and their ,combinations with ,salifiable ,bases1 #bbf ,,table of the ,combinations of ,carbonic ,acid1 #bbh ,,sect4 ,,xvii4--,observations upon ,carbonic ,acid1 and its ,combinations with ,salifiable ,bases1 #bbi ,,table of the ,combinations of ,muriatic ,acid1 #bca ,,table of the ,combinations of ,oxygenated ,muriatic ,acid1 #bcb ,,sect4 ,,xviii4--,observations upon ,muriatic and ,oxygenated ,muriatic ,acid1 and their ,combinations with ,salifiable ,bases1 #bcc ,,table of the ,combinations of ,nitro-,muriatic ,acid1 #bcf ,,sect4 ,,xix4--,observations upon ,nitro-muriatic ,acid1 and its ,combinations with ,salifiable ,bases1 #bcg ,,table of the ,combinations of ,fluoric ,acid1 #bci ,,sect4 ,,xx4--,observations upon ,fluoric ,acid1 and its ,combinations with ,salifiable ,bases1 #bdj ,,table of the ,combinations of ,boracic ,acid1 #bdb ,,sect4 ,,xxi4--,observations upon ,boracic ,acid1 and its ,combinations with ,salifiable ,bases1 #bdc ,,table of the ,combinations of ,arseniac ,acid1 #bdf ,,sect4 ,,xxii4--,observations upon ,arseniac ,acid1 and its ,combinations with ,salifiable ,bases1 #bdg ,,sect4 ,,xxiii4--,observations upon ,molibdic ,acid1 and its ,combinations with ,salifiable ,bases1 #bdi ,,sect4 ,,xxiv4--,observations upon ,tungstic ,acid1 and its ,combinations with ,salifiable ,bases1 and a ,table of these in the order of their ,affinity1 #bea ,,table of the ,combinations of ,tartarous ,acid1 #bec ,,sect4 ,,xxv4--,observations upon ,tartarous ,acid1 and its ,combinations with ,salifiable ,bases1 #bed ,,sect4 ,,xxvi4--,observations upon ,mallic ,acid1 and its ,combinations with ,salifiable ,bases1 #bef ,,table of the ,combinations of ,citric ,acid1 #beh ,,sect4 ,,xxvii4--,observations upon ,citric ,acid1 and its ,combinations with ,salifiable ,bases1 #bei ,,table of the ,combinations of ,pyro-lignous ,acid1 #bfj ,,sect4 ,,xxviii4--,observations upon ,pyro-lignous ,acid1 and its ,combinations with ,salifiable ,bases1 #bfa ,,sect4 ,,xxix4--,observations upon ,pyro-tartarous ,acid1 and its ,combinations with ,salifiable ,bases1 ibid4 ,,table of the ,combinations of ,pyro-mucous ,acid1 #bfc ,,sect4 ,,xxx4--,observations upon ,pyro-mucous ,acid1 and its ,combinations with ,salifiable ,bases1 #bfd ,,table of the ,combinations of ,oxalic ,acid1 #bfe ,,sect4 ,,xxxi4--,observations upon ,oxalic ,acid1 and its ,combinations with ,salifiable ,bases1 #bff ,,table of the ,combinations of ,acetous ,acid1 to face #bfg ,,sect4 ,,xxxii4--,observations upon ,acetous ,acid1 and its ,combinations with the ,salifiable ,bases1 #bfg ,,table of the ,combinations of ,acetic ,acid1 #bga ,,sect4 ,,xxxiii4--,observations upon ,acetic ,acid1 and its ,combinations with ,salifiable ,bases1 #bgb ,,table of the ,combinations of ,succinic ,acid1 #bgc ,,sect4 ,,xxxiv4--,observations upon ,succinic ,acid1 and its ,combinations with ,salifiable ,bases1 #bgd ,,sect4 ,,xxxv4--,observations upon ,benzoic ,acid1 and its ,combinations with ,salifiable ,bases1 #bge ,,sect4 ,,xxxvi4--,observations upon ,camphoric ,acid1 and its ,combinations with ,salifiable ,bases1 #bgf ,,sect4 ,,xxxvii4--,observations upon ,gallic ,acid1 and its ,combinations with ,salifiable ,bases1 #bgg ,,sect4 ,,xxxviii4--,observations upon ,lactic ,acid1 and its ,combinations with ,salifiable ,bases1 #bgh ,,table of the ,combinations of ,saccholactic ,acid1 #bhj ,,sect4 ,,xxxix4--,observations upon ,saccholactic ,acid1 and its ,combination with ,salifiable ,bases1 #bha ,,table of the ,combinations of ,formic ,acid1 #bhb ,,sect4 ,,xl4--,observations upon ,formic ,acid1 and its ,combinations with the ,salifiable ,bases1 #bhc ,,sect4 ,,xli4--,observations upon the ,bombic ,acid1 and its ,combinations with the ,salifiable ,bases1 #bhd ,,table of the ,combinations of the ,sebacic ,acid1 #bhe ,,sect4 ,,xlii4--,observations upon the ,sebacic ,acid1 and its ,combinations with the ,salifiable ,bases1 #bhf ,,sect4 ,,xliii4--,observations upon the ,lithic ,acid1 and its ,combinations with the ,salifiable ,bases1 #bhg ,,table of the ,combinations of the ,prussic ,acid1 #bhh ,,sect4 ,,xliv4--,observations upon the ,prussic ,acid1 and its ,combinations with the ,salifiable ,bases1 #bhi ,,part ,,iii4 ,description of the ,instruments and ,operations of ,chemistry1 #bia ,,introduction1 #bia ,,chap4 ,i4--,of the ,instruments necessary for determining the ,absolute and ,specific ,gravities of ,solid and ,liquid ,bodies1 #bie ,,chap4 ,,ii4--,of ,gazometry1 or the ,measurement of the ,weight and ,volume of ,ariform ,substances1 #cjd ,,sect4 ,i4--,of the ,pneumato-chemical ,apparatus1 ibid4 ,,sect4 ,,ii4--,of the ,gazometer1 #cjh ,,sect4 ,,iii4--,some other methods for ,measuring the ,volume of ,gasses1 #cai ,,sect4 ,,iv4--,of the method of ,separating the different ,gasses from each other1 #cbc ,,sect4 ,v4--,of the necessary ,corrections of the ,volume of ,gasses1 according to the ,pressure of the ,atmosphere1 #cbh ,,sect4 ,,vi4--,of the ,correction relative to the ,degrees of the ,thermometer1 #cce ,,sect4 ,,vii4--,example for ,calculating the ,corrections relative to the ,variations of ,pressure and ,temperature1 #ccg ,,sect4 ,,viii4--,method of determining the ,weight of the different ,gasses1 #cdj ,,chap4 ,,iii4--,description of the ,calorimeter1 or ,apparatus for measuring ,caloric1 #cdc ,,chap4 ,,iv4--,of the ,mechanical ,operations for ,division of ,bodies1 #ceg ,,sect4 ,i4--,of ,trituration1 ,levigation1 and ,pulverization1 ibid4 ,,sect4 ,,ii4--,of ,sifting and ,washing ,powdered ,substances1 #cfa ,,sect4 ,,iii4--,of ,filtration1 #cfc ,,sect4 ,,iv4--,of ,decantation1 #cfe ,,chap4 ,v4--,of ,chemical means for ,separating the ,particles of ,bodies from each other without ,decomposition1 and for ,uniting them again1 #cfg ,,sect4 ,i4--,of the ,solution of ,salts1 #cfh ,,sect4 ,,ii4--,of ,lixiviation1 #cgc ,,sect4 ,,iii4--,of ,evaporation1 #cge ,,sect4 ,,iv4--,of ,cristallization1 #cgi ,,sect4 ,v4--,of ,simple ,distillation1 #chd ,,sect4 ,,vi4--,of ,sublimation1 #chh ,,chap4 ,,vi4--,of ,pneumato-chemical ,distillations1 ,metallic ,dissolutions1 and some other operations which require very complicated instruments1 #cij ,,sect4 ,i4--,of ,compound and ,pneumato-chemical ,distillations1 ibid4 ,,sect4 ,,ii4--,of ,metallic ,dissolutions1 #cih ,,sect4 ,,iii4--,apparatus necessary in ,experiments upon ,vinous and ,putrefactive ,fermentations1 #dja ,,sect4 ,,iv4--,apparatus for the ,decomposition of ,water1 #djd ,,chap4 ,,vii4--,of the ,composition and ,use of ,lutes1 #djg ,,chap4 ,,viii4--,of ,operations upon ,combustion and ,deflagration1 #dad ,,sect4 ,i4--,of ,combustion in general1 ibid4 ,,sect4 ,,ii4--,of the ,combustion of ,phosphorus1 #dah ,,sect4 ,,iii4--,of the ,combustion of ,charcoal1 #dbb ,,sect4 ,,iv4--,of the ,combustion of ,oils1 #dbf ,,sect4 ,v4--,of the ,combustion of ,alkohol1 #dcc ,,sect4 ,,vi4--,of the ,combustion of ,ether1 #dce ,,sect4 ,,vii4--,of the ,combustion of ,hydrogen ,gas1 and the ,formation of ,water1 #dcg ,,sect4 ,,viii4--,of the ,oxydation of ,metals1 #dda ,,chap4 ,,ix4--,of ,deflagration1 #deb ,,chap4 ,x4--,of the ,instruments necessary for ,operating upon ,bodies in very high ,temperatures1 #dfj ,,sect4 ,i4--,of ,fusion1 ibid4 ,,sect4 ,,ii4--,of ,furnaces1 #dfb ,,sect4 ,,iii4--,of increasing the ,action of ,fire1 by using ,oxygen ,gas instead of ,atmospheric ,air1 #dgd ,,appendix4 ,no4 ,i4--,,table for ,converting ,lines1 or ,twelfth ,parts of an ,inch1 and ,fractions of ,lines1 into ,decimal ,fractions of the ,inch1 #dha ,no4 ,,ii4--,,table for ,converting the ,observed ,heighth of ,water in the ,jars of the ,pneumato-,chemical ,apparatus1 expressed in ,inches and ,decimals1 into ,corresponding ,heighths of ,mercury1 #dhb ,no4 ,,iii4--,,table for ,converting the ,ounce ,measures used by ,dr ,priestley into ,french and ,english ,cubical ,inches1 #dhc ,no4 ,,iv4--,,table for ,reducing the ,degrees of ,reaumeur's ,thermometer into its corresponding ,degrees of ,fahrenheit's ,scale1 #dhd ,no4 ,v4--,,additional4--,,rules for ,converting ,french ,weights and ,measures into correspondent ,english ,denominations1 #dhe ,no4 ,,vi4--,,table of the ,weights of the different ,gasses1 at #bh ,french inches1 or #bi4hd ,english inches barometrical pressure1 and at #aj 7#ed4e7 of temperature1 expressed in ,english measure and ,english ,troy weight1 #dij ,no4 ,,vii4--,,tables of the ,specific ,gravities of different bodies1 #dia ,no4 ,,viii4--,,additional4--,,rules for ,calculating the ,absolute ,gravity in ,english ,troy ,weight of a ,cubic ,foot and ,inch1 ,english ,measure1 of any ,substance whose ,specific ,gravity is known1 #eje ,no4 ,,ix4--,,tables for ,converting ,ounces1 ,drams1 and ,grains1 ,troy1 into ,decimals of the ,troy ,pound of #ab ,ounces1 and for ,converting ,decimals of the ,pound ,troy into ,ounces1 c4 #ejh ,no4 ,x4--,,table of the ,english ,cubical ,inches and ,decimals corresponding to a determinate ,troy ,weight of ,distilled ,water at the ,temperature of #ee1 calculated from ,everard's experiment1 #eaa ,,elements ,,of ,,chemistry4 ,,part ,i4 ,of the ,formation and ,decomposition of ,ariform ,fluids--of the ,combustion of ,simple ,bodies--and the ,formation of ,acids4 ,,chap4 ,i4 ,of the ,combinations of ,caloric1 and the ,formation of ,elastic ,ariform ,fluids4 ,that every body1 whether solid or fluid1 is augmented in all its dimensions by any increase of its sensible heat1 was long ago fully established as a physical axiom1 or universal proposition1 by the celebrated ,boerhaave4 ,such facts as have been adduced for controverting the generality of this principle offer only fallacious results1 or1 at least1 such as are so complicated with foreign circumstances as to mislead the judgment3 ,but1 when we separately consider the effects1 so as to deduce each from the cause to which they separately belong1 it is easy to perceive that the separation of particles by heat is a constant and general law of nature4 ,when we have heated a solid body to a certain degree1 and have thereby caused its particles to separate from each other1 if we allow the body to cool1 its particles again approach each other in the same proportion in which they were separated by the increased temperature2 the body returns through the same degrees of expansion which it before extended through2 and1 if it be brought back to the same temperature from which we set out at the commencement of the experiment1 it recovers exactly the same dimensions which it formerly occupied4 ,but1 as we are still very far from being able to arrive at the degree of absolute cold1 or deprivation of all heat1 being unacquainted with any degree of coldness which we cannot suppose capable of still farther augmentation1 it follows1 that we are still incapable of causing the ultimate particles of bodies to approach each other as near as is possible2 and1 consequently1 that the particles of all bodies do not touch each other in any state hitherto known1 which1 tho' a very singular conclusion1 is yet impossible to be denied4 ,it is supposed1 that1 since the particles of bodies are thus continually impelled by heat to separate from each other1 they would have no connection between themselves2 and1 of consequence1 that there could be no solidity in nature1 unless they were held together by some other power which tends to unite them1 and1 so to speak1 to chain them together2 which power1 whatever be its cause1 or manner of operation1 we name ,attraction4 ,thus the particles of all bodies may be considered as subjected to the action of two opposite powers1 the one repulsive1 the other attractive1 between which they remain in equilibrio4 ,so long as the attractive force remains stronger1 the body must continue in a state of solidity2 but if1 on the contrary1 heat has so far removed these particles from each other1 as to place them beyond the sphere of attraction1 they lose the adhesion they before had with each other1 and the body ceases to be solid4 ,water gives us a regular and constant example of these facts2 whilst below ,zero#b of the ,french thermometer1 or #cb of ,fahrenheit1 it remains solid1 and is called ice4 ,above that degree of temperature1 its particles being no longer held together by reciprocal attraction1 it becomes liquid2 and1 when we raise its temperature above #hj1 7#bab7 its particles1 giving way to the repulsion caused by the heat1 assume the state of vapour or gas1 and the water is changed into an ariform fluid4 ,the same may be affirmed of all bodies in nature3 ,they are either solid or liquid1 or in the state of elastic ariform vapour1 according to the proportion which takes place between the attractive force inherent in their particles1 and the repulsive power of the heat acting upon these2 or1 what amounts to the same thing1 in proportion to the degree of heat to which they are exposed4 ,it is difficult to comprehend these phenomena1 without admitting them as the effects of a real and material substance1 or very subtile fluid1 which1 insinuating itself between the particles of bodies1 separates them from each other2 and1 even allowing the existence of this fluid to be hypothetical1 we shall see in the sequel1 that it explains the phenomena of nature in a very satisfactory manner4 ,this substance1 whatever it is1 being the cause of heat1 or1 in other words1 the sensation which we call warmth being caused by the accumulation of this substance1 we cannot1 in strict language1 distinguish it by the term heat2 because the same name would then very improperly express both cause and effect4 ,for this reason1 in the memoir which ,i published in #agggc1 ,i gave it the names of igneous fluid and matter of heat4 ,and1 since that time1 in the work#d published by ,mr de ,morveau1 ,mr ,berthollet1 ,mr de ,fourcroy1 and myself1 upon the reformation of chemical nomenclature1 we thought it necessary to banish all periphrastic expressions1 which both lengthen physical language1 and render it more tedious and less distinct1 and which even frequently does not convey sufficiently just ideas of the subject intended4 ,wherefore1 we have distinguished the cause of heat1 or that exquisitely elastic fluid which produces it1 by the term of caloric4 ,besides1 that this expression fulfils our object in the system which we have adopted1 it possesses this farther advantage1 that it accords with every species of opinion1 since1 strictly speaking1 we are not obliged to suppose this to be a real substance2 it being sufficient1 as will more clearly appear in the sequel of this work1 that it be considered as the repulsive cause1 whatever that may be1 which separates the particles of matter from each other2 so that we are still at liberty to investigate its effects in an abstract and mathematical manner4 ,in the present state of our knowledge1 we are unable to determine whether light be a modification of caloric1 or if caloric be1 on the contrary1 a modification of light4 ,this1 however1 is indisputable1 that1 in a system where only decided facts are admissible1 and where we avoid1 as far as possible1 to suppose any thing to be that is not really known to exist1 we ought provisionally to distinguish1 by distinct terms1 such things as are known to produce different effects4 ,we therefore distinguish light from caloric2 though we do not therefore deny that these have certain qualities in common1 and that1 in certain circumstances1 they combine with other bodies almost in the same manner1 and produce1 in part1 the same effects4 ,what ,i have already said may suffice to determine the idea affixed to the word caloric2 but there remains a more difficult attempt1 which is1 to give a just conception of the manner in which caloric acts upon other bodies4 ,since this subtile matter penetrates through the pores of all known substances2 since there are no vessels through which it cannot escape1 and1 consequently1 as there are none which are capable of retaining it1 we can only come at the knowledge of its properties by effects which are fleeting1 and difficultly ascertainable4 ,it is in these things which we neither see nor feel1 that it is especially necessary to guard against the extravagancy of our imagination1 which forever inclines to step beyond the bounds of truth1 and is very difficultly restrained within the narrow line of facts4 ,we have already seen1 that the same body becomes solid1 or fluid1 or ariform1 according to the quantity of caloric by which it is penetrated2 or1 to speak more strictly1 according as the repulsive force exerted by the caloric is equal to1 stronger1 or weaker1 than the attraction of the particles of the body it acts upon4 ,but1 if these two powers only existed1 bodies would become liquid at an indivisible degree of the thermometer1 and would almost instantaneously pass from the solid state of aggregation to that of ariform elasticity4 ,thus water1 for instance1 at the very moment when it ceases to be ice1 would begin to boil1 and would be transformed into an ariform fluid1 having its particles scattered indefinitely through the surrounding space4 ,that this does not happen1 must depend upon the action of some third power4 ,the pressure of the atmosphere prevents this separation1 and causes the water to remain in the liquid state till it be raised to #hj of temperature 7#bab7 above zero of the ,french thermometer1 the quantity of caloric which it receives in the lowest temperature being insufficient to overcome the pressure of the atmosphere4 ,whence it appears that1 without this atmospheric pressure1 we should not have any permanent liquid1 and should only be able to see bodies in that state of existence in the very instant of melting1 as the smallest additional caloric would instantly separate their particles1 and dissipate them through the surrounding medium4 ,besides1 without this atmospheric pressure1 we should not even have any ariform fluids1 strictly speaking1 because the moment the force of attraction is overcome by the repulsive power of the caloric1 the particles would separate themselves indefinitely1 having nothing to give limits to their expansion1 unless their own gravity might collect them together1 so as to form an atmosphere4 ,simple reflection upon the most common experiments is sufficient to evince the truth of these positions4 ,they are more particularly proved by the following experiment1 which ,i published in the ,memoirs of the ,french ,academy for #aggg1 p4 #dbf4 ,having filled with sulphuric ether#e a small narrow glass vessel1 ,a1 7,plate ,,vii4 ,fig4 #ag471 standing upon its stalk ,p1 the vessel1 which is from twelve to fifteen lines diameter1 is to be covered by a wet bladder1 tied round its neck with several turns of strong thread2 for greater security1 fix a second bladder over the first4 ,the vessel should be filled in such a manner with the ether1 as not to leave the smallest portion of air between the liquor and the bladder4 ,it is now to be placed under the recipient ,,bcd of an air-pump1 of which the upper part ,b ought to be fitted with a leathern lid1 through which passes a wire ,,ef1 having its point ,f very sharp2 and in the same receiver there ought to be placed the barometer ,,gh4 ,the whole being thus disposed1 let the recipient be exhausted1 and then1 by pushing down the wire ,,ef1 we make a hole in the bladder4 ,immediately the ether begins to boil with great violence1 and is changed into an elastic ariform fluid1 which fills the receiver4 ,if the quantity of ether be sufficient to leave a few drops in the phial after the evaporation is finished1 the elastic fluid produced will sustain the mercury in the barometer attached to the air-pump1 at eight or ten inches in winter1 and from twenty to twenty-five in summer#f4 ,to render this experiment more complete1 we may introduce a small thermometer into the phial ,a1 containing the ether1 which will descend considerably during the evaporation4 ,the only effect produced in this experiment is1 the taking away the weight of the atmosphere1 which1 in its ordinary state1 presses on the surface of the ether2 and the effects resulting from this removal evidently prove1 that1 in the ordinary temperature of the earth1 ether would always exist in an ariform state1 but for the pressure of the atmosphere1 and that the passing of the ether from the liquid to the ariform state is accompanied by a considerable lessening of heat2 because1 during the evaporation1 a part of the caloric1 which was before in a free state1 or at least in equilibrio in the surrounding bodies1 combines with the ether1 and causes it to assume the ariform state4 ,the same experiment succeeds with all evaporable fluids1 such as alkohol1 water1 and even mercury2 with this difference1 that the atmosphere formed in the receiver by alkohol only supports the attached barometer about one inch in winter1 and about four or five inches in summer2 that formed by water1 in the same situation1 raises the mercury only a few lines1 and that by quicksilver but a few fractions of a line4 ,there is therefore less fluid evaporated from alkohol than from ether1 less from water than from alkohol1 and still less from mercury than from either2 consequently there is less caloric employed1 and less cold produced1 which quadrates exactly with the results of these experiments4 ,another species of experiment proves very evidently that the ariform state is a modification of bodies dependent on the degree of temperature1 and on the pressure which these bodies undergo4 ,in a ,memoir read by ,mr de la ,place and me to the ,academy in #aggg1 which has not been printed1 we have shown1 that1 when ether is subjected to a pressure equal to twenty-eight inches of the barometer1 or about the medium pressure of the atmosphere1 it boils at the temperature of about #cb 7#ajd71 or #cc 7#ajf4be71 of the thermometer4 ,mr de ,luc1 who has made similar experiments with spirit of wine1 finds it boils at #fg 7#ahb4ge74 ,and all the world knows that water boils at #hj 7#bab74 ,now1 boiling being only the evaporation of a liquid1 or the moment of its passing from the fluid to the ariform state1 it is evident that1 if we keep ether continually at the temperature of #cc 7#ajf4be71 and under the common pressure of the atmosphere1 we shall have it always in an elastic ariform state2 and that the same thing will happen with alkohol when above #fg 7#ahb4ge71 and with water when above #hj 7#bab72 all which are perfectly conformable to the following experiment#g4 ,i filled a large vessel ,,abcd 7,plate ,,vii4 ,fig4 #af47 with water1 at #ce 7#aaj4ge71 or #cf 7#aac72 ,i suppose the vessel transparent1 that we may see what takes place in the experiment2 and we can easily hold the hands in water at that temperature without inconvenience4 ,into it ,i plunged some narrow necked bottles ,f1 ,g1 which were filled with the water1 after which they were turned up1 so as to rest on their mouths on the bottom of the vessel4 ,having next put some ether into a very small matrass1 with its neck a b c1 twice bent as in the ,plate1 ,i plunged this matrass into the water1 so as to have its neck inserted into the mouth of one of the bottles ,f4 ,immediately upon feeling the effects of the heat communicated to it by the water in the vessel ,,abcd it began to boil2 and the caloric entering into combination with it1 changed it into elastic ariform fluid1 with which ,i filled several bottles successively1 ,f1 ,g1 c4 ,this is not the place to enter upon the examination of the nature and properties of this ariform fluid1 which is extremely inflammable2 but1 confining myself to the object at present in view1 without anticipating circumstances1 which ,i am not to suppose the reader to know1 ,i shall only observe1 that the ether1 from this experiment1 is almost only capable of existing in the ariform state in our world2 for1 if the weight of our atmosphere was only equal to between #bj and #bd inches of the barometer1 instead of #bh inches1 we should never be able to obtain ether in the liquid state1 at least in summer2 and the formation of ether would consequently be impossible upon mountains of a moderate degree of elevation1 as it would be converted into gas immediately upon being produced1 unless we employed recipients of extraordinary strength1 together with refrigeration and compression4 ,and1 lastly1 the temperature of the blood being nearly that at which ether passes from the liquid to the ariform state1 it must evaporate in the primae viae1 and consequently it is very probable the medical properties of this fluid depend chiefly upon its mechanical effect4 ,these experiments succeed better with nitrous ether1 because it evaporates in a lower temperature than sulphuric ether4 ,it is more difficult to obtain alkohol in the ariform state2 because1 as it requires #fg 7#ahb4ge7 to reduce it to vapour1 the water of the bath must be almost boiling1 and consequently it is impossible to plunge the hands into it at that temperature4 ,it is evident that1 if water were used in the foregoing experiment1 it would be changed into gas1 when exposed to a temperature superior to that at which it boils4 ,although thoroughly convinced of this1 ,mr de la ,place and myself judged it necessary to confirm it by the following direct experiment4 ,we filled a glass jar ,a1 7,plate ,,vii4 ,fig4 #e47 with mercury1 and placed it with its mouth downwards in a dish ,b1 likewise filled with mercury1 and having introduced about two gross of water into the jar1 which rose to the top of the mercury at ,,cd2 we then plunged the whole apparatus into an iron boiler ,,efgh1 full of boiling sea-water of the temperature of #he 7#abc4be71 placed upon the furnace ,,ghik4 ,immediately upon the water over the mercury attaining the temperature of #hj 7#bab71 it began to boil2 and1 instead of only filling the small space ,,acd1 it was converted into an ariform fluid1 which filled the whole jar2 the mercury even descended below the surface of that in the dish ,b2 and the jar must have been overturned1 if it had not been very thick and heavy1 and fixed to the dish by means of iron-wire4 ,immediately after withdrawing the apparatus from the boiler1 the vapour in the jar began to condense1 and the mercury rose to its former station2 but it returned again to the ariform state a few seconds after replacing the apparatus in the boiler4 ,we have thus a certain number of substances1 which are convertible into elastic ariform fluids by degrees of temperature1 not much superior to that of our atmosphere4 ,we shall afterwards find that there are several others which undergo the same change in similar circumstances1 such as muriatic or marine acid1 ammoniac or volatile alkali1 the carbonic acid or fixed air1 the sulphurous acid1 c4 ,all of these are permanently elastic in or about the mean temperature of the atmosphere1 and under its common pressure4 ,all these facts1 which could be easily multiplied if necessary1 give me full right to assume1 as a general principle1 that almost every body in nature is susceptible of three several states of existence1 solid1 liquid1 and ariform1 and that these three states of existence depend upon the quantity of caloric combined with the body4 ,henceforwards ,i shall express these elastic ariform fluids by the generic term gas2 and in each species of gas ,i shall distinguish between the caloric1 which in some measure serves the purpose of a solvent1 and the substance1 which in combination with the caloric1 forms the base of the gas4 ,to these bases of the different gases1 which are hitherto but little known1 we have been obliged to assign names2 these ,i shall point out in ,chap4 ,,iv4 of this work1 when ,i have previously given an account of the phenomena attendant upon the heating and cooling of bodies1 and when ,i have established precise ideas concerning the composition of our atmosphere4 ,we have already shown1 that the particles of every substance in nature exist in a certain state of equilibrium1 between that attraction which tends to unite and keep the particles together1 and the effects of the caloric which tends to separate them4 ,hence the caloric not only surrounds the particles of all bodies on every side1 but fills up every interval which the particles of bodies leave between each other4 ,we may form an idea of this1 by supposing a vessel filled with small spherical leaden bullets1 into which a quantity of fine sand is poured1 which1 insinuating into the intervals between the bullets1 will fill up every void4 ,the balls1 in this comparison1 are to the sand which surrounds them exactly in the same situation as the particles of bodies are with respect to the caloric2 with this difference only1 that the balls are supposed to touch each other1 whereas the particles of bodies are not in contact1 being retained at a small distance from each other1 by the caloric4 ,if1 instead of spherical balls1 we substitute solid bodies of a hexahedral1 octohedral1 or any other regular figure1 the capacity of the intervals between them will be lessened1 and consequently will no longer contain the same quantity of sand4 ,the same thing takes place1 with respect to natural bodies2 the intervals left between their particles are not of equal capacity1 but vary in consequence of the different figures and magnitude of their particles1 and of the distance at which these particles are maintained1 according to the existing proportion between their inherent attraction1 and the repulsive force exerted upon them by the caloric4 ,in this manner we must understand the following expression1 introduced by the ,english philosophers1 who have given us the first precise ideas upon this subject2 the capacity of bodies for containing the matter of heat4 ,as comparisons with sensible objects are of great use in assisting us to form distinct notions of abstract ideas1 we shall endeavour to illustrate this1 by instancing the phenomena which take place between water and bodies which are wetted and penetrated by it1 with a few reflections4 ,if we immerge equal pieces of different kinds of wood1 suppose cubes of one foot each1 into water1 the fluid gradually insinuates itself into their pores1 and the pieces of wood are augmented both in weight and magnitude3 ,but each species of wood will imbibe a different quantity of water2 the lighter and more porous woods will admit a larger1 the compact and closer grained will admit of a lesser quantity2 for the proportional quantities of water imbibed by the pieces will depend upon the nature of the constituent particles of the wood1 and upon the greater or lesser affinity subsisting between them and water4 ,very resinous wood1 for instance1 though it may be at the same time very porous1 will admit but little water4 ,we may therefore say1 that the different kinds of wood possess different capacities for receiving water2 we may even determine1 by means of the augmentation of their weights1 what quantity of water they have actually absorbed2 but1 as we are ignorant how much water they contained1 previous to immersion1 we cannot determine the absolute quantity they contain1 after being taken out of the water4 ,the same circumstances undoubtedly take place1 with bodies that are immersed in caloric2 taking into consideration1 however1 that water is an incompressible fluid1 whereas caloric is1 on the contrary1 endowed with very great elasticity2 or1 in other words1 the particles of caloric have a great tendency to separate from each other1 when forced by any other power to approach2 this difference must of necessity occasion very considerable diversities in the results of experiments made upon these two substances4 ,having established these clear and simple propositions1 it will be very easy to explain the ideas which ought to be affixed to the following expressions1 which are by no means synonimous1 but possess each a strict and determinate meaning1 as in the following definitions3 ,free caloric1 is that which is not combined in any manner with any other body4 ,but1 as we live in a system to which caloric has a very strong adhesion1 it follows that we are never able to obtain it in the state of absolute freedom4 ,combined caloric1 is that which is fixed in bodies by affinity or elective attraction1 so as to form part of the substance of the body1 even part of its solidity4 ,by the expression specific caloric of bodies1 we understand the respective quantities of caloric requisite for raising a number of bodies of the same weight to an equal degree of temperature4 ,this proportional quantity of caloric depends upon the distance between the constituent particles of bodies1 and their greater or lesser degrees of cohesion2 and this distance1 or rather the space or void resulting from it1 is1 as ,i have already observed1 called the capacity of bodies for containing caloric4 ,heat1 considered as a sensation1 or1 in other words1 sensible heat1 is only the effect produced upon our sentient organs1 by the motion or passage of caloric1 disengaged from the surrounding bodies4 ,in general1 we receive impressions only in consequence of motion1 and we might establish it as an axiom1 ,that1 ,,without ,,motion1 ,,there ,,is ,,no ,,sensation4 ,this general principle applies very accurately to the sensations of heat and cold3 ,when we touch a cold body1 the caloric which always tends to become in equilibrio in all bodies1 passes from our hand into the body we touch1 which gives us the feeling or sensation of cold4 ,the direct contrary happens1 when we touch a warm body1 the caloric then passing from the body into our hand1 produces the sensation of heat4 ,if the hand and the body touched be of the same temperature1 or very nearly so1 we receive no impression1 either of heat or cold1 because there is no motion or passage of caloric2 and thus no sensation can take place1 without some correspondent motion to occasion it4 ,when the thermometer rises1 it shows1 that free caloric is entering into the surrounding bodies3 ,the thermometer1 which is one of these1 receives its share in proportion to its mass1 and to the capacity which it possesses for containing caloric4 ,the change therefore which takes place upon the thermometer1 only announces a change of place of the caloric in those bodies1 of which the thermometer forms one part2 it only indicates the portion of caloric received1 without being a measure of the whole quantity disengaged1 displaced1 or absorbed4 ,the most simple and most exact method for determining this latter point1 is that described by ,mr de la ,place1 in the ,memoirs of the ,academy1 ,no4 #aghj1 p4 #cfd2 a summary explanation of which will be found towards the conclusion of this work4 ,this method consists in placing a body1 or a combination of bodies1 from which caloric is disengaging1 in the midst of a hollow sphere of ice2 and the quantity of ice melted becomes an exact measure of the quantity of caloric disengaged4 ,it is possible1 by means of the apparatus which we have caused to be constructed upon this plan1 to determine1 not as has been pretended1 the capacity of bodies for containing heat1 but the ratio of the increase or diminution of capacity produced by determinate degrees of temperature4 ,it is easy with the same apparatus1 by means of divers combinations of experiments1 to determine the quantity of caloric requisite for converting solid substances into liquids1 and liquids into elastic ariform fluids2 and1 vice versa1 what quantity of caloric escapes from elastic vapours in changing to liquids1 and what quantity escapes from liquids during their conversion into solids4 ,perhaps1 when experiments have been made with sufficient accuracy1 we may one day be able to determine the proportional quantity of caloric1 necessary for producing the several species of gasses4 ,i shall hereafter1 in a separate chapter1 give an account of the principal results of such experiments as have been made upon this head4 ,it remains1 before finishing this article1 to say a few words relative to the cause of the elasticity of gasses1 and of fluids in the state of vapour4 ,it is by no means difficult to perceive that this elasticity depends upon that of caloric1 which seems to be the most eminently elastic body in nature4 ,nothing is more readily conceived1 than that one body should become elastic by entering into combination with another body possessed of that quality4 ,we must allow that this is only an explanation of elasticity1 by an assumption of elasticity1 and that we thus only remove the difficulty one step farther1 and that the nature of elasticity1 and the reason for caloric being elastic1 remains still unexplained4 ,elasticity in the abstract is nothing more than that quality of the particles of bodies by which they recede from each other when forced together4 ,this tendency in the particles of caloric to separate1 takes place even at considerable distances4 ,we shall be satisfied of this1 when we consider that air is susceptible of undergoing great compression1 which supposes that its particles were previously very distant from each other2 for the power of approaching together certainly supposes a previous distance1 at least equal to the degree of approach4 ,consequently1 those particles of the air1 which are already considerably distant from each other1 tend to separate still farther4 ,in fact1 if we produce ,boyle's vacuum in a large receiver1 the very last portion of air which remains spreads itself uniformly through the whole capacity of the vessel1 however large1 fills it completely throughout1 and presses every where against its sides3 ,we cannot1 however1 explain this effect1 without supposing that the particles make an effort to separate themselves on every side1 and we are quite ignorant at what distance1 or what degree of rarefaction1 this effort ceases to act4 ,here1 therefore1 exists a true repulsion between the particles of elastic fluids2 at least1 circumstances take place exactly as if such a repulsion actually existed2 and we have very good right to conclude1 that the particles of caloric mutually repel each other4 ,when we are once permitted to suppose this repelling force1 the rationale of the formation of gasses1 or ariform fluids1 becomes perfectly simple2 tho' we must1 at the same time1 allow1 that it is extremely difficult to form an accurate conception of this repulsive force acting upon very minute particles placed at great distances from each other4 ,it is1 perhaps1 more natural to suppose1 that the particles of caloric have a stronger mutual attraction than those of any other substance1 and that these latter particles are forced asunder in consequence of this superior attraction between the particles of the caloric1 which forces them between the particles of other bodies1 that they may be able to reunite with each other4 ,we have somewhat analogous to this idea in the phenomena which occur when a dry sponge is dipt into water3 ,the sponge swells2 its particles separate from each other2 and all its intervals are filled up by the water4 ,it is evident1 that the sponge1 in the act of swelling1 has acquired a greater capacity for containing water than it had when dry4 ,but we cannot certainly maintain1 that the introduction of water between the particles of the sponge has endowed them with a repulsive power1 which tends to separate them from each other2 on the contrary1 the whole phenomena are produced by means of attractive powers2 and these are1 first1 ,the gravity of the water1 and the power which it exerts on every side1 in common with all other fluids2 #b;dly1 ,the force of attraction which takes place between the particles of the water1 causing them to unite together2 #c;dly1 ,the mutual attraction of the particles of the sponge with each other2 and1 lastly1 ,the reciprocal attraction which exists between the particles of the sponge and those of the water4 ,it is easy to understand1 that the explanation of this fact depends upon properly appreciating the intensity of1 and connection between1 these several powers4 ,it is probable1 that the separation of the particles of bodies1 occasioned by caloric1 depends in a similar manner upon a certain combination of different attractive powers1 which1 in conformity with the imperfection of our knowledge1 we endeavour to express by saying1 that caloric communicates a power of repulsion to the particles of bodies4 ,,footnotes3 #b ,whenever the degree of heat occurs in this work1 it is stated by the author according to ,reaumur's scale4 ,the degrees within brackets are the correspondent degrees of ,fahrenheit's scale1 added by the translator4 ,e4 #c ,collections of the ,french ,academy of ,sciences for that year1 p4 #dbj4 #d ,chemical ,nomenclature4 #e ,as ,i shall afterwards give a definition1 and explain the properties of the liquor called ether1 ,i shall only premise here1 that it is a very volatile inflammable liquor1 having a considerably smaller specific gravity than water1 or even spirit of wine4--,a4 #f ,it would have been more satisfactory if the ,author had specified the degrees of the thermometer at which these heights of the mercury in the barometer are produced4 #g ,vide ,memoirs of the ,french ,academy1 anno #aghj1 p4 #cce4--;,a4 ,,chap4 ,,ii4 ,general ,views relative to the ,formation and ,composition of our ,atmosphere4 ,these views which ,i have taken of the formation of elastic ariform fluids or gasses1 throw great light upon the original formation of the atmospheres of the planets1 and particularly that of our earth4 ,we readily conceive1 that it must necessarily consist of a mixture of the following substances3 ,first1 ,of all bodies that are susceptible of evaporation1 or1 more strictly speaking1 which are capable of retaining the state of ariform elasticity in the temperature of our atmosphere1 and under a pressure equal to that of a column of twenty-eight inches of quicksilver in the barometer2 and1 secondly1 ,of all substances1 whether liquid or solid1 which are capable of being dissolved by this mixture of different gasses4 ,the better to determine our ideas relating to this subject1 which has not hitherto been sufficiently considered1 let us1 for a moment1 conceive what change would take place in the various substances which compose our earth1 if its temperature were suddenly altered4 ,if1 for instance1 we were suddenly transported into the region of the planet ,mercury1 where probably the common temperature is much superior to that of boiling water1 the water of the earth1 and all the other fluids which are susceptible of the gasseous state1 at a temperature near to that of boiling water1 even quicksilver itself1 would become rarified2 and all these substances would be changed into permanent ariform fluids or gasses1 which would become part of the new atmosphere4 ,these new species of airs or gasses would mix with those already existing1 and certain reciprocal decompositions and new combinations would take place1 until such time as all the elective attractions or affinities subsisting amongst all these new and old gasseous substances had operated fully2 after which1 the elementary principles composing these gasses1 being saturated1 would remain at rest4 ,we must attend to this1 however1 that1 even in the above hypothetical situation1 certain bounds would occur to the evaporation of these substances1 produced by that very evaporation itself2 for as1 in proportion to the increase of elastic fluids1 the pressure of the atmosphere would be augmented1 as every degree of pressure tends1 in some measure1 to prevent evaporation1 and as even the most evaporable fluids can resist the operation of a very high temperature without evaporating1 if prevented by a proportionally stronger compression1 water and all other liquids being able to sustain a red heat in ,papin's digester2 we must admit1 that the new atmosphere would at last arrive at such a degree of weight1 that the water which had not hitherto evaporated would cease to boil1 and1 of consequence1 would remain liquid2 so that1 even upon this supposition1 as in all others of the same nature1 the increasing gravity of the atmosphere would find certain limits which it could not exceed4 ,we might even extend these reflections greatly farther1 and examine what change might be produced in such situations upon stones1 salts1 and the greater part of the fusible substances which compose the mass of our earth4 ,these would be softened1 fused1 and changed into fluids1 c43 ,but these speculations carry me from my object1 to which ,i hasten to return4 ,by a contrary supposition to the one we have been forming1 if the earth were suddenly transported into a very cold region1 the water which at present composes our seas1 rivers1 and springs1 and probably the greater number of the fluids we are acquainted with1 would be converted into solid mountains and hard rocks1 at first diaphanous and homogeneous1 like rock crystal1 but which1 in time1 becoming mixed with foreign and heterogeneous substances1 would become opake stones of various colours4 ,in this case1 the air1 or at least some part of the ariform fluids which now compose the mass of our atmosphere1 would doubtless lose its elasticity for want of a sufficient temperature to retain them in that state3 ,they would return to the liquid state of existence1 and new liquids would be formed1 of whose properties we cannot1 at present1 form the most distant idea4 ,these two opposite suppositions give a distinct proof of the following corollaries3 ,first1 ,that solidity1 liquidity1 and ariform elasticity1 are only three different states of existence of the same matter1 or three particular modifications which almost all substances are susceptible of assuming successively1 and which solely depend upon the degree of temperature to which they are exposed2 or1 in other words1 upon the quantity of caloric with which they are penetrated#h4 #b;dly1 ,that it is extremely probable that air is a fluid naturally existing in a state of vapour2 or1 as we may better express it1 that our atmosphere is a compound of all the fluids which are susceptible of the vaporous or permanently elastic state1 in the usual temperature1 and under the common pressure4 #c;dly1 ,that it is not impossible we may discover1 in our atmosphere1 certain substances naturally very compact1 even metals themselves2 as a metallic substance1 for instance1 only a little more volatile than mercury1 might exist in that situation4 ,amongst the fluids with which we are acquainted1 some1 as water and alkohol1 are susceptible of mixing with each other in all proportions2 whereas others1 on the contrary1 as quicksilver1 water1 and oil1 can only form a momentary union2 and1 after being mixed together1 separate and arrange themselves according to their specific gravities4 ,the same thing ought to1 or at least may1 take place in the atmosphere4 ,it is possible1 and even extremely probable1 that1 both at the first creation1 and every day1 gasses are formed1 which are difficultly miscible with atmospheric air1 and are continually separating from it4 ,if these gasses be specifically lighter than the general atmospheric mass1 they must1 of course1 gather in the higher regions1 and form strata that float upon the common air4 ,the phenomena which accompany igneous meteors induce me to believe1 that there exists in the upper parts of our atmosphere a stratum of inflammable fluid in contact with those strata of air which produce the phenomena of the aurora borealis and other fiery meteors4--,i mean hereafter to pursue this subject in a separate treatise4 ,,footnotes3 #h ,the degree of pressure which they undergo must be taken into account4 ,e4 ,,chap4 ,,iii4 ,analysis of ,atmospheric ,air1 and its ,division into two ,elastic ,fluids2 the one fit for ,respiration1 the other incapable of being respired4 ,from what has been premised1 it follows1 that our atmosphere is composed of a mixture of every substance capable of retaining the gasseous or ariform state in the common temperature1 and under the usual pressure which it experiences4 ,these fluids constitute a mass1 in some measure homogeneous1 extending from the surface of the earth to the greatest height hitherto attained1 of which the density continually decreases in the inverse ratio of the superincumbent weight4 ,but1 as ,i have before observed1 it is possible that this first stratum is surmounted by several others consisting of very different fluids4 ,our business1 in this place1 is to endeavour to determine1 by experiments1 the nature of the elastic fluids which compose the inferior stratum of air which we inhabit4 ,modern chemistry has made great advances in this research2 and it will appear by the following details that the analysis of atmospherical air has been more rigorously determined than that of any other substance of the class4 ,chemistry affords two general methods of determining the constituent principles of bodies1 the method of analysis1 and that of synthesis4 ,when1 for instance1 by combining water with alkohol1 we form the species of liquor called1 in commercial language1 brandy or spirit of wine1 we certainly have a right to conclude1 that brandy1 or spirit of wine1 is composed of alkohol combined with water4 ,we can produce the same result by the analytical method2 and in general it ought to be considered as a principle in chemical science1 never to rest satisfied without both these species of proofs4 ,we have this advantage in the analysis of atmospherical air1 being able both to decompound it1 and to form it a new in the most satisfactory manner4 ,i shall1 however1 at present confine myself to recount such experiments as are most conclusive upon this head2 and ,i may consider most of these as my own1 having either first invented them1 or having repeated those of others1 with the intention of analysing atmospherical air1 in perfectly new points of view4 ,i took a matrass 7,a1 fig4 #ad4 plate ,,ii47 of about #cf cubical inches capacity1 having a long neck ,b ,c ,d ,e1 of six or seven lines internal diameter1 and having bent the neck as in ,plate ,,iv4 ,fig4 #b4 so as to allow of its being placed in the furnace ,m ,m ,n ,n1 in such a manner that the extremity of its neck ,e might be inserted under a bell-glass ,f ,g1 placed in a trough of quicksilver ,r ,r ,s ,s2 ,i introduced four ounces of pure mercury into the matrass1 and1 by means of a syphon1 exhausted the air in the receiver ,f ,g1 so as to raise the quicksilver to ,l ,l1 and ,i carefully marked the height at which it stood by pasting on a slip of paper4 ,having accurately noted the height of the thermometer and barometer1 ,i lighted a fire in the furnace ,m ,m ,n ,n1 which ,i kept up almost continually during twelve days1 so as to keep the quicksilver always almost at its boiling point4 ,nothing remarkable took place during the first day3 ,the ,mercury1 though not boiling1 was continually evaporating1 and covered the interior surface of the vessels with small drops1 at first very minute1 which gradually augmenting to a sufficient size1 fell back into the mass at the bottom of the vessel4 ,on the second day1 small red particles began to appear on the surface of the mercury1 which1 during the four or five following days1 gradually increased in size and number2 after which they ceased to increase in either respect4 ,at the end of twelve days1 seeing that the calcination of the mercury did not at all increase1 ,i extinguished the fire1 and allowed the vessels to cool4 ,the bulk of air in the body and neck of the matrass1 and in the bell-glass1 reduced to a medium of #bh inches of the barometer and #aj 7#ed4e7 of the thermometer1 at the commencement of the experiment was about #ej cubical inches4 ,at the end of the experiment the remaining air1 reduced to the same medium pressure and temperature1 was only between #db and #dc cubical inches2 consequently it had lost about #a_/f of its bulk4 ,afterwards1 having collected all the red particles1 formed during the experiment1 from the running mercury in which they floated1 ,i found these to amount to #de grains4 ,i was obliged to repeat this experiment several times1 as it is difficult in one experiment both to preserve the whole air upon which we operate1 and to collect the whole of the red particles1 or calx of mercury1 which is formed during the calcination4 ,it will often happen in the sequel1 that ,i shall1 in this manner1 give in one detail the results of two or three experiments of the same nature4 ,the air which remained after the calcination of the mercury in this experiment1 and which was reduced to #e_/f of its former bulk1 was no longer fit either for respiration or for combustion2 animals being introduced into it were suffocated in a few seconds1 and when a taper was plunged into it1 it was extinguished as if it had been immersed into water4 ,in the next place1 ,i took the #de grains of red matter formed during this experiment1 which ,i put into a small glass retort1 having a proper apparatus for receiving such liquid1 or gasseous product1 as might be extracted3 ,having applied a fire to the retort in a furnace1 ,i observed that1 in proportion as the red matter became heated1 the intensity of its colour augmented4 ,when the retort was almost red hot1 the red matter began gradually to decrease in bulk1 and in a few minutes after it disappeared altogether2 at the same time #da-a_/b grains of running mercury were collected in the recipient1 and #g or #h cubical inches of elastic fluid1 greatly more capable of supporting both respiration and combustion than atmospherical air1 were collected in the bell-glass4 ,a part of this air being put into a glass tube of about an inch diameter1 showed the following properties3 ,a taper burned in it with a dazzling splendour1 and charcoal1 instead of consuming quietly as it does in common air1 burnt with a flame1 attended with a decrepitating noise1 like phosphorus1 and threw out such a brilliant light that the eyes could hardly endure it4 ,this species of air was discovered almost at the same time by ,mr ,priestley1 ,mr ,scheele1 and myself4 ,mr ,priestley gave it the name of dephlogisticated air1 ,mr ,scheele called it empyreal air4 ,at first ,i named it highly respirable air1 to which has since been substituted the term of vital air4 ,we shall presently see what we ought to think of these denominations4 ,in reflecting upon the circumstances of this experiment1 we readily perceive1 that the mercury1 during its calcination1 absorbs the salubrious and respirable part of the air1 or1 to speak more strictly1 the base of this respirable part2 that the remaining air is a species of mephitis1 incapable of supporting combustion or respiration2 and consequently that atmospheric air is composed of two elastic fluids of different and opposite qualities4 ,as a proof of this important truth1 if we recombine these two elastic fluids1 which we have separately obtained in the above experiment1 viz4 the #db cubical inches of mephitis1 with the #h cubical inches of respirable air1 we reproduce an air precisely similar to that of the atmosphere1 and possessing nearly the same power of supporting combustion and respiration1 and of contributing to the calcination of metals4 ,although this experiment furnishes us with a very simple means of obtaining the two principal elastic fluids which compose our atmosphere1 separate from each other1 yet it does not give us an exact idea of the proportion in which these two enter into its composition3 ,for the attraction of mercury to the respirable part of the air1 or rather to its base1 is not sufficiently strong to overcome all the circumstances which oppose this union4 ,these obstacles are the mutual adhesion of the two constituent parts of the atmosphere for each other1 and the elective attraction which unites the base of vital air with caloric2 in consequence of these1 when the calcination ends1 or is at least carried as far as is possible1 in a determinate quantity of atmospheric air1 there still remains a portion of respirable air united to the mephitis1 which the mercury cannot separate4 ,i shall afterwards show1 that1 at least in our climate1 the atmospheric air is composed of respirable and mephitic airs1 in the proportion of #bg and #gc2 and ,i shall then discuss the causes of the uncertainty which still exists with respect to the exactness of that proportion4 ,since1 during the calcination of mercury1 air is decomposed1 and the base of its respirable part is fixed and combined with the mercury1 it follows1 from the principles already established1 that caloric and light must be disengaged during the process3 ,but the two following causes prevent us from being sensible of this taking place3 ,as the calcination lasts during several days1 the disengagement of caloric and light1 spread out in a considerable space of time1 becomes extremely small for each particular moment of that time1 so as not to be perceptible2 and1 in the next place1 the operation being carried on by means of fire in a furnace1 the heat produced by the calcination itself becomes confounded with that proceeding from the furnace4 ,i might add the respirable part of the air1 or rather its base1 in entering into combination with the mercury1 does not part with all the caloric which it contained1 but still retains a part of it after forming the new compound2 but the discussion of this point1 and its proofs from experiment1 do not belong to this part of our subject4 ,it is1 however1 easy to render this disengagement of caloric and light evident to the senses1 by causing the decomposition of air to take place in a more rapid manner4 ,and for this purpose1 iron is excellently adapted1 as it possesses a much stronger affinity for the base of respirable air than mercury4 ,the elegant experiment of ,mr ,ingenhouz1 upon the combustion of iron1 is well known4 ,take a piece of fine iron wire1 twisted into a spiral1 7,,bc1 ,plate ,,iv4 ,fig4 #ag47 fix one of its extremities ,b into the cork ,a1 adapted to the neck of the bottle ,,defg1 and fix to the other extremity of the wire ,c1 a small morsel of tinder4 ,matters being thus prepared1 fill the bottle ,,defg with air deprived of its mephitic part2 then light the tinder1 and introduce it quickly with the wire upon which it is fixed1 into the bottle which you stop up with the cork ,a1 as is shown in the figure 7#ag ,plate ,,iv47 ,the instant the tinder comes into contact with the vital air it begins to burn with great intensity2 and1 communicating the inflammation to the iron-wire1 it too takes fire1 and burns rapidly1 throwing out brilliant sparks1 which fall to the bottom of the vessel in rounded globules1 which become black in cooling1 but retain a degree of metallic splendour4 ,the iron thus burnt is more brittle even than glass1 and is easily reduced into powder1 and is still attractable by the magnet1 though not so powerfully as it was before combustion4 ,as ,mr ,ingenhouz has neither examined the change produced on iron1 nor upon the air by this operation1 ,i have repeated the experiment under different circumstances1 in an apparatus adapted to answer my particular views1 as follows4 ,having filled a bell-glass 7,a1 ,plate ,,iv4 ,fig4 #c47 of about six pints measure1 with pure air1 or the highly respirable part of air1 ,i transported this jar by means of a very flat vessel1 into a quicksilver bath in the bason ,,bc1 and ,i took care to render the surface of the mercury perfectly dry both within and without the jar with blotting paper4 ,i then provided a small capsule of china-ware ,d1 very flat and open1 in which ,i placed some small pieces of iron1 turned spirally1 and arranged in such a way as seemed most favourable for the combustion being communicated to every part4 ,to the end of one of these pieces of iron was fixed a small morsel of tinder1 to which was added about the sixteenth part of a grain of phosphorus1 and1 by raising the bell-glass a little1 the china capsule1 with its contents1 were introduced into the pure air4 ,i know that1 by this means1 some common air must mix with the pure air in the glass2 but this1 when it is done dexterously1 is so very trifling1 as not to injure the success of the experiment4 ,this being done1 a part of the air is sucked out from the bell-glass1 by means of a syphon ,,ghi1 so as to raise the mercury within the glass to ,,ef2 and1 to prevent the mercury from getting into the syphon1 a small piece of paper is twisted round its extremity4 ,in sucking out the air1 if the motion of the lungs only be used1 we cannot make the mercury rise above an inch or an inch and a half2 but1 by properly using the muscles of the mouth1 we can1 without difficulty1 cause it to rise six or seven inches4 ,i next took an iron wire1 7,,mn1 ,plate ,,iv4 ,fig4 #af47 properly bent for the purpose1 and making it red hot in the fire1 passed it through the mercury into the receiver1 and brought it in contact with the small piece of phosphorus attached to the tinder4 ,the phosphorus instantly takes fire1 which communicates to the tinder1 and from that to the iron4 ,when the pieces have been properly arranged1 the whole iron burns1 even to the last particle1 throwing out a white brilliant light similar to that of ,chinese fireworks4 ,the great heat produced by this combustion melts the iron into round globules of different sizes1 most of which fall into the ,china cup2 but some are thrown out of it1 and swim upon the surface of the mercury4 ,at the beginning of the combustion1 there is a slight augmentation in the volume of the air in the bell-glass1 from the dilatation caused by the heat2 but1 presently afterwards1 a rapid diminution of the air takes place1 and the mercury rises in the glass2 insomuch that1 when the quantity of iron is sufficient1 and the air operated upon is very pure1 almost the whole air employed is absorbed4 ,it is proper to remark in this place1 that1 unless in making experiments for the purpose of discovery1 it is better to be contented with burning a moderate quantity of iron2 for1 when this experiment is pushed too far1 so as to absorb much of the air1 the cup ,d1 which floats upon the quicksilver1 approaches too near the bottom of the bell-glass2 and the great heat produced1 which is followed by a very sudden cooling1 occasioned by the contact of the cold mercury1 is apt to break the glass4 ,in which case1 the sudden fall of the column of mercury1 which happens the moment the least flaw is produced in the glass1 causes such a wave1 as throws a great part of the quicksilver from the bason4 ,to avoid this inconvenience1 and to ensure success to the experiment1 one gross and a half of iron is sufficient to burn in a bell-glass1 which holds about eight pints of air4 ,the glass ought likewise to be strong1 that it may be able to bear the weight of the column of mercury which it has to support4 ,by this experiment1 it is not possible to determine1 at one time1 both the additional weight acquired by the iron1 and the changes which have taken place in the air4 ,if it is wished to ascertain what additional weight has been gained by the iron1 and the proportion between that and the air absorbed1 we must carefully mark upon the bell-glass1 with a diamond1 the height of the mercury1 both before and after the experiment#i4 ,after this1 the syphon 7,,gh1 ,pl4 ,,iv4 fig4 #c47 guarded1 as before1 with a bit of paper1 to prevent its filling with mercury1 is to be introduced under the bell-glass1 having the thumb placed upon the extremity1 ,g1 of the syphon1 to regulate the passage of the air2 and by this means the air is gradually admitted1 so as to let the mercury fall to its level4 ,this being done1 the bell-glass is to be carefully removed1 the globules of melted iron contained in the cup1 and those which have been scattered about1 and swim upon the mercury1 are to be accurately collected1 and the whole is to be weighed4 ,the iron will be found in that state called martial ethiops by the old chemists1 possessing a degree of metallic brilliancy1 very friable1 and readily reducible into powder1 under the hammer1 or with a pestle and mortar4 ,if the experiment has succeeded well1 from #ajj grains of iron will be obtained #ace or #acf grains of ethiops1 which is an augmentation of #ce per cent4 ,if all the attention has been paid to this experiment which it deserves1 the air will be found diminished in weight exactly equal to what the iron has gained4 ,having therefore burnt #ajj grains of iron1 which has acquired an additional weight of #ce grains1 the diminution of air will be found exactly #gj cubical inches2 and it will be found1 in the sequel1 that the weight of vital air is pretty nearly half a grain for each cubical inch2 so that1 in effect1 the augmentation of weight in the one exactly coincides with the loss of it in the other4 ,i shall observe here1 once for all1 that1 in every experiment of this kind1 the pressure and temperature of the air1 both before and after the experiment1 must be reduced1 by calculation1 to a common standard of #aj 7#ed4e7 of the thermometer1 and #bh inches of the barometer4 ,towards the end of this work1 the manner of performing this very necessary reduction will be found accurately detailed4 ,if it be required to examine the nature of the air which remains after this experiment1 we must operate in a somewhat different manner4 ,after the combustion is finished1 and the vessels have cooled1 we first take out the cup1 and the burnt iron1 by introducing the hand through the quicksilver1 under the bell-glass2 we next introduce some solution of potash1 or caustic alkali1 or of the sulphuret of potash1 or such other substance as is judged proper for examining their action upon the residuum of air4 ,i shall1 in the sequel1 give an account of these methods of analysing air1 when ,i have explained the nature of these different substances1 which are only here in a manner accidentally mentioned4 ,after this examination1 so much water must be let into the glass as will displace the quicksilver1 and then1 by means of a shallow dish placed below the bell-glass1 it is to be removed into the common water pneumato-chemical apparatus1 where the air remaining may be examined at large1 and with great facility4 ,when very soft and very pure iron has been employed in this experiment1 and1 if the combustion has been performed in the purest respirable or vital air1 free from all admixture of the noxious or mephitic part1 the air which remains after the combustion will be found as pure as it was before2 but it is difficult to find iron entirely free from a small portion of charry matter1 which is chiefly abundant in steel4 ,it is likewise exceedingly difficult to procure the pure air perfectly free from some admixture of mephitis1 with which it is almost always contaminated2 but this species of noxious air does not1 in the smallest degree1 disturb the result of the experiment1 as it is always found at the end exactly in the same proportion as at the beginning4 ,i mentioned before1 that we have two ways of determining the constituent parts of atmospheric air1 the method of analysis1 and that by synthesis4 ,the calcination of mercury has furnished us with an example of each of these methods1 since1 after having robbed the respirable part of its base1 by means of the mercury1 we have restored it1 so as to recompose an air precisely similar to that of the atmosphere4 ,but we can equally accomplish this synthetic composition of atmospheric air1 by borrowing the materials of which it is composed from different kingdoms of nature4 ,we shall see hereafter that1 when animal substances are dissolved in the nitric acid1 a great quantity of gas is disengaged1 which extinguishes light1 and is unfit for animal respiration1 being exactly similar to the noxious or mephitic part of atmospheric air4 ,and1 if we take #gc parts1 by weight1 of this elastic fluid1 and mix it with #bg parts of highly respirable air1 procured from calcined mercury1 we will form an elastic fluid precisely similar to atmospheric air in all its properties4 ,there are many other methods of separating the respirable from the noxious part of the atmospheric air1 which cannot be taken notice of in this part1 without anticipating information1 which properly belongs to the subsequent chapters4 ,the experiments already adduced may suffice for an elementary treatise2 and1 in matters of this nature1 the choice of our evidences is of far greater consequence than their number4 ,i shall close this article1 by pointing out the property which atmospheric air1 and all the known gasses1 possess of dissolving water1 which is of great consequence to be attended to in all experiments of this nature4 ,mr ,saussure found1 by experiment1 that a cubical foot of atmospheric air is capable of holding #ab grains of water in solution3 ,other gasses1 as the carbonic acid1 appear capable of dissolving a greater quantity2 but experiments are still wanting by which to determine their several proportions4 ,this water1 held in solution by gasses1 gives rise to particular phenomena in many experiments1 which require great attention1 and which has frequently proved the source of great errors to chemists in determining the results of their experiments4 ,,footnotes3 #i ,it will likewise be necessary to take care that the air contained in the glass1 both before and after the experiment1 be reduced to a common temperature and pressure1 otherwise the results of the following calculations will be fallacious4--,e4 ,,chap4 ,,iv4 ,nomenclature of the several ,constituent ,parts of ,atmospheric ,air4 ,hitherto ,i have been obliged to make use of circumlocution1 to express the nature of the several substances which constitute our atmosphere1 having provisionally used the terms of respirable and noxious1 or non-respirable parts of the air4 ,but the investigations ,i mean to undertake require a more direct mode of expression2 and1 having now endeavoured to give simple and distinct ideas of the different substances which enter into the composition of the atmosphere1 ,i shall henceforth express these ideas by words equally simple4 ,the temperature of our earth being very near to that at which water becomes solid1 and reciprocally changes from solid to fluid1 and as this phenomenon takes place frequently under our observation1 it has very naturally followed1 that1 in the languages of at least every climate subjected to any degree of winter1 a term has been used for signifying water in the state of solidity1 when deprived of its caloric4 ,the same1 however1 has not been found necessary with respect to water reduced to the state of vapour by an additional dose of caloric2 since those persons who do not make a particular study of objects of this kind1 are still ignorant that water1 when in a temperature only a little above the boiling heat1 is changed into an elastic ariform fluid1 susceptible1 like all other gasses1 of being received and contained in vessels1 and preserving its gasseous form so long as it remains at the temperature of #hj 7#bab71 and under a pressure not exceeding #bh inches of the mercurial barometer4 ,as this phenomenon has not been generally observed1 no language has used a particular term for expressing water in this state#aj2 and the same thing occurs with all fluids1 and all substances1 which do not evaporate in the common temperature1 and under the usual pressure of our atmosphere4 ,for similar reasons1 names have not been given to the liquid or concrete states of most of the ariform fluids3 ,these were not known to arise from the combination of caloric with certain bases2 and1 as they had not been seen either in the liquid or solid states1 their existence1 under these forms1 was even unknown to natural philosophers4 ,we have not pretended to make any alteration upon such terms as are sanctified by ancient custom2 and1 therefore1 continue to use the words water and ice in their common acceptation3 ,we likewise retain the word air1 to express that collection of elastic fluids which composes our atmosphere2 but we have not thought it necessary to preserve the same respect for modern terms1 adopted by latter philosophers1 having considered ourselves as at liberty to reject such as appeared liable to occasion erroneous ideas of the substances they are meant to express1 and either to substitute new terms1 or to employ the old ones1 after modifying them in such a manner as to convey more determinate ideas4 ,new words have been drawn1 chiefly from the ,greek language1 in such a manner as to make their etymology convey some idea of what was meant to be represented2 and these we have always endeavoured to make short1 and of such a nature as to be changeable into adjectives and verbs4 ,following these principles1 we have1 after ,mr ,macquer's example1 retained the term gas1 employed by ,vanhelmont1 having arranged the numerous class of elastic ariform fluids under that name1 excepting only atmospheric air4 ,gas1 therefore1 in our nomenclature1 becomes a generic term1 expressing the fullest degree of saturation in any body with caloric2 being1 in fact1 a term expressive of a mode of existence4 ,to distinguish each species of gas1 we employ a second term from the name of the base1 which1 saturated with caloric1 forms each particular gas4 ,thus1 we name water combined to saturation with caloric1 so as to form an elastic fluid1 aqueous gas2 ether1 combined in the same manner1 etherial gas2 the combination of alkohol with caloric1 becomes alkoholic gas2 and1 following the same principles1 we have muriatic acid gas1 ammoniacal gas1 and so on of every substance susceptible of being combined with caloric1 in such a manner as to assume the gasseous or elastic ariform state4 ,we have already seen1 that the atmospheric air is composed of two gasses1 or ariform fluids1 one of which is capable1 by respiration1 of contributing to animal life1 and in which metals are calcinable1 and combustible bodies may burn2 the other1 on the contrary1 is endowed with directly opposite qualities2 it cannot be breathed by animals1 neither will it admit of the combustion of inflammable bodies1 nor of the calcination of metals4 ,we have given to the base of the former1 or respirable portion of the air1 the name of oxygen1 from ,greek3 oxys acidum1 and ,greek3 geinomas1 gignor2 because1 in reality1 one of the most general properties of this base is to form acids1 by combining with many different substances4 ,the union of this base with caloric we term oxygen gas1 which is the same with what was formerly called pure1 or vital air4 ,the weight of this gas1 at the temperature of #aj 7#ed4ej71 and under a pressure equal to #bh inches of the barometer1 is half a grain for each cubical inch1 or one ounce and a half to each cubical foot4 ,the chemical properties of the noxious portion of atmospheric air being hitherto but little known1 we have been satisfied to derive the name of its base from its known quality of killing such animals as are forced to breathe it1 giving it the name of azote1 from the ,greek privitive particle ,greek3 a and ,greek3 xa1 vita2 hence the name of the noxious part of atmospheric air is azotic gas2 the weight of which1 in the same temperature1 and under the same pressure1 is #a oz4 #b gros and #dh grs4 to the cubical foot1 or #j4dddd of a grain to the cubical inch4 ,we cannot deny that this name appears somewhat extraordinary2 but this must be the case with all new terms1 which cannot be expected to become familiar until they have been some time in use4 ,we long endeavoured to find a more proper designation without success2 it was at first proposed to call it alkaligen gas1 as1 from the experiments of ,mr ,berthollet1 it appears to enter into the composition of ammoniac1 or volatile alkali2 but then1 we have as yet no proof of its making one of the constituent elements of the other alkalies2 beside1 it is proved to compose a part of the nitric acid1 which gives as good reason to have called it nitrigen4 ,for these reasons1 finding it necessary to reject any name upon systematic principles1 we have considered that we run no risk of mistake in adopting the terms of azote1 and azotic gas1 which only express a matter of fact1 or that property which it possesses1 of depriving such animals as breathe it of their lives4 ,i should anticipate subjects more properly reserved for the subsequent chapters1 were ,i in this place to enter upon the nomenclature of the several species of gasses3 ,it is sufficient1 in this part of the work1 to establish the principles upon which their denominations are founded4 ,the principal merit of the nomenclature we have adopted is1 that1 when once the simple elementary substance is distinguished by an appropriate term1 the names of all its compounds derive readily1 and necessarily1 from this first denomination4 ,,footnotes3 #aj ,in ,english1 the word steam is exclusively appropriated to water in the state of vapour4 ,e4 ,,chap4 ,v4 ,of the ,decomposition of ,oxygen ,gas by ,sulphur1 ,phosphorus1 and ,charcoal--and of the ,formation of ,acids in general4 ,in performing experiments1 it is a necessary principle1 which ought never to be deviated from1 that they be simplified as much as possible1 and that every circumstance capable of rendering their results complicated be carefully removed4 ,wherefore1 in the experiments which form the object of this chapter1 we have never employed atmospheric air1 which is not a simple substance4 ,it is true1 that the azotic gas1 which forms a part of its mixture1 appears to be merely passive during combustion and calcination2 but1 besides that it retards these operations very considerably1 we are not certain but it may even alter their results in some circumstances2 for which reason1 ,i have thought it necessary to remove even this possible cause of doubt1 by only making use of pure oxygen gas in the following experiments1 which show the effects produced by combustion in that gas2 and ,i shall advert to such differences as take place in the results of these1 when the oxygen gas1 or pure vital air1 is mixed1 in different proportions1 with azotic gas4 ,having filled a bell-glass 7,a4 ,pl4 iv4 fig4 #c71 of between five and six pints measure1 with oxygen gas1 ,i removed it from the water trough1 where it was filled1 into the quicksilver bath1 by means of a shallow glass dish slipped underneath1 and having dried the mercury1 ,i introduced #fa-a_/d grains of ,kunkel's phosphorus in two little ,china cups1 like that represented at ,d1 fig4 #c4 under the glass ,a2 and that ,i might set fire to each of the portions of phosphorus separately1 and to prevent the one from catching fire from the other1 one of the dishes was covered with a piece of flat glass4 ,i next raised the quicksilver in the bell-glass up to ,e ,f1 by sucking out a sufficient portion of the gas by means of the syphon ,g ,h ,i4 ,after this1 by means of the crooked iron wire 7fig4 #af471 made red hot1 ,i set fire to the two portions of phosphorus successively1 first burning that portion which was not covered with the piece of glass4 ,the combustion was extremely rapid1 attended with a very brilliant flame1 and considerable disengagement of light and heat4 ,in consequence of the great heat induced1 the gas was at first much dilated1 but soon after the mercury returned to its level1 and a considerable absorption of gas took place2 at the same time1 the whole inside of the glass became covered with white light flakes of concrete phosphoric acid4 ,at the beginning of the experiment1 the quantity of oxygen gas1 reduced1 as above directed1 to a common standard1 amounted to #afb cubical inches2 and1 after the combustion was finished1 only #bc-a_/d cubical inches1 likewise reduced to the standard1 remained2 so that the quantity of oxygen gas absorbed during the combustion was #ach-c_/d cubical inches1 equal to #fi4cge grains4 ,a part of the phosphorus remained unconsumed in the bottom of the cups1 which being washed on purpose to separate the acid1 weighed about #af-a_/d grains2 so that about #de grains of phosphorus had been burned3 ,but1 as it is hardly possible to avoid an error of one or two grains1 ,i leave the quantity so far qualified4 ,hence1 as nearly #de grains of phosphorus had1 in this experiment1 united with #fi4cge grains of oxygen1 and as no gravitating matter could have escaped through the glass1 we have a right to conclude1 that the weight of the substance resulting from the combustion in form of white flakes1 must equal that of the phosphorus and oxygen employed1 which amounts to #aad4cge grains4 ,and we shall presently find1 that these flakes consisted entirely of a solid or concrete acid4 ,when we reduce these weights to hundredth parts1 it will be found1 that #ajj parts of phosphorus require #aed parts of oxygen for saturation1 and that this combination will produce #bed parts of concrete phosphoric acid1 in form of white fleecy flakes4 ,this experiment proves1 in the most convincing manner1 that1 at a certain degree of temperature1 oxygen possesses a stronger elective attraction1 or affinity1 for phosphorus than for caloric2 that1 in consequence of this1 the phosphorus attracts the base of oxygen gas from the caloric1 which1 being set free1 spreads itself over the surrounding bodies4 ,but1 though this experiment be so far perfectly conclusive1 it is not sufficiently rigorous1 as1 in the apparatus described1 it is impossible to ascertain the weight of the flakes of concrete acid which are formed2 we can therefore only determine this by calculating the weights of oxygen and phosphorus employed2 but as1 in physics1 and in chemistry1 it is not allowable to suppose what is capable of being ascertained by direct experiment1 ,i thought it necessary to rep at this experiment1 as follows1 upon a larger scale1 and by means of a different apparatus4 ,i took a large glass baloon 7,a4 ,pl4 iv4 fig4 #d47 with an opening three inches diameter1 to which was fitted a crystal stopper ground with emery1 and pierced with two holes for the tubes yyy1 xxx4 ,before shutting the baloon with its stopper1 ,i introduced the support ,,bc1 surmounted by the china cup ,d1 containing #aej grs4 of phosphorus2 the stopper was then fitted to the opening of the baloon1 luted with fat lute1 and covered with slips of linen spread with quick-lime and white of eggs3 ,when the lute was perfectly dry1 the weight of the whole apparatus was determined to within a grain1 or a grain and a half4 ,i next exhausted the baloon1 by means of an air pump applied to the tube ,,xxx1 and then introduced oxygen gas by means of the tube yyy1 having a stop cock adapted to it4 ,this kind of experiment is most readily and most exactly performed by means of the hydro-pneumatic machine described by ,mr ,meusnier and me in the ,memoirs of the ,academy for #aghb1 pag4 #dff4 and explained in the latter part of this work1 with several important additions and corrections since made to it by ,mr ,meusnier4 ,with this instrument we can readily ascertain1 in the most exact manner1 both the quantity of oxygen gas introduced into the baloon1 and the quantity consumed during the course of the experiment4 ,when all things were properly disposed1 ,i set fire to the phosphorus with a burning glass4 ,the combustion was extremely rapid1 accompanied with a bright flame1 and much heat2 as the operation went on1 large quantities of white flakes attached themselves to the inner surface of the baloon1 so that at last it was rendered quite opake4 ,the quantity of these flakes at last became so abundant1 that1 although fresh oxygen gas was continually supplied1 which ought to have supported the combustion1 yet the phosphorus was soon extinguished4 ,having allowed the apparatus to cool completely1 ,i first ascertained the quantity of oxygen gas employed1 and weighed the baloon accurately1 before it was opened4 ,i next washed1 dried1 and weighed the small quantity of phosphorus remaining in the cup1 on purpose to determine the whole quantity of phosphorus consumed in the experiment2 this residuum of the phosphorus was of a yellow ochrey colour4 ,it is evident1 that by these several precautions1 ,i could easily determine1 #ast1 the weight of the phosphorus consumed2 #b;d1 the weight of the flakes produced by the combustion2 and1 #c;d1 the weight of the oxygen which had combined with the phosphorus4 ,this experiment gave very nearly the same results with the former1 as it proved that the phosphorus1 during its combustion1 had absorbed a little more than one and a half its weight of oxygen2 and ,i learned with more certainty1 that the weight of the new substance1 produced in the experiment1 exactly equalled the sum of the weights of the phosphorus consumed1 and oxygen absorbed1 which indeed was easily determinable a priori4 ,if the oxygen gas employed be pure1 the residuum after combustion is as pure as the gas employed2 this proves that nothing escapes from the phosphorus1 capable of altering the purity of the oxygen gas1 and that the only action of the phosphorus is to separate the oxygen from the caloric1 with which it was before united4 ,i mentioned above1 that when any combustible body is burnt in a hollow sphere of ice1 or in an apparatus properly constructed upon that principle1 the quantity of ice melted during the combustion is an exact measure of the quantity of caloric disengaged4 ,upon this head1 the memoir given by ,m4 de la ,place and me1 ,a4 #aghj1 p4 #cee1 may be consulted4 ,having submitted the combustion of phosphorus to this trial1 we found that one pound of phosphorus melted a little more than #ajj pounds of ice during its combustion4 ,the combustion of phosphorus succeeds equally well in atmospheric air as in oxygen gas1 with this difference1 that the combustion is vastly slower1 being retarded by the large proportion of azotic gas mixed with the oxygen gas1 and that only about one-fifth part of the air employed is absorbed1 because as the oxygen gas only is absorbed1 the proportion of the azotic gas becomes so great toward the close of the experiment1 as to put an end to the combustion4 ,i have already shown1 that phosphorus is changed by combustion into an extremely light1 white1 flakey matter2 and its properties are entirely altered by this transformation3 ,from being insoluble in water1 it becomes not only soluble1 but so greedy of moisture1 as to attract the humidity of the air with astonishing rapidity2 by this means it is converted into a liquid1 considerably more dense1 and of more specific gravity than water4 ,in the state of phosphorus before combustion1 it had scarcely any sensible taste1 by its union with oxygen it acquires an extremely sharp and sour taste3 in a word1 from one of the class of combustible bodies1 it is changed into an incombustible substance1 and becomes one of those bodies called acids4 ,this property of a combustible substance to be converted into an acid1 by the addition of oxygen1 we shall presently find belongs to a great number of bodies3 ,wherefore1 strict logic requires that we should adopt a common term for indicating all these operations which produce analogous results2 this is the true way to simplify the study of science1 as it would be quite impossible to bear all its specifical details in the memory1 if they were not classically arranged4 ,for this reason1 we shall distinguish this conversion of phosphorus into an acid1 by its union with oxygen1 and in general every combination of oxygen with a combustible substance1 by the term of oxygenation3 from which ,i shall adopt the verb to oxygenate1 and of consequence shall say1 that in oxygenating phosphorus we convert it into an acid4 ,sulphur is likewise a combustible body1 or1 in other words1 it is a body which possesses the power of decomposing oxygen gas1 by attracting the oxygen from the caloric with which it was combined4 ,this can very easily be proved1 by means of experiments quite similar to those we have given with phosphorus2 but it is necessary to premise1 that in these operations with sulphur1 the same accuracy of result is not to be expected as with phosphorus2 because the acid which is formed by the combustion of sulphur is difficultly condensible1 and because sulphur burns with more difficulty1 and is soluble in the different gasses4 ,but ,i can safely assert1 from my own experiments1 that sulphur in burning absorbs oxygen gas2 that the resulting acid is considerably heavier than the sulphur burnt2 that its weight is equal to the sum of the weights of the sulphur which has been burnt1 and of the oxygen absorbed2 and1 lastly that this acid is weighty1 incombustible1 and miscible with water in all proportions3 ,the only uncertainty remaining upon this head1 is with regard to the proportions of sulphur and of oxygen which enter into the composition of the acid4 ,charcoal1 which1 from all our present knowledge regarding it1 must be considered as a simple combustible body1 has likewise the property of decomposing oxygen gas1 by absorbing its base from the caloric3 ,but the acid resulting from this combustion does not condense in the common temperature2 under the pressure of our atmosphere1 it remains in the state of gas1 and requires a large proportion of water to combine with or be dissolved in4 ,this acid has1 however1 all the known properties of other acids1 though in a weaker degree1 and combines1 like them1 with all the bases which are susceptible of forming neutral salts4 ,the combustion of charcoal in oxygen gas1 may be effected like that of phosphorus in the bell-glass1 7,a4 ,pl4 ,,iv4 fig4 #c47 placed over mercury3 but1 as the heat of red hot iron is not sufficient to set fire to the charcoal1 we must add a small morsel of tinder1 with a minute particle of phosphorus1 in the same manner as directed in the experiment for the combustion of iron4 ,a detailed account of this experiment will be found in the memoirs of the academy for #agha1 p4 #ddh4 ,by that experiment it appears1 that #bh parts by weight of charcoal require #gb parts of oxygen for saturation1 and that the ariform acid produced is precisely equal in weight to the sum of the weights of the charcoal and oxygen gas employed4 ,this ariform acid was called fixed or fixable air by the chemists who first discovered it2 they did not then know whether it was air resembling that of the atmosphere1 or some other elastic fluid1 vitiated and corrupted by combustion2 but since it is now ascertained to be an acid1 formed like all others by the oxygenation of its peculiar base1 it is obvious that the name of fixed air is quite ineligible#aa4 ,by burning charcoal in the apparatus mentioned p4 #fj1 ,mr de la ,place and ,i found that one lib4 of charcoal melted #if libs4 #f oz4 of ice2 that1 during the combustion1 #b libs4 #i oz4 #a gros4 #aj grs4 of oxygen were absorbed1 and that #c libs4 #i oz4 #a gros4 #aj grs4 of acid gas were formed4 ,this gas weighs #j4fie parts of a grain for each cubical inch1 in the common standard temperature and pressure mentioned above1 so that #cd1bdb cubical inches of acid gas are produced by the combustion of one pound of charcoal4 ,i might multiply these experiments1 and show by a numerous succession of facts1 that all acids are formed by the combustion of certain substances2 but ,i am prevented from doing so in place1 by the plan which ,i have laid down1 of proceeding only from facts already ascertained1 to such as are unknown1 and of drawing my examples only from circumstances already explained4 ,in the mean time1 however1 the three examples above cited may suffice for giving a clear and accurate conception of the manner in which acids are formed4 ,by these it may be clearly seen1 that oxygen is an element common to them all1 which constitutes their acidity2 and that they differ from each other1 according to the nature of the oxygenated or acidified substance4 ,we must therefore1 in every acid1 carefully distinguish between the acidifiable1 base1 which ,mr de ,morveau calls the radical1 and the acidifiing principle or oxygen4 ,,footnotes3 #aa ,it may be proper to remark1 though here omitted by the author1 that1 in conformity with the general principles of the new nomenclature1 this acid is by ,mr ,lavoisier and his coleagues called the carbonic acid1 and when in the ariform state carbonic acid gas4 ,e4 ,,chap4 ,,vi4 ,of the ,nomenclature of ,acids in general1 and particularly of those drawn from ,nitre and ,sea-,salt4 ,it becomes extremely easy1 from the principles laid down in the preceding chapter1 to establish a systematic nomenclature for the acids3 ,the word acid1 being used as a generic term1 each acid falls to be distinguished in language1 as in nature1 by the name of its base or radical4 ,thus1 we give the generic name of acids to the products of the combustion or oxygenation of phosphorus1 of sulphur1 and of charcoal2 and these products are respectively named1 the phosphoric acid1 the sulphuric acid1 and the carbonic acid4 ,there is however1 a remarkable circumstance in the oxygenation of combustible bodies1 and of a part of such bodies as are convertible into acids1 that they are susceptible of different degrees of saturation with oxygen1 and that the resulting acids1 though formed by the union of the same elements1 are possessed of different properties1 depending upon that difference of proportion4 ,of this1 the phosphoric acid1 and more especially the sulphuric1 furnishes us with examples4 ,when sulphur is combined with a small proportion of oxygen1 it forms1 in this first or lower degree of oxygenation1 a volatile acid1 having a penetrating odour1 and possessed of very particular qualities4 ,by a larger proportion of oxygen1 it is changed into a fixed1 heavy acid1 without any odour1 and which1 by combination with other bodies1 gives products quite different from those furnished by the former4 ,in this instance1 the principles of our nomenclature seem to fail2 and it seems difficult to derive such terms from the name of the acidifiable base1 as shall distinctly express these two degrees of saturation1 or oxygenation1 without circumlocution4 ,by reflection1 however1 upon the subject1 or perhaps rather from the necessity of the case1 we have thought it allowable to express these varieties in the oxygenation of the acids1 by simply varying the termination of their specific names4 ,the volatile acid produced from sulphur was anciently known to ,stahl under the name of sulphurous acid#ab4 ,we have preserved that term for this acid from sulphur under-saturated with oxygen2 and distinguish the other1 or completely saturated or oxygenated acid1 by the name of sulphuric acid4 ,we shall therefore say1 in this new chemical language1 that sulphur1 in combining with oxygen1 is susceptible of two degrees of saturation2 that the first1 or lesser degree1 constitutes sulphurous acid1 which is volatile and penetrating2 whilst the second1 or higher degree of saturation1 produces sulphuric acid1 which is fixed and inodorous4 ,we shall adopt this difference of termination for all the acids which assume several degrees of saturation4 ,hence we have a phosphorous and a phosphoric acid1 an acetous and an acetic acid2 and so on1 for others in similar circumstances4 ,this part of chemical science would have been extremely simple1 and the nomenclature of the acids would not have been at all perplexed1 as it is now in the old nomenclature1 if the base or radical of each acid had been known when the acid itself was discovered4 ,thus1 for instance1 phosphorus being a known substance before the discovery of its acid1 this latter was rightly distinguished by a term drawn from the name of its acidifiable base4 ,but when1 on the contrary1 an acid happened to be discovered before its base1 or rather1 when the acidifiable base from which it was formed remained unknown1 names were adopted for the two1 which have not the smallest connection2 and thus1 not only the memory became burthened with useless appellations1 but even the minds of students1 nay even of experienced chemists1 became filled with false ideas1 which time and reflection alone is capable of eradicating4 ,we may give an instance of this confusion with respect to the acid sulphur3 ,the former chemists having procured this acid from the vitriol of iron1 gave it the name of the vitriolic acid from the name of the substance which produced it2 and they were then ignorant that the acid procured from sulphur by combustion was exactly the same4 ,the same thing happened with the ariform acid formerly called fixed air2 it not being known that this acid was the result of combining charcoal with oxygen1 a variety of denominations have been given to it1 not one of which conveys just ideas of its nature or origin4 ,we have found it extremely easy to correct and modify the ancient language with respect to these acids proceeding from known bases1 having converted the name of vitriolic acid into that of sulphuric1 and the name of fixed air into that of carbonic acid2 but it is impossible to follow this plan with the acids whose bases are still unknown2 with these we have been obliged to use a contrary plan1 and1 instead of forming the name of the acid from that of its base1 have been forced to denominate the unknown base from the name of the known acid1 as happens in the case of the acid which is procured from sea salt4 ,to disengage this acid from the alkaline base with which it is combined1 we have only to pour sulphuric acid upon sea-salt1 immediately a brisk effervescence takes place1 white vapours arise1 of a very penetrating odour1 and1 by only gently heating the mixture1 all the acid is driven off4 ,as1 in the common temperature and pressure of our atmosphere1 this acid is naturally in the state of gas1 we must use particular precautions for retaining it in proper vessels4 ,for small experiments1 the most simple and most commodious apparatus consists of a small retort ,g1 7,pl4 ,v4 ,fig4 #e471 into which the sea-salt is introduced1 well dried#ac1 we then pour on some concentrated sulphuric acid1 and immediately introduce the beak of the retort under little jars or bell-glasses ,a1 7same ,plate and ,fig471 previously filled with quicksilver4 ,in proportion as the acid gas is disengaged1 it passes into the jar1 and gets to the top of the quicksilver1 which it displaces4 ,when the disengagement of the gas slackens1 a gentle heat is applied to the retort1 and gradually increased till nothing more passes over4 ,this acid gas has a very strong affinity with water1 which absorbs an enormous quantity of it1 as is proved by introducing a very thin layer of water into the glass which contains the gas2 for1 in an instant1 the whole acid gas disappears1 and combines with the water4 ,this latter circumstance is taken advantage of in laboratories and manufactures1 on purpose to obtain the acid of sea-salt in a liquid form2 and for this purpose the apparatus 7,pl4 ,,iv4 ,fig4 #a47 is employed4 ,it consists1 #ast1 of a tubulated retort ,a1 into which the sea-salt1 and after it the sulphuric acid1 are introduced through the opening ,h2 #b;d1 of the baloon or recipient c1 b1 intended for containing the small quantity of liquid which passes over during the process2 and1 #c;d1 of a set of bottles1 with two mouths1 ,l1 ,l1 ,l1 ,l1 half filled with water1 intended for absorbing the gas disengaged by the distillation4 ,this apparatus will be more amply described in the latter part of this work4 ,although we have not yet been able1 either to compose or to decompound this acid of sea-salt1 we cannot have the smallest doubt that it1 like all other acids1 is composed by the union of oxygen with an acidifiable base4 ,we have therefore called this unknown substance the muriatic base1 or muriatic radical1 deriving this name1 after the example of ,mr ,bergman and ,mr de ,morveau1 from the ,latin word muria1 which was anciently used to signify sea-salt4 ,thus1 without being able exactly to determine the component parts of muriatic acid1 we design1 by that term1 a volatile acid1 which retains the form of gas in the common temperature and pressure of our atmosphere1 which combines with great facility1 and in great quantity1 with water1 and whose acidifiable base adheres so very intimately with oxygen1 that no method has hitherto been devised for separating them4 ,if ever this acidifiable base of the muriatic acid is discovered to be a known substance1 though now unknown in that capacity1 it will be requisite to change its present denomination for one analogous with that of its base4 ,in common with sulphuric acid1 and several other acids1 the muriatic is capable of different degrees of oxygenation2 but the excess of oxygen produces quite contrary effects upon it from what the same circumstance produces upon the acid of sulphur4 ,the lower degree of oxygenation converts sulphur into a volatile gasseous acid1 which only mixes in small proportions with water1 whilst a higher oxygenation forms an acid possessing much stronger acid properties1 which is very fixed and cannot remain in the state of gas but in a very high temperature1 which has no smell1 and which mixes in large proportion with water4 ,with muriatic acid1 the direct reverse takes place2 an additional saturation with oxygen renders it more volatile1 of a more penetrating odour1 less miscible with water1 and diminishes its acid properties4 ,we were at first inclined to have denominated these two degrees of saturation in the same manner as we had done with the acid of sulphur1 calling the less oxygenated muriatous acid1 and that which is more saturated with oxygen muriatic acid3 ,but1 as this latter gives very particular results in its combinations1 and as nothing analogous to it is yet known in chemistry1 we have left the name of muriatic acid to the less saturated1 and give the latter the more compounded appellation of oxygenated muriatic acid4 ,although the base or radical of the acid which is extracted from nitre or saltpetre be better known1 we have judged proper only to modify its name in the same manner with that of the muriatic acid4 ,it is drawn from nitre1 by the intervention of sulphuric acid1 by a process similar to that described for extracting the muriatic acid1 and by means of the same apparatus 7,pl4 ,,iv4 ,fig4 #a474 ,in proportion as the acid passes over1 it is in part condensed in the baloon or recipient1 and the rest is absorbed by the water contained in the bottles ,l1,l1,l1,l2 the water becomes first green1 then blue1 and at last yellow1 in proportion to the concentration of the acid4 ,during this operation1 a large quantity of oxygen gas1 mixed with a small proportion of azotic gas1 is disengaged4 ,this acid1 like all others1 is composed of oxygen1 united to an acidifiable base1 and is even the first acid in which the existence of oxygen was well ascertained4 ,its two constituent elements are but weakly united1 and are easily separated1 by presenting any substance with which oxygen has a stronger affinity than with the acidifiable base peculiar to this acid4 ,by some experiments of this kind1 it was first discovered that azote1 or the base of mephitis or azotic gas1 constituted its acidifiable base or radical2 and consequently that the acid of nitre was really an azotic acid1 having azote for its base1 combined with oxygen4 ,for these reasons1 that we might be consistent with our principles1 it appeared necessary1 either to call the acid by the name of azotic1 or to name the base nitric radical2 but from either of these we were dissuaded1 by the following considerations4 ,in the first place1 it seemed difficult to change the name of nitre or saltpetre1 which has been universally adopted in society1 in manufactures1 and in chemistry2 and1 on the other hand1 azote having been discovered by ,mr ,berthollet to be the base of volatile alkali1 or ammoniac1 as well as of this acid1 we thought it improper to call it nitric radical4 ,we have therefore continued the term of azote to the base of that part of atmospheric air which is likewise the nitric and ammoniacal radical2 and we have named the acid of nitre1 in its lower and higher degrees of oxygenation1 nitrous acid in the former1 and nitric acid in the latter state2 thus preserving its former appellation properly modified4 ,several very respectable chemists have disapproved of this deference for the old terms1 and wished us to have persevered in perfecting a new chemical language1 without paying any respect for ancient usage2 so that1 by thus steering a kind of middle course1 we have exposed ourselves to the censures of one sect of chemists1 and to the expostulations of the opposite party4 ,the acid of nitre is susceptible of assuming a great number of separate states1 depending upon its degree of oxygenation1 or upon the proportions in which azote and oxygen enter into its composition4 ,by a first or lowest degree of oxygenation1 it forms a particular species of gas1 which we shall continue to name nitrous gas2 this is composed nearly of two parts1 by weight1 of oxygen combined with one part of azote2 and in this state it is not miscible with water4 ,in this gas1 the azote is by no means saturated with oxygen1 but1 on the contrary1 has still a very great affinity for that element1 and even attracts it from atmospheric air1 immediately upon getting into contact with it4 ,this combination of nitrous gas with atmospheric air has even become one of the methods for determining the quantity of oxygen contained in air1 and consequently for ascertaining its degree of salubrity4 ,this addition of oxygen converts the nitrous gas into a powerful acid1 which has a strong affinity with water1 and which is itself susceptible of various additional degrees of oxygenation4 ,when the proportions of oxygen and azote is below three parts1 by weight1 of the former1 to one of the latter1 the acid is red coloured1 and emits copious fumes4 ,in this state1 by the application of a gentle heat1 it gives out nitrous gas2 and we term it1 in this degree of oxygenation1 nitrous acid4 ,when four parts1 by weight1 of oxygen1 are combined with one part of azote1 the acid is clear and colourless1 more fixed in the fire than the nitrous acid1 has less odour1 and its constituent elements are more firmly united4 ,this species of acid1 in conformity with our principles of nomenclature1 is called nitric acid4 ,thus1 nitric acid is the acid of nitre1 surcharged with oxygen2 nitrous acid is the acid of nitre surcharged with azote2 or1 what is the same thing1 with nitrous gas2 and this latter is azote not sufficiently saturated with oxygen to possess the properties of an acid4 ,to this degree of oxygenation1 we have afterwards1 in the course of this work1 given the generical name of oxyd#ad4 ,,footnotes3 #ab ,the term formerly used by the ,english chemists for this acid was written sulphureous2 but we have thought proper to spell it as above1 that it may better conform with the similar terminations of nitrous1 carbonous1 c4 to be used hereafter4 ,in general1 we have used the ,english terminations ic and ous to translate the terms of the ,author which end with ique and cux1 with hardly any other alterations4--,e4 #ac ,for this purpose1 the operation called decrepitation is used1 which consists in subjecting it to nearly a red heat1 in a proper vessel1 so as to evaporate all its water of crystallization4--,e4 #ad ,in strict conformity with the principles of the new nomenclature1 but which the ,author has given his reasons for deviating from in this instance1 the following ought to have been the terms for azote1 in its several degrees of oxygenation3 ,azote1 azotic gas1 7azote combined with caloric71 azotic oxyd gas1 nitrous acid1 and nitric acid4--,e4 ,,chap4 ,,vii4 ,of the ,decomposition of ,oxygen ,gas by means of ,metals1 and the ,formation of ,metallic ,oxyds4 ,oxygen has a stronger affinity with metals heated to a certain degree than with caloric2 in consequence of which1 all metallic bodies1 excepting gold1 silver1 and platina1 have the property of decomposing oxygen gas1 by attracting its base from the caloric with which it was combined4 ,we have already shown in what manner this decomposition takes place1 by means of mercury and iron2 having observed1 that1 in the case of the first1 it must be considered as a kind of gradual combustion1 whilst1 in the latter1 the combustion is extremely rapid1 and attended with a brilliant flame4 ,the use of the heat employed in these operations is to separate the particles of the metal from each other1 and to diminish their attraction of cohesion or aggregation1 or1 what is the same thing1 their mutual attraction for each other4 ,the absolute weight of metallic substances is augmented in proportion to the quantity of oxygen they absorb2 they1 at the same time1 lose their metallic splendour1 and are reduced into an earthy pulverulent matter4 ,in this state metals must not be considered as entirely saturated with oxygen1 because their action upon this element is counterbalanced by the power of affinity between it and caloric4 ,during the calcination of metals1 the oxygen is therefore acted upon by two separate and opposite powers1 that of its attraction for caloric1 and that exerted by the metal1 and only tends to unite with the latter in consequence of the excess of the latter over the former1 which is1 in general1 very inconsiderable4 ,wherefore1 when metallic substances are oxygenated in atmospheric air1 or in oxygen gas1 they are not converted into acids like sulphur1 phosphorus1 and charcoal1 but are only changed into intermediate substances1 which1 though approaching to the nature of salts1 have not acquired all the saline properties4 ,the old chemists have affixed the name of calx not only to metals in this state1 but to every body which has been long exposed to the action of fire without being melted4 ,they have converted this word calx into a generical term1 under which they confound calcareous earth1 which1 from a neutral salt1 which it really was before calcination1 has been changed by fire into an earthy alkali1 by losing half of its weight1 with metals which1 by the same means1 have joined themselves to a new substance1 whose quantity often exceeds half their weight1 and by which they have been changed almost into the nature of acids4 ,this mode of classifying substances of so very opposite natures1 under the same generic name1 would have been quite contrary to our principles of nomenclature1 especially as1 by retaining the above term for this state of metallic substances1 we must have conveyed very false ideas of its nature4 ,we have1 therefore1 laid aside the expression metallic calx altogether1 and have substituted in its place the term oxyd1 from the ,greek word ,greek3 oxys4 ,by this may be seen1 that the language we have adopted is both copious and expressive4 ,the first or lowest degree of oxygenation in bodies1 converts them into oxyds2 a second degree of additional oxygenation constitutes the class of acids1 of which the specific names1 drawn from their particular bases1 terminate in ous1 as the nitrous and sulphurous acids2 the third degree of oxygenation changes these into the species of acids distinguished by the termination in ic1 as the nitric and sulphuric acids2 and1 lastly1 we can express a fourth1 or highest degree of oxygenation1 by adding the word oxygenated to the name of the acid1 as has been already done with the oxygenated muriatic acid4 ,we have not confined the term oxyd to expressing the combinations of metals with oxygen1 but have extended it to signify that first degree of oxygenation in all bodies1 which1 without converting them into acids1 causes them to approach to the nature of salts4 ,thus1 we give the name of oxyd of sulphur to that soft substance into which sulphur is converted by incipient combustion2 and we call the yellow matter left by phosphorus1 after combustion1 by the name of oxyd of phosphorus4 ,in the same manner1 nitrous gas1 which is azote in its first degree of oxygenation1 is the oxyd of azote4 ,we have likewise oxyds in great numbers from the vegetable and animal kingdoms2 and ,i shall show1 in the sequel1 that this new language throws great light upon all the operations of art and nature4 ,we have already observed1 that almost all the metallic oxyds have peculiar and permanent colours4 ,these vary not only in the different species of metals1 but even according to the various degrees of oxygenation in the same metal4 ,hence we are under the necessity of adding two epithets to each oxyd1 one of which indicates the metal oxydated#ae1 while the other indicates the peculiar colour of the oxyd4 ,thus1 we have the black oxyd of iron1 the red oxyd of iron1 and the yellow oxyd of iron2 which expressions respectively answer to the old unmeaning terms of martial ethiops1 colcothar1 and rust of iron1 or ochre4 ,we have likewise the gray1 yellow1 and red oxyds of lead1 which answer to the equally false or insignificant terms1 ashes of lead1 massicot1 and minium4 ,these denominations sometimes become rather long1 especially when we mean to indicate whether the metal has been oxydated in the air1 by detonation with nitre1 or by means of acids2 but then they always convey just and accurate ideas of the corresponding object which we wish to express by their use4 ,all this will be rendered perfectly clear and distinct by means of the tables which are added to this work4 ,,footnotes3 #ae ,here we see the word oxyd converted into the verb to oxydate1 oxydated1 oxydating1 after the same manner with the derivation of the verb to oxygenate1 oxygenated1 oxygenating1 from the word oxygen4 ,i am not clear of the absolute necessity of this second verb here first introduced1 but think1 in a work of this nature1 that it is the duty of the translator to neglect every other consideration for the sake of strict fidelity to the ideas of his author4--,e4 ,,chap4 ,,viii4 ,of the ,radical ,principle of ,water1 and of its ,decomposition by ,charcoal and ,iron4 ,until very lately1 water has always been thought a simple substance1 insomuch that the older chemists considered it as an element4 ,such it undoubtedly was to them1 as they were unable to decompose it2 or1 at least1 since the decomposition which took place daily before their eyes was entirely unnoticed4 ,but we mean to prove1 that water is by no means a simple or elementary substance4 ,i shall not here pretend to give the history of this recent1 and hitherto contested discovery1 which is detailed in the ,memoirs of the ,academy for #agha1 but shall only bring forwards the principal proofs of the decomposition and composition of water2 and1 ,i may venture to say1 that these will be convincing to such as consider them impartially4 ,experiment ,first4 ,having fixed the glass tube ,,ef1 7,pl4 vii4 fig4 #aa47 of from #h to #ab lines diameter1 across a furnace1 with a small inclination from ,e to ,f1 lute the superior extremity ,e to the glass retort ,a1 containing a determinate quantity of distilled water1 and to the inferior extremity ,f1 the worm ,,ss fixed into the neck of the doubly tubulated bottle ,h1 which has the bent tube ,,kk adapted to one of its openings1 in such a manner as to convey such ariform fluids or gasses as may be disengaged1 during the experiment1 into a proper apparatus for determining their quantity and nature4 ,to render the success of this experiment certain1 it is necessary that the tube ,,ef be made of well annealed and difficultly fusible glass1 and that it be coated with a lute composed of clay mixed with powdered stone-ware2 besides which1 it must be supported about its middle by means of an iron bar passed through the furnace1 lest it should soften and bend during the experiment4 ,a tube of ,china-ware1 or porcellain1 would answer better than one of glass for this experiment1 were it not difficult to procure one so entirely free from pores as to prevent the passage of air or of vapours4 ,when things are thus arranged1 a fire is lighted in the furnace ,,efcd1 which is supported of such a strength as to keep the tube ,,ef red hot1 but not to make it melt2 and1 at the same time1 such a fire is kept up in the furnace ,,vvxx1 as to keep the water in the retort ,a continually boiling4 ,in proportion as the water in the retort ,a is evaporated1 it fills the tube ,,ef1 and drives out the air it contained by the tube ,,kk2 the aqueous gas formed by evaporation is condensed by cooling in the worm ,,ss1 and falls1 drop by drop1 into the tubulated bottle ,h4 ,having continued this operation until all the water be evaporated from the retort1 and having carefully emptied all the vessels employed1 we find that a quantity of water has passed over into the bottle ,h1 exactly equal to what was before contained in the retort ,a1 without any disengagement of gas whatsoever3 ,so that this experiment turns out to be a simple distillation2 and the result would have been exactly the same1 if the water had been run from one vessel into the other1 through the tube ,,ef1 without having undergone the intermediate incandescence4 ,experiment ,second4 ,the apparatus being disposed1 as in the former experiment1 #bh grs4 of charcoal1 broken into moderately small parts1 and which has previously been exposed for a long time to a red heat in close vessels1 are introduced into the tube ,,ef4 ,every thing else is managed as in the preceding experiment4 ,the water contained in the retort ,a is distilled1 as in the former experiment1 and1 being condensed in the worm1 falls into the bottle ,h2 but1 at the same time1 a considerable quantity of gas is disengaged1 which1 escaping by the tube ,,kk1 is received in a convenient apparatus for that purpose4 ,after the operation is finished1 we find nothing but a few atoms of ashes remaining in the tube ,,ef2 the #bh grs4 of charcoal having entirely disappeared4 ,when the disengaged gasses are carefully examined1 they are sound to weigh #aac4g grs4#af2 these are of two kinds1 viz4 #add cubical inches of carbonic acid gas1 weighing #ajj grs4 and #chj cubical inches of a very light gas1 weighing only #ac4g grs4 which takes fire when in contact with air1 by the approach of a lighted body2 and1 when the water which has passed over into the bottle ,h is carefully examined1 it is found to have lost #he4g grs4 of its weight4 ,thus1 in this experiment1 #he4g grs4 of water1 joined to #bh grs4 of charcoal1 have combined in such a way as to form #ajj grs4 of carbonic acid1 and #ac4g grs4 of a particular gas capable of being burnt4 ,i have already shown1 that #ajj grs4 of carbonic acid gas consists of #gb grs4 of oxygen1 combined with #bh grs4 of charcoal2 hence the #bh grs4 of charcoal placed in the glass tube have acquired #gb grs4 of oxygen from the water2 and it follows1 that #he4g grs4 of water are composed of #gb grs4 of oxygen1 combined with #ac4g grs4 of a gas susceptible of combustion4 ,we shall see presently that this gas cannot possibly have been disengaged from the charcoal1 and must1 consequently1 have been produced from the water4 ,i have suppressed some circumstances in the above account of this experiment1 which would only have complicated and obscured its results in the minds of the reader4 ,for instance1 the inflammable gas dissolves a very small part of the charcoal1 by which means its weight is somewhat augmented1 and that of the carbonic gas proportionally diminished4 ,altho' the alteration produced by this circumstance is very inconsiderable2 yet ,i have thought it necessary to determine its effects by rigid calculation1 and to report1 as above1 the results of the experiment in its simplified state1 as if this circumstance had not happened4 ,at any rate1 should any doubts remain respecting the consequences ,i have drawn from this experiment1 they will be fully dissipated by the following experiments1 which ,i am going to adduce in support of my opinion4 ,experiment ,third4 ,the apparatus being disposed exactly as in the former experiment1 with this difference1 that instead of the #bh grs4 of charcoal1 the tube ,,ef is filled with #bgd grs4 of soft iron in thin plates1 rolled up spirally4 ,the tube is made red hot by means of its furnace1 and the water in the retort ,a is kept constantly boiling till it be all evaporated1 and has passed through the tube ,,ef1 so as to be condensed in the bottle ,h4 ,no carbonic acid gas is disengaged in this experiment1 instead of which we obtain #daf cubical inches1 or #ae grs4 of inflammable gas1 thirteen times lighter than atmospheric air4 ,by examining the water which has been distilled1 it is found to have lost #ajj grs4 and the #bgd grs4 of iron confined in the tube are found to have acquired #he grs4 additional weight1 and its magnitude is considerably augmented4 ,the iron is now hardly at all attractable by the magnet2 it dissolves in acids without effervescence2 and1 in short1 it is converted into a black oxyd1 precisely similar to that which has been burnt in oxygen gas4 ,in this experiment we have a true oxydation of iron1 by means of water1 exactly similar to that produced in air by the assistance of heat4 ,one hundred grains of water having been decomposed1 #he grs4 of oxygen have combined with the iron1 so as to convert it into the state of black oxyd1 and #ae grs4 of a peculiar inflammable gas are disengaged3 ,from all this it clearly follows1 that water is composed of oxygen combined with the base of an inflammable gas1 in the respective proportions of #he parts1 by weight of the former1 to #ae parts of the latter4 ,thus water1 besides the oxygen1 which is one of its elements in common with many other substances1 contains another element as its constituent base or radical1 and for which we must find an appropriate term4 ,none that we could think of seemed better adapted than the word hydrogen1 which signifies the generative principle of water1 from ,greek3 ydor aqua1 and ,greek3 geinomas gignor#ag4 ,we call the combination of this element with caloric hydrogen gas2 and the term hydrogen expresses the base of that gas1 or the radical of water4 ,this experiment furnishes us with a new combustible body1 or1 in other words1 a body which has so much affinity with oxygen as to draw it from its connection with caloric1 and to decompose air or oxygen gas4 ,this combustible body has itself so great affinity with caloric1 that1 unless when engaged in a combination with some other body1 it always subsists in the ariform or gasseous state1 in the usual temperature and pressure of our atmosphere4 ,in this state of gas it is about #a_/ac of the weight of an equal bulk of atmospheric air2 it is not absorbed by water1 though it is capable of holding a small quantity of that fluid in solution1 and it is incapable of being used for respiration4 ,as the property this gas possesses1 in common with all other combustible bodies1 is nothing more than the power of decomposing air1 and carrying off its oxygen from the caloric with which it was combined1 it is easily understood that it cannot burn1 unless in contact with air or oxygen gas4 ,hence1 when we set fire to a bottle full of this gas1 it burns gently1 first at the neck of the bottle1 and then in the inside of it1 in proportion as the external air gets in3 ,this combustion is slow and successive1 and only takes place at the surface of contact between the two gasses4 ,it is quite different when the two gasses are mixed before they are set on fire3 ,if1 for instance1 after having introduced one part of oxygen gas into a narrow mouthed bottle1 we fill it up with two parts of hydrogen gas1 and bring a lighted taper1 or other burning body1 to the mouth of the bottle1 the combustion of the two gasses takes place instantaneously with a violent explosion4 ,this experiment ought only to be made in a bottle of very strong green glass1 holding not more than a pint1 and wrapped round with twine1 otherwise the operator will be exposed to great danger from the rupture of the bottle1 of which the fragments will be thrown about with great force4 ,if all that has been related above1 concerning the decomposition of water1 be exactly conformable to truth2--if1 as ,i have endeavoured to prove1 that substance be really composed of hydrogen1 as its proper constituent element1 combined with oxygen1 it ought to follow1 that1 by reuniting these two elements together1 we should recompose water2 and that this actually happens may be judged of by the following experiment4 ,experiment ,fourth4 ,i took a large cristal baloon1 ,a1 ,pl4 iv4 fig4 #e4 holding about #cj pints1 having a large opening1 to which was cemented the plate of copper ,,bc1 pierced with four holes1 in which four tubes terminate4 ,the first tube1 ,h h1 is intended to be adapted to an air pump1 by which the baloon is to be exhausted of its air4 ,the second tube gg1 communicates1 by its extremity ,,mm1 with a reservoir of oxygen gas1 with which the baloon is to be filled4 ,the third tube d ,d d'1 communicates1 by its extremity d ,,nn1 with a reservoir of hydrogen gas4 ,the extremity d' of this tube terminates in a capillary opening1 through which the hydrogen gas contained in the reservoir is forced1 with a moderate degree of quickness1 by the pressure of one or two inches of water4 ,the fourth tube contains a metallic wire ,,gl1 having a knob at its extremity ,l1 intended for giving an electrical spark from ,l to d'1 on purpose to set fire to the hydrogen gas3 ,this wire is moveable in the tube1 that we may be able to separate the knob ,l from the extremity d' of the tube ,d d'4 ,the three tubes d ,d d'1 gg1 and ,h h1 are all provided with stop-cocks4 ,that the hydrogen gas and oxygen gas may be as much as possible deprived of water1 they are made to pass1 in their way to the baloon ,a1 through the tubes ,,mm1 ,,nn1 of about an inch diameter1 and filled with salts1 which1 from their deliquescent nature1 greedily attract the moisture of the air3 ,such are the acetite of potash1 and the muriat or nitrat of lime#ah4 ,these salts must only be reduced to a coarse powder1 lest they run into lumps1 and prevent the gasses from geting through their interstices4 ,we must be provided before hand with a sufficient quantity of oxygen gas1 carefully purified from all admixture of carbonic acid1 by long contact with a solution of potash#ai4 ,we must likewise have a double quantity of hydrogen gas1 carefully purified in the same manner by long contact with a solution of potash in water4 ,the best way of obtaining this gas free from mixture is1 by decomposing water with very pure soft iron1 as directed in ,exp4 #c4 of this chapter4 ,having adjusted every thing properly1 as above directed1 the tube ,h h is adapted to an air-pump1 and the baloon ,a is exhausted of its air4 ,we next admit the oxygen gas so as to fill the baloon1 and then1 by means of pressure1 as is before mentioned1 force a small stream of hydrogen gas through its tube ,d d'1 which we immediately set on fire by an electric spark4 ,by means of the above described apparatus1 we can continue the mutual combustion of these two gasses for a long time1 as we have the power of supplying them to the baloon from their reservoirs1 in proportion as they are consumed4 ,i have in another place#bj given a description of the apparatus used in this experiment1 and have explained the manner of ascertaining the quantities of the gasses consumed with the most scrupulous exactitude4 ,in proportion to the advancement of the combustion1 there is a deposition of water upon the inner surface of the baloon or matrass ,a3 ,the water gradually increases in quantity1 and1 gathering into large drops1 runs down to the bottom of the vessel4 ,it is easy to ascertain the quantity of water collected1 by weighing the baloon both before and after the experiment4 ,thus we have a twofold verification of our experiment1 by ascertaining both the quantities of the gasses employed1 and of the water formed by their combustion3 ,these two quantities must be equal to each other4 ,by an operation of this kind1 ,mr ,meusnier and ,i ascertained that it required #he parts1 by weight1 of oxygen1 united to #ae parts of hydrogen1 to compose #ajj parts of water4 ,this experiment1 which has not hitherto been published1 was made in presence of a numerous committee from the ,royal ,academy4 ,we exerted the most scrupulous attention to its accuracy2 and have reason to believe that the above propositions cannot vary a two hundredth part from absolute truth4 ,from these experiments1 both analytical and synthetic1 we may now affirm that we have ascertained1 with as much certainty as is possible in physical or chemical subjects1 that water is not a simple elementary substance1 but is composed of two elements1 oxygen and hydrogen2 which elements1 when existing separately1 have so strong affinity for caloric1 as only to subsist under the form of gas in the common temperature and pressure of our atmosphere4 ,this decomposition and recomposition of water is perpetually operating before our eyes1 in the temperature of the atmosphere1 by means of compound elective attraction4 ,we shall presently see that the phenomena attendant upon vinous fermentation1 putrefaction1 and even vegetation1 are produced1 at least in a certain degree1 by decomposition of water4 ,it is very extraordinary that this fact should have hitherto been overlooked by natural philosophers and chemists3 ,indeed1 it strongly proves1 that1 in chemistry1 as in moral philosophy1 it is extremely difficult to overcome prejudices imbibed in early education1 and to search for truth in any other road than the one we have been accustomed to follow4 ,i shall finish this chapter by an experiment much less demonstrative than those already related1 but which has appeared to make more impression than any other upon the minds of many people4 ,when #af ounces of alkohol are burnt in an apparatus#ba properly adapted for collecting all the water disengaged during the combustion1 we obtain from #ag to #ah ounces of water4 ,as no substance can furnish a product larger than its original bulk1 it follows1 that something else has united with the alkohol during its combustion2 and ,i have already shown that this must be oxygen1 or the base of air4 ,thus alkohol contains hydrogen1 which is one of the elements of water2 and the atmospheric air contains oxygen1 which is the other element necessary to the composition of water4 ,this experiment is a new proof that water is a compound substance4 ,,footnotes3 #af ,in the latter part of this work will be found a particular account of the processes necessary for separating the different kinds of gasses1 and for determining their quantities4--,a4 #ag ,this expression ,hydrogen has been very severely criticised by some1 who pretend that it signifies engendered by water1 and not that which engenders water4 ,the experiments related in this chapter prove1 that1 when water is decomposed1 hydrogen is produced1 and that1 when hydrogen is combined with oxygen1 water is produced3 ,so that we may say1 with equal truth1 that water is produced from hydrogen1 or hydrogen is produced from water4--,a4 #ah ,see the nature of these salts in the second part of this book4--,a4 #ai ,by potash is here meant1 pure or caustic alkali1 deprived of carbonic acid by means of quick-lime3 ,in general1 we may observe here1 that all the alkalies and earths must invariably be considered as in their pure or caustic state1 unless otherwise expressed4--,e4 ,the method of obtaining this pure alkali of potash will be given in the sequel4--,a4 #bj ,see the third part of this work4--,a4 #ba ,see an account of this apparatus in the third part of this work4--,a4 ,,chap4 ,,ix4 ,of the quantities of ,caloric disengaged from different species of ,combustion4 ,we have already mentioned1 that1 when any body is burnt in the center of a hollow sphere of ice and supplied with air at the temperature of zero 7#cb71 the quantity of ice melted from the inside of the sphere becomes a measure of the relative quantities of caloric disengaged4 ,mr de la ,place and ,i gave a description of the apparatus employed for this kind of experiment in the ,memoirs of the ,academy for #aghj1 p4 #cee2 and a description and plate of the same apparatus will be found in the third part of this work4 ,with this apparatus1 phosphorus1 charcoal1 and hydrogen gas1 gave the following results3 ,one pound of phosphorus melted #ajj libs4 of ice4 ,one pound of charcoal melted #if libs4 #h oz4 ,one pound of hydrogen gas melted #bie libs4 #i oz4 #c-a_/b gros4 ,as a concrete acid is formed by the combustion of phosphorus1 it is probable that very little caloric remains in the acid1 and1 consequently1 that the above experiment gives us very nearly the whole quantity of caloric contained in the oxygen gas4 ,even if we suppose the phosphoric acid to contain a good deal of caloric1 yet1 as the phosphorus must have contained nearly an equal quantity before combustion1 the error must be very small1 as it will only consist of the difference between what was contained in the phosphorus before1 and in the phosphoric acid after combustion4 ,i have already shown in ,chap4 ,v4 that one pound of phosphorus absorbs one pound eight ounces of oxygen during combustion2 and since1 by the same operation1 #ajj lib4 of ice are melted1 it follows1 that the quantity of caloric contained in one pound of oxygen gas is capable of melting #ff libs4 #aj oz4 #e gros #bd grs4 of ice4 ,one pound of charcoal during combustion melts only #if libs4 #h oz4 of ice1 whilst it absorbs #b libs4 #i oz4 #a gros #aj grs4 of oxygen4 ,by the experiment with phosphorus1 this quantity of oxygen gas ought to disengage a quantity of caloric sufficient to melt #aga libs4 #f oz4 #e gros of ice2 consequently1 during this experiment1 a quantity of caloric1 sufficient to melt #gd libs4 #ad oz4 #e gros of ice disappears4 ,carbonic acid is not1 like phosphoric acid1 in a concrete state after combustion but in the state of gas1 and requires to be united with caloric to enable it to subsist in that state2 the quantity of caloric missing in the last experiment is evidently employed for that purpose4 ,when we divide that quantity by the weight of carbonic acid1 formed by the combustion of one pound of charcoal1 we find that the quantity of caloric necessary for changing one pound of carbonic acid from the concrete to the gasseous state1 would be capable of melting #bj libs4 #ae oz4 #e gros of ice4 ,we may make a similar calculation with the combustion of hydrogen gas and the consequent formation of water4 ,during the combustion of one pound of hydrogen gas1 #e libs4 #aj oz4 #e gros #bd grs4 of oxygen gas are absorbed1 and #bie libs4 #i oz4 #c-a_/b gros of ice are melted4 ,but #e libs4 #aj oz4 #e gros #bd grs4 of oxygen gas1 in changing from the ariform to the solid state1 loses1 according to the experiment with phosphorus1 enough of caloric to have melted #cgg libs4 #ab oz4 #c gros of ice4 ,there is only disengaged1 from the same quantity of oxygen1 during its combustion with hydrogen gas1 as much caloric as melts #bie libs4 #b oz4 #c-a_/b gros2 wherefore there remains in the water at ,zero 7#cb71 formed1 during this experiment1 as much caloric as would melt #hb libs4 #i oz4 #g-a_/b gros of ice4 ,hence1 as #f libs4 #aj oz4 #e gros #bd grs4 of water are formed from the combustion of one pound of hydrogen gas with #e libs4 #aj oz4 #e gros #bd grs4 of oxygen1 it follows that1 in each pound of water1 at the temperature of ,zero1 7#cb71 there exists as much caloric as would melt #ab libs4 #e oz4 #b gros #dh grs4 of ice1 without taking into account the quantity originally contained in the hydrogen gas1 which we have been obliged to omit1 for want of data to calculate its quantity4 ,from this it appears that water1 even in the state of ice1 contains a considerable quantity of caloric1 and that oxygen1 in entering into that combination1 retains likewise a good proportion4 ,from these experiments1 we may assume the following results as sufficiently established4 ,combustion of ,phosphorus4 ,from the combustion of phosphorus1 as related in the foregoing experiments1 it appears1 that one pound of phosphorus requires #a lib4 #h oz4 of oxygen gas for its combustion1 and that #b libs4 #h oz4 of concrete phosphoric acid are produced4 ,the quantity of caloric disengaged by the combustion of one pound of phosphorus1 expressed by the number of pounds of ice melted during that operation1 is #ajj4jjjjj4 ,the quantity disengaged from each pound of oxygen1 during the combustion of phosphorus1 expressed in the same manner1 is #ff4ffffg4 ,the quantity disengaged during the formation of one pound of phosphoric acid1 #dj4jjjjj4 ,the quantity remaining in each pound of phosphoric acid1 #j4jjjjj7;,a74 ,note ,a3 ,we here suppose the phosphoric acid not to contain any caloric1 which is not strictly true2 but1 as ,i have before observed1 the quantity it really contains is probably very small1 and we have not given it a value1 for want of a sufficient data to go upon4--,a4 ,combustion of ,charcoal4 ,in the combustion of one pound of charcoal1 #b libs4 #i oz4 #a gros #aj grs4 of oxygen gas are absorbed1 and #c libs4 #i oz4 #a gros #aj grs4 of carbonic acid gas are formed4 ,caloric1 disengaged daring the combustion of one pound of charcoal1 #if4ejjjj7;,a74 ,caloric disengaged during the combustion of charcoal1 from each pound of oxygen gas absorbed1 #cg4ebhbc4 ,caloric disengaged during the formation of one pound of carbonic acid gas1 #bg4jbjbd4 ,caloric retained by each pound of oxygen after the combustion1 #bi4achdd4 ,caloric necessary for supporting one pound of carbonic acid in the state of gas1 #bj4igifj4 ,note ,a3 ,all these relative quantities of caloric are expressed by the number of pounds of ice1 and decimal parts1 melted during the several operations4--,e4 ,combustion of ,hydrogen ,gas4 ,in the combustion of one pound of hydrogen gas1 #e libs4 #aj oz4 #e gros #bd grs4 of oxygen gas are absorbed1 and #f libs4 #aj oz4 #e gros #bd grs4 of water are formed4 ,caloric from each lib4 of hydrogen gas1 #bie4ehiej4 ,caloric from each lib4 of oxygen gas1 #eb4afbhj4 ,caloric disengaged during the formation of each pound of water1 #dd4cchdj4 ,caloric retained by each lib4 of oxygen after combustion with hydrogen1 #ad4ejchf4 ,caloric retained by each lib4 of water at the temperature of ,zero 7#cb71 #ab4cbhbc4 ,of the ,formation of ,nitric ,acid4 ,when we combine nitrous gas with oxygen gas1 so as to form nitric or nitrous acid a degree of heat is produced1 which is much less considerable than what is evolved during the other combinations of oxygen2 whence it follows that oxygen1 when it becomes fixed in nitric acid1 retains a great part of the heat which it possessed in the state of gas4 ,it is certainly possible to determine the quantity of caloric which is disengaged during the combination of these two gasses1 and consequently to determine what quantity remains after the combination takes place4 ,the first of these quantities might be ascertained1 by making the combination of the two gasses in an apparatus surrounded by ice2 but1 as the quantity of caloric disengaged is very inconsiderable1 it would be necessary to operate upon a large quantity of the two gasses in a very troublesome and complicated apparatus4 ,by this consideration1 ,mr de la ,place and ,i have hitherto been prevented from making the attempt4 ,in the mean time1 the place of such an experiment may be supplied by calculations1 the results of which cannot be very far from truth4 ,mr de la ,place and ,i deflagrated a convenient quantity of nitre and charcoal in an ice apparatus1 and found that twelve pounds of ice were melted by the deflagration of one pound of nitre4 ,we shall see1 in the sequel1 that one pound of nitre is composed1 as under1 of ,potash #g oz4 #f gros #ea4hd grs4 #deae4hd grs4 ,dry acid #h #a #ba4af #dgjj4af4 ,the above quantity of dry acid is composed of ,oxygen #f oz4 #c gros #ff4cd grs4 #cgch4cd grs4 ,azote #a #e #be4hb #ifa4hb4 ,by this we find that1 during the above deflagration1 #b gros #a-a_/c gr4 of charcoal have suffered combustion1 alongst with #cgch4cd grs4 or #f oz4 #c gros #ff4cd grs4 of oxygen4 ,hence1 since #ab libs4 of ice were melted during the combustion1 it follows1 that one pound of oxygen burnt in the same manner would have melted #bi4ehcbj libs4 of ice4 ,to which the quantity of caloric1 retained by a pound of oxygen after combining with charcoal to form carbonic acid gas1 being added1 which was already ascertained to be capable of melting #bi4achdd libs4 of ice1 we have for the total quantity of caloric remaining in a pound of oxygen1 when combined with nitrous gas in the nitric acid #eh4gbafd2 which is the number of pounds of ice the caloric remaining in the oxygen in that state is capable of melting4 ,we have before seen that1 in the state of oxygen gas1 it contained at least #ff4ffffg2 wherefore it follows that1 in combining with azote to form nitric acid1 it only loses #g4idejb4 ,farther experiments upon this subject are necessary to ascertain how far the results of this calculation may agree with direct fact4 ,this enormous quantity of caloric retained by oxygen in its combination into nitric acid1 explains the cause of the great disengagement of caloric during the deflagrations of nitre2 or1 more strictly speaking1 upon all occasions of the decomposition of nitric acid4 ,of the ,combustion of ,wax4 ,having examined several cases of simple combustion1 ,i mean now to give a few examples of a more complex nature4 ,one pound of wax-taper being allowed to burn slowly in an ice apparatus1 melted #acc libs4 #b oz4 #e-a_/c gros of ice4 ,according to my experiments in the ,memoirs of the ,academy for #aghd1 p4 #fjf1 one pound of wax-taper consists of #ac oz4 #a gros #bc grs4 of charcoal1 and #b oz4 #f gros #di grs4 of hydrogen4 ,by the foregoing experiments1 the above quantity of charcoal ought to melt #gi4cicij libs4 of ice2 and the hydrogen should melt #eb4cgfje --------- ,in all #aca4gfiie libs4 ,thus1 we see the quantity of caloric disengaged from a burning taper1 is pretty exactly conformable to what was obtained by burning separately a quantity of charcoal and hydrogen equal to what enters into its composition4 ,these experiments with the taper were several times repeated1 so that ,i have reason to believe them accurate4 ,combustion of ,olive ,oil4 ,we included a burning lamp1 containing a determinate quantity of olive-oil1 in the ordinary apparatus1 and1 when the experiment was finished1 we ascertained exactly the quantities of oil consumed1 and of ice melted2 the result was1 that1 during the combustion of one pound of olive-oil1 #adh libs4 #ad oz4 #a gros of ice were melted4 ,by my experiments in the ,memoirs of the ,academy for #aghd1 and of which the following ,chapter contains an abstract1 it appears that one pound of olive-oil consists of #ab oz4 #e gros #e grs4 of charcoal1 and #c oz4 #b gros #fg grs4 of hydrogen4 ,by the foregoing experiments1 that quantity of charcoal should melt #gf4ahgbc libs4 of ice1 and the quantity of hydrogen in a pound of the oil should melt #fb4aejec libs4 ,the sum of these two gives #ach4ccggf libs4 of ice1 which the two constituent elements of the oil would have melted1 had they separately suffered combustion1 whereas the oil really melted #adh4hhccj libs4 which gives an excess of #aj4edeed in the result of the experiment above the calculated result1 from data furnished by former experiments4 ,this difference1 which is by no means very considerable1 may arise from errors which are unavoidable in experiments of this nature1 or it may be owing to the composition of oil not being as yet exactly ascertained4 ,it proves1 however1 that there is a great agreement between the results of our experiments1 respecting the combination of caloric1 and those which regard its disengagement4 ,the following desiderata still remain to be determined1 viz4 ,what quantity of caloric is retained by oxygen1 after combining with metals1 so as to convert them into oxyds2 ,what quantity is contained by hydrogen1 in its different states of existence2 and to ascertain1 with more precision than is hitherto attained1 how much caloric is disengaged during the formation of water1 as there still remain considerable doubts with respect to our present determination of this point1 which can only be removed by farther experiments4 ,we are at present occupied with this inquiry2 and1 when once these several points are well ascertained1 which we hope they will soon be1 we shall probably be under the necessity of making considerable corrections upon most of the results of the experiments and calculations in this ,chapter4 ,i did not1 however1 consider this as a sufficient reason for withholding so much as is already known from such as may be inclined to labour upon the same subject4 ,it is difficult1 in our endeavours to discover the principles of a new science1 to avoid beginning by guess-work2 and it is rarely possible to arrive at perfection from the first setting out4 ,,chap4 ,x4 ,of the ,combination of ,combustible ,substances with each other4 ,as combustible substances in general have a great affinity for oxygen1 they ought likewise to attract1 or tend to combine with each other2 quae sunt eadem uni tertio1 sunt eadem inter se2 and the axiom is found to be true4 ,almost all the metals1 for instance1 are capable of uniting with each other1 and forming what are called alloys#bb1 in common language4 ,most of these1 like all combinations1 are susceptible of several degrees of saturation2 the greater number of these alloys are more brittle than the pure metals of which they are composed1 especially when the metals alloyed together are considerably different in their degrees of fusibility4 ,to this difference in fusibility1 part of the phenomena attendant upon alloyage are owing1 particularly the property of iron1 called by workmen hotshort4 ,this kind of iron must be considered as an alloy1 or mixture of pure iron1 which is almost infusible1 with a small portion of some other metal which fuses in a much lower degree of heat4 ,so long as this alloy remains cold1 and both metals are in the solid state1 the mixture is malleable2 but1 if heated to a sufficient degree to liquify the more fusible metal1 the particles of the liquid metal1 which are interposed between the particles of the metal remaining solid1 must destroy their continuity1 and occasion the alloy to become brittle4 ,the alloys of mercury1 with the other metals1 have usually been called amalgams1 and we see no inconvenience from continuing the use of that term4 ,sulphur1 phosphorus1 and charcoal1 readily unite with metals4 ,combinations of sulphur with metals are usually named pyrites4 ,their combinations with phosphorus and charcoal are either not yet named1 or have received new names only of late2 so that we have not scrupled to change them according to our principles4 ,the combinations of metal and sulphur we call sulphurets1 those with phosphorus phosphurets1 and those formed with charcoal carburets4 ,these denominations are extended to all the combinations into which the above three substances enter1 without being previously oxygenated4 ,thus1 the combination of sulphur with potash1 or fixed vegetable alkali1 is called sulphuret of potash2 that which it forms with ammoniac1 or volatile alkali1 is termed sulphuret of ammoniac4 ,hydrogen is likewise capable of combining with many combustible substances4 ,in the state of gas1 it dissolves charcoal1 sulphur1 phosphorus1 and several metals2 we distinguish these combinations by the terms1 carbonated hydrogen gas1 sulphurated hydrogen gas1 and phosphorated hydrogen gas4 ,the sulphurated hydrogen gas was called hepatic air by former chemists1 or foetid air from sulphur1 by ,mr ,scheele4 ,the virtues of several mineral waters1 and the foetid smell of animal excrements1 chiefly arise from the presence of this gas4 ,the phosphorated hydrogen gas is remarkable for the property1 discovered by ,mr ,gengembre1 of taking fire spontaneously upon getting into contact with atmospheric air1 or1 what is better1 with oxygen gas4 ,this gas has a strong flavour1 resembling that of putrid fish2 and it is very probable that the phosphorescent quality of fish1 in the state of putrefaction1 arises from the escape of this species of gas4 ,when hydrogen and charcoal are combined together1 without the intervention of caloric1 to bring the hydrogen into the state of gas1 they form oil1 which is either fixed or volatile1 according to the proportions of hydrogen and charcoal in its composition4 ,the chief difference between fixed or fat oils drawn from vegetables by expression1 and volatile or essential oils1 is1 that the former contains an excess of charcoal1 which is separated when the oils are heated above the degree of boiling water2 whereas the volatile oils1 containing a just proportion of these two constituent ingredients1 are not liable to be decomposed by that heat1 but1 uniting with caloric into the gasseous state1 pass over in distillation unchanged4 ,in the ,memoirs of the ,academy for #aghd1 p4 #eic4 ,i gave an account of my experiments upon the composition of oil and alkohol1 by the union of hydrogen with charcoal1 and of their combination with oxygen4 ,by these experiments1 it appears that fixed oils combine with oxygen during combustion1 and are thereby converted into water and carbonic acid4 ,by means of calculation applied to the products of these experiments1 we find that fixed oil is composed of #ba parts1 by weight1 of hydrogen combined with #gi parts of charcoal4 ,perhaps the solid substances of an oily nature1 such as wax1 contain a proportion of oxygen1 to which they owe their state of solidity4 ,i am at present engaged in a series of experiments1 which ,i hope will throw great light upon this subject4 ,it is worthy of being examined1 whether hydrogen in its concrete state1 uncombined with caloric1 be susceptible of combination with sulphur1 phosphorus1 and the metals4 ,there is nothing that we know of1 which1 a priori1 should render these combinations impossible2 for combustible bodies being in general susceptible of combination with each other1 there is no evident reason for hydrogen being an exception to the rule3 ,however1 no direct experiment as yet establishes either the possibility or impossibility of this union4 ,iron and zinc are the most likely1 of all the metals1 for entering into combination with hydrogen2 but1 as these have the property of decomposing water1 and as it is very difficult to get entirely free from moisture in chemical experiments1 it is hardly possible to determine whether the small portions of hydrogen gas1 obtained in certain experiments with these metals1 were previously combined with the metal in the state of solid hydrogen1 or if they were produced by the decomposition of a minute quantity of water4 ,the more care we take to prevent the presence of water in these experiments1 the less is the quantity of hydrogen gas procured2 and1 when very accurate precautions are employed1 even that quantity becomes hardly sensible4 ,however this inquiry may turn out respecting the power of combustible bodies1 as sulphur1 phosphorus1 and metals1 to absorb hydrogen1 we are certain that they only absorb a very small portion2 and that this combination1 instead of being essential to their constitution1 can only be considered as a foreign substance1 which contaminates their purity4 ,it is the province of the advocates#bc for this system to prove1 by decisive experiments1 the real existence of this combined hydrogen1 which they have hitherto only done by conjectures founded upon suppositions4 ,,footnotes3 #bb ,this term alloy1 which we have from the language of the arts1 serves exceedingly well for distinguishing all the combinations or intimate unions of metals with each other1 and is adopted in our new nomenclature for that purpose4--,a4 #bc ,by these are meant the supporters of the phlogistic theory1 who at present consider hydrogen1 or the base of inflammable air1 as the phlogiston of the celebrated ,stahl4--,e4 ,,chap4 ,,xi4 ,observations upon ,oxyds and ,acids with several ,bases--and upon the ,composition of ,animal and ,vegetable ,substances4 ,we have1 in ,chap4 ,v4 and ,,viii4 examined the products resulting from the combustion of the four simple combustible substances1 sulphur1 phosphorus1 charcoal1 and hydrogen3 ,we have shown1 in ,chap4 ,x that the simple combustible substances are capable of combining with each other into compound combustible substances1 and have observed that oils in general1 and particularly the fixed vegetable oils1 belong to this class1 being composed of hydrogen and charcoal4 ,it remains1 in this chapter1 to treat of the oxygenation of these compound combustible substances1 and to show that there exist acids and oxyds having double and triple bases4 ,nature furnishes us with numerous examples of this kind of combinations1 by means of which1 chiefly1 she is enabled to produce a vast variety of compounds from a very limited number of elements1 or simple substances4 ,it was long ago well known1 that1 when muriatic and nitric acids were mixed together1 a compound acid was formed1 having properties quite distinct from those of either of the acids taken separately4 ,this acid was called aqua regia1 from its most celebrated property of dissolving gold1 called king of metals by the alchymists4 ,mr ,berthollet has distinctly proved that the peculiar properties of this acid arise from the combined action of its two acidifiable bases2 and for this reason we have judged it necessary to distinguish it by an appropriate name3 ,that of nitro-muriatic acid appears extremely applicable1 from its expressing the nature of the two substances which enter into its composition4 ,this phenomenon of a double base in one acid1 which had formerly been observed only in the nitro-muriatic acid1 occurs continually in the vegetable kingdom1 in which a simple acid1 or one possessed of a single acidifiable base1 is very rarely found4 ,almost all the acids procurable from this kingdom have bases composed of charcoal and hydrogen1 or of charcoal1 hydrogen1 and phosphorus1 combined with more or less oxygen4 ,all these bases1 whether double or triple1 are likewise formed into oxyds1 having less oxygen than is necessary to give them the properties of acids4 ,the acids and oxyds from the animal kingdom are still more compound1 as their bases generally consist of a combination of charcoal1 phosphorus1 hydrogen1 and azote4 ,as it is but of late that ,i have acquired any clear and distinct notions of these substances1 ,i shall not1 in this place1 enlarge much upon the subject1 which ,i mean to treat of very fully in some memoirs ,i am preparing to lay before the ,academy4 ,most of my experiments are already performed2 but1 to be able to give exact reports of the resulting quantities1 it is necessary that they be carefully repeated1 and increased in number3 ,wherefore1 ,i shall only give a short enumeration of the vegetable and animal acids and oxyds1 and terminate this article by a few reflections upon the composition of vegetable and animal bodies4 ,sugar1 mucus1 under which term we include the different kinds of gums1 and starch1 are vegetable oxyds1 having hydrogen and charcoal combined1 in different proportions1 as their radicals or bases1 and united with oxygen1 so as to bring them to the state of oxyds4 ,from the state of oxyds they are capable of being changed into acids by the addition of a fresh quantity of oxygen2 and1 according to the degrees of oxygenation1 and the proportion of hydrogen and charcoal in their bases1 they form the several kinds of vegetable acids4 ,it would be easy to apply the principles of our nomenclature to give names to these vegetable acids and oxyds1 by using the names of the two substances which compose their bases3 ,they would thus become hydro-carbonous acids and oxyds3 ,in this method we might indicate which of their elements existed in excess1 without circumlocution1 after the manner used by ,mr ,rouelle for naming vegetable extracts3 ,he calls these extracto-resinous when the extractive matter prevails in their composition1 and resino-extractive when they contain a larger proportion of resinous matter4 ,upon that plan1 and by varying the terminations according to the formerly established rules of our nomenclature1 we have the following denominations3 ,hydro-carbonous1 hydro-carbonic2 carbono-hydrous1 and carbono-hydric oxyds4 ,and for the acids3 ,hydro-carbonous1 hydro carbonic1 oxygenated hydro-carbonic2 carbono-hydrous1 carbono-hydric1 and oxygenated carbono-hydric4 ,it is probable that the above terms would suffice for indicating all the varieties in nature1 and that1 in proportion as the vegetable acids become well understood1 they will naturally arrange themselves under these denominations4 ,but1 though we know the elements of which these are composed1 we are as yet ignorant of the proportions of these ingredients1 and are still far from being able to class them in the above methodical manner2 wherefore1 we have determined to retain the ancient names provisionally4 ,i am somewhat farther advanced in this inquiry than at the time of publishing our conjunct essay upon chemical nomenclature2 yet it would be improper to draw decided consequences from experiments not yet sufficiently precise3 ,though ,i acknowledge that this part of chemistry still remains in some degree obscure1 ,i must express my expectations of its being very soon elucidated4 ,i am still more forcibly necessitated to follow the same plan in naming the acids1 which have three or four elements combined in their bases2 of these we have a considerable number from the animal kingdom1 and some even from vegetable substances4 ,azote1 for instance1 joined to hydrogen and charcoal1 form the base or radical of the ,prussic acid2 we have reason to believe that the same happens with the base of the ,gallic acid2 and almost all the animal acids have their bases composed of azote1 phosphorus1 hydrogen1 and charcoal4 ,were we to endeavour to express at once all these four component parts of the bases1 our nomenclature would undoubtedly be methodical2 it would have the property of being clear and determinate2 but this assemblage of ,greek and ,latin substantives and adjectives1 which are not yet universally admitted by chemists1 would have the appearance of a barbarous language1 difficult both to pronounce and to be remembered4 ,besides1 this part of chemistry being still far from that accuracy it must arrive to1 the perfection of the science ought certainly to precede that of its language2 and we must still1 for some time1 retain the old names for the animal oxyds and acids4 ,we have only ventured to make a few slight modifications of these names1 by changing the termination into ous1 when we have reason to suppose the base to be in excess1 and into ic1 when we suspect the oxygen predominates4 ,the following are all the vegetable acids hitherto known3 #a4 ,acetous acid4 #b4 ,acetic acid4 #c4 ,oxalic acid4 #d4 ,tartarous acid4 #e4 ,pyro-tartarous acid4 #f4 ,citric acid4 #g4 ,malic acid4 #h4 ,pyro-mucous acid4 #i4 ,pyro-lignous acid4 #aj4 ,gallic acid4 #aa4 ,benzoic acid4 #ab4 ,camphoric acid4 #ac4 ,succinic acid4 ,though all these acids1 as has been already said1 are chiefly1 and almost entirely1 composed of hydrogen1 charcoal1 and oxygen1 yet1 properly speaking1 they contain neither water carbonic acid nor oil1 but only the elements necessary for forming these substances4 ,the power of affinity reciprocally exerted by the hydrogen1 charcoal1 and oxygen1 in these acids1 is in a state of equilibrium only capable of existing in the ordinary temperature of the atmosphere2 for1 when they are heated but a very little above the temperature of boiling water1 this equilibrium is destroyed1 part of the oxygen and hydrogen unite1 and form water2 part of the charcoal and hydrogen combine into oil2 part of the charcoal and oxygen unite to form carbonic acid2 and1 lastly1 there generally remains a small portion of charcoal1 which1 being in excess with respect to the other ingredients1 is left free4 ,i mean to explain this subject somewhat farther in the succeeding chapter4 ,the oxyds of the animal kingdom are hitherto less known than those from the vegetable kingdom1 and their number is as yet not at all determined4 ,the red part of the blood1 lymph1 and most of the secretions1 are true oxyds1 under which point of view it is very important to consider them4 ,we are only acquainted with six animal acids1 several of which1 it is probable1 approach very near each other in their nature1 or1 at least1 differ only in a scarcely sensible degree4 ,i do not include the phosphoric acid amongst these1 because it is found in all the kingdoms of nature4 ,they are1 #a4 ,lactic acid4 #b4 ,saccholactic acid4 #c4 ,bombic acid4 #d4 ,formic acid4 #e4 ,sebacic acid4 #f4 ,prussic acid4 ,the connection between the constituent elements of the animal oxyds and acids is not more permanent than in those from the vegetable kingdom1 as a small increase of temperature is sufficient to overturn it4 ,i hope to render this subject more distinct than has been done hitherto in the following chapter4 ,,chap4 ,,xii4 ,of the ,decomposition of ,vegetable and ,animal ,substances by the ,action of ,fire4 ,before we can thoroughly comprehend what takes place during the decomposition of vegetable substances by fire1 we must take into consideration the nature of the elements which enter into their composition1 and the different affinities which the particles of these elements exert upon each other1 and the affinity which caloric possesses with them4 ,the true constituent elements of vegetables are hydrogen1 oxygen1 and charcoal3 ,these are common to all vegetables1 and no vegetable can exist without them3 ,such other substances as exist in particular vegetables are only essential to the composition of those in which they are found1 and do not belong to vegetables in general4 ,of these elements1 hydrogen and oxygen have a strong tendency to unite with caloric1 and be converted into gas1 whilst charcoal is a fixed element1 having but little affinity with caloric4 ,on the other hand1 oxygen1 which1 in the usual temperature1 tends nearly equally to unite with hydrogen and with charcoal1 has a much stronger affinity with charcoal when at the red heat#bd1 and then unites with it to form carbonic acid4 ,although we are far from being able to appreciate all these powers of affinity1 or to express their proportional energy by numbers1 we are certain1 that1 however variable they may be when considered in relation to the quantity of caloric with which they are combined1 they are all nearly in equilibrium in the usual temperature of the atmosphere2 hence vegetables neither contain oil#be1 water1 nor carbonic acid1 tho' they contain all the elements of these substances4 ,the hydrogen is neither combined with the oxygen nor with the charcoal1 and reciprocally2 the particles of these three substances form a triple combination1 which remains in equilibrium whilst undisturbed by caloric but a very slight increase of temperature is sufficient to overturn this structure of combination4 ,if the increased temperature to which the vegetable is exposed does not exceed the heat of boiling water1 one part of the hydrogen combines with the oxygen1 and forms water1 the rest of the hydrogen combines with a part of the charcoal1 and forms volatile oil1 whilst the remainder of the charcoal1 being set free from its combination with the other elements1 remains fixed in the bottom of the distilling vessel4 ,when1 on the contrary1 we employ a red heat1 no water is formed1 or1 at least1 any that may have been produced by the first application of the heat is decomposed1 the oxygen having a greater affinity with the charcoal at this degree of heat1 combines with it to form carbonic acid1 and the hydrogen being left free from combination with the other elements1 unites with caloric1 and escapes in the state of hydrogen gas4 ,in this high temperature1 either no oil is formed1 or1 if any was produced during the lower temperature at the beginning of the experiment1 it is decomposed by the action of the red heat4 ,thus the decomposition of vegetable matter1 under a high temperature1 is produced by the action of double and triple affinities2 while the charcoal attracts the oxygen1 on purpose to form carbonic acid1 the caloric attracts the hydrogen1 and converts it into hydrogen gas4 ,the distillation of every species of vegetable substance confirms the truth of this theory1 if we can give that name to a simple relation of facts4 ,when sugar is submitted to distillation1 so long as we only employ a heat but a little below that of boiling water1 it only loses its water of cristallization1 it still remains sugar1 and retains all its properties2 but1 immediately upon raising the heat only a little above that degree1 it becomes blackened1 a part of the charcoal separates from the combination1 water slightly acidulated passes over accompanied by a little oil1 and the charcoal which remains in the retort is nearly a third part of the original weight of the sugar4 ,the operation of affinities which take place during the decomposition1 by fire1 of vegetables which contain azote1 such as the cruciferous plants1 and of those containing phosphorus1 is more complicated2 but1 as these substances only enter into the composition of vegetables in very small quantities1 they only1 apparently1 produce slight changes upon the products of distillation2 the phosphorus seems to combine with the charcoal1 and1 acquiring fixity from that union1 remains behind in the retort1 while the azote1 combining with a part of the hydrogen1 forms ammoniac1 or volatile alkali4 ,animal substances1 being composed nearly of the same elements with cruciferous plants1 give the same products in distillation1 with this difference1 that1 as they contain a greater quantity of hydrogen and azote1 they produce more oil and more ammoniac4 ,i shall only produce one fact as a proof of the exactness with which this theory explains all the phenomena which occur during the distillation of animal substances1 which is the rectification and total decomposition of volatile animal oil1 commonly known by the name of ,dippel's oil4 ,when these oils are procured by a first distillation in a naked fire they are brown1 from containing a little charcoal almost in a free state2 but they become quite colourless by rectification4 ,even in this state the charcoal in their composition has so slight a connection with the other elements as to separate by mere exposure to the air4 ,if we put a quantity of this animal oil1 well rectified1 and consequently clear1 limpid1 and transparent1 into a bell-glass filled with oxygen gas over mercury1 in a short time the gas is much diminished1 being absorbed by the oil1 the oxygen combining with the hydrogen of the oil forms water1 which sinks to the bottom1 at the same time the charcoal which was combined with the hydrogen being set free1 manifests itself by rendering the oil black4 ,hence the only way of preserving these oils colourless and transparent1 is by keeping them in bottles perfectly full and accurately corked1 to hinder the contact of air1 which always discolours them4 ,successive rectifications of this oil furnish another phenomenon confirming our theory4 ,in each distillation a small quantity of charcoal remains in the retort1 and a little water is formed by the union of the oxygen contained in the air of the distilling vessels with the hydrogen of the oil4 ,as this takes place in each successive distillation1 if we make use of large vessels and a considerable degree of heat1 we at last decompose the whole of the oil1 and change it entirely into water and charcoal4 ,when we use small vessels1 and especially when we employ a slow fire1 or degree of heat little above that of boiling water1 the total decomposition of these oils1 by repeated distillation1 is greatly more tedious1 and more difficultly accomplished4 ,i shall give a particular detail to the ,academy1 in a separate memoir1 of all my experiments upon the decomposition of oil2 but what ,i have related above may suffice to give just ideas of the composition of animal and vegetable substances1 and of their decomposition by the action of fire4 ,,footnotes3 #bd ,though this term1 red heat1 does not indicate any absolutely determinate degree of temperature1 ,i shall use it sometimes to express a temperature considerably above that of boiling water4--,a4 #be ,i must be understood here to speak of vegetables reduced to a perfectly dry state2 and1 with respect to oil1 ,i do not mean that which is procured by expression either in the cold1 or in a temperature not exceeding that of boiling water2 ,i only allude to the empyreumatic oil procured by distillation with a naked fire1 in a heat superior to the temperature of boiling water2 which is the only oil declared to be produced by the operation of fire4 ,what ,i have published upon this subject in the ,memoirs of the ,academy for #aghf may be consulted4--,a4 ,,chap4 ,,xiii4 ,of the ,decomposition of ,vegetable ,oxyds by the ,vinous ,fermentation4 ,the manner in which wine1 cyder1 mead1 and all the liquors formed by the spiritous fermentation1 are produced1 is well known to every one4 ,the juice of grapes or of apples being expressed1 and the latter being diluted with water1 they are put into large vats1 which are kept in a temperature of at least #aj 7#ed4e7 of the thermometer4 ,a rapid intestine motion1 or fermentation1 very soon takes place1 numerous globules of gas form in the liquid and burst at the surface2 when the fermentation is at its height1 the quantity of gas disengaged is so great as to make the liquor appear as if boiling violently over a fire4 ,when this gas is carefully gathered1 it is found to be carbonic acid perfectly pure1 and free from admixture with any other species of air or gas whatever4 ,when the fermentation is completed1 the juice of grapes is changed from being sweet1 and full of sugar1 into a vinous liquor which no longer contains any sugar1 and from which we procure1 by distillation1 an inflammable liquor1 known in commerce under the name of ,spirit of ,wine4 ,as this liquor is produced by the fermentation of any saccharine matter whatever diluted with water1 it must have been contrary to the principles of our nomenclature to call it spirit of wine rather than spirit of cyder1 or of fermented sugar2 wherefore1 we have adopted a more general term1 and the ,arabic word alkohol seems extremely proper for the purpose4 ,this operation is one of the most extraordinary in chemistry3 ,we must examine whence proceed the disengaged carbonic acid and the inflammable liquor produced1 and in what manner a sweet vegetable oxyd becomes thus converted into two such opposite substances1 whereof one is combustible1 and the other eminently the contrary4 ,to solve these two questions1 it is necessary to be previously acquainted with the analysis of the fermentable substance1 and of the products of the fermentation4 ,we may lay it down as an incontestible axiom1 that1 in all the operations of art and nature1 nothing is created2 an equal quantity of matter exists both before and after the experiment2 the quality and quantity of the elements remain precisely the same2 and nothing takes place beyond changes and modifications in the combination of these elements4 ,upon this principle the whole art of performing chemical experiments depends3 ,we must always suppose an exact equality between the elements of the body examined and those of the products of its analysis4 ,hence1 since from must of grapes we procure alkohol and carbonic acid1 ,i have an undoubted right to suppose that must consists of carbonic acid and alkohol4 ,from these premises1 we have two methods of ascertaining what passes during vinous fermentation1 by determining the nature of1 and the elements which compose1 the fermentable substances1 or by accurately examining the produces resulting from fermentation2 and it is evident that the knowledge of either of these must lead to accurate conclusions concerning the nature and composition of the other4 ,from these considerations1 it became necessary accurately to determine the constituent elements of the fermentable substances2 and1 for this purpose1 ,i did not make use of the compound juices of fruits1 the rigorous analysis of which is perhaps impossible1 but made choice of sugar1 which is easily analysed1 and the nature of which ,i have already explained4 ,this substance is a true vegetable oxyd with two bases1 composed of hydrogen and charcoal brought to the state of an oxyd1 by a certain proportion of oxygen2 and these three elements are combined in such a way1 that a very slight force is sufficient to destroy the equilibrium of their connection4 ,by a long train of experiments1 made in various ways1 and often repeated1 ,i ascertained that the proportion in which these ingredients exist in sugar1 are nearly eight parts of hydrogen1 #fd parts of oxygen1 and #bh parts of charcoal1 all by weight1 forming #ajj parts of sugar4 ,sugar must be mixed with about four times its weight of water1 to render it susceptible of fermentation2 and even then the equilibrium of its elements would remain undisturbed1 without the assistance of some substance1 to give a commencement to the fermentation4 ,this is accomplished by means of a little yeast from beer2 and1 when the fermentation is once excited1 it continues of itself until completed4 ,i shall1 in another place1 give an account of the effects of yeast1 and other ferments1 upon fermentable substances4 ,i have usually employed #aj libs4 of yeast1 in the state of paste1 for each #ajj libs4 of sugar1 with as much water as is four times the weight of the sugar4 ,i shall give the results of my experiments exactly as they were obtained1 preserving even the fractions produced by calculation4 ,,table ,i4 ,materials of ,fermentation4 libs4 oz4 gros grs4 ,water #djj #j #j #j ,sugar #ajj #j #j #j ,yeast in paste1 #aj libs4 ,water #g #c #f #dd composed of ,dry yeast #b #ab #a #bh ---------------------- ,total #eaj ,,table ,,ii4 ,constituent ,elements of the ,materials of ,fermentation4 libs4 oz4 gros grs4 #djg libs4 #c oz4 #f gros #dd grs4 ,hydrogen #fa #a #b #ga4dj of water1 composed of ,oxygen #cdf #b #c #dd4fj ,hydrogen #h #j #j #j #ajj libs4 sugar1 composed of ,oxygen #fd #j #j #j ,charcoal #bh #j #j #j ,hydrogen #j #d #e #i4cj #b libs4 #ab oz4 #a gros #bh grs4 of ,oxygen #a #aj #b #bh4gf dry yeast1 composed of ,charcoal #j #ab #d #ei ,azote #j #j #e #b4id ----------------------- ,total weight #eaj #j #j #j ,,table ,,iii4 ,recapitulation of these ,elements4 libs4 oz4 gros grs4 ,oxygen3 of the water #cdj #j #j #j of the water libs4 oz4 gros grs4 in the yeast #f #b #c #dd4fj #daa #ab #f #a4cf of the sugar #fd #j #j #j of the dry yeast #a #aj #b #bh4gf ,hydrogen3 of the water #fj #j #j #j of the water in the yeast #a #a #b #ga4dj #fi #f #j #h4gj of the sugar #h #j #j #j of the dry yeast #j #d #e #i4cj ,charcoal3 of the sugar #bh #j #j #j of the yeast #j #ab #d #ei4jj #bh #ab #d #ei4jj ,azote of the yeast - - - - #j #j #e #b4id -------------------------- ,in all #eaj #j #j #j ,having thus accurately determined the nature and quantity of the constituent elements of the materials submitted to fermentation1 we have next to examine the products resulting from that process4 ,for this purpose1 ,i placed the above #eaj libs4 of fermentable liquor in a proper#bf apparatus1 by means of which ,i could accurately determine the quantity and quality of gas disengaged during the fermentation1 and could even weigh every one of the products separately1 at any period of the process ,i judged proper4 ,an hour or two after the substances are mixed together1 especially if they are kept in a temperature of from #ae 7#fe4ge7 to #ah 7#gb4e7 of the thermometer1 the first marks of fermentation commence2 the liquor turns thick and frothy1 little globules of air are disengaged1 which rise and burst at the surface2 the quantity of these globules quickly increases1 and there is a rapid and abundant production of very pure carbonic acid1 accompanied with a scum1 which is the yeast separating from the mixture4 ,after some days1 less or more according to the degree of heat1 the intestine motion and disengagement of gas diminish2 but these do not cease entirely1 nor is the fermentation completed for a considerable time4 ,during the process1 #ce libs4 #e oz4 #d gros #ai grs4 of dry carbonic acid are disengaged1 which carry alongst with them #ac libs4 #ad oz4 #e gros of water4 ,there remains in the vessel #dfj libs4 #aa oz4 #f gros #ec grs4 of vinous liquor1 slightly acidulous4 ,this is at first muddy1 but clears of itself1 and deposits a portion of yeast4 ,when we separately analise all these substances1 which is effected by very troublesome processes1 we have the results as given in the following ,tables4 ,this process1 with all the subordinate calculations and analyses1 will be detailed at large in the ,memoirs of the ,academy4 ,,table ,,iv4 ,product of ,fermentation4 libs4 oz4 gros grs4 #ce libs4 #e oz4 #d gros #ai grs4 ,oxygen #be #g #a #cd of carbonic acid1 composed of ,charcoal #i #ad #b #eg #djh libs4 #ae oz4 #e gros #ad grs4 ,oxygen #cdg #aj #j #ei of water1 composed of ,hydrogen #fa #e #d #bg ,oxygen1 combined with hydrogen #ca #f #a #fd ,hydrogen1 combined #eg libs4 #aa oz4 #a gros #eh grs4 with oxygen #e #h #e #c of dry alkohol1 composed of ,hydrogen1 combined with charcoal #d #j #e #j ,charcoal1 combined with hydrogen #af #aa #e #fc #b libs4 #h oz4 of dry acetous ,hydrogen #j #b #d #j acid1 composed of ,oxygen #a #aa #d #j ,charcoal #j #aj #j #j #d libs4 #a oz4 #d gros #c grs4 ,hydrogen #j #e #a #fg of residuum of sugar1 ,oxygen #b #i #g #bg composed of ,charcoal #a #b #b #ec ,hydrogen #j #b #b #da #a lib4 #f oz4 #j gros #e grs4 ,oxygen #j #ac #a #ad of dry yeast1 composed of ,charcoal #j #f #b #cj ,azote #j #j #b #cg --- ----------------- #eaj libs4 ,total #eaj #j #j #j ,,table ,v4 ,recapitulation of the ,products4 ---------------------------------------- ------------------------------------ libs4 oz4 gros grs4 #dji libs4 #aj oz4 #j gros #ed grs4 ,water #cdg #aj #j #ei of oxygen contained in the ,carbonic acid #be #g #a #cd ,alkohol #ca #f #a #fd ,acetous acid #a #aa #d #j ,residuum of sugar #b #i #g #bg ,yeast #j #ac #a #ad #bh libs4 #ab oz4 #e gros #ei grs4 ,carbonic acid #i #ad #b #eg of charcoal contained ,alkohol #af #aa #e #fc in the ,acetous acid #j #aj #j #j ,residuum of sugar #a #b #b #ec ,yeast #j #f #b #cj ,water #fa #e #d #bg #ga libs4 #h oz4 #f gros #ff grs4 ,water of the alkohol #e #h #e #c of hydrogen contained ,combined with the in the charcoal of the alko4 #d #j #e #j ,acetous acid #j #b #d #j ,residuum of sugar #j #e #a #fg ,yeast #j #b #b #da #b gros #cg grs4 of azote in the yeast #j #j #b #cg --- --------------- #eaj libs4 ,total #eaj #j #j #j ,in these results1 ,i have been exact1 even to grains2 not that it is possible1 in experiments of this nature1 to carry our accuracy so far1 but as the experiments were made only with a few pounds of sugar1 and as1 for the sake of comparison1 ,i reduced the results of the actual experiments to the quintal or imaginary hundred pounds1 ,i thought it necessary to leave the fractional parts precisely as produced by calculation4 ,when we consider the results presented by these tables with attention1 it is easy to discover exactly what occurs during fermentation4 ,in the first place1 out of the #ajj libs4 of sugar employed1 #d libs4 #a oz4 #d gros #c grs4 remain1 without having suffered decomposition2 so that1 in reality1 we have only operated upon #ie libs4 #ad oz4 #c gros #fi grs4 of sugar2 that is to say1 upon #fa libs4 #f oz4 #de grs4 of oxygen1 #g libs4 #aj oz4 #f gros #f grs4 of hydrogen1 and #bf libs4 #ac oz4 #e gros #ai grs4 of charcoal4 ,by comparing these quantities1 we find that they are fully sufficient for forming the whole of the alkohol1 carbonic acid and acetous acid produced by the fermentation4 ,it is not1 therefore1 necessary to suppose that any water has been decomposed during the experiment1 unless it be pretended that the oxygen and hydrogen exist in the sugar in that state4 ,on the contrary1 ,i have already made it evident that hydrogen1 oxygen and charcoal1 the three constituent elements of vegetables1 remain in a state of equilibrium or mutual union with each other which subsists so long as this union remains undisturbed by increased temperature1 or by some new compound attraction2 and that then only these elements combine1 two and two together1 to form water and carbonic acid4 ,the effects of the vinous fermentation upon sugar is thus reduced to the mere separation of its elements into two portions2 one part is oxygenated at the expence of the other1 so as to form carbonic acid1 whilst the other part1 being deoxygenated in favour of the former1 is converted into the combustible substance alkohol2 therefore1 if it were possible to reunite alkohol and carbonic acid together1 we ought to form sugar4 ,it is evident that the charcoal and hydrogen in the alkohol do not exist in the state of oil1 they are combined with a portion of oxygen1 which renders them miscible with water2 wherefore these three substances1 oxygen1 hydrogen1 and charcoal1 exist here likewise in a species of equilibrium or reciprocal combination2 and in fact1 when they are made to pass through a red hot tube of glass or porcelain1 this union or equilibrium is destroyed1 the elements become combined1 two and two1 and water and carbonic acid are formed4 ,i had formally advanced1 in my first ,memoirs upon the formation of water1 that it was decomposed in a great number of chemical experiments1 and particularly during the vinous fermentation4 ,i then supposed that water existed ready formed in sugar1 though ,i am now convinced that sugar only contains the elements proper for composing it4 ,it may be readily conceived1 that it must have cost me a good deal to abandon my first notions1 but by several years reflection1 and after a great number of experiments and observations upon vegetable substances1 ,i have fixed my ideas as above4 ,i shall finish what ,i have to say upon vinous fermentation1 by observing1 that it furnishes us with the means of analysing sugar and every vegetable fermentable matter4 ,we may consider the substances submitted to fermentation1 and the products resulting from that operation1 as forming an algebraic equation2 and1 by successively supposing each of the elements in this equation unknown1 we can calculate their values in succession1 and thus verify our experiments by calculation1 and our calculation by experiment reciprocally4 ,i have often successfully employed this method for correcting the first results of my experiments1 and to direct me in the proper road for repeating them to advantage4 ,i have explained myself at large upon this subject1 in a ,memoir upon vinous fermentation already presented to the ,academy1 and which will speedily be published4 ,,footnotes3 #bf ,the above apparatus is described in the ,third ,part4--,a4 ,,chap4 ,,xiv4 ,of the ,putrefactive ,fermentation4 ,the phenomena of putrefaction are caused1 like those of vinous fermentation1 by the operation of very complicated affinities4 ,the constituent elements of the bodies submitted to this process cease to continue in equilibrium in the threefold combination1 and form themselves anew into binary combinations#bg1 or compounds1 consisting of two elements only2 but these are entirely different from the results produced by the vinous fermentation4 ,instead of one part of the hydrogen remaining united with part of the water and charcoal to form alkohol1 as in the vinous fermentation1 the whole of the hydrogen is dissipated1 during putrefaction1 in the form of hydrogen gas1 whilst1 at the same time1 the oxygen and charcoal1 uniting with caloric1 escape in the form of carbonic acid gas2 so that1 when the whole process is finished1 especially if the materials have been mixed with a sufficient quantity of water1 nothing remains but the earth of the vegetable mixed with a small portion of charcoal and iron4 ,thus putrefaction is nothing more than a complete analysis of vegetable substance1 during which the whole of the constituent elements is disengaged in form of gas1 except the earth1 which remains in the state of mould#bh4 ,such is the result of putrefaction when the substances submitted to it contain only oxygen1 hydrogen1 charcoal and a little earth4 ,but this case is rare1 and these substances putrify imperfectly and with difficulty1 and require a considerable time to complete their putrefaction4 ,it is otherwise with substances containing azote1 which indeed exists in all animal matters1 and even in a considerable number of vegetable substances4 ,this additional element is remarkably favourable to putrefaction2 and for this reason animal matter is mixed with vegetable1 when the putrefaction of these is wished to be hastened4 ,the whole art of forming composts and dunghills1 for the purposes of agriculture1 consists in the proper application of this admixture4 ,the addition of azote to the materials of putrefaction not only accelerates the process1 that element likewise combines with part of the hydrogen1 and forms a new substance called volatile alkali or ammoniac4 ,the results obtained by analysing animal matters1 by different processes1 leave no room for doubt with regard to the constituent elements of ammoniac2 whenever the azote has been previously separated from these substances1 no ammoniac is produced2 and in all cases they furnish ammoniac only in proportion to the azote they contain4 ,this composition of ammoniac is likewise fully proved by ,mr ,berthollet1 in the ,memoirs of the ,academy for #aghe1 p4 #caf4 where he gives a variety of analytical processes by which ammoniac is decomposed1 and its two elements1 azote and hydrogen1 procured separately4 ,i already mentioned in ,chap4 ,x4 that almost all combustible bodies were capable of combining with each other2 hydrogen gas possesses this quality in an eminent degree1 it dissolves charcoal1 sulphur1 and phosphorus1 producing the compounds named carbonated hydrogen gas1 sulphurated hydrogen gas1 and phosphorated hydrogen gas4 ,the two latter of these gasses have a peculiarly disagreeable flavour2 the sulphurated hydrogen gas has a strong resemblance to the smell of rotten eggs1 and the phosphorated smells exactly like putrid fish4 ,ammoniac has likewise a peculiar odour1 not less penetrating1 or less disagreeable1 than these other gasses4 ,from the mixture of these different flavours proceeds the fetor which accompanies the putrefaction of animal substances4 ,sometimes ammoniac predominates1 which is easily perceived by its sharpness upon the eyes2 sometimes1 as in feculent matters1 the sulphurated gas is most prevalent2 and sometimes1 as in putrid herrings1 the phosphorated hydrogen gas is most abundant4 ,i long supposed that nothing could derange or interrupt the course of putrefaction2 but ,mr ,fourcroy and ,mr ,thouret have observed some peculiar phenomena in dead bodies1 buried at a certain depth1 and preserved to a certain degree1 from contact with air2 having found the muscular flesh frequently converted into true animal fat4 ,this must have arisen from the disengagement of the azote1 naturally contained in the animal substance1 by some unknown cause1 leaving only the hydrogen and charcoal remaining1 which are the elements proper for producing fat or oil4 ,this observation upon the possibility of converting animal substances into fat may some time or other lead to discoveries of great importance to society4 ,the faeces of animals1 and other excrementitious matters1 are chiefly composed of charcoal and hydrogen1 and approach considerably to the nature of oil1 of which they furnish a considerable quantity by distillation with a naked fire2 but the intolerable foetor which accompanies all the products of these substances prevents our expecting that1 at least for a long time1 they can be rendered useful in any other way than as manures4 ,i have only given conjectural approximations in this ,chapter upon the composition of animal substances1 which is hitherto but imperfectly understood4 ,we know that they are composed of hydrogen1 charcoal1 azote1 phosphorus1 and sulphur1 all of which1 in a state of quintuple combination1 are brought to the state of oxyd by a larger or smaller quantity of oxygen4 ,we are1 however1 still unacquainted with the proportions in which these substances are combined1 and must leave it to time to complete this part of chemical analysis1 as it has already done with several others4 ,,footnotes3 #bg ,binary combinations are such as consist of two simple elements combined together4 ,ternary1 and quaternary1 consist of three and four elements4--,e4 #bh ,in the ,third ,part will be given the description of an apparatus proper for being used in experiments of this kind4--,a4 ,,chap4 ,,xv4 ,of the ,acetous ,fermentation4 ,the acetous fermentation is nothing more than the acidification or oxygenation of wine#bi1 produced in the open air by means of the absorption of oxygen4 ,the resulting acid is the acetous acid1 commonly called ,vinegar1 which is composed of hydrogen and charcoal united together in proportions not yet ascertained1 and changed into the acid state by oxygen4 ,as vinegar is an acid1 we might conclude from analogy that it contains oxygen1 but this is put beyond doubt by direct experiments3 ,in the first place1 we cannot change wine into vinegar without the contact of air containing oxygen2 secondly1 this process is accompanied by a diminution of the volume of the air in which it is carried on from the absorption of its oxygen2 and1 thirdly1 wine may be changed into vinegar by any other means of oxygenation4 ,independent of the proofs which these facts furnish of the acetous acid being produced by the oxygenation of wine1 an experiment made by ,mr ,chaptal1 ,professor of ,chemistry at ,montpellier1 gives us a distinct view of what takes place in this process4 ,he impregnated water with about its own bulk of carbonic acid from fermenting beer1 and placed this water in a cellar in vessels communicating with the air1 and in a short time the whole was converted into acetous acid4 ,the carbonic acid gas procured from beer vats in fermentation is not perfectly pure1 but contains a small quantity of alkohol in solution1 wherefore water impregnated with it contains all the materials necessary for forming the acetous acid4 ,the alkohol furnishes hydrogen and one portion of charcoal1 the carbonic acid furnishes oxygen and the rest of the charcoal1 and the air of the atmosphere furnishes the rest of the oxygen necessary for changing the mixture into acetous acid4 ,from this observation it follows1 that nothing but hydrogen is wanting to convert carbonic acid into acetous acid2 or more generally1 that1 by means of hydrogen1 and according to the degree of oxygenation1 carbonic acid may be changed into all the vegetable acids2 and1 on the contrary1 that1 by depriving any of the vegetable acids of their hydrogen1 they may be converted into carbonic acid4 ,although the principal facts relating to the acetous acid are well known1 yet numerical exactitude is still wanting1 till furnished by more exact experiments than any hitherto performed2 wherefore ,i shall not enlarge any farther upon the subject4 ,it is sufficiently shown by what has been said1 that the constitution of all the vegetable acids and oxyds is exactly conformable to the formation of vinegar2 but farther experiments are necessary to teach us the proportion of the constituent elements in all these acids and oxyds4 ,we may easily perceive1 however1 that this part of chemistry1 like all the rest of its divisions1 makes rapid progress towards perfection1 and that it is already rendered greatly more simple than was formerly believed4 ,,footnotes3 #bi ,the word ,wine1 in this chapter1 is used to signify the liquor produced by the vinous fermentation1 whatever vegetable substance may have been used for obtaining it4--,e4 ,,chap4 ,,xvi4 ,of the ,formation of ,neutral ,salts1 and of their different ,bases4 ,we have just seen that all the oxyds and acids from the animal and vegetable kingdoms are formed by means of a small number of simple elements1 or at least of such as have not hitherto been susceptible of decomposition1 by means of combination with oxygen2 these are azote1 sulphur1 phosphorus1 charcoal1 hydrogen1 and the muriatic radical#cj4 ,we may justly admire the simplicity of the means employed by nature to multiply qualities and forms1 whether by combining three or four acidifiable bases in different proportions1 or by altering the dose of oxygen employed for oxydating or acidifying them4 ,we shall find the means no less simple and diversified1 and as abundantly productive of forms and qualities1 in the order of bodies we are now about to treat of4 ,acidifiable substances1 by combining with oxygen1 and their consequent conversion into acids1 acquire great susceptibility of farther combination2 they become capable of uniting with earthy and metallic bodies1 by which means neutral salts are formed4 ,acids may therefore be considered as true salifying principles1 and the substances with which they unite to form neutral salts may be called salifiable bases3 ,the nature of the union which these two principles form with each other is meant as the subject of the present chapter4 ,this view of the acids prevents me from considering them as salts1 though they are possessed of many of the principal properties of saline bodies1 as solubility in water1 c4 ,i have already observed that they are the result of a first order of combination1 being composed of two simple elements1 or at least of elements which act as if they were simple1 and we may therefore rank them1 to use the language of ,stahl1 in the order of mixts4 ,the neutral salts1 on the contrary1 are of a secondary order of combination1 being formed by the union of two mixts with each other1 and may therefore be termed compounds4 ,hence ,i shall not arrange the alkalies#ca or earths in the class of salts1 to which ,i allot only such as are composed of an oxygenated substance united to a base4 ,i have already enlarged sufficiently upon the formation of acids in the preceding chapter1 and shall not add any thing farther upon that subject2 but having as yet given no account of the salifiable bases which are capable of uniting with them to form neutral salts1 ,i mean1 in this chapter1 to give an account of the nature and origin of each of these bases4 ,these are potash1 soda1 ammoniac1 lime1 magnesia1 barytes1 argill#cb1 and all the metallic bodies4 #a4 ,of ,potash4 ,we have already shown1 that1 when a vegetable substance is submitted to the action of fire in distilling vessels1 its component elements1 oxygen1 hydrogen1 and charcoal1 which formed a threefold combination in a state of equilibrium1 unite1 two and two1 in obedience to affinities which act conformable to the degree of heat employed4 ,thus1 at the first application of the fire1 whenever the heat produced exceeds the temperature of boiling water1 part of the oxygen and hydrogen unite to form water2 soon after the rest of the hydrogen1 and part of the charcoal1 combine into oil2 and1 lastly1 when the fire is pushed to the red heat1 the oil and water1 which had been formed in the early part of the process1 become again decomposed1 the oxygen and charcoal unite to form carbonic acid1 a large quantity of hydrogen gas is set free1 and nothing but charcoal remains in the retort4 ,a great part of these phenomena occur during the combustion of vegetables in the open air2 but1 in this case1 the presence of the air introduces three new substances1 the oxygen and azote of the air and caloric1 of which two at least produce considerable changes in the results of the operation4 ,in proportion as the hydrogen of the vegetable1 or that which results from the decomposition of the water1 is forced out in the form of hydrogen gas by the progress of the fire1 it is set on fire immediately upon getting in contact with the air1 water is again formed1 and the greater part of the caloric of the two gasses becoming free produces flame4 ,when all the hydrogen gas is driven out1 burnt1 and again reduced to water1 the remaining charcoal continues to burn1 but without flame2 it is formed into carbonic acid1 which carries off a portion of caloric sufficient to give it the gasseous form2 the rest of the caloric1 from the oxygen of the air1 being set free1 produces the heat and light observed during the combustion of charcoal4 ,the whole vegetable is thus reduced into water and carbonic acid1 and nothing remains but a small portion of gray earthy matter called ashes1 being the only really fixed principles which enter into the constitution of vegetables4 ,the earth1 or rather ashes1 which seldom exceeds a twentieth part of the weight of the vegetable1 contains a substance of a particular nature1 known under the name of fixed vegetable alkali1 or potash4 ,to obtain it1 water is poured upon the ashes1 which dissolves the potash1 and leaves the ashes which are insoluble2 by afterwards evaporating the water1 we obtain the potash in a white concrete form3 ,it is very fixed even in a very high degree of heat4 ,i do not mean here to describe the art of preparing potash1 or the method of procuring it in a state of purity1 but have entered upon the above detail that ,i might not use any word not previously explained4 ,the potash obtained by this process is always less or more saturated with carbonic acid1 which is easily accounted for3 ,as the potash does not form1 or at least is not set free1 but in proportion as the charcoal of the vegetable is converted into carbonic acid by the addition of oxygen1 either from the air or the water1 it follows1 that each particle of potash1 at the instant of its formation1 or at least of its liberation1 is in contact with a particle of carbonic acid1 and1 as there is a considerable affinity between these two substances1 they naturally combine together4 ,although the carbonic acid has less affinity with potash than any other acid1 yet it is difficult to separate the last portions from it4 ,the most usual method of accomplishing this is to dissolve the potash in water2 to this solution add two or three times its weight of quick-lime1 then filtrate the liquor and evaporate it in close vessels2 the saline substance left by the evaporation is potash almost entirely deprived of carbonic acid4 ,in this state it is soluble in an equal weight of water1 and even attracts the moisture of the air with great avidity2 by this property it furnishes us with an excellent means of rendering air or gas dry by exposing them to its action4 ,in this state it is soluble in alkohol1 though not when combined with carbonic acid2 and ,mr ,berthollet employs this property as a method of procuring potash in the state of perfect purity4 ,all vegetables yield less or more of potash in consequence of combustion1 but it is furnished in various degrees of purity by different vegetables2 usually1 indeed1 from all of them it is mixed with different salts from which it is easily separable4 ,we can hardly entertain a doubt that the ashes1 or earth which is left by vegetables in combustion1 pre-existed in them before they were burnt1 forming what may be called the skeleton1 or osseous part of the vegetable4 ,but it is quite otherwise with potash2 this substance has never yet been procured from vegetables but by means of processes or intermedia capable of furnishing oxygen and azote1 such as combustion1 or by means of nitric acid2 so that it is not yet demonstrated that potash may not be a produce from these operations4 ,i have begun a series of experiments upon this object1 and hope soon to be able to give an account of their results4 #b4 ,of ,soda4 ,soda1 like potash1 is an alkali procured by lixiviation from the ashes of burnt plants1 but only from those which grow upon the sea-side1 and especially from the herb kali1 whence is derived the name alkali1 given to this substance by the ,arabians4 ,it has some properties in common with potash1 and others which are entirely different3 ,in general1 these two substances have peculiar characters in their saline combinations which are proper to each1 and consequently distinguish them from each other2 thus soda1 which1 as obtained from marine plants1 is usually entirely saturated with carbonic acid1 does not attract the humidity of the atmosphere like potash1 but1 on the contrary1 desiccates1 its cristals effloresce1 and are converted into a white powder having all the properties of soda1 which it really is1 having only lost its water of cristallization4 ,hitherto we are not better acquainted with the constituent elements of soda than with those of potash1 being equally uncertain whether it previously existed ready formed in the vegetable or is a combination of elements effected by combustion4 ,analogy leads us to suspect that azote is a constituent element of all the alkalies1 as is the case with ammoniac2 but we have only slight presumptions1 unconfirmed by any decisive experiments1 respecting the composition of potash and soda4 #c4 ,of ,ammoniac4 ,we have1 however1 very accurate knowledge of the composition of ammoniac1 or volatile alkali1 as it is called by the old chemists4 ,mr ,berthollet1 in the ,memoirs of the ,academy for #aghd1 p4 #caf4 has proved by analysis1 that #ajjj parts of this substance consist of about #hjg parts of azote combined with #aic parts of hydrogen4 ,ammoniac is chiefly procurable from animal substances by distillation1 during which process the azote and hydrogen necessary to its formation unite in proper proportions2 it is not1 however1 procured pure by this process1 being mixed with oil and water1 and mostly saturated with carbonic acid4 ,to separate these substances it is first combined with an acid1 the muriatic for instance1 and then disengaged from that combination by the addition of lime or potash4 ,when ammoniac is thus produced in its greatest degree of purity it can only exist under the gasseous form1 at least in the usual temperature of the atmosphere1 it has an excessively penetrating smell1 is absorbed in large quantities by water1 especially if cold and assisted by compression4 ,water thus saturated with ammoniac has usually been termed volatile alkaline fluor2 we shall call it either simply ammoniac1 or liquid ammoniac1 and ammoniacal gas when it exists in the ariform state4 #d4 ,of ,lime1 ,magnesia1 ,barytes1 and ,argill4 ,the composition of these four earths is totally unknown1 and1 until by new discoveries their constituent elements are ascertained1 we are certainly authorised to consider them as simple bodies4 ,art has no share in the production of these earths1 as they are all procured ready formed from nature2 but1 as they have all1 especially the three first1 great tendency to combination1 they are never found pure4 ,lime is usually saturated with carbonic acid in the state of chalk1 calcarious spars1 most of the marbles1 c42 sometimes with sulphuric acid1 as in gypsum and plaster stones2 at other times with fluoric acid forming vitreous or fluor spars2 and1 lastly1 it is found in the waters of the sea1 and of saline springs1 combined with muriatic acid4 ,of all the salifiable bases it is the most universally spread through nature4 ,magnesia is found in mineral waters1 for the most part combined with sulphuric acid2 it is likewise abundant in sea-water1 united with muriatic acid2 and it exists in a great number of stones of different kinds4 ,barytes is much less common than the three preceding earths2 it is found in the mineral kingdom1 combined with sulphuric acid1 forming heavy spars1 and sometimes1 though rarely1 united to carbonic acid4 ,argill1 or the base of alum1 having less tendency to combination than the other earths1 is often found in the state of argill1 uncombined with any acid4 ,it is chiefly procurable from clays1 of which1 properly speaking1 it is the base1 or chief ingredient4 #e4 ,of ,metallic ,bodies4 ,the metals1 except gold1 and sometimes silver1 are rarely found in the mineral kingdom in their metallic state1 being usually less or more saturated with oxygen1 or combined with sulphur1 arsenic1 sulphuric acid1 muriatic acid1 carbonic acid1 or phosphoric acid4 ,metallurgy1 or the docimastic art1 teaches the means of separating them from these foreign matters2 and for this purpose we refer to such chemical books as treat upon these operations4 ,we are probably only acquainted as yet with a part of the metallic substances existing in nature1 as all those which have a stronger affinity to oxygen1 than charcoal possesses1 are incapable of being reduced to the metallic state1 and1 consequently1 being only presented to our observation under the form of oxyds1 are confounded with earths4 ,it is extremely probable that barytes1 which we have just now arranged with earths1 is in this situation2 for in many experiments it exhibits properties nearly approaching to those of metallic bodies4 ,it is even possible that all the substances we call earths may be only metallic oxyds1 irreducible by any hitherto known process4 ,those metallic bodies we are at present acquainted with1 and which we can reduce to the metallic or reguline state1 are the following seventeen3 #a4 ,arsenic4 #b4 ,molybdena4 #c4 ,tungstein4 #d4 ,manganese4 #e4 ,nickel4 #f4 ,cobalt4 #g4 ,bismuth4 #h4 ,antimony4 #i4 ,zinc4 #aj4 ,iron4 #aa4 ,tin4 #ab4 ,lead4 #ac4 ,copper4 #ad4 ,mercury4 #ae4 ,silver4 #af4 ,platina4 #ag4 ,gold4 ,i only mean to consider these as salifiable bases1 without entering at all upon the consideration of their properties in the arts1 and for the uses of society4 ,in these points of view each metal would require a complete treatise1 which would lead me far beyond the bounds ,i have prescribed for this work4 ,,footnotes3 #cj ,i have not ventured to omit this element1 as here enumerated with the other principles of animal and vegetable substances1 though it is not at all taken notice of in the preceding chapters as entering into the composition of these bodies4--,e4 #ca ,perhaps my thus rejecting the alkalies from the class of salts may be considered as a capital defect in the method ,i have adopted1 and ,i am ready to admit the charge2 but this inconvenience is compensated by so many advantages1 that ,i could not think it of sufficient consequence to make me alter my plan4--,a4 #cb ,called ,alumine by ,mr ,lavoisier2 but as ,argill has been in a manner naturalized to the language for this substance by ,mr ,kirwan1 ,i have ventured to use it in preference4--,e4 ,,chap4 ,,xvii4 ,continuation of the ,observations upon ,salifiable ,bases1 and the ,formation of ,neutral ,salts4 ,it is necessary to remark1 that earths and alkalies unite with acids to form neutral salts without the intervention of any medium1 whereas metallic substances are incapable of forming this combination without being previously less or more oxygenated2 strictly speaking1 therefore1 metals are not soluble in acids1 but only metallic oxyds4 ,hence1 when we put a metal into an acid for solution1 it is necessary1 in the first place1 that it become oxygenated1 either by attracting oxygen from the acid or from the water2 or1 in other words1 that a metal cannot be dissolved in an acid unless the oxygen1 either of the acid1 or of the water mixed with it1 has a stronger affinity to the metal than to the hydrogen or the acidifiable base2 or1 what amounts to the same thing1 that no metallic solution can take place without a previous decomposition of the water1 or the acid in which it is made4 ,the explanation of the principal phenomena of metallic solution depends entirely upon this simple observation1 which was overlooked even by the illustrious ,bergman4 ,the first and most striking of these is the effervescence1 or1 to speak less equivocally1 the disengagement of gas which takes place during the solution2 in the solutions made in nitric acid this effervescence is produced by the disengagement of nitrous gas2 in solutions with sulphuric acid it is either sulphurous acid gas or hydrogen gas1 according as the oxydation of the metal happens to be made at the expence of the sulphuric acid or of the water4 ,as both nitric acid and water are composed of elements which1 when separate1 can only exist in the gasseous form1 at least in the common temperature of the atmosphere1 it is evident that1 whenever either of these is deprived of its oxygen1 the remaining element must instantly expand and assume the state of gas2 the effervescence is occasioned by this sudden conversion from the liquid to the gasseous state4 ,the same decomposition1 and consequent formation of gas1 takes place when solutions of metals are made in sulphuric acid3 ,in general1 especially by the humid way1 metals do not attract all the oxygen it contains2 they therefore reduce it1 not into sulphur1 but into sulphurous acid1 and as this acid can only exist as gas in the usual temperature1 it is disengaged1 and occasions effervescence4 ,the second phenomenon is1 that1 when the metals have been previously oxydated1 they all dissolve in acids without effervescence3 ,this is easily explained2 because1 not having now any occasion for combining with oxygen1 they neither decompose the acid nor the water by which1 in the former case1 the effervescence is occasioned4 ,a third phenomenon1 which requires particular consideration1 is1 that none of the metals produce effervescence by solution in oxygenated muriatic acid4 ,during this process the metal1 in the first place1 carries off the excess of oxygen from the oxygenated muriatic acid1 by which it becomes oxydated1 and reduces the acid to the state of ordinary muriatic acid4 ,in this case there is no production of gas1 not that the muriatic acid does not tend to exist in the gasseous state in the common temperature1 which it does equally with the acids formerly mentioned1 but because this acid1 which otherwise would expand into gas1 finds more water combined with the oxygenated muriatic acid than is necessary to retain it in the liquid form2 hence it does not disengage like the sulphurous acid1 but remains1 and quietly dissolves and combines with the metallic oxyd previously formed from its superabundant oxygen4 ,the fourth phenomenon is1 that metals are absolutely insoluble in such acids as have their bases joined to oxygen by a stronger affinity than these metals are capable of exerting upon that acidifying principle4 ,hence silver1 mercury1 and lead1 in their metallic states1 are insoluble in muriatic acid1 but1 when previously oxydated1 they become readily soluble without effervescence4 ,from these phenomena it appears that oxygen is the bond of union between metals and acids2 and from this we are led to suppose that oxygen is contained in all substances which have a strong affinity with acids3 ,hence it is very probable the four eminently salifiable earths contain oxygen1 and their capability of uniting with acids is produced by the intermediation of that element4 ,what ,i have formerly noticed relative to these earths is considerably strengthened by the above considerations1 viz4 that they may very possibly be metallic oxyds1 with which oxygen has a stronger affinity than with charcoal1 and consequently not reducible by any known means4 ,all the acids hitherto known are enumerated in the following table1 the first column of which contains the names of the acids according to the new nomenclature1 and in the second column are placed the bases or radicals of these acids1 with observations4 ,names of the ,acids4 ,names of the ,bases1 with ,observations4 #a4 ,sulphurous ,sulphur4 #b4 ,sulphuric #c4 ,phosphorous ,phosphorus4 #d4 ,phosphoric #e4 ,muriatic ,muriatic radical or base1 hitherto unknown4 #f4 ,oxygenated muriatic #g4 ,nitrous #h4 ,nitric ,azote4 #i4 ,oxygenated nitric #aj4 ,carbonic ,charcoal ,the bases or radicals of all these acids #aa4 ,acetous seem to be formed by a combination #ab4 ,acetic of charcoal and hydrogen2 #ac4 ,oxalic and the only difference seems to be #ad4 ,tartarous owing to the different proportions in #ae4 ,pyro-tartarous which these elements combine to form #af4 ,citric their bases1 and to the different doses #ag4 ,malic of oxygen in their acidification4 ,a #ah4 ,pyro-lignous connected series of accurate experiments #ai4 ,pyro-mucous is still wanted upon this subject4 #bj4 ,gallic ,our knowledge of the bases of #ba4 ,prussic these acids is hitherto imperfect2 we #bb4 ,benzoic only know that they contain hydrogen #bc4 ,succinic and charcoal as principal elements1 #bd4 ,camphoric and that the prussic acid contains #be4 ,lactic azote4 #bf4 ,saccholactic #bg4 ,bombic ,the base of these and all acids #bh4 ,formic procured from animal substances seems #bi4 ,sebacic to consist of charcoal1 hydrogen1 phosphorous1 and azote4 #cj4 ,boracic ,the bases of these two are hitherto #ca4 ,fluoric entirely unknown4 #cb4 ,antimonic ,antimony4 #cc4 ,argentic ,silver4 #cd4 ,arseniac7,a7 ,arsenic4 #ce4 ,bismuthic ,bismuth4 #cf4 ,cobaltic ,cobalt4 #cg4 ,cupric ,copper4 #ch4 ,stannic ,tin4 #ci4 ,ferric ,iron4 #dj4 ,manganic ,manganese4 #da4 ,mercuric7,b7 ,mercury4 #db4 ,molybdic ,molybdena4 #dc4 ,nickolic ,nickel4 #dd4 ,auric ,gold4 #de4 ,platinic ,platina4 #df4 ,plumbic ,lead4 #dg4 ,tungstic ,tungstein4 #dh4 ,zincic ,zinc4 ,note ,a3 ,this term swerves a little from the rule in making the name of this acid terminate in ac instead of ic4 ,the base and acid are distinguished in ,french by arsenic and arsenique2 but1 having chosen the ,english termination ic to translate the ,french ique1 ,i was obliged to use this small deviation4--,e4 ,note ,b3 ,mr ,lavoisier has hydrargirique2 but mercurius being used for the base or metal1 the name of the acid1 as above1 is equally regular1 and less harsh4--,e4 ,in this list1 which contains #dh acids1 ,i have enumerated #ag metallic acids hitherto very imperfectly known1 but upon which ,mr ,berthollet is about to publish a very important work4 ,it cannot be pretended that all the acids which exist in nature1 or rather all the acidifiable bases1 are yet discovered2 but1 on the other hand1 there are considerable grounds for supposing that a more accurate investigation than has hitherto been attempted will diminish the number of the vegetable acids1 by showing that several of these1 at present considered as distinct acids1 are only modifications of others4 ,all that can be done in the present state of our knowledge is1 to give a view of chemistry as it really is1 and to establish fundamental principles1 by which such bodies as may be discovered in future may receive names1 in conformity with one uniform system4 ,the known salifiable bases1 or substances capable of being converted into neutral salts by union with acids1 amount to #bd2 viz4 #c alkalies1 #d earths1 and #ag metallic substances2 so that1 in the present state of chemical knowledge1 the whole possible number of neutral salts amounts to #aaebcc4 ,this number is upon the supposition that the metallic acids are capable of dissolving other metals1 which is a new branch of chemistry not hitherto investigated1 upon which depends all the metallic combinations named vitreous4 ,there is reason to believe that many of these supposable saline combinations are not capable of being formed1 which must greatly reduce the real number of neutral salts producible by nature and art4 ,even if we suppose the real number to amount only to five or six hundred species of possible neutral salts1 it is evident that1 were we to distinguish them1 after the manner of the ancients1 either by the names of their first discoverers1 or by terms derived from the substances from which they are procured1 we should at last have such a confusion of arbitrary designations1 as no memory could possibly retain4 ,this method might be tolerable in the early ages of chemistry1 or even till within these twenty years1 when only about thirty species of salts were known2 but1 in the present times1 when the number is augmenting daily1 when every new acid gives us #bd or #dh new salts1 according as it is capable of one or two degrees of oxygenation1 a new method is certainly necessary4 ,the method we have adopted1 drawn from the nomenclature of the acids1 is perfectly analogical1 and1 following nature in the simplicity of her operations1 gives a natural and easy nomenclature applicable to every possible neutral salt4 ,in giving names to the different acids1 we express the common property by the generical term acid1 and distinguish each species by the name of its peculiar acidifiable base4 ,hence the acids formed by the oxygenation of sulphur1 phosphorus1 charcoal1 c4 are called sulphuric acid1 phosphoric acid1 carbonic acid1 c4 ,we thought it likewise proper to indicate the different degrees of saturation with oxygen1 by different terminations of the same specific names4 ,hence we distinguish between sulphurous and sulphuric1 and between phosphorous and phosphoric acids1 c4 ,by applying these principles to the nomenclature of neutral salts1 we give a common term to all the neutral salts arising from the combination of one acid1 and distinguish the species by adding the name of the salifiable base4 ,thus1 all the neutral salts having sulphuric acid in their composition are named sulphats2 those formed by the phosphoric acid1 phosphats1 c4 ,the species being distinguished by the names of the salifiable bases gives us sulphat of potash1 sulphat of soda1 sulphat of ammoniac1 sulphat of lime1 sulphat of iron1 c4 ,as we are acquainted with #bd salifiable bases1 alkaline1 earthy1 and metallic1 we have consequently #bd sulphats1 as many phosphats1 and so on through all the acids4 ,sulphur is1 however1 susceptible of two degrees of oxygenation1 the first of which produces sulphurous1 and the second1 sulphuric acid2 and1 as the neutral salts produced by these two acids1 have different properties1 and are in fact different salts1 it becomes necessary to distinguish these by peculiar terminations2 we have therefore distinguished the neutral salts formed by the acids in the first or lesser degree of oxygenation1 by changing the termination at into ite1 as sulphites1 phosphites#cd1 c4 ,thus1 oxygenated or acidified sulphur1 in its two degrees of oxygenation is capable of forming #dh neutral salts1 #bd of which are sulphites1 and as many sulphats2 which is likewise the case with all the acids capable of two degrees of oxygenation#ce4 ,it were both tiresome and unnecessary to follow these denominations through all the varieties of their possible application2 it is enough to have given the method of naming the various salts1 which1 when once well understood1 is easily applied to every possible combination4 ,the name of the combustible and acidifiable body being once known1 the names of the acid it is capable of forming1 and of all the neutral combinations the acid is susceptible of entering into1 are most readily remembered4 ,such as require a more complete illustration of the methods in which the new nomenclature is applied will1 in the ,second ,part of this book1 find ,tables which contain a full enumeration of all the neutral salts1 and1 in general1 all the possible chemical combinations1 so far as is consistent with the present state of our knowledge4 ,to these ,i shall subjoin short explanations1 containing the best and most simple means of procuring the different species of acids1 and some account of the general properties of the neutral salts they produce4 ,i shall not deny1 that1 to render this work more complete1 it would have been necessary to add particular observations upon each species of salt1 its solubility in water and alkohol1 the proportions of acid and of salifiable base in its composition1 the quantity of its water of cristallization1 the different degrees of saturation it is susceptible of1 and1 finally1 the degree of force or affinity with which the acid adheres to the base4 ,this immense work has been already begun by ,messrs ,bergman1 ,morveau1 ,kirwan1 and other celebrated chemists1 but is hitherto only in a moderate state of advancement1 even the principles upon which it is founded are not perhaps sufficiently accurate4 ,these numerous details would have swelled this elementary treatise to much too great a size2 besides that1 to have gathered the necessary materials1 and to have completed all the series of experiments requisite1 must have retarded the publication of this book for many years4 ,this is a vast field for employing the zeal and abilities of young chemists1 whom ,i would advise to endeavour rather to do well than to do much1 and to ascertain1 in the first place1 the composition of the acids1 before entering upon that of the neutral salts4 ,every edifice which is intended to resist the ravages of time should be built upon a sure foundation2 and1 in the present state of chemistry1 to attempt discoveries by experiments1 either not perfectly exact1 or not sufficiently rigorous1 will serve only to interrupt its progress1 instead of contributing to its advancement4 ,,footnotes3 #cc ,this number excludes all triple salts1 or such as contain more than one salifiable base1 all the salts whose bases are over or under saturated with acid1 and those formed by the nitro-muriatic acid4--,e4 #cd ,as all the specific names of the acids in the new nomenclature are adjectives1 they would have applied severally to the various salifiable bases1 without the invention of other terms1 with perfect distinctness4 ,thus1 sulphurous potash1 and sulphuric potash1 are equally distinct as sulphite of potash1 and sulphat of potash2 and have the advantage of being more easily retained in the memory1 because more naturally arising from the acids themselves1 than the arbitrary terminations adopted by ,mr ,lavoisier4--,e4 #ce ,there is yet a third degree of oxygenation of acids1 as the oxygenated muriatic and oxygenated nitric acids4 ,the terms applicable to the neutral salts resulting from the union of these acids with salifiable bases is supplied by the ,author in the ,second ,part of this ,work4 ,these are formed by prefixing the word oxygenated to the name of the salt produced by the second degree of oxygenation4 ,thus1 oxygenated muriat of potash1 oxygenated nitrat of soda1 c4--,e4 ,,part ,,ii4 ,of the ,combination of ,acids with ,salifiable ,bases1 and of the ,formation of ,neutral ,salts4 ,,introduction4 ,if ,i had strictly followed the plan ,i at first laid down for the conduct of this work1 ,i would have confined myself1 in the ,tables and accompanying observations which compose this ,second ,part1 to short definitions of the several known acids1 and abridged accounts of the processes by which they are obtainable1 with a mere nomenclature or enumeration of the neutral salts which result from the combination of these acids with the various salifiable bases4 ,but ,i afterwards found that the addition of similar ,tables of all the simple substances which enter into the composition of the acids and oxyds1 together with the various possible combinations of these elements1 would add greatly to the utility of this work1 without being any great increase to its size4 ,these additions1 which are all contained in the twelve first sections of this ,part1 and the ,tables annexed to these1 form a kind of recapitulation of the first fifteen ,chapters of the ,first ,part3 ,the rest of the ,tables and ,sections contain all the saline combinations4 ,it must be very apparent that1 in this ,part of the ,work1 ,i have borrowed greatly from what has been already published by ,mr de ,morveau in the ,first ,volume of the ,encyclopedie par ordre des ,matires4 ,i could hardly have discovered a better source of information1 especially when the difficulty of consulting books in foreign languages is considered4 ,i make this general acknowledgment on purpose to save the trouble of references to ,mr de ,morveau's work in the course of the following part of mine4 ,,table ,,of ,,simple ,,substances4 ,simple substances belonging to all the kingdoms of nature1 which may be considered as the elements of bodies4 ,new ,names4 ,correspondent old ,names4 ,light ,light4 ,caloric ,heat4 ,principle or element of heat4 ,fire4 ,igneous fluid4 ,matter of fire and of heat4 ,oxygen ,dephlogisticated air4 ,empyreal air4 ,vital air1 or ,base of vital air4 ,azote ,phlogisticated air or gas4 ,mephitis1 or its base4 ,hydrogen ,inflammable air or gas1 or the base of inflammable air4 ,oxydable and ,acidifiable simple ,substance not ,metallic4 ,new ,names4 ,correspondent old names4 ,sulphur ,phosphorous ,the same names4 ,charcoal ,muriatic radical ,fluoric radical ,still unknown4 ,boracic radical ,oxydable and ,acidifiable simple ,metallic ,bodies ,new ,names4 ,correspondent ,old ,names4 ,antimony ,antimony4 ,arsenic ,arsenic4 ,bismuth ,bismuth4 ,cobalt ,cobalt4 ,copper ,copper4 ,gold ,gold4 ,iron ,iron4 ,lead ,regulus of ,lead4 ,manganese ,manganese4 ,mercury ,mercury4 ,molybdena ,molybdena4 ,nickel ,nickel4 ,platina ,platina4 ,silver ,silver4 ,tin ,tin4 ,tungstein ,tungstein4 ,zinc ,zinc4 ,salifiable simple ,earthy ,substances4 ,new ,names4 ,correspondent old ,names4 ,lime ,chalk1 calcareous earth4 ,quicklime4 ,magnesia ,magnesia1 base of ,epsom salt4 ,calcined or caustic magnesia4 ,barytes ,barytes1 or heavy earth4 ,argill ,clay1 earth of alum4 ,silex ,siliceous or vitrifiable earth4 ,,sect4 ,i4--,observations upon the ,table of ,simple ,substances4 ,the principle object of chemical experiments is to decompose natural bodies1 so as separately to examine the different substances which enter into their composition4 ,by consulting chemical systems1 it will be found that this science of chemical analysis has made rapid progress in our own times4 ,formerly oil and salt were considered as elements of bodies1 whereas later observation and experiment have shown that all salts1 instead of being simple1 are composed of an acid united to a base4 ,the bounds of analysis have been greatly enlarged by modern discoveries#cf2 the acids are shown to be composed of oxygen1 as an acidifying principle common to all1 united in each to a particular base4 ,i have proved what ,mr ,haffenfratz had before advanced1 that these radicals of the acids are not all simple elements1 many of them being1 like the oily principle1 composed of hydrogen and charcoal4 ,even the bases of neutral salts have been proved by ,mr ,berthollet to be compounds1 as he has shown that ammoniac is composed of azote and hydrogen4 ,thus1 as chemistry advances towards perfection1 by dividing and subdividing1 it is impossible to say where it is to end2 and these things we at present suppose simple may soon be found quite otherwise4 ,all we dare venture to affirm of any substance is1 that it must be considered as simple in the present state of our knowledge1 and so far as chemical analysis has hitherto been able to show4 ,we may even presume that the earths must soon cease to be considered as simple bodies2 they are the only bodies of the salifiable class which have no tendency to unite with oxygen2 and ,i am much inclined to believe that this proceeds from their being already saturated with that element4 ,if so1 they will fall to be considered as compounds consisting of simple substances1 perhaps metallic1 oxydated to a certain degree4 ,this is only hazarded as a conjecture2 and ,i trust the reader will take care not to confound what ,i have related as truths1 fixed on the firm basis of observation and experiment1 with mere hypothetical conjectures4 ,the fixed alkalies1 potash1 and soda1 are omitted in the foregoing ,table1 because they are evidently compound substances1 though we are ignorant as yet what are the elements they are composed of4 ,,table of compound oxydable and acidifiable bases4 ,names of the radicals4 ,oxydable or acidifiable ,nitro-muriatic radical or base1 from the mineral base of the acid formerly kingdom4 called aqua regia4 ,tartarous radical or base4 ,malic4 ,citric4 ,pyro-lignous4 ,oxydable or acidifiable ,pyro-mucous4 hydro-carbonous or ,pyro-tartarous4 carbono-hydrous radicals ,oxalic4 from the vegetable ,acetous4 kingdom4 ,succinic4 ,radicals ,benzoic4 ,camphoric4 ,gallic4 ,oxydable or acidifiable ,lactic4 radicals from the animal ,saccholactic4 kingdom1 which ,formic4 mostly contain azote1 ,bombic4 and frequently phosphorus4 ,sebacic4 ,lithic4 ,prussic4 ,note4--,the radicals from the vegetable kingdom are converted by a first degree of oxygenation into vegetable oxyds1 such as sugar1 starch1 and gum or mucus3 ,those of the animal kingdom by the same means form animal oxyds1 as lymph1 c4--,a4 ,,sect4 ,,ii4--,observations upon the ,table of ,compound ,radicals4 ,the older chemists being unacquainted with the composition of acids1 and not suspecting them to be formed by a peculiar radical or base for each1 united to an acidifying principle or element common to all1 could not consequently give any name to substances of which they had not the most distant idea4 ,we had therefore to invent a new nomenclature for this subject1 though we were at the same time sensible that this nomenclature must be susceptible of great modification when the nature of the compound radicals shall be better understood#cg4 ,the compound oxydable and acidifiable radicals from the vegetable and animal kingdoms1 enumerated in the foregoing table1 are not hitherto reducible to systematic nomenclature1 because their exact analysis is as yet unknown4 ,we only know in general1 by some experiments of my own1 and some made by ,mr ,hassenfratz1 that most of the vegetable acids1 such as the tartarous1 oxalic1 citric1 malic1 acetous1 pyro-tartarous1 and pyromucous1 have radicals composed of hydrogen and charcoal1 combined in such a way as to form single bases1 and that these acids only differ from each other by the proportions in which these two substances enter into the composition of their bases1 and by the degree of oxygenation which these bases have received4 ,we know farther1 chiefly from the experiments of ,mr ,berthollet1 that the radicals from the animal kingdom1 and even some of those from vegetables1 are of a more compound nature1 and1 besides hydrogen and charcoal1 that they often contain azote1 and sometimes phosphorus2 but we are not hitherto possessed of sufficiently accurate experiments for calculating the proportions of these several substances4 ,we are therefore forced1 in the manner of the older chemists1 still to name these acids after the substances from which they are procured4 ,there can be little doubt that these names will be laid aside when our knowledge of these substances becomes more accurate and extensive2 the terms hydro-carbonous1 hydro-carbonic1 carbono-hydrous1 and carbono hydric#ch1 will then become substituted for those we now employ1 which will then only remain as testimonies of the imperfect state in which this part of chemistry was transmitted to us by our predecessors4 ,it is evident that the oils1 being composed of hydrogen and charcoal combined1 are true carbono-hydrous or hydro-carbonous radicals2 and1 indeed1 by adding oxygen1 they are convertible into vegetable oxyds and acids1 according to their degrees of oxygenation4 ,we cannot1 however1 affirm that oils enter in their entire state into the composition of vegetable oxyds and acids2 it is possible that they previously lose a part either of their hydrogen or charcoal1 and that the remaining ingredients no longer exist in the proportions necessary to constitute oils4 ,we still require farther experiments to elucidate these points4 ,properly speaking1 we are only acquainted with one compound radical from the mineral kingdom1 the nitro-muriatic1 which is formed by the combination of azote with the muriatic radical4 ,the other compound mineral acids have been much less attended to1 from their producing less striking phenomena4 ,,sect4 ,,iii4--,observations upon the ,combinations of ,light and ,caloric with different ,substances4 ,i have not constructed any table of the combinations of light and caloric with the various simple and compound substances1 because our conceptions of the nature of these combinations are not hitherto sufficiently accurate4 ,we know1 in general1 that all bodies in nature are imbued1 surrounded1 and penetrated in every way with caloric1 which fills up every interval left between their particles2 that1 in certain cases1 caloric becomes fixed in bodies1 so as to constitute a part even of their solid substance1 though it more frequently acts upon them with a repulsive force1 from which1 or from its accumulation in bodies to a greater or lesser degree1 the transformation of solids into fluids1 and of fluids to ariform elasticity1 is entirely owing4 ,we have employed the generic name gas to indicate this ariform state of bodies produced by a sufficient accumulation of caloric2 so that1 when we wish to express the ariform state of muriatic acid1 carbonic acid1 hydrogen1 water1 alkohol1 c4 we do it by adding the word gas to their names2 thus muriatic acid gas1 carbonic acid gas1 hydrogen gas1 aqueous gas1 alkoholic gas1 c4 ,the combinations of light1 and its mode of acting upon different bodies1 is still less known4 ,by the experiments of ,mr ,berthollet1 it appears to have great affinity with oxygen1 is susceptible of combining with it1 and contributes alongst with caloric to change it into the state of gas4 ,experiments upon vegetation give reason to believe that light combines with certain parts of vegetables1 and that the green of their leaves1 and the various colours of their flowers1 is chiefly owing to this combination4 ,this much is certain1 that plants which grow in darkness are perfectly white1 languid1 and unhealthy1 and that to make them recover vigour1 and to acquire their natural colours1 the direct influence of light is absolutely necessary4 ,somewhat similar takes place even upon animals3 ,mankind degenerate to a certain degree when employed in sedentary manufactures1 or from living in crowded houses1 or in the narrow lanes of large cities2 whereas they improve in their nature and constitution in most of the country labours which are carried on in the open air4 ,organization1 sensation1 spontaneous motion1 and all the operations of life1 only exist at the surface of the earth1 and in places exposed to the influence of light4 ,without it nature itself would be lifeless and inanimate4 ,by means of light1 the benevolence of the ,deity hath filled the surface of the earth with organization1 sensation1 and intelligence4 ,the fable of ,promotheus might perhaps be considered as giving a hint of this philosophical truth1 which had even presented itself to the knowledge of the ancients4 ,i have intentionally avoided any disquisitions relative to organized bodies in this work1 for which reason the phenomena of respiration1 sanguification1 and animal heat1 are not considered2 but ,i hope1 at some future time1 to be able to elucidate these curious subjects4 ,trancriber's note3 ,the following table is presented in four sections to comply with #ge character line limitation4 ,,table of the binary ,combinations of ,oxygen with simple ,substances ---------------------------------------- ----------------------------- ,names of ,first degree of oxygenation4 the simple ---------------------------------------- substances4 ,new ,names4 ,ancient ,names4 ---------------------------------------- ---------------- ,caloric ,oxygen gas ,vital or dephlogisticated air ,hydrogen4 ,water7,a74 ,azote ,nitrous oxyd1 or ,nitrous gas or air base of nitrous gas ,charcoal ,oxyd of charcoal1 or,unknown ,combinations carbonic oxyd of oxygen with ,sulphur ,oxyd of sulphur ,soft sulphur simple non-metallic,phosphorus ,oxyd of phosphorus ,residuum from the substances4 combustion of phosphorus ,muriatic radical,muriatic oxyd ,unknown ,fluoric radical ,fluoric oxyd ,unknown ,boracic radical ,boracic oxyd ,unknown ---------------------------------------- -------------------------------- ,antimony ,grey oxyd of ,grey calx of antimony antimony ,silver ,oxyd of silver ,calx of silver ,arsenic ,grey oxyd of arsenic,grey calx of arsenic ,bismuth ,grey oxyd of bismuth,grey calx of bismuth ,cobalt ,grey oxyd of cobalt ,grey calx of cobalt ,copper ,brown oxyd of copper,brown calx of copper ,tin ,grey oxyd of tin ,grey calx of tin ,iron ,black oxyd of iron ,martial ethiops ,combinations of oxygen ,manganese ,black oxyd of ,black calx of with the manganese manganese simple metallic ,mercury ,black oxyd of ,ethiops mineral7,b7 substances4 mercury ,molybdena ,oxyd of molybdena ,calx of molybdena ,nickel ,oxyd of nickel ,calx of nickel ,gold ,yellow oxyd of gold ,yellow calx of gold ,platina ,yellow oxyd of ,yellow calx of platina platina ,lead ,grey oxyd of lead ,grey calx of lead ,tungstein ,oxyd of ,tungstein ,calx of ,tungstein ,zinc ,grey oxyd of zinc ,grey calx of zinc ---------------------------------------- ---------------------------- ---------------------------------------- ----------------------------- ,names of ,second degree of oxygenation4 the simple ---------------------------------------- substances4 ,new ,names4 ,ancient ,names4 ---------------------------------------- ---------------- ,caloric ,hydrogen4 ,azote ,nitrous acid ,smoaking nitrous acid ,charcoal ,carbonous acid ,unknown ,combinations of oxygen ,sulphur ,sulphurous acid ,sulphureous acid with simple non-metallic,phosphorus ,phosphorous acid ,volatile acid of substances4 phosphorus ,muriatic radical,muriatous acid ,unknown ,fluoric radical ,fluorous acid ,unknown ,boracic radical ,boracous acid ,unknown ---------------------------------------- -------------------------------- ,antimony ,white oxyd of ,white calx of antimony antimony diaphoretic antimony ,silver ,arsenic ,white oxyd of ,white calx of arsenic arsenic ,bismuth ,white oxyd of ,white calx of bismuth bismuth ,cobalt ,copper ,blue and green oxyds,blue and green of copper calces of copper ,tin ,white oxyd of tin ,white calx of tin1 or putty of tin ,iron ,yellow and red oxyds,ochre and rust of of iron iron ,combinations of oxygen ,manganese ,white oxyd of ,white calx of with the manganese manganese simple metallic ,mercury ,yellow and red oxyds,turbith mineral1 substances4 of mercury red precipitate1 calcinated mercury1 precipitate per se ,molybdena ,nickel ,gold ,red oxyd of gold ,red calx of gold1 purple precipitate of cassius ,platina ,lead ,yellow and red oxyds,massicot and minium of lead ,tungstein ,zinc ,white oxyd of zinc ,white calx of zinc1 pompholix ---------------------------------------- ---------------------------- ---------------------------------------- ----------------------------- ,names of ,third degree of oxygenation4 the simple ---------------------------------------- substances4 ,new ,names4 ,ancient ,names4 ---------------------------------------- ---------------- ,caloric ,hydrogen4 ,azote ,nitric acid ,pale1 or not smoaking nitrous acid ,combinations,charcoal ,carbonic acid ,fixed air of oxygen with ,sulphur ,sulphuric acid ,vitriolic acid simple non-metallic,phosphorus ,phosphoric acid ,phosphoric acid substances4 ,muriatic radical,muriatic acid ,marine acid ,fluoric radical ,fluoric acid ,unknown till lately ,boracic radical ,boracic acid ,homberg's sedative salt ---------------------------------------- -------------------------------- ,antimony ,antimonic acid ,silver ,argentic acid ,arsenic ,arseniac acid ,acid of arsenic ,bismuth ,bismuthic acid ,cobalt ,cobaltic acid ,copper ,cupric acid ,tin ,stannic acid ,iron ,ferric acid ,combinations of oxygen ,manganese ,manganesic acid with the simple metallic ,mercury ,mercuric acid substances4 ,molybdena ,molybdic acid ,acid of molybdena ,nickel ,nickelic acid ,gold ,auric acid ,platina ,platinic acid ,lead ,plumbic acid ,tungstein ,tungstic acid ,acid of ,tungstein ,zinc ,zincic acid ---------------------------------------- ---------------------------- ---------------------------------------- ------------------------------ ,names of ,fourth degree of oxygenation4 the simple ---------------------------------------- - substances4 ,new ,names4 ,ancient ,names4 ---------------------------------------- ----------------- ,caloric ,hydrogen4 ,azote ,oxygenated nitric ,unknown acid ,charcoal ,oxygenated carbonic ,unknown ,combinations acid of oxygen with ,sulphur ,oxygenated sulphuric ,unknown simple acid non-metallic,phosphorus ,oxygenated phosphoric,unknown substances4 acid ,muriatic radical,oxygenated muriatic ,dephlogisticated acid marine acid ,fluoric radical ,boracic radical ---------------------------------------- -------------------------------- ,antimony ,silver ,arsenic ,oxygenated arseniac ,unknown acid ,bismuth ,cobalt ,copper ,tin ,iron ,combinations of oxygen ,manganese with the simple metallic ,mercury substances4 ,molybdena ,oxygenated molybdic ,unknown acid ,nickel ,gold ,platina ,lead ,tungstein ,oxygenated ,tungstic ,unknown acid ,zinc ---------------------------------------- ----------------------------- ,note ,a3 ,only one degree of oxygenation of hydrogen is hitherto known4--,a4 ,note ,b3 ,ethiops mineral is the sulphuret of mercury2 this should have been called black precipitate of mercury4--,e4 ,,sect4 ,,iv4--,observations upon the ,combinations of ,oxygen with the simple ,substances4 ,oxygen forms almost a third of the mass of our atmosphere1 and is consequently one of the most plentiful substances in nature4 ,all the animals and vegetables live and grow in this immense magazine of oxygen gas1 and from it we procure the greatest part of what we employ in experiments4 ,so great is the reciprocal affinity between this element and other substances1 that we cannot procure it disengaged from all combination4 ,in the atmosphere it is united with caloric1 in the state of oxygen gas1 and this again is mixed with about two thirds of its weight of azotic gas4 ,several conditions are requisite to enable a body to become oxygenated1 or to permit oxygen to enter into combination with it4 ,in the first place1 it is necessary that the particles of the body to be oxygenated shall have less reciprocal attraction with each other than they have for the oxygen1 which otherwise cannot possibly combine with them4 ,nature1 in this case1 may be assisted by art1 as we have it in our power to diminish the attraction of the particles of bodies almost at will by heating them1 or1 in other words1 by introducing caloric into the interstices between their particles2 and1 as the attraction of these particles for each other is diminished in the inverse ratio of their distance1 it is evident that there must be a certain point of distance of particles when the affinity they possess with each other becomes less than that they have for oxygen1 and at which oxygenation must necessarily take place if oxygen be present4 ,we can readily conceive that the degree of heat at which this phenomenon begins must be different in different bodies4 ,hence1 on purpose to oxygenate most bodies1 especially the greater part of the simple substances1 it is only necessary to expose them to the influence of the air of the atmosphere in a convenient degree of temperature4 ,with respect to lead1 mercury1 and tin1 this needs be but little higher than the medium temperature of the earth2 but it requires a more considerable degree of heat to oxygenate iron1 copper1 c4 by the dry way1 or when this operation is not assisted by moisture4 ,sometimes oxygenation takes place with great rapidity1 and is accompanied by great sensible heat1 light1 and flame2 such is the combustion of phosphorus in atmospheric air1 and of iron in oxygen gas4 ,that of sulphur is less rapid2 and the oxygenation of lead1 tin1 and most of the metals1 takes place vastly slower1 and consequently the disengagement of caloric1 and more especially of light1 is hardly sensible4 ,some substances have so strong an affinity with oxygen1 and combine with it in such low degrees of temperature1 that we cannot procure them in their unoxygenated state2 such is the muriatic acid1 which has not hitherto been decomposed by art1 perhaps even not by nature1 and which consequently has only been found in the state of acid4 ,it is probable that many other substances of the mineral kingdom are necessarily oxygenated in the common temperature of the atmosphere1 and that being already saturated with oxygen1 prevents their farther action upon that element4 ,there are other means of oxygenating simple substances besides exposure to air in a certain degree of temperature1 such as by placing them in contact with metals combined with oxygen1 and which have little affinity with that element4 ,the red oxyd of mercury is one of the best substances for this purpose1 especially with bodies which do not combine with that metal4 ,in this oxyd the oxygen is united with very little force to the metal1 and can be driven out by a degree of heat only sufficient to make glass red hot2 wherefore such bodies as are capable of uniting with oxygen are readily oxygenated1 by means of being mixed with red oxyd of mercury1 and moderately heated4 ,the same effect may be1 to a certain degree1 produced by means of the black oxyd of manganese1 the red oxyd of lead1 the oxyds of silver1 and by most of the metallic oxyds1 if we only take care to choose such as have less affinity with oxygen than the bodies they are meant to oxygenate4 ,all the metallic reductions and revivifications belong to this class of operations1 being nothing more than oxygenations of charcoal1 by means of the several metallic oxyds4 ,the charcoal combines with the oxygen and with caloric1 and escapes in form of carbonic acid gas1 while the metal remains pure and revivified1 or deprived of the oxygen which before combined with it in the form of oxyd4 ,all combustible substances may likewise be oxygenated by means of mixing them with nitrat of potash or of soda1 or with oxygenated muriat of potash1 and subjecting the mixture to a certain degree of heat2 the oxygen1 in this case1 quits the nitrat or the muriat1 and combines with the combustible body4 ,this species of oxygenation requires to be performed with extreme caution1 and only with very small quantities2 because1 as the oxygen enters into the composition of nitrats1 and more especially of oxygenated muriats1 combined with almost as much caloric as is necessary for converting it into oxygen gas1 this immense quantity of caloric becomes suddenly free the instant of the combination of the oxygen with the combustible body1 and produces such violent explosions as are perfectly irresistible4 ,by the humid way we can oxygenate most combustible bodies1 and convert most of the oxyds of the three kingdoms of nature into acids4 ,for this purpose we chiefly employ the nitric acid1 which has a very slight hold of oxygen1 and quits it readily to a great number of bodies by the assistance of a gentle heat4 ,the oxygenated muriatic acid may be used for several operations of this kind1 but not in them all4 ,i give the name of binary to the combinations of oxygen with the simple substances1 because in these only two elements are combined4 ,when three substances are united in one combination ,i call it ternary1 and quaternary when the combination consists of four substances united4 ,,table of the combinations of ,oxygen with the compound radicals4 ,names of the radicals4 ,names of the resulting acids4 ,new nomenclature4 ,old nomenclature4 ,nitro muriatic ,nitro muriatic acid ,aqua regia4 radical 7,a7 ,tartaric ,tartarous acid ,unknown till lately4 ,malic ,malic acid ,ditto4 ,citric ,citric acid ,acid of lemons4 ,pyro-lignous ,pyro-lignous acid ,empyreumatic acid of wood4 ,pyro-mucous ,pyro-mucous acid ,empyr4 acid of sugar4 ,pyro-tartarous ,pyro-tartarous acid ,empyr4 acid of tartar4 ,oxalic ,oxalic acid ,acid of sorel4 ,acetic ,acetous acid ,vinegar1 or acid of vinegar4 ,acetic acid ,radical vinegar4 ,succinic ,succinic acid ,volatile salt of amber4 ,benzoic ,benzotic acid ,flowers of benzoin4 ,camphoric ,camphoric acid ,unknown till lately4 ,gallic ,gallic acid ,the astringent principle of vegetables4 7,b7 ,lactic ,lactic acid ,acid of sour whey4 ,saccholactic ,saccholactic acid ,unknown till lately4 ,formic ,formic acid ,acid of ants4 ,bombic ,bombic acid ,unknown till lately4 ,sebacic ,sebacic acid ,ditto4 ,lithic ,lithic acid ,urinary calculus4 ,prussic ,prussic acid ,colouring matter of ,prussian blue4 ,note ,a3 ,these radicals by a first degree of oxygenation form vegetable oxyds1 as sugar1 starch1 mucus1 c4--,a4 ,note ,b3 ,these radicals by a first degree of oxygenation form the animal oxyds1 as lymph1 red part of the blood1 animal secretions1 c4--,a4 ,,sect4 ,v4--,observations upon the ,combinations of ,oxygen with the ,compound ,radicals4 ,i published a new theory of the nature and formation of acids in the ,memoirs of the ,academy for #aggf1 p4 #fga4 and #aggh1 p4 #ece4 in which ,i concluded1 that the number of acids must be greatly larger than was till then supposed4 ,since that time1 a new field of inquiry has been opened to chemists2 and1 instead of five or six acids which were then known1 near thirty new acids have been discovered1 by which means the number of known neutral salts have been increased in the same proportion4 ,the nature of the acidifiable bases1 or radicals of the acids1 and the degrees of oxygenation they are susceptible of1 still remain to be inquired into4 ,i have already shown1 that almost all the oxydable and acidifiable radicals from the mineral kingdom are simple1 and that1 on the contrary1 there hardly exists any radical in the vegetable1 and more especially in the animal kingdom1 but is composed of at least two substances1 hydrogen and charcoal1 and that azote and phosphorus are frequently united to these1 by which we have compound radicals of two1 three1 and four bases or simple elements united4 ,from these observations1 it appears that the vegetable and animal oxyds and acids may differ from each other in three several ways3 #ast1 ,according to the number of simple acidifiable elements of which their radicals are composed3 #b;dly1 ,according to the proportions in which these are combined together3 ,and1 #c;dly1 ,according to their different degrees of oxygenation3 ,which circumstances are more than sufficient to explain the great variety which nature produces in these substances4 ,it is not at all surprising1 after this1 that most of the vegetable acids are convertible into each other1 nothing more being requisite than to change the proportions of the hydrogen and charcoal in their composition1 and to oxygenate them in a greater or lesser degree4 ,this has been done by ,mr ,crell in some very ingenious experiments1 which have been verified and extended by ,mr ,hassenfratz4 ,from these it appears1 that charcoal and hydrogen1 by a first oxygenation1 produce tartarous acid1 oxalic acid by a second degree1 and acetous or acetic acid by a third1 or higher oxygenation2 only1 that charcoal seems to exist in a rather smaller proportion in the acetous and acetic acids4 ,the citric and malic acids differ little from the preceding acids4 ,ought we then to conclude that the oils are the radicals of the vegetable and animal acids8 ,i have already expressed my doubts upon this subject3 #ast1 ,although the oils appear to be formed of nothing but hydrogen and charcoal1 we do not know if these are in the precise proportion necessary for constituting the radicals of the acids3 #b;dly1 ,since oxygen enters into the composition of these acids equally with hydrogen and charcoal1 there is no more reason for supposing them to be composed of oil rather than of water or of carbonic acid4 ,it is true that they contain the materials necessary for all these combinations1 but then these do not take place in the common temperature of the atmosphere2 all the three elements remain combined in a state of equilibrium1 which is readily destroyed by a temperature only a little above that of boiling water#ci4 ,,table of the ,binary ,combinations of ,azote with the ,simple ,substances4 ,simple ,substances4 ,results of the ,combinations4 ,new ,nomenclature4 ,old ,nomenclature4 ,caloric ,azotic gas ,phlogisticated air1 or ,mephitis4 ,hydrogen ,ammoniac ,volatile alkali4 ,nitrous oxyd ,base of ,nitrous gas4 ,nitrous acid ,smoaking nitrous acid4 ,oxygen ,nitric acid ,pale nitrous acid4 ,oxygenated nitric acid ,unknown4 ,this combination is hitherto unknown2 should it ever be discovered1 it will be called1 according to ,charcoal the principles of our nomenclature1 ,azuret of ,charcoal4 ,charcoal dissolves in azotic gas1 and forms carbonated azotic gas4 ,phosphorus4 ,azuret of phosphorus4 ,still unknown4 ,azuret of sulphur4 ,still unknown4 ,we know ,sulphur that sulphur dissolves in azotic gas1 forming sulphurated azotic gas4 ,azote combines with charcoal and hydrogen1 and ,compound sometimes with phosphorus1 in the compound radicals oxydable and acidifiable bases1 and is generally contained in the radicals of the animal acids4 ,such combinations are hitherto unknown2 if ever ,metallic discovered1 they will form metallic azurets1 as substances azuret of gold1 of silver1 c4 ,lime ,magnesia ,barytes ,entirely unknown4 ,if ever discovered1 they will ,argill form azuret of lime1 azuret of magnesia1 c4 ,potash ,soda ,,sect4 ,,vi4--,observations upon the ,combinations of ,azote with the ,simple ,substances4 ,azote is one of the most abundant elements2 combined with caloric it forms azotic gas1 or mephitis1 which composes nearly two thirds of the atmosphere4 ,this element is always in the state of gas in the ordinary pressure and temperature1 and no degree of compression or of cold has been hitherto capable of reducing it either to a solid or liquid form4 ,this is likewise one of the essential constituent elements of animal bodies1 in which it is combined with charcoal and hydrogen1 and sometimes with phosphorus2 these are united together by a certain portion of oxygen1 by which they are formed into oxyds or acids according to the degree of oxygenation4 ,hence the animal substances may be varied1 in the same way with vegetables1 in three different manners3 #ast1 ,according to the number of elements which enter into the composition of the base or radical3 #b;dly1 ,according to the proportions of these elements3 #c;dly1 ,according to the degree of oxygenation4 ,when combined with oxygen1 azote forms the nitrous and nitric oxyds and acids2 when with hydrogen1 ammoniac is produced4 ,its combinations with the other simple elements are very little known2 to these we give the name of ,azurets1 preserving the termination in uret for all nonoxygenated compounds4 ,it is extremely probable that all the alkaline substances may hereafter be found to belong to this genus of azurets4 ,the azotic gas may be procured from atmospheric air1 by absorbing the oxygen gas which is mixed with it by means of a solution of sulphuret of potash1 or sulphuret of lime4 ,it requires twelve or fifteen days to complete this process1 during which time the surface in contact must be frequently renewed by agitation1 and by breaking the pellicle which forms on the top of the solution4 ,it may likewise be procured by dissolving animal substances in dilute nitric acid very little heated4 ,in this operation1 the azote is disengaged in form of gas1 which we receive under bell glasses filled with water in the pneumato-chemical apparatus4 ,we may procure this gas by deflagrating nitre with charcoal1 or any other combustible substance2 when with charcoal1 the azotic gas is mixed with carbonic acid gas1 which may be absorbed by a solution of caustic alkali1 or by lime water1 after which the azotic gas remains pure4 ,we can procure it in a fourth manner from combinations of ammoniac with metallic oxyds1 as pointed out by ,mr de ,fourcroy3 ,the hydrogen of the ammoniac combines with the oxygen of the oxyd1 and forms water1 whilst the azote being left free escapes in form of gas4 ,the combinations of azote were but lately discovered3 ,mr ,cavendish first observed it in nitrous gas and acid1 and ,mr ,berthollet in ammoniac and the prussic acid4 ,as no evidence of its decomposition has hitherto appeared1 we are fully entitled to consider azote as a simple elementary substance4 ,,table of the ,binary ,combinations of ,hydrogen with ,simple ,substances4 ,simple ,resulting ,compounds4 ,substances4 ,new ,nomenclature4 ,old ,names4 ,caloric ,hydrogen gas ,inflammable air4 ,azote ,ammoniac ,volatile ,alkali4 ,oxygen ,water ,water4 ,sulphur ,hydruret of sulphur1 or sulphuret of hydrogen ,hitherto unknown 7,a74 ,phosphorus ,hydruret of phosphorus1 or phosphuret of hydrogen ,charcoal ,hydro-carbonous1 or ,not known till lately4 carbono-hydrous radicals7,b7 ,metallic ,metallic hydrurets7,c71 as ,hitherto unknown4 substances1 hydruret of iron1 c4 as iron1 c4 ,note ,a3 ,these combinations take place in the state of gas1 and form1 respectively1 sulphurated and phosphorated oxygen gas--,a4 ,note ,b3 ,this combination of hydrogen with charcoal includes the fixed and volatile oils1 and forms the radicals of a considerable part of the vegetable and animal oxyds and acids4 ,when it takes place in the state of gas it forms carbonated hydrogen gas4--,a4 ,note ,c3 ,none of these combinations are known1 and it is probable that they cannot exist1 at least in the usual temperature of the atmosphere1 owing to the great affinity of hydrogen for caloric4--,a4 ,,sect4 ,,vii4--,observations upon ,hydrogen1 and its ,combinations with ,simple ,substances4 ,hydrogen1 as its name expresses1 is one of the constituent elements of water1 of which it forms fifteen hundredth parts by weight1 combined with eighty-five hundredth parts of oxygen4 ,this substance1 the properties and even existence of which was unknown till lately1 is very plentifully distributed in nature1 and acts a very considerable part in the processes of the animal and vegetable kingdoms4 ,as it possesses so great affinity with caloric as only to exist in the state of gas1 it is consequently impossible to procure it in the concrete or liquid state1 independent of combination4 ,to procure hydrogen1 or rather hydrogen gas1 we have only to subject water to the action of a substance with which oxygen has greater affinity than it has to hydrogen2 by this means the hydrogen is set free1 and1 by uniting with caloric1 assumes the form of hydrogen gas4 ,red hot iron is usually employed for this purpose3 ,the iron1 during the process1 becomes oxydated1 and is changed into a substance resembling the iron ore from the island of ,elba4 ,in this state of oxyd it is much less attractible by the magnet1 and dissolves in acids without effervescence4 ,charcoal1 in a red heat1 has the same power of decomposing water1 by attracting the oxygen from its combination with hydrogen4 ,in this process carbonic acid gas is formed1 and mixes with the hydrogen gas1 but is easily separated by means of water or alkalies1 which absorb the carbonic acid1 and leave the hydrogen gas pure4 ,we may likewise obtain hydrogen gas by dissolving iron or zinc in dilute sulphuric acid4 ,these two metals decompose water very slowly1 and with great difficulty1 when alone1 but do it with great ease and rapidity when assisted by sulphuric acid2 the hydrogen unites with caloric during the process1 and is disengaged in form of hydrogen gas1 while the oxygen of the water unites with the metal in the form of oxyd1 which is immediately dissolved in the acid1 forming a sulphat of iron or of zinc4 ,some very distinguished chemists consider hydrogen as the phlogiston of ,stahl2 and as that celebrated chemist admitted the existence of phlogiston in sulphur1 charcoal1 metals1 c4 they are of course obliged to suppose that hydrogen exists in all these substances1 though they cannot prove their supposition2 even if they could1 it would not avail much1 since this disengagement of hydrogen is quite insufficient to explain the phenomena of calcination and combustion4 ,we must always recur to the examination of this question1 ,are the heat and light1 which are disengaged during the different species of combustion1 furnished by the burning body1 or by the oxygen which combines in all these operations8 ,and certainly the supposition of hydrogen being disengaged throws no light whatever upon this question4 ,besides1 it belongs to those who make suppositions to prove them2 and1 doubtless1 a doctrine which without any supposition explains the phenomena as well1 and as naturally1 as theirs does by supposition1 has at least the advantage of greater simplicity#dj4 ,,table of the ,binary ,combinations of ,sulphur with ,simple ,substances4 ,simple ,resulting ,compounds4 ,substances4 ,new ,nomenclature4 ,old ,nomenclature4 ,caloric ,sulphuric gas ,oxyd of sulphur ,soft sulphur4 ,oxygen ,sulphurous acid ,sulphureous acid4 ,sulphuric acid ,vitriolic acid4 ,hydrogen ,sulphuret of hydrogen ,azote azote ,unknown ,combinations4 ,phosphorus phosphorus ,charcoal charcoal ,antimony antimony ,crude antimony4 ,silver silver ,arsenic arsenic ,orpiment1 realgar4 ,bismuth bismuth ,cobalt cobalt ,copper copper ,copper pyrites4 ,tin tin ,iron iron ,iron pyrites4 ,manganese manganese ,mercury mercury ,ethiops mineral1 cinnabar4 ,molybdena molybdena ,nickel nickel ,gold gold ,platina platina ,lead lead ,galena4 ,tungstein tungstein ,zinc zinc ,blende4 ,alkaline liver of sulphur ,potash potash with fixed vegetable alkali4 ,alkaline liver of sulphur ,soda soda with fixed mineral alkali4 ,volatile liver of sulphur1 ,ammoniac ammoniac smoaking liquor of ,boyle4 ,lime lime ,calcareous liver of sulphur4 ,magnesia magnesia ,magnesian liver of sulphur4 ,barytes barytes ,barytic liver of sulphur4 ,argill argill ,yet unknown4 ,,sect4 ,,viii4--,observations on ,sulphur1 and its ,combinations4 ,sulphur is a combustible substance1 having a very great tendency to combination2 it is naturally in a solid state in the ordinary temperature1 and requires a heat somewhat higher than boiling water to make it liquify4 ,sulphur is formed by nature in a considerable degree of purity in the neighbourhood of volcanos2 we find it likewise1 chiefly in the state of sulphuric acid1 combined with argill in aluminous schistus1 with lime in gypsum1 c4 ,from these combinations it may be procured in the state of sulphur1 by carrying off its oxygen by means of charcoal in a red heat2 carbonic acid is formed1 and escapes in the state of gas2 the sulphur remains combined with the clay1 lime1 c4 in the state of sulphuret1 which is decomposed by acids2 the acid unites with the earth into a neutral salt1 and the sulphur is precipitated4 ,,table of the ,binary ,combinations of ,phosphorus with the ,simple ,substances4 ,simple ,substances4 ,resulting ,compounds4 ,caloric ,phosphoric gas4 ,oxyd of phosphorus4 ,oxygen ,phosphorous acid4 ,phosphoric acid4 ,hydrogen ,phosphuret of hydrogen4 ,azote ,phosphuret of azote4 ,sulphur ,phosphuret of ,sulphur4 ,charcoal ,phosphuret of charcoal4 ,metallic substances ,phosphuret of metals7,a74 ,potash ,soda ,ammoniac ,phosphuret of ,potash1 ,lime ,soda1 c47,b7 ,barytes ,magnesia ,argill ,note ,a3 ,of all these combinations of phosphorus with metals1 that with iron only is hitherto known1 forming the substance formerly called ,siderite2 neither is it yet ascertained whether1 in this combination1 the phosphorus be oxygenated or not4--,a4 ,note ,b3 ,these combinations of phosphorus with the alkalies and earths are not yet known2 and1 from the experiments of ,mr ,gengembre1 they appear to be impossible--,a4 ,,sect4 ,,ix4--,observations upon ,phosphorus1 and its ,combinations4 ,phosphorus is a simple combustible substance1 which was unknown to chemists till #affg1 when it was discovered by ,brandt1 who kept the process secret2 soon after ,kunkel found out ,brandt's method of preparation1 and made it public4 ,it has been ever since known by the name of ,kunkel's phosphorus4 ,it was for a long time procured only from urine2 and1 though ,homberg gave an account of the process in the ,memoirs of the ,academy for #afib1 all the philosophers of ,europe were supplied with it from ,england4 ,it was first made in ,france in #agcg1 before a committee of the ,academy at the ,royal ,garden4 ,at present it is procured in a more commodious and more oeconomical manner from animal bones1 which are real calcareous phosphats1 according to the process of ,messrs ,gahn1 ,scheele1 ,rouelle1 c4 ,the bones of adult animals being calcined to whiteness1 are pounded1 and passed through a fine silk sieve2 pour upon the fine powder a quantity of dilute sulphuric acid1 less than is sufficient for dissolving the whole4 ,this acid unites with the calcareous earth of the bones into a sulphat of lime1 and the phosphoric acid remains free in the liquor4 ,the liquid is decanted off1 and the residuum washed with boiling water2 this water which has been used to wash out the adhering acid is joined with what was before decanted off1 and the whole is gradually evaporated2 the dissolved sulphat of lime cristallizes in form of silky threads1 which are removed1 and by continuing the evaporation we procure the phosphoric acid under the appearance of a white pellucid glass4 ,when this is powdered1 and mixed with one third its weight of charcoal1 we procure very pure phosphorus by sublimation4 ,the phosphoric acid1 as procured by the above process1 is never so pure as that obtained by oxygenating pure phosphorus either by combustion or by means of nitric acid2 wherefore this latter should always be employed in experiments of research4 ,phosphorus is found in almost all animal substances1 and in some plants which give a kind of animal analysis4 ,in all these it is usually combined with charcoal1 hydrogen1 and azote1 forming very compound radicals1 which are1 for the most part1 in the state of oxyds by a first degree of union with oxygen4 ,the discovery of ,mr ,hassenfratz1 of phosphorus being contained in charcoal1 gives reason to suspect that it is more common in the vegetable kingdom than has generally been supposed3 ,it is certain1 that1 by proper processes1 it may be procured from every individual of some of the families of plants4 ,as no experiment has hitherto given reason to suspect that phosphorus is a compound body1 ,i have arranged it with the simple or elementary substances4 ,it takes fire at the temperature of #cb 7#ajd7 of the thermometer4 ,,table of the ,binary ,combinations of ,charcoal4 ,simple ,substances4 ,resulting ,compounds4 ,oxyd of charcoal ,unknown4 ,oxygen ,carbonic acid ,fixed air1 chalky acid4 ,sulphur ,carburet of sulphur ,phosphorus ,carburet of phosphorus ,unknown4 ,azote ,carburet of azote ,carbono-hydrous radical ,hydrogen ,fixed and volatile oils ,of these only the carburets of ,metallic substances ,carburets of metals iron and zinc are known1 and were formerly called ,plumbago4 ,alkalies and earths ,carburet of potash1 c4 ,unknown4 ,,sect4 ,x4--,observations upon ,charcoal1 and its ,combinations with ,simple ,substances4 ,as charcoal has not been hitherto decomposed1 it must1 in the present state of our knowledge1 be considered as a simple substance4 ,by modern experiments it appears to exist ready formed in vegetables2 and ,i have already remarked1 that1 in these1 it is combined with hydrogen1 sometimes with azote and phosphorus1 forming compound radicals1 which may be changed into oxyds or acids according to their degree of oxygenation4 ,to obtain the charcoal contained in vegetable or animal substances1 we subject them to the action of fire1 at first moderate1 and afterwards very strong1 on purpose to drive off the last portions of water1 which adhere very obstinately to the charcoal4 ,for chemical purposes1 this is usually done in retorts of stone-ware or porcellain1 into which the wood1 or other matter1 is introduced1 and then placed in a reverberatory furnace1 raised gradually to its greatest heat3 ,the heat volatilizes1 or changes into gas1 all the parts of the body susceptible of combining with caloric into that form1 and the charcoal1 being more fixed in its nature1 remains in the retort combined with a little earth and some fixed salts4 ,in the business of charring wood1 this is done by a less expensive process4 ,the wood is disposed in heaps1 and covered with earth1 so as to prevent the access of any more air than is absolutely necessary for supporting the fire1 which is kept up till all the water and oil is driven off1 after which the fire is extinguished by shutting up all the air-holes4 ,we may analyse charcoal either by combustion in air1 or rather in oxygen gas1 or by means of nitric acid4 ,in either case we convert it into carbonic acid1 and sometimes a little potash and some neutral salts remain4 ,this analysis has hitherto been but little attended to by chemists2 and we are not even certain if potash exists in charcoal before combustion1 or whether it be formed by means of some unknown combination during that process4 ,,sect4 ,,xi4--,observations upon the ,muriatic1 ,fluoric1 and ,boracic ,radicals1 and their ,combinations4 ,as the combinations of these substances1 either with each other1 or with the other combustible bodies1 are hitherto entirely unknown1 we have not attempted to form any table for their nomenclature4 ,we only know that these radicals are susceptible of oxygenation1 and of forming the muriatic1 fluoric1 and boracic acids1 and that in the acid state they enter into a number of combinations1 to be afterwards detailed4 ,chemistry has hitherto been unable to disoxygenate any of them1 so as to produce them in a simple state4 ,for this purpose1 some substance must be employed to which oxygen has a stronger affinity than to their radicals1 either by means of single affinity1 or by double elective attraction4 ,all that is known relative to the origin of the radicals of these acids will be mentioned in the sections set apart for considering their combinations with the salifiable bases4 ,,sect4 ,,xii4--,observations upon the ,combinations of ,metals with each other4 ,before closing our account of the simple or elementary substances1 it might be supposed necessary to give a table of alloys or combinations of metals with each other2 but1 as such a table would be both exceedingly voluminous and very unsatisfactory1 without going into a series of experiments not yet attempted1 ,i have thought it adviseable to omit it altogether4 ,all that is necessary to be mentioned is1 that these alloys should be named according to the metal in largest proportion in the mixture or combination2 thus the term alloy of gold and silver1 or gold alloyed with silver1 indicates that gold is the predominating metal4 ,metallic alloys1 like all other combinations1 have a point of saturation4 ,it would even appear1 from the experiments of ,mr de la ,briche1 that they have two perfectly distinct degrees of saturation4 ,,table of the ,combinations of ,azote in the state of ,nitrous ,acid with the ,salifiable ,bases1 arranged according to the affinities of these ,bases with the ,acid4 ,names of the bases4 ,names of the neutral salts4 ,new nomenclature4 ,notes4 ,barytes ,nitrite of barytes4 ,potash potash4 ,these salts are only ,soda soda4 known of late1 and ,lime lime4 have received no particular ,magnesia magnesia4 name in the old ,ammoniac ammoniac4 nomenclature4 ,argill argill4 ,as metals dissolve both in nitrous and ,oxyd of zinc zinc4 nitric acids1 metallic salts must of iron iron4 consequence be formed having manganese manganese4 different degrees of oxygenation4 cobalt cobalt4 ,those wherein the metal is nickel nickel4 least oxygenated must be lead lead4 called ,nitrites1 when more so1 tin tin4 ,nitrats2 but the limits of this copper copper4 distinction are difficultly bismuth bismuth4 ascertainable4 ,the older antimony antimony4 chemists were not acquainted arsenic arsenic4 with any of these salts4 mercury mercury4 silver ,it is extremely probable that gold1 silver gold and platina only form nitrats1 and cannot subsist platina in the state of nitrites4 ,,table of the ,combinations of ,azote1 completely saturated with ,oxygen1 in the state of ,nitric ,acid1 with the ,salifiable ,bases1 in the order of the affinity with the ,acid4 ,bases4 ,names of the resulting neutral salts4 ,new nomenclature4 ,old nomenclature4 ,barytes ,nitrat of barytes ,nitre1 with a base of heavy earth4 ,potash potash ,nitre1 saltpetre4 ,nitre with base of potash4 ,soda soda ,quadrangular nitre4 ,nitre with base of mineral alkali4 ,calcareous nitre4 ,nitre with ,lime lime calcareous base4 ,mother water of nitre1 or saltpetre4 ,magnesia magnesia ,magnesian nitre4 ,nitre with base of magnesia4 ,ammoniac ammoniac ,ammoniacal nitre4 ,nitrous alum4 ,argillaceous nitre4 ,nitre ,argill argill with base of earth of alum4 ,oxyd of zinc zinc ,nitre of zinc4 iron iron ,nitre of iron4 ,martial nitre4 ,nitrated iron4 manganese manganese ,nitre of manganese4 cobalt cobalt ,nitre of cobalt4 nickel nickel ,nitre of nickel4 lead lead ,saturnine nitre4 ,nitre of lead4 tin tin ,nitre of tin4 copper copper ,nitre of copper or of ,venus4 bismuth bismuth ,nitre of bismuth4 antimony antimony ,nitre of antimony4 arsenic arsenic ,arsenical nitre4 mercury mercury ,mercurial nitre4 silver silver ,nitre of silver or luna4 ,lunar caustic4 gold gold ,nitre of gold4 platina platina ,nitre of platina4 ,,sect4 ,,xiii4--,observations upon the ,nitrous and ,nitric ,acids1 and their ,combinations4 ,the nitrous and nitric acids are procured from a neutral salt long known in the arts under the name of saltpetre4 ,this salt is extracted by lixiviation from the rubbish of old buildings1 from the earth of cellars1 stables1 or barns1 and in general of all inhabited places4 ,in these earths the nitric acid is usually combined with lime and magnesia1 sometimes with potash1 and rarely with argill4 ,as all these salts1 excepting the nitrat of potash1 attract the moisture of the air1 and consequently would be difficultly preserved1 advantage is taken1 in the manufactures of saltpetre and the royal refining house1 of the greater affinity of the nitric acid to potash than these other bases1 by which means the lime1 magnesia1 and argill1 are precipitated1 and all these nitrats are reduced to the nitrat of potash or saltpetre#da4 ,the nitric acid is procured from this salt by distillation1 from three parts of pure saltpetre decomposed by one part of concentrated sulphuric acid1 in a retort with ,woulfe's apparatus1 7,pl4 ,,iv4 fig4 #a47 having its bottles half filled with water1 and all its joints carefully luted4 ,the nitrous acid passes over in form of red vapours surcharged with nitrous gas1 or1 in other words1 not saturated with oxygen4 ,part of the acid condenses in the recipient in form of a dark orange red liquid1 while the rest combines with the water in the bottles4 ,during the distillation1 a large quantity of oxygen gas escapes1 owing to the greater affinity of oxygen to caloric1 in a high temperature1 than to nitrous acid1 though in the usual temperature of the atmosphere this affinity is reversed4 ,it is from the disengagement of oxygen that the nitric acid of the neutral salt is in this operation converted into nitrous acid4 ,it is brought back to the state of nitric acid by heating over a gentle fire1 which drives off the superabundant nitrous gas1 and leaves the nitric acid much diluted with water4 ,nitric acid is procurable in a more concentrated state1 and with much less loss1 by mixing very dry clay with saltpetre4 ,this mixture is put into an earthern retort1 and distilled with a strong fire4 ,the clay combines with the potash1 for which it has great affinity1 and the nitric acid passes over1 slightly impregnated with nitrous gas4 ,this is easily disengaged by heating the acid gently in a retort1 a small quantity of nitrous gas passes over into the recipient1 and very pure concentrated nitric acid remains in the retort4 ,we have already seen that azote is the nitric radical4 ,if to #bj-a_/b parts1 by weight1 of azote #dc-a_/b parts of oxygen be added1 #fd parts of nitrous gas are formed2 and1 if to this we join #cf additional parts of oxygen1 #ajj parts of nitric acid result from the combination4 ,intermediate quantities of oxygen between these two extremes of oxygenation produce different species of nitrous acid1 or1 in other words1 nitric acid less or more impregnated with nitrous gas4 ,i ascertained the above proportions by means of decomposition2 and1 though ,i cannot answer for their absolute accuracy1 they cannot be far removed from truth4 ,mr ,cavendish1 who first showed by synthetic experiments that azote is the base of nitric acid1 gives the proportions of azote a little larger than ,i have done2 but1 as it is not improbable that he produced the nitrous acid and not the nitric1 that circumstance explains in some degree the difference in the results of our experiments4 ,as1 in all experiments of a philosophical nature1 the utmost possible degree of accuracy is required1 we must procure the nitric acid for experimental purposes1 from nitre which has been previously purified from all foreign matter4 ,if1 after distillation1 any sulphuric acid is suspected in the nitric acid1 it is easily separated by dropping in a little nitrat of barytes1 so long as any precipitation takes place2 the sulphuric acid1 from its greater affinity1 attracts the barytes1 and forms with it an insoluble neutral salt1 which falls to the bottom4 ,it may be purified in the same manner from muriatic acid1 by dropping in a little nitrat of silver so long as any precipitation of muriat of silver is produced4 ,when these two precipitations are finished1 distill off about seven-eighths of the acid by a gentle heat1 and what comes over is in the most perfect degree of purity4 ,the nitric acid is one of the most prone to combination1 and is at the same time very easily decomposed4 ,almost all the simple substances1 with the exception of gold1 silver1 and platina1 rob it less or more of its oxygen2 some of them even decompose it altogether4 ,it was very anciently known1 and its combinations have been more studied by chemists than those of any other acid4 ,these combinations were named nitres by ,messrs ,macquer and ,beaum2 but we have changed their names to nitrats and nitrites1 according as they are formed by nitric or by nitrous acid1 and have added the specific name of each particular base1 to distinguish the several combinations from each other4 ,,table of the ,combinations of ,sulphuric ,acid with the ,salifiable ,bases1 in the order of affinity4 ,names of the bases4 ,resulting compounds4 ,new nomenclature4 ,old nomenclature4 ,barytes ,sulphat of barytes ,heavy spar4 ,vitriol of heavy earth4 ,potash potash ,vitriolated tartar4 ,sal de duobus4 ,arcanum duplicatam4 ,soda soda ,glauber's salt4 ,lime lime ,selenite1 gypsum1 calcareous vitriol4 ,magnesia magnesia ,epsom salt1 sedlitz salt1 magnesian vitriol4 ,ammoniac ammoniac ,glauber's secret sal ammoniac4 ,argill argill ,alum4 ,oxyd of zinc zinc ,white vitriol1 goslar vitriol1 white coperas1 vitriol of zinc4 iron iron ,green coperas1 green vitriol1 martial vitriol1 vitriol of iron4 manganese manganese ,vitriol of manganese4 cobalt cobalt ,vitriol of cobalt4 nickel nickel ,vitriol of nickel4 lead lead ,vitriol of lead4 tin tin ,vitriol of tin4 copper copper ,blue coperas1 blue vitriol1 ,roman vitriol1 vitriol of copper4 bismuth bismuth ,vitriol of bismuth4 antimony antimony ,vitriol of antimony4 arsenic arsenic ,vitriol of arsenic4 mercury mercury ,vitriol of mercury4 silver silver ,vitriol of silver4 gold gold ,vitriol of gold4 platina platina ,vitriol of platina4 ,,sect4 ,,xiv4--,observations upon ,sulphuric ,acid and its ,combinations4 ,for a long time this acid was procured by distillation from sulphat of iron1 in which sulphuric acid and oxyd of iron are combined1 according to the process described by ,basil ,valentine in the fifteenth century2 but1 in modern times1 it is procured more oeconomically by the combustion of sulphur in proper vessels4 ,both to facilitate the combustion1 and to assist the oxygenation of the sulphur1 a little powdered saltpetre1 nitrat of potash1 is mixed with it2 the nitre is decomposed1 and gives out its oxygen to the sulphur1 which contributes to its conversion into acid4 ,notwithstanding this addition1 the sulphur will only continue to burn in close vessels for a limited time2 the combination ceases1 because the oxygen is exhausted1 and the air of the vessels reduced almost to pure azotic gas1 and because the acid itself remains long in the state of vapour1 and hinders the progress of combustion4 ,in the manufactories for making sulphuric acid in the large way1 the mixture of nitre and sulphur is burnt in large close built chambers lined with lead1 having a little water at the bottom for facilitating the condensation of the vapours4 ,afterwards1 by distillation in large retorts with a gentle heat1 the water passes over1 slightly impregnated with acid1 and the sulphuric acid remains behind in a concentrated state4 ,it is then pellucid1 without any flavour1 and nearly double the weight of an equal bulk of water4 ,this process would be greatly facilitated1 and the combustion much prolonged1 by introducing fresh air into the chambers1 by means of several pairs of bellows directed towards the flame of the sulphur1 and by allowing the nitrous gas to escape through long serpentine canals1 in contact with water1 to absorb any sulphuric or sulphurous acid gas it might contain4 ,by one experiment1 ,mr ,berthollet found that #fi parts of sulphur in combustion1 united with #ca parts of oxygen1 to form #ajj parts of sulphuric acid2 and1 by another experiment1 made in a different manner1 he calculates that #ajj parts of sulphuric acid consists of #gb parts sulphur1 combined with #bh parts of oxygen1 all by weight4 ,this acid1 in common with every other1 can only dissolve metals when they have been previously oxydated2 but most of the metals are capable of decomposing a part of the acid1 so as to carry off a sufficient quantity of oxygen1 to render themselves soluble in the part of the acid which remains undecomposed4 ,this happens with silver1 mercury1 iron1 and zinc1 in boiling concentrated sulphuric acid2 they become first oxydated by decomposing part of the acid1 and then dissolve in the other part2 but they do not sufficiently disoxygenate the decomposed part of the acid to reconvert it into sulphur2 it is only reduced to the state of sulphurous acid1 which1 being volatilised by the heat1 flies off in form of sulphurous acid gas4 ,silver1 mercury1 and all the other metals except iron and zinc1 are insoluble in diluted sulphuric acid1 because they have not sufficient affinity with oxygen to draw it off from its combination either with the sulphur1 the sulphurous acid1 or the hydrogen2 but iron and zinc1 being assisted by the action of the acid1 decompose the water1 and become oxydated at its expence1 without the help of heat4 ,,table of the ,combinations of the ,sulphurous ,acid with the ,salifiable ,bases1 in the order of affinity4 ,names of the ,bases4 ,names of the ,neutral ,salts4 ,barytes ,sulphite of barytes4 ,potash potash4 ,soda soda4 ,lime lime4 ,magnesia magnesia4 ,ammoniac ammoniac4 ,argill argill4 ,oxyd of zinc zinc4 iron iron4 manganese manganese4 cobalt cobalt4 nickel nickel4 lead lead4 tin tin4 copper copper4 bismuth bismuth4 antimony antimony4 arsenic arsenic4 mercury mercury4 silver silver4 gold gold4 platina platina4 ,note4--,the only one of these salts known to the old chemists was the sulphite of potash1 under the name of ,stahl's sulphureous salt4 ,so that1 before our new nomenclature1 these compounds must have been named ,stahl's sulphureous salt1 having base of fixed vegetable alkali1 and so of the rest4 ,in this ,table we have followed ,bergman's order of affinity of the sulphuric acid1 which is the same in regard to the earths and alkalies1 but it is not certain if the order be the same for the metallic oxyds4--,a4 ,,sect4 ,,xv4--,observations upon ,sulphurous ,acid1 and its ,combinations4 ,the sulphurous acid is formed by the union of oxygen with sulphur by a lesser degree of oxygenation than the sulphuric acid4 ,it is procurable either by burning sulphur slowly1 or by distilling sulphuric acid from silver1 antimony1 lead1 mercury1 or charcoal2 by which operation a part of the oxygen quits the acid1 and unites to these oxydable bases1 and the acid passes over in the sulphurous state of oxygenation4 ,this acid1 in the common pressure and temperature of the air1 can only exist in form of gas2 but it appears1 from the experiments of ,mr ,clouet1 that1 in a very low temperature1 it condenses1 and becomes fluid4 ,water absorbs a great deal more of this gas than of carbonic acid gas1 but much less than it does of muriatic acid gas4 ,that the metals cannot be dissolved in acids without being previously oxydated1 or by procuring oxygen1 for that purpose1 from the acids during solution1 is a general and well established fact1 which ,i have perhaps repeated too often4 ,hence1 as sulphurous acid is already deprived of great part of the oxygen necessary for forming the sulphuric acid1 it is more disposed to recover oxygen1 than to furnish it to the greatest part of the metals2 and1 for this reason1 it cannot dissolve them1 unless previously oxydated by other means4 ,from the same principle it is that the metallic oxyds dissolve without effervescence1 and with great facility1 in sulphurous acid4 ,this acid1 like the muriatic1 has even the property of dissolving metallic oxyds surcharged with oxygen1 and consequently insoluble in sulphuric acid1 and in this way forms true sulphats4 ,hence we might be led to conclude that there are no metallic sulphites1 were it not that the phenomena which accompany the solution of iron1 mercury1 and some other metals1 convince us that these metallic substances are susceptible of two degrees of oxydation1 during their solution in acids4 ,hence the neutral salt in which the metal is least oxydated must be named sulphite1 and that in which it is fully oxydated must be called sulphat4 ,it is yet unknown whether this distinction is applicable to any of the metallic sulphats1 except those of iron and mercury4 ,,table of the ,combinations of ,phosphorous and ,phosphoric ,acids1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,names of the ,names of the ,neutral ,salts formed by ,bases4 ,phosphorous ,acid1 ,phosphoric ,acid4 ,phosphites of7,b7 ,phosphats of7,c7 ,lime lime lime4 ,barytes barytes barytes4 ,magnesia magnesia magnesia4 ,potash potash potash4 ,soda soda soda4 ,ammoniac ammoniac ammoniac4 ,argill argill argill4 ,oxyds of7,a7 zinc zinc zinc4 iron iron iron4 manganese manganese manganese4 cobalt cobalt cobalt4 nickel nickel nickel4 lead lead lead4 tin tin tin4 copper copper copper4 bismuth bismuth bismuth4 antimony antimony antimony4 arsenic arsenic arsenic4 mercury mercury mercury4 silver silver silver4 gold gold gold4 platina platina platina4 ,note ,a3 ,the existence of metallic phosphites supposes that metals are susceptible of solution in phosphoric acid at different degrees of oxygenation1 which is not yet ascertained4--,a4 ,note ,b3 ,all the phosphites were unknown till lately1 and consequently have not hitherto received names4--,a4 ,note ,c3 ,the greater part of the phosphats were only discovered of late1 and have not yet been named4--,a4 ,,sect4 ,,xvi4--,observations upon ,phosphorous and ,phosphoric ,acids1 and their ,combinations4 ,under the article ,phosphorus1 ,part ,,ii4 ,sect4 ,x4 we have already given a history of the discovery of that singular substance1 with some observations upon the mode of its existence in vegetable and animal bodies4 ,the best method of obtaining this acid in a state of purity is by burning well purified phosphorus under bell-glasses1 moistened on the inside with distilled water2 during combustion it absorbs twice and a half its weight of oxygen2 so that #ajj parts of phosphoric acid is composed of #bh-a_/b parts of phosphorus united to #ga-a_/b parts of oxygen4 ,this acid may be obtained concrete1 in form of white flakes1 which greedily attract the moisture of the air1 by burning phosphorus in a dry glass over mercury4 ,to obtain phosphorous acid1 which is phosphorus less oxygenated than in the state of phosphoric acid1 the phosphorus must be burnt by a very slow spontaneous combustion over a glass-funnel leading into a crystal phial2 after a few days1 the phosphorus is found oxygenated1 and the phosphorous acid1 in proportion as it forms1 has attracted moisture from the air1 and dropped into the phial4 ,the phosphorous acid is readily changed into phosphoric acid by exposure for a long time to the free air2 it absorbs oxygen from the air1 and becomes fully oxygenated4 ,as phosphorus has a sufficient affinity for oxygen to attract it from the nitric and muriatic acids1 we may form phosphoric acid1 by means of these acids1 in a very simple and cheap manner4 ,fill a tubulated receiver1 half full of concentrated nitric acid1 and heat it gently1 then throw in small pieces of phosphorus through the tube1 these are dissolved with effervescence and red fumes of nitrous gas fly off2 add phosphorus so long as it will dissolve1 and then increase the fire under the retort to drive off the last particles of nitric acid2 phosphoric acid1 partly fluid and partly concrete1 remains in the retort4 ,,table of the ,combinations of ,carbonic ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,names of ,resulting ,neutral ,salts4 ,bases ,new ,nomenclature4 ,old ,nomenclature4 ,barytes ,carbonates of barytes7,a7 ,arated or effervescent heavy earth4 ,lime lime ,chalk1 calcareous spar1 ,arated calcareous earth4 ,potash potash ,effervescing or arated fixe vegetable alkali1 mephitis of potash4 ,soda soda ,arated or effervescing fixed mineral alkali1 mephitic soda4 ,magnesia magnesia ,arated1 effervescing1 mild1 or mephitic magnesia4 ,ammoniac ammoniac ,arated1 effervescing1 mild1 or mephitic volatile alkali4 ,argill argill ,arated or effervescing argillaceous earth1 or earth of alum4 ,oxyds of zinc zinc ,zinc spar1 mephitic or arated zinc4 iron iron ,sparry iron-ore1 mephitic or arated iron4 manganese manganese ,arated manganese4 cobalt cobalt ,arated cobalt4 nickel nickel ,arated nickel4 lead lead ,sparry lead-ore1 or arated lead4 tin tin ,arated tin4 copper copper ,arated copper4 bismuth bismuth ,arated bismuth4 antimony antimony ,arated antimony4 arsenic arsenic ,arated arsenic4 mercury mercury ,arated mercury4 silver silver ,arated silver4 gold gold ,arated gold4 platina platina ,arated platina4 ,note ,a3 ,as these salts have only been understood of late1 they have not1 properly speaking1 any old names4 ,mr ,morveau1 in the ,first ,volume of the ,encyclopedia1 calls them ,mephites2 ,mr ,bergman gives them the name of arated2 and ,mr de ,fourcroy1 who calls the carbonic acid chalky acid1 gives them the name of chalks4--,a ,,sect4 ,,xvii4--,observations upon ,carbonic ,acid1 and its ,combinations4 ,of all the known acids1 the carbonic is the most abundant in nature2 it exists ready formed in chalk1 marble1 and all the calcareous stones1 in which it is neutralized by a particular earth called lime4 ,to disengage it from this combination1 nothing more is requisite than to add some sulphuric acid1 or any other which has a stronger affinity for lime2 a brisk effervescence ensues1 which is produced by the disengagement of the carbonic acid which assumes the state of gas immediately upon being set free4 ,this gas1 incapable of being condensed into the solid or liquid form by any degree of cold or of pressure hitherto known1 unites to about its own bulk of water1 and thereby forms a very weak acid4 ,it may likewise be obtained in great abundance from saccharine matter in fermentation1 but is then contaminated by a small portion of alkohol which it holds in solution4 ,as charcoal is the radical of this acid1 we may form it artificially1 by burning charcoal in oxygen gas1 or by combining charcoal and metallic oxyds in proper proportions2 the oxygen of the oxyd combines with the charcoal1 forming carbonic acid gas1 and the metal being left free1 recovers its metallic or reguline form4 ,we are indebted for our first knowledge of this acid to ,dr ,black1 before whose time its property of remaining always in the state of gas had made it to elude the researches of chemistry4 ,it would be a most valuable discovery to society1 if we could decompose this gas by any cheap process1 as by that means we might obtain1 for economical purposes1 the immense store of charcoal contained in calcareous earths1 marbles1 limestones1 c4 ,this cannot be effected by single affinity1 because1 to decompose the carbonic acid1 it requires a substance as combustible as charcoal itself1 so that we should only make an exchange of one combustible body for another not more valuable2 but it may possibly be accomplished by double affinity1 since this process is so readily performed by ,nature1 during vegetation1 from the most common materials4 ,,table of the ,combinations of ,muriatic ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,names of the ,resulting ,neutral ,salts4 bases4 ,new nomenclature4 ,old nomenclature4 ,barytes4 ,muriat of ,sea-salt1 having base of barytes heavy earth4 ,potash potash ,febrifuge salt of ,sylvius3 ,muriated vegetable fixed alkali4 ,soda soda ,sea-salt4 ,lime lime ,muriated lime4 ,oil of lime4 ,magnesia magnesia ,marine ,epsom salt4 ,muriated magnesia4 ,ammoniac ammoniac ,sal ammoniac4 ,argill argill ,muriated alum1 sea-salt with base of earth of alum4 ,oxyd of zinc zinc ,sea-salt of1 or muriatic zinc4 iron iron ,salt of iron1 ,martial sea-salt4 manganese manganese ,sea-salt of manganese4 cobalt cobalt ,sea-salt of cobalt4 nickel nickel ,sea-salt of nickel4 lead lead ,horny-lead4 ,plumbum corneum4 tin smoaking of tin ,smoaking liquor of ,libavius4 solid of tin ,solid butter of tin4 copper copper ,sea-salt of copper4 bismuth bismuth ,sea-salt of bismuth4 antimony antimony ,sea-salt of antimony4 arsenic arsenic ,sea-salt of arsenic4 sweet of mercury ,sweet sublimate of mercury1 calomel1 aquila alba4 mercury corrosive of ,corrosive sublimate of mercury mercury4 silver silver ,horny silver1 argentum corneum1 luna cornea4 gold gold ,sea-salt of gold4 platina platina ,sea-salt of platina4 ,,table ,of the ,combinations of ,oxygenated ,muriatic ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,names of the ,neutral ,salts by ,names of the ,bases4 the new ,nomenclature4 ,oxygenated muriat of ,barytes barytes4 ,potash potash4 ,soda soda4 ,lime lime4 ,magnesia magnesia4 ,argill argill4 ,oxyd of zinc zinc4 iron iron4 manganese manganese4 cobalt cobalt4 nickel nickel4 lead lead4 tin tin4 copper copper4 bismuth bismuth4 antimony antimony4 arsenic arsenic4 mercury mercury4 silver silver4 gold gold4 platina platina4 ,this order of salts1 entirely unknown to the ancient chemists1 was discovered in #aghf by ,mr ,berthollet4--,a4 ,,sect4 ,,xix4--,observations upon ,muriatic and ,oxygenated ,muriatic ,acids1 and their ,combinations4 ,muriatic acid is very abundant in the mineral kingdom naturally combined with different salifiable bases1 especially with soda1 lime1 and magnesia4 ,in sea-water1 and the water of several lakes1 it is combined with these three bases1 and in mines of rock-salt it is chiefly united to soda4 ,this acid does not appear to have been hitherto decomposed in any chemical experiment2 so that we have no idea whatever of the nature of its radical1 and only conclude1 from analogy with the other acids1 that it contains oxygen as its acidifying principle4 ,mr ,berthollet suspects the radical to be of a metallic nature2 but1 as ,nature appears to form this acid daily1 in inhabited places1 by combining miasmata with ariform fluids1 this must necessarily suppose a metallic gas to exist in the atmosphere1 which is certainly not impossible1 but cannot be admitted without proof4 ,the muriatic acid has only a moderate adherence to the salifiable bases1 and can readily be driven from its combination with these by sulphuric acid4 ,other acids1 as the nitric1 for instance1 may answer the same purpose2 but nitric acid being volatile1 would mix1 during distillation1 with the muriatic4 ,about one part of sulphuric acid is sufficient to decompose two parts of decrepitated sea-salt4 ,this operation is performed in a tubulated retort1 having ,woulfe's apparatus1 7,pl4 ,,iv4 ,fig4 #a471 adapted to it4 ,when all the junctures are properly lured1 the sea-salt is put into the retort through the tube1 the sulphuric acid is poured on1 and the opening immediately closed with its ground crystal stopper4 ,as the muriatic acid can only subsist in the gaseous form in the ordinary temperature1 we could not condense it without the presence of water4 ,hence the use of the water with which the bottles in ,woulfe's apparatus are half filled2 the muriatic acid gas1 driven off from the sea-salt in the retort1 combines with the water1 and forms what the old chemists called smoaking spirit of salt1 or ,glauber's spirit of sea-salt1 which we now name muriatic acid4 ,the acid obtained by the above process is still capable of combining with a farther dose of oxygen1 by being distilled from the oxyds of manganese1 lead1 or mercury1 and the resulting acid1 which we name oxygenated muriatic acid1 can only1 like the former1 exist in the gasseous form1 and is absorbed1 in a much smaller quantity by water4 ,when the impregnation of water with this gas is pushed beyond a certain point1 the superabundant acid precipitates to the bottom of the vessels in a concrete form4 ,mr ,berthollet has shown that this acid is capable of combining with a great number of the salifiable bases2 the neutral salts which result from this union are susceptible of deflagrating with charcoal1 and many of the metallic substances2 these deflagrations are very violent and dangerous1 owing to the great quantity of caloric which the oxygen carries alongst with it into the composition of oxygenated muriatic acid4 ,,table of the ,combinations of ,nitro-muriatic ,acid with the ,salifiable ,bases1 in the ,order of ,affinity1 so far as is known4 ,names of the ,bases4 ,names of the ,neutral ,salts4 ,argill ,nitro-muriat of argill4 ,ammoniac ammoniac4 ,oxyd of antimony antimony4 silver silver4 arsenic arsenic4 ,barytes barytes4 ,oxyd of bismuth bismuth4 ,lime lime4 ,oxyd of cobalt cobalt4 copper copper4 tin tin4 iron iron4 ,magnesia magnesia4 ,oxyd of manganese manganese4 mercury mercury4 molybdena molybdena4 nickel nickel4 gold gold4 platina platina4 lead lead4 ,potash potash4 ,soda soda4 ,oxyd of tungstein tungstein4 zinc zinc4 ,note4--,most of these combinations1 especially those with the earths and alkalies1 have been little examined1 and we are yet to learn whether they form a mixed salt in which the compound radical remains combined1 or if the two acids separate1 to form two distinct neutral salts4--,a4 ,,sect4 ,,xx4--,observations upon the ,nitro-,muriatic ,acid1 and its ,combinations4 ,the nitro-muriatic acid1 formerly called aqua regia1 is formed by a mixture of nitric and muriatic acids2 the radicals of these two acids combine together1 and form a compound base1 from which an acid is produced1 having properties peculiar to itself1 and distinct from those of all other acids1 especially the property of dissolving gold and platina4 ,in dissolutions of metals in this acid1 as in all other acids1 the metals are first oxydated by attracting a part of the oxygen from the compound radical4 ,this occasions a disengagement of a particular species of gas not hitherto described1 which may be called nitro-muriatic gas2 it has a very disagreeable smell1 and is fatal to animal life when respired2 it attacks iron1 and causes it to rust2 it is absorbed in considerable quantity by water1 which thereby acquires some slight characters of acidity4 ,i had occasion to make these remarks during a course of experiments upon platina1 in which ,i dissolved a considerable quantity of that metal in nitro-muriatic acid4 ,i at first suspected that1 in the mixture of nitric and muriatic acids1 the latter attracted a part of the oxygen from the former1 and became converted into oxygenated muriatic acid1 which gave it the property of dissolving gold2 but several facts remain inexplicable upon this supposition4 ,were it so1 we must be able to disengage nitrous gas by heating this acid1 which however does not sensibly happen4 ,from these considerations1 ,i am led to adopt the opinion of ,mr ,berthollet1 and to consider nitro-muriatic acid as a single acid1 with a compound base or radical4 ,,table of the ,combinations of ,fluoric ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,names of the ,bases4 ,names of the ,neutral ,salts4 ,lime ,fluat of lime4 ,barytes barytes4 ,magnesia magnesia4 ,potash potash4 ,soda soda4 ,ammoniac ammoniac4 ,oxyd of zinc zinc4 manganese manganese4 iron iron4 lead lead4 tin tin4 cobalt cobalt4 copper copper4 nickel nickel4 arsenic arsenic4 bismuth bismuth4 mercury mercury4 silver silver4 gold gold4 platina platina4 ,and by the dry way1 ,argill ,fluat of argill4 ,note4--,these combinations were entirely unknown to the old chemists1 and consequently have no names in the old nomenclature4--,a4 ,,sect4 ,,xxi4--,observations upon the ,fluoric ,acid1 and its ,combinations4 ,fluoric exists ready formed by ,nature in the fluoric spars#db1 combined with calcareous earth1 so as to form an insoluble neutral salt4 ,to obtain it disengaged from that combination1 fluor spar1 or fluat of lime1 is put into a leaden retort1 with a proper quantity of sulphuric acid1 a recipient likewise of lead1 half full of water1 is adapted1 and fire is applied to the retort4 ,the sulphuric acid1 from its greater affinity1 expels the fluoric acid which passes over and is absorbed by the water in the receiver4 ,as fluoric acid is naturally in the gasseous form in the ordinary temperature1 we can receive it in a pneumato-chemical apparatus over mercury4 ,we are obliged to employ metallic vessels in this process1 because fluoric acid dissolves glass and silicious earth1 and even renders these bodies volatile1 carrying them over with itself in distillation in the gasseous form4 ,we are indebted to ,mr ,margraff for our first acquaintance with this acid1 though1 as he could never procure it free from combination with a considerable quantity of silicious earth1 he was ignorant of its being an acid sui generis4 ,the ,duke de ,liancourt1 under the name of ,mr ,boulanger1 considerably increased our knowledge of its properties2 and ,mr ,scheele seems to have exhausted the subject4 ,the only thing remaining is to endeavour to discover the nature of the fluoric radical1 of which we cannot hitherto form any ideas1 as the acid does not appear to have been decomposed in any experiment4 ,it is only by means of compound affinity that experiments ought to be made with this view1 with any probability of success4 ,,table of the ,combinations of ,boracic ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,bases4 ,neutral ,salts4 ,lime ,borat of lime4 ,barytes barytes4 ,magnesia magnesia4 ,potash potash4 ,soda soda4 ,ammoniac ammoniac4 ,oxyd of zinc zinc4 iron iron4 lead lead4 tin tin4 cobalt cobalt4 copper copper4 nickel nickel4 mercury mercury4 ,argill argill4 ,note4--,most of these combinations were neither known nor named by the old chemists4 ,the boracic acid was formerly called sedative salt1 and its compounds borax1 with base of fixed vegetable alkali1 c4--,a4 ,,sect4 ,,xxii4--,observations upon ,boracic ,add and its ,combinations4 ,this is a concrete acid1 extracted from a salt procured from ,india called borax or tincall4 ,although borax has been very long employed in the arts1 we have as yet very imperfect knowledge of its origin1 and of the methods by which it is extracted and purified2 there is reason to believe it to be a native salt1 found in the earth in certain parts of the east1 and in the water of some lakes4 ,the whole trade of borax is in the hands of the ,dutch1 who have been exclusively possessed of the art of purifying it till very lately1 that ,messrs ,l',eguillier of ,paris have rivalled them in the manufacture2 but the process still remains a secret to the world4 ,by chemical analysis we learn that borax is a neutral salt with excess of base1 consisting of soda1 partly saturated with a peculiar acid long called ,homberg's sedative salt1 now the boracic acid4 ,this acid is found in an uncombined state in the waters of certain lakes4 ,that of ,cherchiais in ,italy contains #id-a_/b grains in each pint of water4 ,to obtain boracic acid1 dissolve some borax in boiling water1 filtrate the solution1 and add sulphuric acid1 or any other having greater affinity to soda than the boracic acid2 this latter acid is separated1 and is procured in a crystalline form by cooling4 ,this acid was long considered as being formed during the process by which it is obtained1 and was consequently supposed to differ according to the nature of the acid employed in separating it from the soda2 but it is now universally acknowledged that it is identically the same acid1 in whatever way procured1 provided it be properly purified from mixture of other acids1 by warning1 and by repeated solution and cristallization4 ,it is soluble both in water and alkohol1 and has the property of communicating a green colour to the flame of that spirit4 ,this circumstance led to a suspicion of its containing copper1 which is not confirmed by any decisive experiment4 ,on the contrary1 if it contain any of that metal1 it must only be considered as an accidental mixture4 ,it combines with the salifiable bases in the humid way2 and though1 in this manner1 it is incapable of dissolving any of the metals directly1 this combination is readily affected by compound affinity4 ,the ,table presents its combinations in the order of affinity in the humid way2 but there is a considerable change in the order when we operate via sicca2 for1 in that case1 argill1 though the last in our list1 must be placed immediately after soda4 ,the boracic radical is hitherto unknown2 no experiments having as yet been able to decompose the acid2 ,we conclude1 from analogy with the other acids1 that oxygen exists in its composition as the acidifying principle4 ,,table of the ,combinations of ,arseniac ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,bases4 ,neutral ,salts4 ,lime ,arseniat of lime4 ,barytes barytes4 ,magnesia magnesia4 ,potash potash4 ,soda soda4 ,ammoniac ammoniac4 ,oxyd of zinc zinc4 manganese manganese4 iron iron4 lead lead4 tin tin4 cobalt cobalt4 copper copper4 nickel nickel4 bismuth bismuth4 mercury mercury4 antimony antimony4 silver silver4 gold gold4 platina platina4 ,argill argill4 ,note4--,this order of salts was entirely unknown to the antient chemists4 ,mr ,macquer1 in #agdf1 discovered the combinations of arseniac acid with potash and soda1 to which he gave the name of arsenical neutral salts4--,a4 ,,sect4 ,,xxiii4--,observations upon ,arseniac ,acid1 and its ,combinations4 ,in the ,collections of the ,academy for #agdf1 ,mr ,macquer shows that1 when a mixture of white oxyd of arsenic and nitre are subjected to the action of a strong fire1 a neutral salt is obtained1 which he calls neutral salt of arsenic4 ,at that time1 the cause of this singular phenomenon1 in which a metal acts the part of an acid1 was quite unknown2 but more modern experiments teach that1 during this process1 the arsenic becomes oxygenated1 by carrying off the oxygen of the nitric acid2 it is thus converted into a real acid1 and combines with the potash4 ,there are other methods now known for oxygenating arsenic1 and obtaining its acid free from combination4 ,the most simple and most effectual of these is as follows3 ,dissolve white oxyd of arsenic in three parts1 by weight1 of muriatic acid2 to this solution1 in a boiling state1 add two parts of nitric acid1 and evaporate to dryness4 ,in this process the nitric acid is decomposed1 its oxygen unites with the oxyd of arsenic1 and converts it into an acid1 and the nitrous radical flies off in the state of nitrous gas2 whilst the muriatic acid is converted by the heat into muriatic acid gas1 and may be collected in proper vessels4 ,the arseniac acid is entirely freed from the other acids employed during the process by heating it in a crucible till it begins to grow red2 what remains is pure concrete arseniac acid4 ,mr ,scheele's process1 which was repeated with great success by ,mr ,morveau1 in the laboratory at ,dijon1 is as follows3 ,distil muriatic acid from the black oxyd of manganese1 this converts it into oxygenated muriatic acid1 by carrying off the oxygen from the manganese1 receive this in a recipient containing white oxyd of arsenic1 covered by a little distilled water2 the arsenic decomposes the oxygenated muriatic acid1 by carrying off its supersaturation of oxygen1 the arsenic is converted into arseniac acid1 and the oxygenated muriatic acid is brought back to the state of common muriatic acid4 ,the two acids are separated by distillation1 with a gentle heat increased towards the end of the operation1 the muriatic acid passes over1 and the arseniac acid remains behind in a white concrete form4 ,the arseniac acid is considerably less volatile than white oxyd of arsenic2 it often contains white oxyd of arsenic in solution1 owing to its not being sufficiently oxygenated2 this is prevented by continuing to add nitrous acid1 as in the former process1 till no more nitrous gas is produced4 ,from all these observations ,i would give the following definition of arseniac acid4 ,it is a white concrete metallic acid1 formed by the combination of arsenic with oxygen1 fixed in a red heat1 soluble in water1 and capable of combining with many of the salifiable bases4 ,,sect4 ,,xxiv4--,observations upon ,molybdic ,acid1 and its ,combinations with ,acidifiable ,bases#dc4 ,molybdena is a particular metallic body1 capable of being oxygenated1 so far as to become a true concrete acid#dd4 ,for this purpose1 one part ore of molybdena1 which is a natural sulphuret of that metal1 is put into a retort1 with five or six parts nitric acid1 diluted with a quarter of its weight of water1 and heat is applied to the retort2 the oxygen of the nitric acid acts both upon the molybdena and the sulphur1 converting the one into molybdic1 and the other into sulphuric acid2 pour on fresh quantities of nitric acid so long as any red fumes of nitrous gas escape2 the molydbena is then oxygenated as far as is possible1 and is found at the bottom of the retort in a pulverulent form1 resembling chalk4 ,it must be washed in warm water1 to separate any adhering particles of sulphuric acid2 and1 as it is hardly soluble1 we lose very little of it in this operation4 ,all its combinations with salifiable bases were unknown to the ancient chemists4 ,,table of the ,combinations of ,tungstic ,acid with the ,salifiable ,bases4 ,bases4 ,neutral ,salts4 ,lime ,tungstat of lime4 ,barytes barytes4 ,magnesia magnesia4 ,potash potash4 ,soda soda4 ,ammoniac ammoniac4 ,argill argill4 ,oxyd of antimony7,a71 c4 antimony7,b71 c4 ,note ,a3 ,the combinations with metallic oxyds were set down by ,mr ,lavoisier in alphabetical order2 their order of affinity being unknown1 ,i have omitted them1 as serving no purpose4--,e4 ,note ,b3 ,all these salts were unknown to the ancient chemists4--,a4 ,,sect4 ,,xxv4--,observations upon ,tungstic ,acid1 and its ,combinations4 ,tungstein is a particular metal1 the ore of which has frequently been confounded with that of tin4 ,the specific gravity of this ore is to water as #f to #a2 in its form of cristallization it resembles the garnet1 and varies in colour from a pearl-white to yellow and reddish2 it is found in several parts of ,saxony and ,bohemia4 ,the mineral called ,wolfram1 which is frequent in the mines of ,cornwal1 is likewise an ore of this metal4 ,in all these ores the metal is oxydated2 and1 in some of them1 it appears even to be oxygenated to the state of acid1 being combined with lime into a true tungstat of lime4 ,to obtain the acid free1 mix one part of ore of tungstein with four parts of carbonat of potash1 and melt the mixture in a crucible1 then powder and pour on twelve parts of boiling water1 add nitric acid1 and the tungstic acid precipitates in a concrete form4 ,afterwards1 to insure the complete oxygenation of the metal1 add more nitric acid1 and evaporate to dryness1 repeating this operation so long as red fumes of nitrous gas are produced4 ,to procure tungstic acid perfectly pure1 the fusion of the ore with carbonat of potash must be made in a crucible of platina1 otherwise the earth of the common crucibles will mix with the products1 and adulterate the acid4 ,,table of the ,combinations of ,tartarous ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,bases4 ,neutral ,salts4 ,lime ,tartarite of lime4 ,barytes barytes4 ,magnesia magnesia4 ,potash potash4 ,soda soda4 ,ammoniac ammoniac4 ,argill argill4 ,oxyd of zinc zinc4 iron iron4 manganese manganese4 cobalt cobalt4 nickel nickel4 lead lead4 tin tin4 copper copper4 bismuth bismuth4 antimony antimony4 arsenic arsenic4 silver silver4 mercury mercury4 gold gold4 platina platina4 ,,sect4 ,,xxvi4--,observations upon ,tartarous ,acid1 and its ,combinations4 ,tartar1 or the concretion which fixes to the inside of vessels in which the fermentation of wine is completed1 is a well known salt1 composed of a peculiar acid1 united in considerable excess to potash4 ,mr ,scheele first pointed out the method of obtaining this acid pure4 ,having observed that it has a greater affinity to lime than to potash1 he directs us to proceed in the following manner4 ,dissolve purified tartar in boiling water1 and add a sufficient quantity of lime till the acid be completely saturated4 ,the tartarite of lime which is formed1 being almost insoluble in cold water1 falls to the bottom1 and is separated from the solution of potash by decantation2 it is afterwards washed in cold water1 and dried2 then pour on some sulphuric acid1 diluted with eight or nine parts of water1 digest for twelve hours in a gentle heat1 frequently stirring the mixture2 the sulphuric acid combines with the lime1 and the tartarous acid is left free4 ,a small quantity of gas1 not hitherto examined1 is disengaged during this process4 ,at the end of twelve hours1 having decanted off the clear liquor1 wash the sulphat of lime in cold water1 which add to the decanted liquor1 then evaporate the whole1 and the tartarous acid is obtained in a concrete form4 ,two pounds of purified tartar1 by means of from eight to ten ounces of sulphuric acid1 yield about eleven ounces of tartarous acid4 ,as the combustible radical exists in excess1 or as the acid from tartar is not fully saturated with oxygen1 we call it tartarous acid1 and the neutral salts formed by its combinations with salifiable bases tartarites4 ,the base of the tartarous acid is a carbono-hydrous or hydro-carbonous radical1 less oxygenated than in the oxalic acid2 and it would appear1 from the experiments of ,mr ,hassenfratz1 that azote enters into the composition of the tartarous radical1 even in considerable quantity4 ,by oxygenating the tartarous acid1 it is convertible into oxalic1 malic1 and acetous acids2 but it is probable the proportions of hydrogen and charcoal in the radical are changed during these conversions1 and that the difference between these acids does not alone consist in the different degrees of oxygenation4 ,the tartarous acid is susceptible of two degrees of saturation in its combinations with the fixed alkalies2 by one of these a salt is formed with excess of acid1 improperly called cream of tartar1 which in our new nomenclature is named acidulous tartarite of potash2 by a second or equal degree of saturation a perfectly neutral salt is formed1 formerly called vegetable salt1 which we name tartarite of potash4 ,with soda this acid forms tartarite of soda1 formerly called sal de ,seignette1 or sal polychrest of ,rochell4 ,,sect4 ,,xxvii4--,observations upon ,malic ,acid1 and its ,combinations with the ,salifiable ,bases#de4 ,the malic acid exists ready formed in the sour juice of ripe and unripe apples1 and many other fruits1 and is obtained as follows3 ,saturate the juice of apples with potash or soda1 and add a proper proportion of acetite of lead dissolved in water2 a double decomposition takes place1 the malic acid combines with the oxyd of lead and precipitates1 being almost insoluble1 and the acetite of potash or soda remains in the liquor4 ,the malat of lead being separated by decantation1 is washed with cold water1 and some dilute sulphuric acid is added2 this unites with the lead into an insoluble sulphat1 and the malic acid remains free in the liquor4 ,this acid1 which is found mixed with citric and tartarous acid in a great number of fruits1 is a kind of medium between oxalic and acetous acids being more oxygenated than the former1 and less so than the latter4 ,from this circumstance1 ,mr ,hermbstadt calls it imperfect vinegar2 but it differs likewise from acetous acid1 by having rather more charcoal1 and less hydrogen1 in the composition of its radical4 ,when an acid much diluted has been used in the foregoing process1 the liquor contains oxalic as well as malic acid1 and probably a little tartarous1 these are separated by mixing lime-water with the acids1 oxalat1 tartarite1 and malat of lime are produced2 the two former1 being insoluble1 are precipitated1 and the malat of lime remains dissolved2 from this the pure malic acid is separated by the acetite of lead1 and afterwards by sulphuric acid1 as directed above4 ,,table of the ,combinations of ,citric ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity7,a74 ,bases4 ,neutral ,salts4 ,barytes ,citrat of barytes4 ,lime lime4 ,magnesia magnesia4 ,potash potash4 ,soda soda4 ,ammoniac ammoniac4 ,oxyd of zinc zinc4 manganese manganese4 iron iron4 lead lead4 cobalt cobalt4 copper copper4 arsenic arsenic4 mercury mercury4 antimony antimony4 silver silver4 gold gold4 platina platina4 ,argill argill4 ,note ,a3 ,these combinations were unknown to the ancient chemists4 ,the order of affinity of the salifiable bases with this acid was determined by ,mr ,bergman and by ,mr de ,breney of the ,dijon ,academy4--,a4 ,,sect4 ,,xxviii4--,observations upon ,citric ,acid1 and its ,combinations4 ,the citric acid is procured by expression from lemons1 and is found in the juices of many other fruits mixed with malic acid4 ,to obtain it pure and concentrated1 it is first allowed to depurate from the mucous part of the fruit by long rest in a cool cellar1 and is afterwards concentrated by exposing it to the temperature of #d or #e degrees below ,zero1 from #ba to #bc of ,fahrenheit1 the water is frozen1 and the acid remains liquid1 reduced to about an eighth part of its original bulk4 ,a lower degree of cold would occasion the acid to be engaged amongst the ice1 and render it difficultly separable4 ,this process was pointed out by ,mr ,georgius4 ,it is more easily obtained by saturating the lemon-juice with lime1 so as to form a citrat of lime1 which is insoluble in water2 wash this salt1 and pour on a proper quantity of sulphuric acid2 this forms a sulphat of lime1 which precipitates and leaves the citric acid free in the liquor4 ,,table of the ,combinations of ,pyro-lignous ,acid with the ,salifiable ,bases1 in the ,order of ,affinity7,a74 ,bases4 ,neutral ,salts4 ,lime ,pyro-mucite of lime4 ,barytes barytes4 ,potash potash4 ,soda soda4 ,magnesia magnesia4 ,ammoniac ammoniac4 ,oxyd of zinc zinc4 manganese manganese4 iron iron4 lead lead4 tin tin4 cobalt cobalt4 copper copper4 nickel nickel4 arsenic arsenic4 bismuth bismuth4 mercury mercury4 antimony antimony4 silver silver4 gold gold4 platina platina4 ,argill argill4 ,note ,a3 ,the above affinities were determined by ,messrs de ,morveau and ,elo,i ,boursier de ,clervaux4 ,these combinations were entirely unknown till lately4--,a4 ,,sect4 ,,xxix4--,observations upon ,pyro-lignous ,acid1 and its ,combinations4 ,the ancient chemists observed that most of the woods1 especially the more heavy and compact ones1 gave out a particular acid spirit1 by distillation1 in a naked fire2 but1 before ,mr ,goetling1 who gives an account of his experiments upon this subject in ,crell's ,chemical ,journal for #aggi1 no one had ever made any inquiry into its nature and properties4 ,this acid appears to be the same1 whatever be the wood it is procured from4 ,when first distilled1 it is of a brown colour1 and considerably impregnated with charcoal and oil2 it is purified from these by a second distillation4 ,the pyro-lignous radical is chiefly composed of hydrogen and charcoal4 ,,sect4 ,,xxx4--,observations upon ,pyro-tartarous ,acid1 and its ,combinations with the ,salifiable ,bases#df4 ,the name of ,pyro-tartarous acid is given to a dilute empyreumatic acid obtained from purified acidulous tartarite of potash by distillation in a naked fire4 ,to obtain it1 let a retort be half filled with powdered tartar1 adapt a tubulated recipient1 having a bent tube communicating with a bell-glass in a pneumato-chemical apparatus2 by gradually raising the fire under the retort1 we obtain the pyro-tartarous acid mixed with oil1 which is separated by means of a funnel4 ,a vast quantity of carbonic acid gas is disengaged during the distillation4 ,the acid obtained by the above process is much contaminated with oil1 which ought to be separated from it4 ,some authors advise to do this by a second distillation2 but the ,dijon academicians inform us1 that this is attended with great danger from explosions which take place during the process4 ,,table of the ,combinations of ,pyro-mucous ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity7,a74 ,bases4 ,neutral ,salts4 ,potash ,pyro-mucite of potash4 ,soda soda4 ,barytes barytes4 ,lime lime4 ,magnesia magnesia4 ,ammoniac ammoniac4 ,argill argill4 ,oxyd of zinc zinc4 manganese manganese4 iron iron4 lead lead4 tin tin4 cobalt cobalt4 copper copper4 nickel nickel4 arsenic arsenic4 bismuth bismuth4 antimony antimony4 ,note ,a3 ,all these combinations were unknown to the ancient chemists4--,a4 ,,sect4 ,,xxxi4--,observations upon ,pyro-mucous ,acid1 and its ,combinations4 ,this acid is obtained by distillation in a naked fire from sugar1 and all the saccharine bodies2 and1 as these substances swell greatly in the fire1 it is necessary to leave seven-eighths of the retort empty4 ,it is of a yellow colour1 verging to red1 and leaves a mark upon the skin1 which will not remove but alongst with the epidermis4 ,it may be procured less coloured1 by means of a second distillation1 and is concentrated by freezing1 as is directed for the citric acid4 ,it is chiefly composed of water and oil slightly oxygenated1 and is convertible into oxalic and malic acids by farther oxygenation with the nitric acid4 ,it has been pretended that a large quantity of gas is disengaged during the distillation of this acid1 which is not the case if it be conducted slowly1 by means of moderate heat4 ,,table of the ,combinations of the ,oxalic ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity7,a74 ,bases4 ,neutral ,salts4 ,lime ,oxalat of lime4 ,barytes barytes4 ,magnesia magnesia4 ,potash potash4 ,soda soda4 ,ammoniac ammoniac4 ,argill argill4 ,oxyd of zinc zinc4 iron iron4 manganese manganese4 cobalt cobalt4 nickel nickel4 lead lead4 copper copper4 bismuth bismuth4 antimony antimony4 arsenic arsenic4 mercury mercury4 silver silver4 gold gold4 platina platina4 ,note ,a3 ,all unknown to the ancient chemists4--,a4 ,,sect4 ,,xxxii4--,observations upon ,oxalic ,acid1 and its ,combinations4 ,the oxalic acid is mostly prepared in ,switzerland and ,germany from the expressed juice of sorrel1 from which it cristallizes by being left long at rest2 in this state it is partly saturated with potash1 forming a true acidulous oxalat of potash1 or salt with excess of acid4 ,to obtain it pure1 it must be formed artificially by oxygenating sugar1 which seems to be the true oxalic radical4 ,upon one part of sugar pour six or eight parts of nitric acid1 and apply a gentle heat2 a considerable effervescence takes place1 and a great quantity of nitrous gas is disengaged2 the nitric acid is decomposed1 and its oxygen unites to the sugar3 ,by allowing the liquor to stand at rest1 cristals of pure oxalic acid are formed1 which must be dried upon blotting paper1 to separate any remaining portions of nitric acid2 and1 to ensure the purity of the acid1 dissolve the cristals in distilled water1 and cristallize them afresh4 ---------------------------------------- -------------------------------- ,bases4 ,neutral salts4 ,names of the resulting neutral salts according to the old nomenclature4 ---------------------------------------- -------------------------------- ,barytes ,acetite of barytes,unknown to the ancients4 ,discovered by ,mr de ,morveau1 who calls it barotic acte4 ,potash ---- potash ,secret terra foliata tartari of ,muller4 ,arcanum tartari of ,basil ,valentin and ,paracelsus4 ,purgative magistery of tartar of ,schroder4 ,essential salt of wine of ,zwelfer4 ,regenerated tartar of ,tachenius4 ,diuretic salt of ,sylvius and ,wilson4 ,soda ---- soda ,foliated earth with base of mineral alkali4 ,mineral or crystallisable foliated earth4 ,mineral acetous salt4 ,lime ---- lime ,salt of chalk1 coral1 or crabs eyes2 mentioned by ,hartman4 ,magnesia ---- magnesia ,first mentioned by ,mr ,wenzel4 ,ammoniac ---- ammoniac ,spiritus ,mindereri4 ,ammoniacal acetous salt4 ,oxyd of zinc ---- zinc ,known to ,glauber1 ,schwedemberg1 ,respour1 ,pott1 de ,lassone1 and ,wenzel1 but not named4 ---- manganese ---- manganese ,unknown to the ancients4 ---- iron ---- iron ,martial vinegar4 ,described by ,monnet1 ,wenzel1 and the ,duke d',ayen4 ---- lead ---- lead ,sugar1 vinegar1 and salt of lead or ,saturn4 ---- tin ---- tin ,known to ,lemery1 ,margraff1 ,monnet1 ,weslendorf1 and ,wenzel1 but not named4 ---- cobalt ---- cobalt ,sympathetic ink of ,mr ,cadet4 ---- copper ---- copper ,verdigris1 crystals of verditer1 verditer1 distilled verdigris1 crystals of ,venus or of copper4 ---- nickel ---- nickel ,unknown to the ancients4 ---- arsenic ---- arsenic ,arsenico-acetous fuming liquor1 liquid phosphorus of ,mr ,cadet4 ---- bismuth ---- bismuth ,sugar of bismuth of ,mr ,geoffroi4 ,known to ,gellert1 ,pott1 ,weslendorf1 ,bergman1 and de ,morveau4 ---- mercury ---- mercury ,mercurial foliated earth1 ,keyser's famous antivenereal remedy4 ,mentioned by ,gebaver in #agdh2 known to ,helot1 ,margraff1 ,baum1 ,bergman1 and de ,morveau4 ---- antimony ---- antimony ,unknown4 ---- silver ---- silver ,described by ,margraff1 ,monnet1 and ,wenzel2 unknown to the ancients4 ---- gold ---- gold ,little known1 mentioned by ,schroder and ,juncker4 ---- platina ---- platina ,unknown4 ,argill ---- argill ,according to ,mr ,wenzel1 vinegar dissolves only a very small proportion of argill4 ---------------------------------------- -------------------------------- ,from the liquor remaining after the first cristallization of the oxalic acid we may obtain malic acid by refrigeration3 ,this acid is more oxygenated than the oxalic2 and1 by a further oxygenation1 the sugar is convertible into acetous acid1 or vinegar4 ,the oxalic acid1 combined with a small quantity of soda or potash1 has the property1 like the tartarous acid1 of entering into a number of combinations without suffering decomposition3 ,these combinations form triple salts1 or neutral salts with double bases1 which ought to have proper names4 ,the salt of sorrel1 which is potash having oxalic acid combined in excess1 is named acidulous oxalat of potash in our new nomenclature4 ,the acid procured from sorrel has been known to chemists for more than a century1 being mentioned by ,mr ,duclos in the ,memoirs of the ,academy for #afhh1 and was pretty accurately described by ,boerhaave2 but ,mr ,scheele first showed that it contained potash1 and demonstrated its identity with the acid formed by the oxygenation of sugar4 ,,sect4 ,,xxxiii4--,observations upon ,acetous ,acid1 and its ,combinations4 ,this acid is composed of charcoal and hydrogen united together1 and brought to the state of an acid by the addition of oxygen2 it is consequently formed by the same elements with the tartarous oxalic1 citric1 malic acids1 and others1 but the elements exist in different proportions in each of these2 and it would appear that the acetous acid is in a higher state of oxygenation than these other acids4 ,i have some reason to believe that the acetous radical contains a small portion of azote2 and1 as this element is not contained in the radicals of any vegetable acid except the tartarous1 this circumstance is one of the causes of difference4 ,the acetous acid1 or vinegar1 is produced by exposing wine to a gentle heat1 with the addition of some ferment3 ,this is usually the ley1 or mother1 which has separated from other vinegar during fermentation1 or some similar matter4 ,the spiritous part of the wine1 which consists of charcoal and hydrogen1 is oxygenated1 and converted into vinegar3 ,this operation can only take place with free access of air1 and is always attended by a diminution of the air employed in consequence of the absorption of oxygen2 wherefore1 it ought always to be carried on in vessels only half filled with the vinous liquor submitted to the acetous fermentation4 ,the acid formed during this process is very volatile1 is mixed with a large proportion of water1 and with many foreign substances2 and1 to obtain it pure1 it is distilled in stone or glass vessels by a gentle fire4 ,the acid which passes over in distillation is somewhat changed by the process1 and is not exactly of the same nature with what remains in the alembic1 but seems less oxygenated3 ,this circumstance has not been formerly observed by chemists4 ,distillation is not sufficient for depriving this acid of all its unnecessary water2 and1 for this purpose1 the best way is by exposing it to a degree of cold from #d to #f below the freezing point1 from #ai to #bc of ,fahrenheit2 by this means the aqueous part becomes frozen1 and leaves the acid in a liquid state1 and considerably concentrated4 ,in the usual temperature of the air1 this acid can only exist in the gasseous form1 and can only be retained by combination with a large proportion of water4 ,there are other chemical processes for obtaining the acetous acid1 which consist in oxygenating the tartarous1 oxalic1 or malic acids1 by means of nitric acid2 but there is reason to believe the proportions of the elements of the radical are changed during this process4 ,mr ,hassenfratz is at present engaged in repeating the experiments by which these conversions are said to be produced4 ,the combinations of acetous acid with the various salifiable bases are very readily formed2 but most of the resulting neutral salts are not cristallizable1 whereas those produced by the tartarous and oxalic acids are1 in general1 hardly soluble4 ,tartarite and oxalat of lime are not soluble in any sensible degree3 ,the malats are a medium between the oxalats and acetites1 with respect to solubility1 and the malic acid is in the middle degree of saturation between the oxalic and acetous acids4 ,with this1 as with all the acids1 the metals require to be oxydated previous to solution4 ,the ancient chemists knew hardly any of the salts formed by the combinations of acetous acid with the salifiable bases1 except the acetites of potash1 soda1 ammoniac1 copper1 and lead4 ,mr ,cadet discovered the acetite of arsenic#dg2 ,mr ,wenzel1 the ,dijon academicians ,mr de ,lassone1 and ,mr ,proust1 made us acquainted with the properties of the other acetites4 ,from the property which acetite of potash possesses1 of giving out ammoniac in distillation1 there is some reason to suppose1 that1 besides charcoal and hydrogen1 the acetous radical contains a small proportion of azote1 though it is not impossible but the above production of ammoniac may be occasioned by the decomposition of the potash4 ,,table of the ,combinations of ,acetic ,acid with the ,salifiable ,bases1 in the order of affinity4 ,bases4 ,neutral ,salts4 ,barytes ,acetat of barytes4 ,potash potash4 ,soda soda4 ,lime lime4 ,magnesia magnesia4 ,ammoniac ammoniac4 ,oxyd of zinc zinc4 manganese manganese4 iron iron4 lead lead4 tin tin4 cobalt cobalt4 copper copper4 nickel nickel4 arsenic arsenic4 bismuth bismuth4 mercury mercury4 antimony antimony4 silver silver4 gold gold4 platina platina4 ,argill argill4 ,note4--,all these salts were unknown to the ancients2 and even those chemists who are most versant in modern discoveries1 are yet at a lose whether the greater part of the salts produced by the oxygenated acetic radical belong properly to the class of acetites1 or to that of acetats4--,a4 ,,sect4 ,,xxxiv4--,observations upon ,acetic ,acid1 and its ,combinations4 ,we have given to radical vinegar the name of acetic acid1 from supposing that it consists of the same radical with that of the acetous acid1 but more highly saturated with oxygen4 ,according to this idea1 acetic acid is the highest degree of oxygenation of which the hydro-carbonous radical is susceptible2 but1 although this circumstance be extremely probable1 it requires to be confirmed by farther1 and more decisive experiments1 before it be adopted as an absolute chemical truth4 ,we procure this acid as follows3 ,upon three parts acetite of potash or of copper1 pour one part of concentrated sulphuric acid1 and1 by distillation1 a very highly concentrated vinegar is obtained1 which we call acetic acid1 formerly named radical vinegar4 ,it is not hitherto rigorously proved that this acid is more highly oxygenated than the acetous acid1 nor that the difference between them may not consist in a different proportion between the elements of the radical or base4 ,,table of the ,combinations of ,succinic ,acid with the ,salifiable ,bases1 in the order of ,affinity4 ,bases4 ,neutral ,salts4 ,barytes ,succinat of barytes4 ,lime lime4 ,potash potash4 ,soda soda4 ,ammoniac ammoniac4 ,magnesia magnesia4 ,argill argill4 ,oxyd of zinc zinc4 iron iron4 manganese manganese4 cobalt cobalt4 nickel nickel4 lead lead4 tin tin4 copper copper4 bismuth bismuth4 antimony antimony4 arsenic arsenic4 mercury mercury4 silver silver4 gold gold4 platina platina4 ,note4--,all the succinats were unknown to the ancient chemists4--,a4 ,,sect4 ,,xxxv4--,observations upon ,succinic ,acid1 and its ,combinations4 ,the succinic acid is drawn from amber by sublimation in a gentle heat1 and rises in a concrete form into the neck of the subliming vessel4 ,the operation must not be pushed too far1 or by too strong a fire1 otherwise the oil of the amber rises alongst with the acid4 ,the salt is dried upon blotting paper1 and purified by repeated solution and crystallization4 ,this acid is soluble in twenty-four times its weight of cold water1 and in a much smaller quantity of hot water4 ,it possesses the qualities of an acid in a very small degree1 and only affects the blue vegetable colours very slightly4 ,the affinities of this acid1 with the salifiable bases1 are taken from ,mr de ,morveau1 who is the first chemist that has endeavoured to ascertain them4 ,,sect4 ,,xxxvi4--,observations upon ,benzoic ,acid1 and its ,combinations with ,salifiable ,bases#dh4 ,this acid was known to the ancient chemists under the name of ,flowers of ,benjamin1 or of ,benzoin1 and was procured1 by sublimation1 from the gum or resin called ,benzoin3 ,the means of procuring it1 via humida1 was discovered by ,mr ,geoffroy1 and perfected by ,mr ,scheele4 ,upon benzoin1 reduced to powder1 pour strong lime-water1 having rather an excess of lime2 keep the mixture continually stirring1 and1 after half an hour's digestion1 pour off the liquor1 and use fresh portions of lime-water in the same manner1 so long as there is any appearance of neutralization4 ,join all the decanted liquors1 and evaporate1 as far as possible1 without occasioning cristallization1 and1 when the liquor is cold1 drop in muriatic acid till no more precipitate is formed4 ,by the former part of the process a benzoat of lime is formed1 and1 by the latter1 the muriatic acid combines with the lime1 forming muriat of lime1 which remains dissolved1 while the benzoic acid1 being insoluble1 precipitates in a concrete state4 ,,sect4 ,,xxxvii4--,observations upon ,camphoric ,acid1 and its ,combinations with ,salifiable ,bases#di4 ,camphor is a concrete essential oil1 obtained1 by sublimation1 from a species of laurus which grows in ,china and ,japan4 ,by distilling nitric acid eight times from camphor1 ,mr ,kosegarten converted it into an acid analogous to the oxalic2 but1 as it differs from that acid in some circumstances1 we have thought necessary to give it a particular name1 till its nature be more completely ascertained by farther experiment4 ,as camphor is a carbono-hydrous or hydro-carbonous radical1 it is easily conceived1 that1 by oxygenation1 it should form oxalic1 malic1 and several other vegetable acids3 ,this conjecture is rendered not improbable by the experiments of ,mr ,kosegarten2 and the principal phenomena exhibited in the combinations of camphoric acid with the salifiable bases1 being very similar to those of the oxalic and malic acids1 lead me to believe that it consists of a mixture of these two acids4 ,,sect4 ,,xxxviii4--,observations upon ,gallic ,acid1 and its ,combinations with ,salifiable ,bases#ej4 ,the ,gallic acid1 formerly called ,principle of ,astringency1 is obtained from gall nuts1 either by infusion or decoction with water1 or by distillation with a very gentle heat4 ,this acid has only been attended to within these few years4 ,the ,committee of the ,dijon ,academy have followed it through all its combinations1 and give the best account of it hitherto produced4 ,its acid properties are very weak2 it reddens the tincture of turnsol1 decomposes sulphurets1 and unites to all the metals when they have been previously dissolved in some other acid4 ,iron1 by this combination1 is precipitated of a very deep blue or violet colour4 ,the radical of this acid1 if it deserves the name of one1 is hitherto entirely unknown2 it is contained in oak willow1 marsh iris1 the strawberry1 nymphea1 ,peruvian bark1 the flowers and bark of pomgranate1 and in many other woods and barks4 ,,sect4 ,,xxxix4--,observations upon ,lactic ,acid1 and its ,combinations with ,salifiable ,bases#ea4 ,the only accurate knowledge we have of this acid is from the works of ,mr ,scheele4 ,it is contained in whey1 united to a small quantity of earth1 and is obtained as follows3 ,reduce whey to one eighth part of its bulk by evaporation1 and filtrate1 to separate all its cheesy matter2 then add as much lime as is necessary to combine with the acid2 the lime is afterwards disengaged by the addition of oxalic acid1 which combines with it into an insoluble neutral salt4 ,when the oxalat of lime has been separated by decantation1 evaporate the remaining liquor to the consistence of honey2 the lactic acid is dissolved by alkohol1 which does not unite with the sugar of milk and other foreign matters2 these are separated by filtration from the alkohol and acid2 and the alkohol being evaporated1 or distilled off1 leaves the lactic acid behind4 ,this acid unites with all the salifiable bases forming salts which do not cristallize2 and it seems considerably to resemble the acetous acid4 ,,table of the ,combinations of ,saccholactic ,acid with the ,salifiable ,bases1 in the ,order of ,affinity4 ,bases4 ,neutral ,salts4 ,lime ,saccholat of lime4 ,barytes barytes4 ,magnesia magnesia4 ,potash potash4 ,soda soda4 ,ammoniac ammoniac4 ,argill argill4 ,oxyd of zinc zinc4 manganese manganese4 iron iron4 lead lead4 tin tin4 cobalt cobalt4 copper copper4 nickel nickel4 arsenic arsenic4 bismuth bismuth4 mercury mercury4 antimony antimony4 silver silver4 ,note4--,all these were unknown to the ancient chemists4--,a4 ,,sect4 ,,xl4--,observations upon ,saccholactic ,acid1 and its ,combinations4 ,a species of sugar may be extracted1 by evaporation1 from whey1 which has long been known in pharmacy1 and which has a considerable resemblance to that procured from sugar canes4 ,this saccharine matter1 like ordinary sugar1 may be oxygenated by means of nitric acid3 ,for this purpose1 several portions of nitric acid are distilled from it2 the remaining liquid is evaporated1 and set to cristallize1 by which means cristals of oxalic acid are procured2 at the same time a very fine white powder precipitates1 which is the saccholactic acid discovered by ,scheele4 ,it is susceptible of combining with the alkalies1 ammoniac1 the earths1 and even with the metals3 ,its action upon the latter is hitherto but little known1 except that1 with them1 it forms difficultly soluble salts4 ,the order of affinity in the table is taken from ,bergman4 ,,table of the ,combinations of ,formic ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,bases4 ,neutral ,salts4 ,barytes ,formiat of barytes4 ,potash potash4 ,soda soda4 ,lime lime4 ,magnesia magnesia4 ,ammoniac ammoniac4 ,oxyd of zinc zinc4 manganese manganese4 iron iron4 lead lead4 tin tin4 cobalt cobalt4 copper copper4 nickel nickel4 bismuth bismuth4 silver silver4 ,argill argill4 ,note4--,all unknown to the ancient chemists4--,a4 ,,sect4 ,,xli4--,observations upon ,formic ,acid1 and its ,combinations4 ,this acid was first obtained by distillation from ants1 in the last century1 by ,samuel ,fisher4 ,the subject was treated of by ,margraff in #agdi1 and by ,messrs ,ardwisson and ,ochrn of ,leipsic in #aggg4 ,the formic acid is drawn from a large species of red ants1 formica rufa1 ,lin4 which form large ant hills in woody places4 ,it is procured1 either by distilling the ants with a gentle heat in a glass retort or an alembic2 or1 after having washed the ants in cold water1 and dried them upon a cloth1 by pouring on boiling water1 which dissolves the acid2 or the acid may be procured by gentle expression from the insects1 in which case it is stronger than in any of the former ways4 ,to obtain it pure1 we must rectify1 by means of distillation1 which separates it from the uncombined oily and charry matter2 and it may be concentrated by freezing1 in the manner recommended for treating the acetous acid4 ,,sect4 ,,xlii4--,observations upon ,bombic ,acid1 and its ,combinations with ,acidifiable ,bases#eb4 ,the juices of the silk worm seem to assume an acid quality when that insect changes from a larva to a chrysalis4 ,at the moment of its escape from the latter to the butterfly form1 it emits a reddish liquor which reddens blue paper1 and which was first attentively observed by ,mr ,chaussier of the ,dijon academy1 who obtains the acid by infusing silk worm chrysalids in alkohol1 which dissolves their acid without being charged with any of the gummy parts of the insect2 and1 by evaporating the alkohol1 the acid remains tollerably pure4 ,the properties and affinities of this acid are not hitherto ascertained with any precision2 and we have reason to believe that analogous acids may be procured from other insects4 ,the radical of this acid is probably1 like that of the other acids from the animal kingdom1 composed of charcoal1 hydrogen1 and azote1 with the addition1 perhaps1 of phosphorus4 ,,table of the ,combinations of ,sebacic ,acid1 with the ,salifiable ,bases1 in the ,order of ,affinity4 ,bases4 ,neutral ,salts4 ,barytes ,sebat of barytes4 ,potash potash4 ,soda soda4 ,lime lime4 ,magnesia magnesia4 ,ammoniac ammoniac4 ,argill argill4 ,oxyd of zinc zinc4 manganese manganese4 iron iron4 lead lead4 tin tin4 cobalt cobalt4 copper copper4 nickel nickel4 arsenic arsenic4 bismuth bismuth4 mercury mercury4 antimony antimony4 silver silver4 ,note4--,all these were unknown to the ancient chemists4--,a4 ,,sect4 ,,xliii4--,observations upon ,sebacid ,acid1 and its ,combinations4 ,to obtain the sebacic acid1 let some suet be melted in a skillet over the fire1 alongst with some quick-lime in fine powder1 and constantly stirred1 raising the fire towards the end of the operation1 and taking care to avoid the vapours1 which are very offensive4 ,by this process the sebacic acid unites with the lime into a sebat of lime1 which is difficultly soluble in water2 it is1 however1 separated from the fatty matters with which it is mixed by solution in a large quantity of boiling water4 ,from this the neutral salt is separated by evaporation2 and1 to render it pure1 is calcined1 redissolved1 and again cristallized4 ,after this we pour on a proper quantity of sulphuric acid1 and the sebacic acid passes over by distillation4 ,,sect4 ,,xliv4--,observations upon the ,lithic ,acid1 and its ,combinations with the ,salifiable ,bases#ec4 ,from the later experiments of ,bergman and ,scheele1 the urinary calculus appears to be a species of salt with an earthy basis2 it is slightly acidulous1 and requires a large quantity of water for solution1 three grains being scarcely soluble in a thousand grains of boiling water1 and the greater part again cristallizes when cold4 ,to this concrete acid1 which ,mr de ,morveau calls ,lithiasic ,acid1 we give the name of ,lithic ,acid1 the nature and properties of which are hitherto very little known4 ,there is some appearance that it is an acidulous neutral salt1 or acid combined in excess with a salifiable base2 and ,i have reason to believe that it really is an acidulous phosphat of lime2 if so1 it must be excluded from the class of peculiar acids4 ,,table of the ,combinations of the ,prussic ,acid with the ,salifiable ,bases1 in the order of affinity4 ,bases4 ,neutral ,salts4 ,potash ,prussiat of potash4 ,soda soda4 ,ammoniac ammoniac4 ,lime lime4 ,barytes barytes4 ,magnesia magnesia4 ,oxyd of zinc zinc4 iron iron4 manganese manganese4 cobalt cobalt4 nickel nickel4 lead lead4 tin tin4 copper copper4 bismuth bismuth4 antimony antimony4 arsenic arsenic4 silver silver4 mercury mercury4 gold gold4 platina platina4 ,note4---,all these were unknown to former chemists4--,a4 ,observations upon the ,prussic ,acid1 and its ,combinations4 ,as the experiments which have been made hitherto upon this acid seem still to leave a considerable degree of uncertainty with regard to its nature1 ,i shall not enlarge upon its properties1 and the means of procuring it pure and dissengaged from combination4 ,it combines with iron1 to which it communicates a blue colour1 and is equally susceptible of entering into combination with most of the other metals1 which are precipitated from it by the alkalies1 ammoniac1 and lime1 in consequence of greater affinity4 ,the ,prussic radical1 from the experiments of ,scheele1 and especially from those of ,mr ,berthollet1 seems composed of charcoal and azote2 hence it is an acid with a double base4 ,the phosphorus which has been found combined with it appears1 from the experiments of ,mr ,hassenfratz1 to be only accidental4 ,although this acid combines with alkalies1 earths1 and metals1 in the same way with other acids1 it possesses only some of the properties we have been in use to attribute to acids1 and it may consequently be improperly ranked here in the class of acids2 but1 as ,i have already observed1 it is difficult to form a decided opinion upon the nature of this substance until the subject has been farther elucidated by a greater number of experiments4 ,,footnotes3 #cf ,see ,memoirs of the ,academy for #aggf1 p4 #fga4 and for #aggh1 p4 #ece1--;,a4 #cg ,see ,part ,i4 ,chap4 ,,xi4 upon this subject4--,a4 #ch ,see ,part ,i4 ,chap4 ,,xi4 upon the application of these names according to the proportions of the two ingredients4--,a #ci ,see ,part ,i4 ,chap4 ,,xii4 upon this subject4--,a4 #dj ,those who wish to see what has been said upon this great chemical question by ,messrs de ,morveau1 ,berthollet1 ,de ,fourcroy1 and myself1 may consult our translation of ,mr ,kirwan's ,essay upon ,phlogiston4--,a4 #da ,saltpetre is likewise procured in large quantities by lixiviating the natural soil in some parts of ,bengal1 and of the ,russian ,ukrain4--,e4 #db ,commonly called ,derbyshire spars4--,e4 #dc ,i have not added the ,table of these combinations1 as the order of their affinity is entirely unknown2 they are called molybdats of argil1 antimony1 potash1 c4--,e4 #dd ,this acid was discovered by ,mr ,scheele1 to whom chemistry is indebted for the discovery of several other acids4--,a4 #de ,i have omitted the ,table1 as the order of affinity is unknown1 and is given by ,mr ,lavoisier only in alphabetical order4 ,all the combinations of malic acid with salifiable bases1 which are named malats1 were unknown to the ancient chemists4--,e4 #df ,the order of affinity of the salifiable bases with this acid is hitherto unknown4 ,mr ,lavoisier1 from its similarity to pyro-lignous acid1 supposes the order to be the same in both2 but1 as this is not ascertained by experiment1 the table is omitted4 ,all these combinations1 called ,pyro-tartarites1 were unknown till lately--,e4 #dg ,savans ,etrangers1 ,vol4 ,,iii4 #dh ,these combinations are called ,benzoats of ,lime1 ,potash1 ,zinc1 c42 but1 as the order of affinity is unknown1 the alphabetical table is omitted1 as unnecessary4--,e4 #di ,these combinations1 which were all unknown to the ancients1 are called ,camphorats4 ,the table is omitted1 as being only in alphabetical order4--,e4 #ej ,these combinations1 which are called ,gallats1 were all unknown to the ancients2 and the order of their affinity is not hitherto established4--,a4 #ea ,these combinations are called ,lactats2 they were all unknown to the ancient chemists1 and their affinities have not yet been ascertained4--,a4 #eb ,these combinations named ,bombats were unknown to the ancient chemists2 and the affinities of the salifiable bases with the bombic acid are hitherto undetermined4--,a4 #ec ,all the combinations of this acid1 should it finally turn out to be one1 were unknown to the ancient chemists1 and its affinities with the salifiable bases have not been hitherto determined4--,a4 ,,part ,,iii4 ,description of the ,instruments and ,operations of ,chemistry4 ,,introduction4 ,in the two former parts of this work ,i designedly avoided being particular in describing the manual operations of chemistry1 because ,i had found from experience1 that1 in a work appropriated to reasoning1 minute descriptions of processes and of plates interrupt the chain of ideas1 and render the attention necessary both difficult and tedious to the reader4 ,on the other hand1 if ,i had confined myself to the summary descriptions hitherto given1 beginners could have only acquired very vague conceptions of practical chemistry from my work1 and must have wanted both confidence and interest in operations they could neither repeat nor thoroughly comprehend4 ,this want could not have been supplied from books2 for1 besides that there are not any which describe the modern instruments and experiments sufficiently at large1 any work that could have been consulted would have presented these things under a very different order of arrangement1 and in a different chemical language1 which must greatly tend to injure the main object of my performance4 ,influenced by these motives1 ,i determined to reserve1 for a third part of my work1 a summary description of all the instruments and manipulations relative to elementary chemistry4 ,i considered it as better placed at the end1 rather than at the beginning of the book1 because ,i must have been obliged to suppose the reader acquainted with circumstances which a beginner cannot know1 and must therefore have read the elementary part to become acquainted with4 ,the whole of this third part may therefore be considered as resembling the explanations of plates which are usually placed at the end of academic memoirs1 that they may not interrupt the connection of the text by lengthened description4 ,though ,i have taken great pains to render this part clear and methodical1 and have not omitted any essential instrument or apparatus1 ,i am far from pretending by it to set aside the necessity of attendance upon lectures and laboratories1 for such as wish to acquire accurate knowledge of the science of chemistry4 ,these should familiarise themselves to the employment of apparatus1 and to the performance of experiments by actual experience4 ,nihil est in intellectu quod non prius fuerit in sensu1 the motto which the celebrated ,rouelle caused to be painted in large characters in a conspicuous part of his laboratory1 is an important truth never to be lost sight of either by teachers or students of chemistry4 ,chemical operations may be naturally divided into several classes1 according to the purposes they are intended for performing4 ,some may be considered as purely mechanical1 such as the determination of the weight and bulk of bodies1 trituration1 levigation1 searching1 washing1 filtration1 c4 ,others may be considered as real chemical operations1 because they are performed by means of chemical powers and agents2 such are solution1 fusion1 c4 ,some of these are intended for separating the elements of bodies from each other1 some for reuniting these elements together2 and some1 as combustion1 produce both these effects during the same process4 ,without rigorously endeavouring to follow the above method1 ,i mean to give a detail of the chemical operations in such order of arrangement as seemed best calculated for conveying instruction4 ,i shall be more particular in describing the apparatus connected with modern chemistry1 because these are hitherto little known by men who have devoted much of their time to chemistry1 and even by many professors of the science4 ,,chap4 ,i4 ,of the ,instruments necessary for determining the ,absolute and ,specific ,gravities of ,solid and ,liquid ,bodies4 ,the best method hitherto known for determining the quantities of substances submitted to chemical experiment1 or resulting from them1 is by means of an accurately constructed beam and scales1 with properly regulated weights1 which well known operation is called weighing4 ,the denomination and quantity of the weights used as an unit or standard for this purpose are extremely arbitrary1 and vary not only in different kingdoms1 but even in different provinces of the same kingdom1 and in different cities of the same province4 ,this variation is of infinite consequence to be well understood in commerce and in the arts2 but1 in chemistry1 it is of no moment what particular denomination of weight be employed1 provided the results of experiments be expressed in convenient fractions of the same denomination4 ,for this purpose1 until all the weights used in society be reduced to the same standard1 it will be sufficient for chemists in different parts to use the common pound of their own country as the unit or standard1 and to express all its fractional parts in decimals1 instead of the arbitrary divisions now in use4 ,by this means the chemists of all countries will be thoroughly understood by each other1 as1 although the absolute weights of the ingredients and products cannot be known1 they will readily1 and without calculation1 be able to determine the relative proportions of these to each other with the utmost accuracy2 so that in this way we shall be possessed of an universal language for this part of chemistry4 ,with this view ,i have long projected to have the pound divided into decimal fractions1 and ,i have of late succeeded through the assistance of ,mr ,fourche balance-maker at ,paris1 who has executed it for me with great accuracy and judgment4 ,i recommend to all who carry on experiments to procure similar divisions of the pound1 which they will find both easy and simple in its application1 with a very small knowledge of decimal fractions#ed4 ,as the usefulness and accuracy of chemistry depends entirely upon the determination of the weights of the ingredients and products both before and after experiments1 too much precision cannot be employed in this part of the subject2 and1 for this purpose1 we must be provided with good instruments4 ,as we are often obliged1 in chemical processes1 to ascertain1 within a grain or less1 the tare or weight of large and heavy instruments1 we must have beams made with peculiar niceness by accurate workmen1 and these must always be kept apart from the laboratory in some place where the vapours of acids1 or other corrosive liquors1 cannot have access1 otherwise the steel will rust1 and the accuracy of the balance be destroyed4 ,i have three sets1 of different sizes1 made by ,mr ,fontin with the utmost nicety1 and1 excepting those made by ,mr ,ramsden of ,london1 ,i do not think any can compare with them for precision and sensibility4 ,the largest of these is about three feet long in the beam for large weights1 up to fifteen or twenty pounds2 the second1 for weights of eighteen or twenty ounces1 is exact to a tenth part of a grain2 and the smallest1 calculated only for weighing about one gros1 is sensibly affected by the five hundredth part of a grain4 ,besides these nicer balances1 which are only used for experiments of research1 we must have others of less value for the ordinary purposes of the laboratory4 ,a large iron balance1 capable of weighing forty or fifty pounds within half a dram1 one of a middle size1 which may ascertain eight or ten pounds1 within ten or twelve grains1 and a small one1 by which about a pound may be determined1 within one grain4 ,we must likewise be provided with weights divided into their several fractions1 both vulgar and decimal1 with the utmost nicety1 and verified by means of repeated and accurate trials in the nicest scales2 and it requires some experience1 and to be accurately acquainted with the different weights1 to be able to use them properly4 ,the best way of precisely ascertaining the weight of any particular substance is to weigh it twice1 once with the decimal divisions of the pound1 and another time with the common subdivisions or vulgar fractions1 and1 by comparing these1 we attain the utmost accuracy4 ,by the specific gravity of any substance is understood the quotient of its absolute weight divided by its magnitude1 or1 what is the same1 the weight of a determinate bulk of any body4 ,the weight of a determinate magnitude of water has been generally assumed as unity for this purpose2 and we express the specific gravity of gold1 sulphuric acid1 c4 by saying1 that gold is nineteen times1 and sulphuric acid twice the weight of water1 and so of other bodies4 ,it is the more convenient to assume water as unity in specific gravities1 that those substances whose specific gravity we wish to determine1 are most commonly weighed in water for that purpose4 ,thus1 if we wish to determine the specific gravity of gold flattened under the hammer1 and supposing the piece of gold to weigh #h oz4 #d gros #b-a_/b grs4 in the air#ee1 it is suspended by means of a fine metallic wire under the scale of a hydrostatic balance1 so as to be entirely immersed in water1 and again weighed4 ,the piece of gold in ,mr ,brisson's experiment lost by this means #c gros #cg grs42 and1 as it is evident that the weight lost by a body weighed in water is precisely equal to the weight of the water displaced1 or to that of an equal volume of water1 we may conclude1 that1 in equal magnitudes1 gold weighs #dhic-a_/b grs4 and water #bec grs4 which1 reduced to unity1 gives #a4jjjj as the specific gravity of water1 and #ai4cfag for that of gold4 ,we may operate in the same manner with all solid substances4 ,we have rarely any occasion1 in chemistry1 to determine the specific gravity of solid bodies1 unless when operating upon alloys or metallic glasses2 but we have very frequent necessity to ascertain that of fluids1 as it is often the only means of judging of their purity or degree of concentration4 ,this object may be very fully accomplished with the hydrostatic balance1 by weighing a solid body2 such1 for example1 as a little ball of rock cristal suspended by a very fine gold wire1 first in the air1 and afterwards in the fluid whose specific gravity we wish to discover4 ,the weight lost by the cristal1 when weighed in the liquor1 is equal to that of an equal bulk of the liquid4 ,by repeating this operation successively in water and different fluids1 we can very readily ascertain1 by a simple and easy calculation1 the relative specific gravities of these fluids1 either with respect to each other or to water4 ,this method is not1 however1 sufficiently exact1 or1 at least1 is rather troublesome1 from its extreme delicacy1 when used for liquids differing but little in specific gravity from water2 such1 for instance1 as mineral waters1 or any other water containing very small portions of salt in solution4 ,in some operations of this nature1 which have not hitherto been made public1 ,i employed an instrument of great sensibility for this purpose with great advantage4 ,it consists of a hollow cylinder1 ,a b c f1 ,pl4 vii4 fig4 #f4 of brass1 or rather of silver1 loaded at its bottom1 b c f1 with tin1 as represented swimming in a jug of water1 l m n o4 ,to the upper part of the cylinder is attached a stalk of silver wire1 not more than three fourths of a line diameter1 surmounted by a little cup d1 intended for containing weights2 upon the stalk a mark is made at g1 the use of which we shall presently explain4 ,this cylinder may be made of any size2 but1 to be accurate1 ought at least to displace four pounds of water4 ,the weight of tin with which this instrument is loaded ought to be such as will make it remain almost in equilibrium in distilled water1 and should not require more than half a dram1 or a dram at most1 to make it sink to g4 ,we must first determine1 with great precision1 the exact weight of the instrument1 and the number of additional grains requisite for making it sink1 in distilled water of a determinate temperature1 to the mark3 ,we then perform the same experiment upon all the fluids of which we wish to ascertain the specific gravity1 and1 by means of calculation1 reduce the observed differences to a common standard of cubic feet1 pints or pounds1 or of decimal fractions1 comparing them with water4 ,this method1 joined to experiments with certain reagents#ef1 is one of the best for determining the quality of waters1 and is even capable of pointing out differences which escape the most accurate chemical analysis4 ,i shall1 at some future period1 give an account of a very extensive set of experiments which ,i have made upon this subject4 ,these metallic hydrometers are only to be used for determining the specific gravities of such waters as contain only neutral salts or alkaline substances2 and they may be constructed with different degrees of ballast for alkohol and other spiritous liquors4 ,when the specific gravities of acid liquors are to be ascertained1 we must use a glass hydrometer1 as represented ,pl4 vii4 fig4 #adeg4 ,this consists of a hollow cylinder of glass1 a b c f1 hermetically sealed at its lower end1 and drawn out at the upper into a capillary tube a1 ending in the little cup or bason d4 ,this instrument is ballasted with more or less mercury1 at the bottom of the cylinder introduced through the tube1 in proportion to the weight of the liquor intended to be examined3 ,we may introduce a small graduated slip of paper into the tube a d2 and1 though these degrees do not exactly correspond to the fractions of grains in the different liquors1 they may be rendered very useful in calculation4 ,what is said in this chapter may suffice1 without farther enlargement1 for indicating the means of ascertaining the absolute and specific gravities of solids and fluids1 as the necessary instruments are generally known1 and may easily be procured3 ,but1 as the instruments ,i have used for measuring the gasses are not any where described1 ,i shall give a more detailed account of these in the following chapter4 ,,footnotes3 #ed ,mr ,lavoisier gives1 in this part of his work1 very accurate directions for reducing the common subdivisions of the ,french pound into decimal fractions1 and vice versa1 by means of tables subjoined to this #c;d part4 ,as these instructions1 and the table1 would be useless to the ,british chemist1 from the difference between the subdivisions of the ,french and ,troy pounds1 ,i have omitted them1 but have subjoined in the appendix accurate rules for converting the one into the other4--,e4 #ee ,vide ,mr ,brisson's ,essay upon ,specific ,gravity1 p4 #e4--;,a4 #ef ,for the use of these reagents see ,bergman's excellent treatise upon the analysis of mineral waters1 in his ,chemical and ,physical ,essays4--,e4 #eg ,three or four years ago1 ,i have seen similar glass hydrometers1 made for ,dr ,black by ,b4 ,knie1 a very ingenious artist of this city4--,e4 ,,chap4 ,,ii4 ,of ,gazometry1 or the ,measurement of the ,weight and ,volume of ,ariform ,substances4 ,,sect4 ,i4 ,description of the ,pneumato-chemical ,apparatus4 ,the ,french chemists have of late applied the name of pneumato-chemical apparatus to the very simple and ingenious contrivance1 invented by ,dr ,priestley1 which is now indispensibly necessary to every laboratory4 ,this consists of a wooden trough1 of larger or smaller dimensions as is thought convenient1 lined with plate-lead or tinned copper1 as represented in perspective1 ,pl4 ,v4 ,in ,fig4 #a4 the same trough or cistern is supposed to have two of its sides cut away1 to show its interior construction more distinctly4 ,in this apparatus1 we distinguish between the shelf ,,abcd ,fig4 #a4 and #b4 and the bottom or body of the cistern ,,fghi ,fig4 #b4 ,the jars or bell-glasses are filled with water in this deep part1 and1 being turned with their mouths downwards1 are afterwards set upon the shelf ,,abcd1 as shown ,plate ,x4 ,fig4 #a4 ,f4 ,the upper parts of the sides of the cistern above the level of the shelf are called the rim or borders4 ,the cistern ought to be filled with water1 so as to stand at least an inch and a half deep upon the shelf1 and it should be of such dimensions as to admit of at least one foot of water in every direction in the well4 ,this size is sufficient for ordinary occasions2 but it is often convenient1 and even necessary1 to have more room2 ,i would therefore advise such as intend to employ themselves usefully in chemical experiments1 to have this apparatus made of considerable magnitude1 where their place of operating will allow4 ,the well of my principal cistern holds four cubical feet of water1 and its shelf has a surface of fourteen square feet2 yet1 in spite of this size1 which ,i at first thought immoderate1 ,i am often straitened for room4 ,in laboratories1 where a considerable number of experiments are performed1 it is necessary to have several lesser cisterns1 besides the large one1 which may be called the general magazine2 and even some portable ones1 which may be moved when necessary1 near a furnace1 or wherever they may be wanted4 ,there are likewise some operations which dirty the water of the apparatus1 and therefore require to be carried on in cisterns by themselves4 ,it were doubtless considerably cheaper to use cisterns1 or iron-bound tubs1 of wood simply dove-tailed1 instead of being lined with lead or copper2 and in my first experiments ,i used them made in that way2 but ,i soon discovered their inconvenience4 ,if the water be not always kept at the same level1 such of the dovetails as are left dry shrink1 and1 when more water is added1 it escapes through the joints1 and runs out4 ,we employ cristal jars or bell glasses1 ,pl4 ,v4 ,fig4 #i4 ,a4 for containing the gasses in this apparatus2 and1 for transporting these1 when full of gas1 from one cistern to another1 or for keeping them in reserve when the cistern is too full1 we make use of a flat dish ,,bc1 surrounded by a standing up rim or border1 with two handles ,,de for carrying it by4 ,after several trials of different materials1 ,i have found marble the best substance for constructing the mercurial pneumato-chemical apparatus1 as it is perfectly impenetrable by mercury1 and is not liable1 like wood1 to separate at the junctures1 or to allow the mercury to escape through chinks2 neither does it run the risk of breaking1 like glass1 stone-ware1 or porcelain4 ,take a block of marble ,,bcde1 ,plate ,v4 ,fig4 #c4 and #d4 about two feet long1 #ae or #ah inches broad1 and ten inches thick1 and cause it to be hollowed out as at m n ,fig4 #e4 about four inches deep1 as a reservoir for the mercury2 and1 to be able more conveniently to fill the jars1 cut the gutter ,t ,v1 ,fig4 #c4 #d4 and #e4 at least four inches deeper2 and1 as this trench may sometimes prove troublesome1 it is made capable of being covered at pleasure by thin boards1 which slip into the grooves x y1 ,fig4 #e4 ,i have two marble cisterns upon this construction1 of different sizes1 by which ,i can always employ one of them as a reservoir of mercury1 which it preserves with more safety than any other vessel1 being neither subject to overturn1 nor to any other accident4 ,we operate with mercury in this apparatus exactly as with water in the one before described2 but the bell-glasses must be of smaller diameter1 and much stronger2 or we may use glass tubes1 having their mouths widened1 as in ,fig4 #g42 these are called eudiometers by the glass-men who sell them4 ,one of the bell-glasses is represented ,fig4 #e4 ,a4 standing in its place1 and what is called a jar is engraved ,fig4 #f4 ,the mercurial pneumato-chemical apparatus is necessary in all experiments wherein the disengaged gasses are capable of being absorbed by water1 as is frequently the case1 especially in all combinations1 excepting those of metals1 in fermentation1 c4 ,,sect4 ,,ii4 ,of the ,gazometer4 ,i give the name of gazometer to an instrument which ,i invented1 and caused construct1 for the purpose of a kind of bellows1 which might furnish an uniform and continued stream of oxygen gas in experiments of fusion4 ,mr ,meusnier and ,i have since made very considerable corrections and additions1 having converted it into what may be called an universal instrument1 without which it is hardly possible to perform most of the very exact experiments4 ,the name we have given the instrument indicates its intention for measuring the volume or quantity of gas submitted to it for examination4 ,it consists of a strong iron beam1 ,,de1 ,pl4 ,,viii4 ,fig4 #a4 three feet long1 having at each end1 ,d and ,e1 a segment of a circle1 likewise strongly constructed of iron1 and very firmly joined4 ,instead of being poised as in ordinary balances1 this beam rests1 by means of a cylindrical axis of polished steel1 ,f1 ,fig4 #i4 upon two large moveable brass friction-wheels1 by which the resistance to its motion from friction is considerably diminished1 being converted into friction of the second order4 ,as an additional precaution1 the parts of these wheels which support the axis of the beam are covered with plates of polished rock-cristal4 ,the whole of this machinery is fixed to the top of the solid column of wood ,,bc1 ,fig4 #a4 ,to one extremity ,d of the beam1 a scale ,p for holding weights is suspended by a flat chain1 which applies to the curvature of the arc n,do1 in a groove made for the purpose4 ,to the other extremity ,e of the beam is applied another flat chain1 i k m1 so constructed1 as to be incapable of lengthening or shortening1 by being less or more charged with weight2 to this chain1 an iron trivet1 with three branches1 a i1 c i1 and h i1 is strongly fixed at i1 and these branches support a large inverted jar ,a1 of hammered copper1 of about #ah inches diameter1 and #bj inches deep4 ,the whole of this machine is represented in perspective1 ,pl4 ,,viii4 ,fig4 #a4 and ,pl4 ,,ix4 ,fig4 #b4 and #d4 give perpendicular sections1 which show its interior structure4 ,round the bottom of the jar1 on its outside1 is fixed 7,pl4 ,,ix4 ,fig4 #b47 a border divided into compartments #a1 #b1 #c1 #d1 c4 intended to receive leaden weights separately represented #a1 #b1 #c1 ,fig4 #c4 ,these are intended for increasing the weight of the jar when a considerable pressure is requisite1 as will be afterwards explained1 though such necessity seldom occurs4 ,the cylindrical jar ,a is entirely open below1 de1 ,pl4 ,,ix4 ,fig4 #d42 but is closed above with a copper lid1 a b c1 open at b f1 and capable of being shut by the cock g4 ,this lid1 as may be seen by inspecting the figures1 is placed a few inches within the top of the jar to prevent the jar from being ever entirely immersed in the water1 and covered over4 ,were ,i to have this instrument made over again1 ,i should cause the lid to be considerably more flattened1 so as to be almost level4 ,this jar or reservoir of air is contained in the cylindrical copper vessel1 ,,lmno1 ,pl4 ,,viii4 ,fig4 #a4 filled with water4 ,in the middle of the cylindrical vessel ,,lmno1 ,pl4 ,,ix4 ,fig4 #d4 are placed two tubes st1 xy1 which are made to approach each other at their upper extremities t y2 these are made of such a length as to rise a little above the upper edge ,,lm of the vessel ,,lmno1 and when the jar abcde touches the bottom ,,no1 their upper ends enter about half an inch into the conical hollow b1 leading to the stop-cock g4 ,the bottom of the vessel ,,lmno is represented ,pl4 ,,ix4 ,fig4 #c4 in the middle of which a small hollow semispherical cap is soldered1 which may be considered as the broad end of a funnel reversed2 the two tubes st1 xy1 ,fig4 #d4 are adapted to this cap at s and x1 and by this means communicate with the tubes mm1 nn1 oo1 pp1 ,fig4 #c4 which are fixed horizontally upon the bottom of the vessel1 and all of which terminate in1 and are united by1 the spherical cap sx4 ,three of these tubes are continued out of the vessel1 as in ,pl4 ,,viii4 ,fig4 #a4 ,the first marked in that figure #a1 #b1 #c1 is inserted at its extremity #c1 by means of an intermediate stop-cock #d1 to the jar ,v4 which stands upon the shelf of a small pneumato-chemical apparatus ,,ghik1 the inside of which is shown ,pl4 ,,ix4 ,fig4 #a4 ,the second tube is applied against the outside of the vessel ,,lmno from #f to #g1 is continued at #h1 #i1 #aj1 and at #aa is engaged below the jar ,v4 ,the former of these tubes is intended for conveying gas into the machine1 and the latter for conducting small quantities for trials under jars4 ,the gas is made either to flow into or out of the machine1 according to the degree of pressure it receives2 and this pressure is varied at pleasure1 by loading the scale ,p less or more1 by means of weights4 ,when gas is to be introduced into the machine1 the pressure is taken off1 or even rendered negative2 but1 when gas is to be expelled1 a pressure is made with such degree of force as is found necessary4 ,the third tube #ab1 #ac1 #ad1 #ae1 is intended for conveying air or gas to any necessary place or apparatus for combustions1 combinations1 or any other experiment in which it is required4 ,to explain the use of the fourth tube1 ,i must enter into some discussions4 ,suppose the vessel ,,lmno1 ,pl4 ,,viii4 ,fig4 #a4 full of water1 and the jar ,a partly filled with gas1 and partly with water2 it is evident that the weights in the bason ,p may be so adjusted1 as to occasion an exact equilibrium between the weight of the bason and of the jar1 so that the external air shall not tend to enter into the jar1 nor the gas to escape from it2 and in this case the water will stand exactly at the same level both within and without the jar4 ,on the contrary1 if the weight in the bason ,p be diminished1 the jar will then press downwards from its own gravity1 and the water will stand lower within the jar than it does without2 in this case1 the included air or gas will suffer a degree of compression above that experienced by the external air1 exactly proportioned to the weight of a column of water1 equal to the difference of the external and internal surfaces of the water4 ,from these reflections1 ,mr ,meusnier contrived a method of determining the exact degree of pressure to which the gas contained in the jar is at any time exposed4 ,for this purpose1 he employs a double glass syphon #ai1 #bj1 #ba1 #bb1 #bc1 firmly cemented at #ai and #bc4 ,the extremity #ai of this syphon communicates freely with the water in the external vessel of the machine1 and the extremity #bc communicates with the fourth tube at the bottom of the cylindrical vessel1 and consequently1 by means of the perpendicular tube st1 ,pl4 ,,ix4 ,fig4 #d4 with the air contained in the jar4 ,he likewise cements1 at #af1 ,pl4 ,,viii4 ,fig4 #a4 another glass tube #af1 #ag1 #ah1 which communicates at #af with the water in the exterior vessel ,,lmno1 and1 at its upper end #ah1 is open to the external air4 ,by these several contrivances1 it is evident that the water must stand in the tube #af1 #ag1 #ah1 at the same level with that in the cistern ,,lmno2 and1 on the contrary1 that1 in the branch #ai1 #bj1 #ba1 it must stand higher or lower1 according as the air in the jar is subjected to a greater or lesser pressure than the external air4 ,to ascertain these differences1 a brass scale divided into inches and lines is fixed between these two tubes4 ,it is readily conceived that1 as air1 and all other elastic fluids1 must increase in weight by compression1 it is necessary to know their degree of condensation to be enabled to calculate their quantities1 and to convert the measure of their volumes into correspondent weights2 and this object is intended to be fulfilled by the contrivance now described4 ,but1 to determine the specific gravity of air or of gasses1 and to ascertain their weight in a known volume1 it is necessary to know their temperature1 as well as the degree of pressure under which they subsist2 and this is accomplished by means of a small thermometer1 strongly cemented into a brass collet1 which screws into the lid of the jar ,a4 ,this thermometer is represented separately1 ,pl4 ,,viii4 ,fig4 #aj4 and in its place #bd1 #be1 ,fig4 #a4 and ,pl4 ,,ix4 ,fig4 #d4 ,the bulb is in the inside of the jar ,a1 and its graduated stalk rises on the outside of the lid4 ,the practice of gazometry would still have laboured under great difficulties1 without farther precautions than those above described4 ,when the jar ,a sinks in the water of the cistern ,,lmno1 it must lose a weight equal to that of the water which it displaces2 and consequently the compression which it makes upon the contained air or gas must be proportionally diminished4 ,hence the gas furnished1 during experiments from the machine1 will not have the same density towards the end that it had at the beginning1 as its specific gravity is continually diminishing4 ,this difference may1 it is true1 be determined by calculation2 but this would have occasioned such mathematical investigations as must have rendered the use of this apparatus both troublesome and difficult4 ,mr ,meusnier has remedied this inconvenience by the following contrivance4 ,a square rod of iron1 #bf1 #bg1 ,pl4 ,,viii4 ,fig4 #a4 is raised perpendicular to the middle of the beam ,,de4 ,this rod passes through a hollow box of brass #bh1 which opens1 and may be filled with lead2 and this box is made to slide alongst the rod1 by means of a toothed pinion playing in a rack1 so as to raise or lower the box1 and to fix it at such places as is judged proper4 ,when the lever or beam ,,de stands horizontal1 this box gravitates to neither side2 but1 when the jar ,a sinks into the cistern ,,lmno1 so as to make the beam incline to that side1 it is evident the loaded box #bh1 which then passes beyond the center of suspension1 must gravitate to the side of the jar1 and augment its pressure upon the included air4 ,this is increased in proportion as the box is raised towards #bg1 because the same weight exerts a greater power in proportion to the length of the lever by which it acts4 ,hence1 by moving the box #bh alongst the rod #bf1 #bg1 we can augment or diminish the correction it is intended to make upon the pressure of the jar2 and both experience and calculation show that this may be made to compensate very exactly for the loss of weight in the jar at all degrees of pressure4 ,i have not hitherto explained the most important part of the use of this machine1 which is the manner of employing it for ascertaining the quantities of the air or gas furnished during experiments4 ,to determine this with the most rigorous precision1 and likewise the quantity supplied to the machine from experiments1 we fixed to the arc which terminates the arm of the beam ,e1 ,pl4 ,,viii4 ,fig4 #a4 the brass sector l m1 divided into degrees and half degrees1 which consequently moves in common with the beam2 and the lowering of this end of the beam is measured by the fixed index #bi1 #cj1 which has a ,nonius giving hundredth parts of a degree at its extremity #cj4 ,the whole particulars of the different parts of the above described machine are represented in ,plate ,,viii4 as follow4 ,fig4 #b4 ,is the flat chain invented by ,mr ,vaucanson1 and employed for suspending the scale or bason ,p1 ,fig4 #a2 but1 as this lengthens or shortens according as it is more or less loaded1 it would not have answered for suspending the jar ,a1 ,fig4 #a4 ,fig4 #e4 ,is the chain i k m1 which in ,fig4 #a4 sustains the jar ,a4 ,this is entirely formed of plates of polished iron interlaced into each other1 and held together by iron pins4 ,this chain does not lengthen in any sensible degree1 by any weight it is capable of supporting4 ,fig4 #f4 ,the trivet1 or three branched stirrup1 by which the jar ,a is hung to the balance1 with the screw by which it is fixed in an accurately vertical position4 ,fig4 #c4 ,the iron rod #bf1 #bg1 which is fixed perpendicular to the center of the beam1 with its box #bh4 ,fig4 #g4 #h4 ,the friction-wheels1 with the plates of rock-cristal ,z1 as points of contact by which the friction of the axis of the lever of the balance is avoided4 ,fig4 #d4 ,the piece of metal which supports the axis of the friction-wheels4 ,fig4 #i4 ,the middle of the lever or beam1 with the axis upon which it moves4 ,fig4 #aj4 ,the thermometer for determining the temperature of the air or gas contained in the jar4 ,when this gazometer is to be used1 the cistern or external vessel1 ,,lmno1 ,pl4 ,,viii4 ,fig4 #a4 is to be filled with water to a determinate height1 which should be the same in all experiments4 ,the level of the water should be taken when the beam of the balance stands horizontal2 this level1 when the jar is at the bottom of the cistern1 is increased by all the water which it displaces1 and is diminished in proportion as the jar rises to its highest elevation4 ,we next endeavour1 by repeated trials1 to discover at what elevation the box #bh must be fixed1 to render the pressure equal in all situations of the beam4 ,i should have said nearly1 because this correction is not absolutely rigorous2 and differences of a quarter1 or even of half a line1 are not of any consequence4 ,this height of the box #bh is not the same for every degree of pressure1 but varies according as this is of one1 two1 three1 or more inches4 ,all these should be registered with great order and precision4 ,we next take a bottle which holds eight or ten pints1 the capacity of which is very accurately determined by weighing the water it is capable of containing4 ,this bottle is turned bottom upwards1 full of water1 in the cistern of the pneumato chemical apparatus ,,ghik1 ,fig4 #a4 and is set on its mouth upon the shelf of the apparatus1 instead of the glass jar ,v1 having the extremity #aa of the tube #g1 #h1 #i1 #aj1 #aa1 inserted into its mouth4 ,the machine is fixed at zero of pressure1 and the degree marked by the index #cj upon the sector m l is accurately observed2 then1 by opening the stop-cock #h1 and pressing a little upon the jar ,a1 as much air is forced into the bottle as fills it entirely4 ,the degree marked by the index upon the sector is now observed1 and we calculate what number of cubical inches correspond to each degree4 ,we then fill a second and third bottle1 and so on1 in the same manner1 with the same precautions1 and even repeat the operation several times with bottles of different sizes1 till at last1 by accurate attention1 we ascertain the exact gage or capacity of the jar ,a1 in all its parts2 but it is better to have it formed at first accurately cylindrical1 by which we avoid these calculations and estimates4 ,the instrument ,i have been describing was constructed with great accuracy and uncommon skill by ,mr ,meignie junior1 engineer and physical instrument-maker4 ,it is a most valuable instrument1 from the great number of purposes to which it is applicable2 and1 indeed1 there are many experiments which are almost impossible to be performed without it4 ,it becomes expensive1 because1 in many experiments1 such as the formation of water and of nitric acid1 it is absolutely necessary to employ two of the same machines4 ,in the present advanced state of chemistry1 very expensive and complicated instruments are become indispensibly necessary for ascertaining the analysis and synthesis of bodies with the requisite precision as to quantity and proportion2 it is certainly proper to endeavour to simplify these1 and to render them less costly2 but this ought by no means to be attempted at the expence of their conveniency of application1 and much less of their accuracy4 ,,sect4 ,,iii4 ,some other methods of measuring the volume of ,gasses4 ,the gazometer described in the foregoing section is too costly and too complicated for being generally used in laboratories for measuring the gasses1 and is not even applicable to every circumstance of this kind4 ,in numerous series of experiments1 more simple and more readily applicable methods must be employed4 ,for this purpose ,i shall describe the means ,i used before ,i was in possession of a gazometer1 and which ,i still use in preference to it in the ordinary course of my experiments4 ,suppose that1 after an experiment1 there is a residuum of gas1 neither absorbable by alkali nor water1 contained in the upper part of the jar ,,aef1 ,pl4 ,,iv4 ,fig4 #c4 standing on the shelf of a pneumato-chemical apparatus1 of which we wish to ascertain the quantity1 we must first mark the height to which the mercury or water rises in the jar with great exactness1 by means of slips of paper pasted in several parts round the jar4 ,if we have been operating in mercury1 we begin by displacing the mercury from the jar1 by introducing water in its stead4 ,this is readily done by filling a bottle quite full of water2 having stopped it with your finger1 turn it up1 and introduce its mouth below the edge of the jar2 then1 turning down its body again1 the mercury1 by its gravity1 falls into the bottle1 and the water rises in the jar1 and takes the place occupied by the mercury4 ,when this is accomplished1 pour so much water into the cistern ,,abcd as will stand about an inch over the surface of the mercury2 then pass the dish ,,bc1 ,pl4 ,v4 ,fig4 #i4 under the jar1 and carry it to the water cistern1 ,fig4 #a4 and #b4 ,we here exchange the gas into another jar1 which has been previously graduated in the manner to be afterwards described2 and we thus judge of the quantity or volume of the gas by means of the degrees which it occupies in the graduated jar4 ,there is another method of determining the volume of gas1 which may either be substituted in place of the one above described1 or may be usefully employed as a correction or proof of that method4 ,after the air or gas is exchanged from the first jar1 marked with slips of paper1 into the graduated jar1 turn up the mouth of the marked jar1 and fill it with water exactly to the marks ,,ef1 ,pl4 ,,iv4 ,fig4 #c4 and by weighing the water we determine the volume of the air or gas it contained1 allowing one cubical foot1 or #agbh cubical inches1 of water for each #gj pounds1 ,french weight4 ,the manner of graduating jars for this purpose is very easy1 and we ought to be provided with several of different sizes1 and even several of each size1 in case of accidents4 ,take a tall1 narrow1 and strong glass jar1 and1 having filled it with water in the cistern1 ,pl4 ,v4 ,fig4 #a4 place it upon the shelf ,,abcd2 we ought always to use the same place for this operation1 that the level of the shelf may be always exactly similar1 by which almost the only error to which this process is liable will be avoided4 ,then take a narrow mouthed phial which holds exactly #f oz4 #c gros #fa grs4 of water1 which corresponds to #aj cubical inches4 ,if you have not one exactly of this dimension1 choose one a little larger1 and diminish its capacity to the size requisite1 by dropping in a little melted wax and rosin4 ,this bottle serves the purpose of a standard for gaging the jars4 ,make the air contained in this bottle pass into the jar1 and mark exactly the place to which the water has descended2 add another measure of air1 and again mark the place of the water1 and so on1 till all the water be displaced4 ,it is of great consequence that1 during the course of this operation1 the bottle and jar be kept at the same temperature with the water in the cistern2 and1 for this reason1 we must avoid keeping the hands upon either as much as possible2 or1 if we suspect they have been heated1 we must cool them by means of the water in the cistern4 ,the height of the barometer and thermometer during this experiment is of no consequence4 ,when the marks have been thus ascertained upon the jar for every ten cubical inches1 we engrave a scale upon one of its sides1 by means of a diamond pencil4 ,glass tubes are graduated in the same manner for using in the mercurial apparatus1 only they must be divided into cubical inches1 and tenths of a cubical inch4 ,the bottle used for gaging these must hold #h oz4 #f gros #be grs4 of mercury1 which exactly corresponds to a cubical inch of that metal4 ,the method of determining the volume of air or gas1 by means of a graduated jar1 has the advantage of not requiring any correction for the difference of height between the surface of the water within the jar1 and in the cistern2 but it requires corrections with respect to the height of the barometer and thermometer4 ,but1 when we ascertain the volume of air by weighing the water which the jar is capable of containing1 up to the marks ,,ef1 it is necessary to make a farther correction1 for the difference between the surface of the water in the cistern1 and the height to which it rises within the jar4 ,this will be explained in the fifth section of this chapter4 ,,sect4 ,,iv4 ,of the method of ,separating the different ,gasses from each other4 ,as experiments often produce two1 three1 or more species of gas1 it is necessary to be able to separate these from each other1 that we may ascertain the quantity and species of each4 ,suppose that under the jar ,a1 ,pl4 ,,iv4 ,fig4 #c4 is contained a quantity of different gasses mixed together1 and standing over mercury1 we begin by marking with slips of paper1 as before directed1 the height at which the mercury stands within the glass2 then introduce about a cubical inch of water into the jar1 which will swim over the surface of the mercury3 ,if the mixture of gas contains any muriatic or sulphurous acid gas1 a rapid and considerable absorption will instantly take place1 from the strong tendency these two gasses have1 especially the former1 to combine with1 or be absorbed by water4 ,if the water only produces a slight absorption of gas hardly equal to its own bulk1 we conclude1 that the mixture neither contains muriatic acid1 sulphuric acid1 or ammoniacal gas1 but that it contains carbonic acid gas1 of which water only absorbs about its own bulk4 ,to ascertain this conjecture1 introduce some solution of caustic alkali1 and the carbonic acid gas will be gradually absorbed in the course of a few hours2 it combines with the caustic alkali or potash1 and the remaining gas is left almost perfectly free from any sensible residuum of carbonic acid gas4 ,after each experiment of this kind1 we must carefully mark the height at which the mercury stands within the jar1 by slips of paper pasted on1 and varnished over when dry1 that they may not be washed off when placed in the water apparatus4 ,it is likewise necessary to register the difference between the surface of the mercury in the cistern and that in the jar1 and the height of the barometer and thermometer1 at the end of each experiment4 ,when all the gas or gasses absorbable by water and potash are absorbed1 water is admitted into the jar to displace the mercury2 and1 as is described in the preceding section1 the mercury in the cistern is to be covered by one or two inches of water4 ,after this1 the jar is to be transported by means of the flat dish ,,bc1 ,pl4 ,v4 ,fig4 #i4 into the water apparatus2 and the quantity of gas remaining is to be ascertained by changing it into a graduated jar4 ,after this1 small trials of it are to be made by experiments in little jars1 to ascertain nearly the nature of the gas in question4 ,for instance1 into a small jar full of the gas1 ,fig4 #h4 ,pl4 ,v4 a lighted taper is introduced2 if the taper is not immediately extinguished1 we conclude the gas to contain oxygen gas2 and1 in proportion to the brightness of the flame1 we may judge if it contain less or more oxygen gas than atmospheric air contains4 ,if1 on the contrary1 the taper be instantly extinguished1 we have strong reason to presume that the residuum is chiefly composed of azotic gas4 ,if1 upon the approach of the taper1 the gas takes fire and burns quietly at the surface with a white flame1 we conclude it to be pure hydrogen gas2 if this flame is blue1 we judge it consists of carbonated hydrogen gas2 and1 if it takes fire with a sudden deflagration1 that it is a mixture of oxygen and hydrogen gas4 ,if1 again1 upon mixing a portion of the residuum with oxygen gas1 red fumes are produced1 we conclude that it contains nitrous gas4 ,these preliminary trials give some general knowledge of the properties of the gas1 and nature of the mixture1 but are not sufficient to determine the proportions and quantities of the several gasses of which it is composed4 ,for this purpose all the methods of analysis must be employed2 and1 to direct these properly1 it is of great use to have a previous approximation by the above methods4 ,suppose1 for instance1 we know that the residuum consists of oxygen and azotic gas mixed together1 put a determinate quantity1 #ajj parts1 into a graduated tube of ten or twelve lines diameter1 introduce a solution of sulphuret of potash in contact with the gas1 and leave them together for some days2 the sulphuret absorbs the whole oxygen gas1 and leaves the azotic gas pure4 ,if it is known to contain hydrogen gas1 a determinate quantity is introduced into ,volta's eudiometer alongst with a known proportion of hydrogen gas2 these are deflagrated together by means of the electrical spark2 fresh portions of oxygen gas are successively added1 till no farther deflagration takes place1 and till the greatest possible diminution is produced4 ,by this process water is formed1 which is immediately absorbed by the water of the apparatus2 but1 if the hydrogen gas contain charcoal1 carbonic acid is formed at the same time1 which is not absorbed so quickly2 the quantity of this is readily ascertained by assisting its absorption1 by means of agitation4 ,if the residuum contains nitrous gas1 by adding oxygen gas1 with which it combines into nitric acid1 we can very nearly ascertain its quantity1 from the diminution produced by this mixture4 ,i confine myself to these general examples1 which are sufficient to give an idea of this kind of operations2 a whole volume would not serve to explain every possible case4 ,it is necessary to become familiar with the analysis of gasses by long experience2 we must even acknowledge that they mostly possess such powerful affinities to each other1 that we are not always certain of having separated them completely4 ,in these cases1 we must vary our experiments in every possible point of view1 add new agents to the combination1 and keep out others1 and continue our trials1 till we are certain of the truth and exactitude of our conclusions4 ,,sect4 ,v4 ,of the necessary corrections upon the volume of the ,gasses1 according to the pressure of the ,atmosphere4 ,all elastic fluids are compressible or condensible in proportion to the weight with which they are loaded4 ,perhaps this law1 which is ascertained by general experience1 may suffer some irregularity when these fluids are under a degree of condensation almost sufficient to reduce them to the liquid state1 or when either in a state of extreme rarefaction or condensation2 but we seldom approach either of these limits with most of the gasses which we submit to our experiments4 ,i understand this proposition of gasses being compressible1 in proportion to their superincumbent weights1 as follows3 ,a barometer1 which is an instrument generally known1 is1 properly speaking1 a species of syphon1 ,,abcd1 ,pl4 ,,xii4 ,fig4 #af4 whose leg ,,ab is filled with mercury1 whilst the leg ,,cd is full of air4 ,if we suppose the branch ,,cd indefinitely continued till it equals the height of our atmosphere1 we can readily conceive that the barometer is1 in reality1 a sort of balance1 in which a column of mercury stands in equilibrium with a column of air of the same weight4 ,but it is unnecessary to prolongate the branch ,,cd to such a height1 as it is evident that the barometer being immersed in air1 the column of mercury ,,ab will be equally in equilibrium with a column of air of the same diameter1 though the leg ,,cd be cut off at ,c1 and the part ,,cd be taken away altogether4 ,the medium height of mercury in equilibrium with the weight of a column of air1 from the highest part of the atmosphere to the surface of the earth is about twenty-eight ,french inches in the lower parts of the city of ,paris2 or1 in other words1 the air at the surface of the earth at ,paris is usually pressed upon by a weight equal to that of a column of mercury twenty-eight inches in height4 ,i must be understood in this way in the several parts of this publication when talking of the different gasses1 as1 for instance1 when the cubical foot of oxygen gas is said to weigh #a oz4 #d gros1 under #bh inches pressure4 ,the height of this column of mercury1 supported by the pressure of the air1 diminishes in proportion as we are elevated above the surface of the earth1 or rather above the level of the sea1 because the mercury can only form an equilibrium with the column of air which is above it1 and is not in the smallest degree affected by the air which is below its level4 ,in what ratio does the mercury in the barometer descend in proportion to its elevation8 or1 what is the same thing1 according to what law or ratio do the several strata of the atmosphere decrease in density8 ,this question1 which has exercised the ingenuity of natural philosophers during last century1 is considerably elucidated by the following experiment4 ,if we take the glass syphon ,,abcde1 ,pl4 ,,xii4 ,fig4 #ag4 shut at ,e1 and open at ,a1 and introduce a few drops of mercury1 so as to intercept the communication of air between the leg ,,ab and the leg ,,be1 it is evident that the air contained in ,,bcde is pressed upon1 in common with the whole surrounding air1 by a weight or column of air equal to #bh inches of mercury4 ,but1 if we pour #bh inches of mercury into the leg ,,ab1 it is plain the air in the branch ,,bcde will now be pressed upon by a weight equal to twice #bh inches of mercury1 or twice the weight of the atmosphere2 and experience shows1 that1 in this case1 the included air1 instead of filling the tube from ,b to ,e1 only occupies from ,c to ,e1 or exactly one half of the space it filled before4 ,if to this first column of mercury we add two other portions of #bh inches each1 in the branch ,,ab1 the air in the branch ,,bcde will be pressed upon by four times the weight of the atmosphere1 or four times the weight of #bh inches of mercury1 and it will then only fill the space from ,d to ,e1 or exactly one quarter of the space it occupied at the commencement of the experiment4 ,from these experiments1 which may be infinitely varied1 has been deduced as a general law of nature1 which seems applicable to all permanently elastic fluids1 that they diminish in volume in proportion to the weights with which they are pressed upon2 or1 in other words1 the volume of all elastic fluids is in the inverse ratio of the weight by which they are compressed4 ,the experiments which have been made for measuring the heights of mountains by means of the barometer1 confirm the truth of these deductions2 and1 even supposing them in some degree inaccurate1 these differences are so extremely small1 that they may be reckoned as nullities in chemical experiments4 ,when this law of the compression of elastic fluids is once well understood1 it becomes easily applicable to the corrections necessary in pneumato chemical experiments upon the volume of gas1 in relation to its pressure4 ,these corrections are of two kinds1 the one relative to the variations of the barometer1 and the other for the column of water or mercury contained in the jars4 ,i shall endeavour to explain these by examples1 beginning with the most simple case4 ,suppose that #ajj cubical inches of oxygen gas are obtained at #aj 7#ed4e7 of the thermometer1 and at #bh inches #f lines of the barometer1 it is required to know what volume the #ajj cubical inches of gas would occupy1 under the pressure of #bh inches#eh1 and what is the exact weight of the #ajj inches of oxygen gas8 ,let the unknown volume1 or the number of inches this gas would occupy at #bh inches of the barometer1 be expressed by x2 and1 since the volumes are in the inverse ratio of their superincumbent weights1 we have the following statement3 #ajj cubical inches is to x inversely as #bh4e inches of pressure is to #bh4j inches2 or directly #bh 3 #bh4e 33 #ajj 3 x #aja4ghf--;cubical inches1 at #bh inches barometrical pressure2 that is to say1 the same gas or air which at #bh4e inches of the barometer occupies #ajj cubical inches of volume1 will occupy #aja4ghf cubical inches when the barometer is at #bh inches4 ,it is equally easy to calculate the weight of this gas1 occupying #ajj cubical inches1 under #bh4e inches of barometrical pressure2 for1 as it corresponds to #aja4ghf cubical inches at the pressure of #bh1 and as1 at this pressure1 and at #aj 7#ed4e7 of temperature1 each cubical inch of oxygen gas weighs half a grain1 it follows1 that #ajj cubical inches1 under #bh4e barometrical pressure1 must weigh #ej4hic grains4 ,this conclusion might have been formed more directly1 as1 since the volume of elastic fluids is in the inverse ratio of their compression1 their weights must be in the direct ratio of the same compression3 ,hence1 since #ajj cubical inches weigh #ej grains1 under the pressure of #bh inches1 we have the following statement to determine the weight of #ajj cubical inches of the same gas as #bh4e barometrical pressure1 #bh 3 #ej 33 #bh4e 3 x1 the unknown quantity1 #ej4hic4 ,the following case is more complicated3 ,suppose the jar ,a1 ,pl4 ,,xii4 ,fig4 #ah4 to contain a quantity of gas in its upper part ,,acd1 the rest of the jar below ,,cd being full of mercury1 and the whole standing in the mercurial bason or reservoir ,,ghik1 filled with mercury up to ,,ef1 and that the difference between the surface ,,cd of the mercury in the jar1 and ,,ef1 that in the cistern1 is six inches1 while the barometer stands at #bg4e inches4 ,it is evident from these data1 that the air contained in ,,acd is pressed upon by the weight of the atmosphere1 diminished by the weight of the column of mercury ,,ce1 or by #bg4e - #f #ba4e inches of barometrical pressure4 ,this air is therefore less compressed than the atmosphere at the mean height of the barometer1 and consequently occupies more space than it would occupy at the mean pressure1 the difference being exactly proportional to the difference between the compressing weights4 ,if1 then1 upon measuring the space ,,acd1 it is found to be #abj cubical inches1 it must be reduced to the volume which it would occupy under the mean pressure of #bh inches4 ,this is done by the following statement3 #abj 3 x1 the unknown volume1 33 #ba4e 3 #bh inversely2 this gives x #abj #ba4e _/ #bh #ib4adc cubical inches4 ,in these calculations we may either reduce the height of the mercury in the barometer1 and the difference of level in the jar and bason1 into lines or decimal fractions of the inch2 but ,i prefer the latter1 as it is more readily calculated4 ,as1 in these operations1 which frequently recur1 it is of great use to have means of abbreviation1 ,i have given a table in the appendix for reducing lines and fractions of lines into decimal fractions of the inch4 ,in experiments performed in the water-apparatus1 we must make similar corrections to procure rigorously exact results1 by taking into account1 and making allowances for the difference of height of the water within the jar above the surface of the water in the cistern4 ,but1 as the pressure of the atmosphere is expressed in inches and lines of the mercurial barometer1 and1 as homogeneous quantities only can be calculated together1 we must reduce the observed inches and lines of water into correspondent heights of the mercury4 ,i have given a table in the appendix for this conversion1 upon the supposition that mercury is #ac4efha times heavier than water4 ,,sect4 ,,vi4 ,of ,corrections relative to the ,degrees of the ,thermometer4 ,in ascertaining the weight of gasses1 besides reducing them to a mean of barometrical pressure1 as directed in the preceding section1 we must likewise reduce them to a standard thermometrical temperature2 because1 all elastic fluids being expanded by heat1 and condensed by cold1 their weight in any determinate volume is thereby liable to considerable alterations4 ,as the temperature of #aj 7#ed4e7 is a medium between the heat of summer and the cold of winter1 being the temperature of subterraneous places1 and that which is most easily approached to at all seasons1 ,i have chosen that degree as a mean to which ,i reduce air or gas in this species of calculation4 ,mr de ,luc found that atmospheric air was increased #a_/bae part of its bulk1 by each degree of a mercurial thermometer1 divided into #ha degrees1 between the freezing and boiling points2 this gives #a_/baa part for each degree of ,reaumur's thermometer1 which is divided into #hj degrees between these two points4 ,the experiments of ,mr ,monge seem to make this dilatation less for hydrogen gas1 which he thinks is only dilated #a_/ahj4 ,we have not any exact experiments hitherto published respecting the ratio of dilatation of the other gasses2 but1 from the trials which have been made1 their dilatation seems to differ little from that of atmospheric air4 ,hence ,i may take for granted1 till farther experiments give us better information upon this subject1 that atmospherical air is dilated #a_/baj part1 and hydrogen gas #a_/aij part for each degree of the thermometer2 but1 as there is still great uncertainty upon this point1 we ought always to operate in a temperature as near as possible to the standard of #aj1 7#ed4e7 by this means any errors in correcting the weight or volume of gasses by reducing them to the common standard1 will become of little moment4 ,the calculation for this correction is extremely easy4 ,divide the observed volume of air by #baj1 and multiply the quotient by the degrees of temperature above or below #aj 7#ed4e74 ,this correction is negative when the actual temperature is above the standard1 and positive when below4 ,by the use of logarithmical tables this calculation is much facilitated#ei4 ,,sect4 ,,vii4 ,example for calculating the ,corrections relative to the ,variations of ,pressure and ,temperature4 ,,case4 ,in the jar ,a1 ,pl4 ,,iv4 ,fig4 #c4 standing in a water apparatus1 is contained #cec cubical inches of air2 the surface of the water within the jar at ,,ef is #d-a_/b inches above the water in the cistern1 the barometer is at #bg inches #i-a_/b lines1 and the thermometer at #ae 7#fe4ge74 ,having burnt a quantity of phosphorus in the air1 by which concrete phosphoric acid is produced1 the air after the combustion occupies #bie cubical inches1 the water within the jar stands #g inches above that in the cistern1 the barometer is at #bg inches #i-a_/d lines1 and the thermometer at #af 7#fh74 ,it is required from these data to determine the actual volume of air before and after combustion1 and the quantity absorbed during the process4 ,calculation before ,combustion4 ,the air in the jar before combustion was #cec cubical inches1 but it was only under a barometrical pressure of #bg inches #i-a_/b lines2 which1 reduced to decimal fractions by ,tab4 ,i4 of the ,appendix1 gives #bg4giafg inches2 and from this we must deduct the difference of #d-a_/b inches of water1 which1 by ,tab4 ,,ii4 corresponds to #j4ccaff inches of the barometer2 hence the real pressure of the air in the jar is #bg4dfjja4 ,as the volume of elastic fluids diminish in the inverse ratio of the compressing weights1 we have the following statement to reduce the #cec inches to the volume the air would occupy at #bh inches barometrical pressure4 #cec 3 x1 the unknown volume1 33 #bg4dfjja 3 #bh4 ,hence1 x #cec #bg4dfjja _/ #bh #cdf4aib cubical inches1 which is the volume the same quantity of air would have occupied at #bh inches of the barometer4 ,the #bajth part of this corrected volume is #a4fe1 which1 for the five degrees of temperature above the standard gives #h4bee cubical inches2 and1 as this correction is subtractive1 the real corrected volume of the air before combustion is #ccg4idb inches4 ,calculation after ,combustion4 ,by a similar calculation upon the volume of air after combustion1 we find its barometrical pressure #bg4ggjhc - #j4eaeic #bg4bedij4 ,hence1 to have the volume of air under the pressure of #bh inches1 #bie 3 x 33 #bg4ggjhc 3 #bh inversely2 or1 x #bie x #bg4bedij _/ #bh #bhg4aej4 ,the #bajth part of this corrected volume is #a4cfh1 which1 multiplied by #f degrees of thermometrical difference1 gives the subtractive correction for temperature #h4bjh1 leaving the actual corrected volume of air after combustion #bgh4idb inches4 ,result4 ,the corrected volume before combustion #ccg4idb ,ditto remaining after combustion #bgh4idb -------- ,volume absorbed during combustion #ei4jjj4 ,,sect4 ,,viii4 ,method of determining the ,absolute ,gravity of the different ,gasses4 ,take a large balloon ,a1 ,pl4 ,v4 ,fig4 #aj4 capable of holding #ag or #ah pints1 or about half a cubical foot1 having the brass cap bcde strongly cemented to its neck1 and to which the tube and stop-cock f g is fixed by a tight screw4 ,this apparatus is connected by the double screw represented separately at ,fig4 #ab4 to the jar ,,bcd1 ,fig4 #aj4 which must be some pints larger in dimensions than the balloon4 ,this jar is open at top1 and is furnished with the brass cap h i1 and stop-cock l m4 ,one of these slop-cocks is represented separately at ,fig4 #aa4 ,we first determine the exact capacity of the balloon by filling it with water1 and weighing it both full and empty4 ,when emptied of water1 it is dried with a cloth introduced through its neck d e1 and the last remains of moisture are removed by exhausting it once or twice in an air-pump4 ,when the weight of any gas is to be ascertained1 this apparatus is used as follows3 ,fix the balloon ,a to the plate of an air-pump by means of the screw of the stop-cock f g1 which is left open2 the balloon is to be exhausted as completely as possible1 observing carefully the degree of exhaustion by means of the barometer attached to the air-pump4 ,when the vacuum is formed1 the stop-cock f g is shut1 and the weight of the balloon determined with the most scrupulous exactitude4 ,it is then fixed to the jar ,,bcd1 which we suppose placed in water in the shelf of the pneumato chemical apparatus ,fig4 #a42 the jar is to be filled with the gas we mean to weigh1 and then1 by opening the stop-cocks f g and l m1 the gas ascends into the balloon1 whilst the water of the cistern rises at the same time into the jar4 ,to avoid very troublesome corrections1 it is necessary1 during this first part of the operation1 to sink the jar in the cistern till the surfaces of the water within the jar and without exactly correspond4 ,the stop-cocks are again shut1 and the balloon being unscrewed from its connection with the jar1 is to be carefully weighed2 the difference between this weight and that of the exhausted balloon is the precise weight of the air or gas contained in the balloon4 ,multiply this weight by #agbh1 the number of cubical inches in a cubical foot1 and divide the product by the number of cubical inches contained in the balloon1 the quotient is the weight of a cubical foot of the gas or air submitted to experiment4 ,exact account must be kept of the barometrical height and temperature of the thermometer during the above experiment2 and from these the resulting weight of a cubical foot is easily corrected to the standard of #bh inches and #aj1 as directed in the preceding section4 ,the small portion of air remaining in the balloon after forming the vacuum must likewise be attended to1 which is easily determined by the barometer attached to the air-pump4 ,if that barometer1 for instance1 remains at the hundredth part of the height it stood at before the vacuum was formed1 we conclude that one hundredth part of the air originally contained remained in the balloon1 and consequently that only #ii_/ajj of gas was introduced from the jar into the balloon4 ,,footnotes3 #eh ,according to the proportion of #aad to #ajg1 given between the ,french and ,english foot1 #bh inches of the ,french barometer are equal to #bi4hc inches of the ,english4 ,directions will be found in the appendix for converting all the ,french weights and measures used in this work into corresponding ,english denominations4--,e4 #ei ,when ,fahrenheit's thermometer is employed1 the dilatation by each degree must be smaller1 in the proportion of #a to #b4be1 because each degree of ,reaumur's scale contains #b4be degrees of ,fahrenheit2 hence we must divide by #dgb4e1 and finish the rest of the calculation as above4--,e4 ,,chap4 ,,iii4 ,description of the ,calorimeter1 or ,apparatus for measuring ,caloric4 ,the calorimeter1 or apparatus for measuring the relative quantities of heat contained in bodies1 was described by ,mr de la ,place and me in the ,memoirs of the ,academy for #aghj1 p4 #cee4 and from that ,essay the materials of this chapter are extracted4 ,if1 after having cooled any body to the freezing point1 it be exposed in an atmosphere of #be 7#hh4be71 the body will gradually become heated1 from the surface inwards1 till at last it acquire the same temperature with the surrounding air4 ,but1 if a piece of ice be placed in the same situation1 the circumstances are quite different2 it does not approach in the smallest degree towards the temperature of the circumambient air1 but remains constantly at ,zero 7#cb71 or the temperature of melting ice1 till the last portion of ice be completely melted4 ,this phenomenon is readily explained2 as1 to melt ice1 or reduce it to water1 it requires to be combined with a certain portion of caloric2 the whole caloric attracted from the surrounding bodies1 is arrested or fixed at the surface or external layer of ice which it is employed to dissolve1 and combines with it to form water2 the next quantity of caloric combines with the second layer to dissolve it into water1 and so on successively till the whole ice be dissolved or converted into water by combination with caloric1 the very last atom still remaining at its former temperature1 because the caloric has never penetrated so far as long as any intermediate ice remained to melt4 ,upon these principles1 if we conceive a hollow sphere of ice at the temperature of ,zero 7#cb7 placed in an atmosphere #aj 7#ed4e71 and containing a substance at any degree of temperature above freezing1 it follows1 #ast1 ,that the heat of the external atmosphere cannot penetrate into the internal hollow of the sphere of ice2 #b;dly1 ,that the heat of the body placed in the hollow of the sphere cannot penetrate outwards beyond it1 but will be stopped at the internal surface1 and continually employed to melt successive layers of ice1 until the temperature of the body be reduced to ,zero 7#cb71 by having all its superabundant caloric above that temperature carried off by the ice4 ,if the whole water1 formed within the sphere of ice during the reduction of the temperature of the included body to ,zero1 be carefully collected1 the weight of the water will be exactly proportional to the quantity of caloric lost by the body in passing from its original temperature to that of melting ice2 for it is evident that a double quantity of caloric would have melted twice the quantity of ice2 hence the quantity of ice melted is a very exact measure of the quantity of caloric employed to produce that effect1 and consequently of the quantity lost by the only substance that could possibly have supplied it4 ,i have made this supposition of what would take place in a hollow sphere of ice1 for the purpose of more readily explaining the method used in this species of experiment1 which was first conceived by ,mr de la ,place4 ,it would be difficult to procure such spheres of ices and inconvenient to make use of them when got2 but1 by means of the following apparatus1 we have remedied that defect4 ,i acknowledge the name of ,calorimeter1 which ,i have given it1 as derived partly from ,greek and partly from ,latin1 is in some degree open to criticism2 but1 in matters of science1 a slight deviation from strict etymology1 for the sake of giving distinctness of idea1 is excusable2 and ,i could not derive the name entirely from ,greek without approaching too near to the names of known instruments employed for other purposes4 ,the calorimeter is represented in ,pl4 ,,vi4 ,it is shown in perspective at ,fig4 #a4 and its interior structure is engraved in ,fig4 #b4 and #c42 the former being a horizontal1 and the latter a perpendicular section4 ,its capacity or cavity is divided into three parts1 which1 for better distinction1 ,i shall name the interior1 middle1 and external cavities4 ,the interior cavity f f f f1 ,fig4 #d4 into which the substances submitted to experiment are put1 is composed of a grating or cage of iron wire1 supported by several iron bars2 its opening or mouth ,,lm1 is covered by the lid ,,hg1 of the same materials4 ,the middle cavity b b b b1 ,fig4 #b4 and #c4 is intended to contain the ice which surrounds the interior cavity1 and which is to be melted by the caloric of the substance employed in the experiment4 ,the ice is supported by the grate m m at the bottom of the cavity1 under which is placed the sieve n n4 ,these two are represented separately in ,fig4 #e4 and #f4 ,in proportion as the ice contained in the middle cavity is melted1 by the caloric disengaged from the body placed in the interior cavity1 the water runs through the grate and sieve1 and falls through the conical funnel c c d1 ,fig4 #c4 and tube x y1 into the receiver ,f1 ,fig4 #a4 ,this water may be retained or let out at pleasure1 by means of the stop-cock u4 ,the external cavity a a a a1 ,fig4 #b4 and #c4 is filled with ice1 to prevent any effect upon the ice in the middle cavity from the heat of the surrounding air1 and the water produced from it is carried off through the pipe ,,st1 which shuts by means of the stop-cock r4 ,the whole machine is covered by the lid ,,ff1 ,fig4 #g4 made of tin painted with oil colour1 to prevent rust4 ,when this machine is to be employed1 the middle cavity b b b b1 ,fig4 #b4 and #c41 the lid ,,gh1 ,fig4 #d4 of the interior cavity1 the external cavity a a a a1 ,fig4 #b4 and #c4 and the general lid ,,ff1 ,fig4 #g4 are all filled with pounded ice1 well rammed1 so that no void spaces remain1 and the ice of the middle cavity is allowed to drain4 ,the machine is then opened1 and the substance submitted to experiment being placed in the interior cavity1 it is instantly closed4 ,after waiting till the included body is completely cooled to the freezing point1 and the whole melted ice has drained from the middle cavity1 the water collected in the vessel ,f1 ,fig4 #a4 is accurately weighed4 ,the weight of the water produced during the experiment is an exact measure of the caloric disengaged during the cooling of the included body1 as this substance is evidently in a similar situation with the one formerly mentioned as included in a hollow sphere of ice2 the whole caloric disengaged is stopped by the ice in the middle cavity1 and that ice is preserved from being affected by any other heat by means of the ice contained in the general lid1 ,fig4 #g4 and in the external cavity4 ,experiments of this kind last from fifteen to twenty hours2 they are sometimes accelerated by covering up the substance in the interior cavity with well drained ice1 which hastens its cooling4 ,the substances to be operated upon are placed in the thin iron bucket1 ,fig4 #h4 the cover of which has an opening fitted with a cork1 into which a small thermometer is fixed4 ,when we use acids1 or other fluids capable of injuring the metal of the instruments1 they are contained in the matras1 ,fig4 #aj4 which has a similar thermometer in a cork fitted to its mouth1 and which stands in the interior cavity upon the small cylindrical support ,,rs1 ,fig4 #aj4 ,it is absolutely requisite that there be no communication between the external and middle cavities of the calorimeter1 otherwise the ice melted by the influence of the surrounding air1 in the external cavity1 would mix with the water produced from the ice of the middle cavity1 which would no longer be a measure of the caloric lost by the substance submitted to experiment4 ,when the temperature of the atmosphere is only a few degrees above the freezing point1 its heat can hardly reach the middle cavity1 being arrested by the ice of the cover1 ,fig4 #g4 and of the external cavity2 but1 if the temperature of the air be under the degree of freezing1 it might cool the ice contained in the middle cavity1 by causing the ice in the external cavity to fall1 in the first place1 below zero 7#cb74 ,it is therefore essential that this experiment be carried on in a temperature somewhat above freezing3 ,hence1 in time of frost1 the calorimeter must be kept in an apartment carefully heated4 ,it is likewise necessary that the ice employed be not under zero 7#cb72 for which purpose it must be pounded1 and spread out thin for some time1 in a place of a higher temperature4 ,the ice of the interior cavity always retains a certain quantity of water adhering to its surface1 which may be supposed to belong to the result of the experiment2 but as1 at the beginning of each experiment1 the ice is already saturated with as much water as it can contain1 if any of the water produced by the caloric should remain attached to the ice1 it is evident1 that very nearly an equal quantity of what adhered to it before the experiment must have run down into the vessel ,f in its stead2 for the inner surface of the ice in the middle cavity is very little changed during the experiment4 ,by any contrivance that could be devised1 we could not prevent the access of the external air into the interior cavity when the atmosphere was #i or #aj 7#eb or #ed7 above zero4 ,the air confined in the cavity being in that case specifically heavier than the external air1 escapes downwards through the pipe x y1 ,fig4 #c1 and is replaced by the warmer external air1 which1 giving out its caloric to the ice1 becomes heavier1 and sinks in its turn2 thus a current of air is formed through the machine1 which is the more rapid in proportion as the external air exceeds the internal in temperature4 ,this current of warm air must melt a part of the ice1 and injure the accuracy of the experiment3 ,we may1 in a great degree1 guard against this source of error by keeping the stop-cock u continually shut2 but it is better to operate only when the temperature of the external air does not exceed #c1 or at most #d1 7#ci to #da72 for we have observed1 that1 in this case1 the melting of the interior ice by the atmospheric air is perfectly insensible2 so that we may answer for the accuracy of our experiments upon the specific heat of bodies to a fortieth part4 ,we have caused make two of the above described machines2 one1 which is intended for such experiments as do not require the interior air to be renewed1 is precisely formed according to the description here given2 the other1 which answers for experiments upon combustion1 respiration1 c4 in which fresh quantities of air are indispensibly necessary1 differs from the former in having two small tubes in the two lids1 by which a current of atmospheric air may be blown into the interior cavity of the machine4 ,it is extremely easy1 with this apparatus1 to determine the phenomena which occur in operations where caloric is either disengaged or absorbed4 ,if we wish1 for instance1 to ascertain the quantity of caloric which is disengaged from a solid body in cooling a certain number of degrees1 let its temperature be raised to #hj 7#bab72 it is then placed in the interior cavity f f f f1 ,fig4 #b4 and #c4 of the calorimeter1 and allowed to remain till we are certain that its temperature is reduced to zero 7#cb72 the water produced by melting the ice during its cooling is collected1 and carefully weighed2 and this weight1 divided by the volume of the body submitted to experiment1 multiplied into the degrees of temperature which it had above zero at the commencement of the experiment1 gives the proportion of what the ,english philosophers call specific heat4 ,fluids are contained in proper vessels1 whose specific heat has been previously ascertained1 and operated upon in the machine in the same manner as directed for solids1 taking care to deduct1 from the quantity of water melted during the experiment1 the proportion which belongs to the containing vessel4 ,if the quantity of caloric disengaged during the combination of different substances is to be determined1 these substances are to be previously reduced to the freezing degree by keeping them a sufficient time surrounded with pounded ice2 the mixture is then to be made in the inner cavity of the calorimeter1 in a proper vessel likewise reduced to zero 7#cb72 and they are kept inclosed till the temperature of the combination has returned to the same degree3 ,the quantity of water produced is a measure of the caloric disengaged during the combination4 ,to determine the quantity of caloric disengaged during combustion1 and during animal respiration1 the combustible bodies are burnt1 or the animals are made to breathe in the interior cavity1 and the water produced is carefully collected4 ,guinea pigs1 which resist the effects of cold extremely well1 are well adapted for this experiment4 ,as the continual renewal of air is absolutely necessary in such experiments1 we blow fresh air into the interior cavity of the calorimeter by means of a pipe destined for that purpose1 and allow it to escape through another pipe of the same kind2 and that the heat of this air may not produce errors in the results of the experiments1 the tube which conveys it into the machine is made to pass through pounded ice1 that it may be reduced to zero 7#cb7 before it arrives at the calorimeter4 ,the air which escapes must likewise be made to pass through a tube surrounded with ice1 included in the interior cavity of the machine1 and the water which is produced must make a part of what is collected1 because the caloric disengaged from this air is part of the product of the experiment4 ,it is somewhat more difficult to determine the specific caloric contained in the different gasses1 on account of their small degree of density2 for1 if they are only placed in the calorimeter in vessels like other fluids1 the quantity of ice melted is so small1 that the result of the experiment becomes at best very uncertain4 ,for this species of experiment we have contrived to make the air pass through two metallic worms1 or spiral tubes2 one of these1 through which the air passes1 and becomes heated in its way to the calorimeter1 is contained in a vessel full of boiling water1 and the other1 through which the air circulates within the calorimeter to disengage its caloric1 is placed in the interior cavity1 f f f f1 of that machine4 ,by means of a small thermometer placed at one end of the second worm1 the temperature of the air1 as it enters the calorimeter1 is determined1 and its temperature in getting out of the interior cavity is found by another thermometer placed at the other end of the worm4 ,by this contrivance we are enabled to ascertain the quantity of ice melted by determinate quantities of air or gas1 while losing a certain number of degrees of temperature1 and1 consequently1 to determine their several degrees of specific caloric4 ,the same apparatus1 with some particular precautions1 may be employed to ascertain the quantity of caloric disengaged by the condensation of the vapours of different liquids4 ,the various experiments which may be made with the calorimeter do not afford absolute conclusions1 but only give us the measure of relative quantities2 we have therefore to fix a unit1 or standard point1 from whence to form a scale of the several results4 ,the quantity of caloric necessary to melt a pound of ice has been chosen as this unit2 and1 as it requires a pound of water of the temperature of #fj 7#afg7 to melt a pound of ice1 the quantity of caloric expressed by our unit or standard point is what raises a pound of water from zero 7#cb7 to #fj 7#afg74 ,when this unit is once determined1 we have only to express the quantities of caloric disengaged from different bodies by cooling a certain number of degrees1 in analogous values3 ,the following is an easy mode of calculation for this purpose1 applied to one of our earliest experiments4 ,we took #g lib4 #aa oz4 #b gros #cf grs4 of plate-iron1 cut into narrow slips1 and rolled up1 or expressing the quantity in decimals1 #g4gjgjcai4 ,these1 being heated in a bath of boiling water to about #gh 7#bjg4e71 were quickly introduced into the interior cavity of the calorimeter3 ,at the end of eleven hours1 when the whole quantity of water melted from the ice had thoroughly drained off1 we found that #a4ajigie pounds of ice were melted4 ,hence1 the caloric disengaged from the iron by cooling #gh 7#age4e7 having melted #a4ajigie pounds of ice1 how much would have been melted by cooling #fj 7#ace78 ,this question gives the following statement in direct proportion1 #gh 3 #a4ajigie 33 #fj 3 x #j4hecfi4 ,dividing this quantity by the weight of the whole iron employed1 viz4 #g4gjgjcai1 the quotient #j4aajggj is the quantity of ice which would have been melted by one pound of iron whilst cooling through #fj 7#ace7 of temperature4 ,fluid substances1 such as sulphuric and nitric acids1 c4 are contained in a matras1 ,pl4 ,,vi4 ,fig4 #i4 having a thermometer adapted to the cork1 with its bulb immersed in the liquid4 ,the matras is placed in a bath of boiling water1 and when1 from the thermometer1 we judge the liquid is raised to a proper temperature1 the matras is placed in the calorimeter4 ,the calculation of the products1 to determine the specific caloric of these fluids1 is made as above directed1 taking care to deduct from the water obtained the quantity which would have been produced by the matras alone1 which must be ascertained by a previous experiment4 ,the table of the results obtained by these experiments is omitted1 because not yet sufficiently complete1 different circumstances having occasioned the series to be interrupted2 it is not1 however1 lost sight of2 and we are less or more employed upon the subject every winter4 ,,chap4 ,,iv4 ,of ,mechanical ,operations for ,division of ,bodies4 ,,sect4 ,i4 ,of ,trituration1 ,levigation1 and ,pulverization4 ,these are1 properly speaking1 only preliminary mechanical operations for dividing and separating the particles of bodies1 and reducing them into very fine powder4 ,these operations can never reduce substances into their primary1 or elementary and ultimate particles2 they do not even destroy the aggregation of bodies2 for every particle1 after the most accurate trituration1 forms a small whole1 resembling the original mass from which it was divided4 ,the real chemical operations1 on the contrary1 such as solution1 destroy the aggregation of bodies1 and separate their constituent and integrant particles from each other4 ,brittle substances are reduced to powder by means of pestles and mortars4 ,these are of brass or iron1 ,pl4 ,i4 ,fig4 #a42 of marble or granite1 ,fig4 #b42 of lignum vitae1 ,fig4 #c42 of glass1 ,fig4 #d42 of agate1 ,fig4 #e42 or of porcellain1 ,fig4 #f4 ,the pestles for each of these are represented in the plate1 immediately below the mortars to which they respectively belong1 and are made of hammered iron or brass1 of wood1 glass1 porcellain1 marble1 granite1 or agate1 according to the nature of the substances they are intended to triturate4 ,in every laboratory1 it is requisite to have an assortment of these utensils1 of various sizes and kinds3 ,those of porcellain and glass can only be used for rubbing substances to powder1 by a dexterous use of the pestle round the sides of the mortar1 as it would be easily broken by reiterated blows of the pestle4 ,the bottom of mortars ought to be in the form of a hollow sphere1 and their sides should have such a degree of inclination as to make the substances they contain fall back to the bottom when the pestle is lifted1 but not so perpendicular as to collect them too much together1 otherwise too large a quantity would get below the pestle1 and prevent its operation4 ,for this reason1 likewise1 too large a quantity of the substance to be powdered ought not to be put into the mortar at one time2 and we must from time to time get rid of the particles already reduced to powder1 by means of sieves to be afterwards described4 ,the most usual method of levigation is by means of a flat table ,,abcd1 ,pl4 #a4 ,fig4 #g4 of porphyry1 or other stone of similar hardness1 upon which the substance to be reduced to powder is spread1 and is then bruised and rubbed by a muller ,m1 of the same hard materials1 the bottom of which is made a small portion of a large sphere2 and1 as the muller tends continually to drive the substances towards the sides of the table1 a thin flexible knife1 or spatula of iron1 horn1 wood1 or ivory1 is used for bringing them back to the middle of the stone4 ,in large works1 this operation is performed by means of large rollers of hard stone1 which turn upon each other1 either horizontally1 in the way of corn-mills1 or by one vertical roller turning upon a flat stone4 ,in the above operations1 it is often requisite to moisten the substances a little1 to prevent the fine powder from flying off4 ,there are many bodies which cannot be reduced to powder by any of the foregoing methods2 such are fibrous substances1 as woods2 such as are tough and elastic1 as the horns of animals1 elastic gum1 c4 and the malleable metals which flatten under the pestle1 instead of being reduced to powder4 ,for reducing the woods to powder1 rasps1 as ,pl4 ,i4 ,fig4 #h4 are employed2 files of a finer kind are used for horn1 and still finer1 ,pl4 #a4 ,fig4 #i4 and #aj4 for metals4 ,some of the metals1 though not brittle enough to powder under the pestle1 are too soft to be filed1 as they clog the file1 and prevent its operation4 ,zinc is one of these1 but it may be powdered when hot in a heated iron mortar1 or it may be rendered brittle1 by alloying it with a small quantity of mercury4 ,one or other of these methods is used by fire-work makers for producing a blue flame by means of zinc4 ,metals may be reduced into grains1 by pouring them when melted into water1 which serves very well when they are not wanted in fine powder4 ,fruits1 potatoes1 c4 of a pulpy and fibrous nature may be reduced to pulp by means of the grater1 ,pl4 #a4 ,fig4 #aa4 ,the choice of the different substances of which these instruments are made is a matter of importance2 brass or copper are unfit for operations upon substances to be used as food or in pharmacy2 and marble or metallic instruments must not be used for acid substances2 hence mortars of very hard wood1 and those of porcelain1 granite1 or glass1 are of great utility in many operations4 ,,sect4 ,,ii4 ,of ,sifting and ,washing ,powdered ,substances4 ,none of the mechanical operations employed for reducing bodies to powder is capable of producing it of an equal degree of fineness throughout2 the powder obtained by the longest and most accurate trituration being still an assemblage of particles of various sizes4 ,the coarser of these are removed1 so as only to leave the finer and more homogeneous particles by means of sieves1 ,pl4 ,i4 ,fig4 #ab4 #ac4 #ad4 #ae4 of different finenesses1 adapted to the particular purposes they are intended for2 all the powdered matter which is larger than the intestices of the sieve remains behind1 and is again submitted to the pestle1 while the finer pass through4 ,the sieve ,fig4 #ab4 is made of hair-cloth1 or of silk gauze2 and the one represented ,fig4 #ac4 is of parchment pierced with round holes of a proper size2 this latter is employed in the manufacture of gun-powder4 ,when very subtile or valuable materials are to be sifted1 which are easily dispersed1 or when the finer parts of the powder may be hurtful1 a compound sieve1 ,fig4 #ae4 is made use of1 which consists of the sieve ,,abcd1 with a lid ,,ef1 and receiver ,,gh2 these three parts are represented as joined together for use1 ,fig4 #ad4 ,there is a method of procuring powders of an uniform fineness1 considerably more accurate than the sieve2 but it can only be used with such substances as are not acted upon by water4 ,the powdered substance is mixed and agitated with water1 or other convenient fluid2 the liquor is allowed to settle for a few moments1 and is then decanted off2 the coarsest powder remains at the bottom of the vessel1 and the finer passes over with the liquid4 ,by repeated decantations in this manner1 various sediments are obtained of different degrees of fineness2 the last sediment1 or that which remains longed suspended in the liquor1 being the finest4 ,this process may likewise be used with advantage for separating substances of different degrees of specific gravity1 though of the same fineness2 this last is chiefly employed in mining1 for separating the heavier metallic ores from the lighter earthy matters with which they are mixed4 ,in chemical laboratories1 pans and jugs of glass or earthen ware are employed for this operation2 sometimes1 for decanting the liquor without disturbing the sediment1 the glass syphon ,,abchi1 ,pl4 ,,ii4 ,fig4 #aa4 is used1 which may be supported by means of the perforated board ,,de1 at the proper depth in the vessel ,,fg1 to draw off all the liquor required into the receiver ,,lm4 ,the principles and application of this useful instrument are so well known as to need no explanation4 ,,sect4 ,,iii4 ,of ,filtration4 ,a filtre is a species of very fine sieve1 which is permeable to the particles of fluids1 but through which the particles of the finest powdered solids are incapable of passing2 hence its use in separating fine powders from suspension in fluids4 ,in pharmacy1 very close and fine woollen cloths are chiefly used for this operation2 these are commonly formed in a conical shape1 ,pl4 ,,ii4 ,fig4 #b4 which has the advantage of uniting all the liquor which drains through into a point ,a1 where it may be readily collected in a narrow mouthed vessel4 ,in large pharmaceutical laboratories1 this filtring bag is streached upon a wooden stand1 ,pl4 ,,ii4 ,fig4 #a4 ,for the purposes of chemistry1 as it is requisite to have the filtres perfectly clean1 unsized paper is substituted instead of cloth or flannel2 through this substance1 no solid body1 however finely it be powdered1 can penetrate1 and fluids percolate through it with the greatest readiness4 ,as paper breaks easily when wet1 various methods of supporting it are used according to circumstances4 ,when a large quantity of fluid is to be filtrated1 the paper is supported by the frame of wood1 ,pl4 ,,ii4 ,fig4 #c4 ,,abcd1 having a piece of coarse cloth stretched over it1 by means of iron-hooks4 ,this cloth must be well cleaned each time it is used1 or even new cloth must be employed1 if there is reason to suspect its being impregnated with any thing which can injure the subsequent operations4 ,in ordinary operations1 where moderate quantities of fluid are to be filtrated1 different kinds of glass funnels are used for supporting the paper1 as represented ,pl4 ,,ii4 ,fig4 #e4 #f4 and #g4 ,when several filtrations must be carried on at once1 the board or shelf ,,ab1 ,fig4 #i4 supported upon stands ,c and ,d1 and pierced with round holes1 is very convenient for containing the funnels4 ,some liquors are so thick and clammy1 as not to be able to penetrate through paper without some previous preparation1 such as clarification by means of white of eggs1 which being mixed with the liquor1 coagulates when brought to boil1 and1 entangling the greater part of the impurities of the liquor1 rises with them to the surface in the state of scum4 ,spiritous liquors may be clarified in the same manner by means of isinglass dissolved in water1 which coagulates by the action of the alkohol without the assistance of heat4 ,as most of the acids are produced by distillation1 and are consequently clear1 we have rarely any occasion to filtrate them2 but if1 at any time1 concentrated acids require this operation1 it is impossible to employ paper1 which would be corroded and destroyed by the acid4 ,for this purpose1 pounded glass1 or rather quartz or rock-cristal1 broke in pieces and grossly powdered1 answers very well2 a few of the larger pieces are put in the neck of the funnel2 these are covered with the smaller pieces1 the finer powder is placed over all1 and the acid is poured on at top4 ,for the ordinary purposes of society1 river-water is frequently filtrated by means of clean washed sand1 to separate its impurities4 ,,sect4 ,,iv4 ,of ,decantation4 ,this operation is often substituted instead of filtration for separating solid particles which are diffused through liquors4 ,these are allowed to settle in conical vessels1 ,,abcde1 ,pl4 ,,ii4 ,fig4 #aj4 the diffused matters gradually subside1 and the clear fluid is gently poured off4 ,if the sediment be extremely light1 and apt to mix again with the fluid by the slightest motion1 the syphon1 ,fig4 #aa4 is used1 instead of decantation1 for drawing off the clear fluid4 ,in experiments1 where the weight of the precipitate must be rigorously ascertained1 decantation is preferable to filtration1 providing the precipitate be several times washed in a considerable proportion of water4 ,the weight of the precipitate may indeed be ascertained1 by carefully weighing the filtre before and after the operation2 but1 when the quantity of precipitate is small1 the different proportions of moisture retained by the paper1 in a greater or lesser degree of exsiccation1 may prove a material source of error1 which ought carefully to be guarded against4 ,,chap4 ,v4 ,of ,chemical ,means for separating the ,particles of ,bodies from each other2 without ,decomposition1 and for uniting them again4 ,i have already shown that there are two methods of dividing the particles of bodies1 the mechanical and chemical4 ,the former only separates a solid mass into a great number of smaller masses2 and for these purposes various species of forces are employed1 according to circumstances1 such as the strength of man or of animals1 the weight of water applied through the means of hydraulic engines1 the expansive power of steam1 the force of the wind1 c4 ,by all these mechanical powers1 we can never reduce substances into powder beyond a certain degree of fineness2 and the smallest particle produced in this way1 though it seems very minute to our organs1 is still in fact a mountain1 when compared with the ultimate elementary particles of the pulverized substance4 ,the chemical agents1 on the contrary1 divide bodies into their primitive particles4 ,if1 for instance1 a neutral salt be acted upon by these1 it is divided1 as far as is possible1 without ceasing to be a neutral salt4 ,in this ,chapter1 ,i mean to give examples of this kind of division of bodies1 to which ,i shall add some account of the relative operations4 ,,sect4 ,i4 ,of the ,solution of ,salts4 ,in chemical language1 the terms of solution and dissolution have long been confounded1 and have very improperly been indiscriminately employed for expressing both the division of the particles of a salt in a fluid1 such as water1 and the division of a metal in an acid4 ,a few reflections upon the effects of these two operations will suffice to show that they ought not to be confounded together4 ,in the solution of salts1 the saline particles are only separated from each other1 whilst neither the salt nor the water are at all decomposed2 we are able to recover both the one and the other in the same quantity as before the operation4 ,the same thing takes place in the solution of resins in alkohol4 ,during metallic dissolutions1 on the contrary1 a decomposition1 either of the acid1 or of the water which dilutes it1 always takes place2 the metal combines with oxygen1 and is changed into an oxyd1 and a gasseous substance is disengaged2 so that in reality none of the substances employed remain1 after the operation1 in the same state they were in before4 ,this article is entirely confined to the consideration of solution4 ,to understand properly what takes place during the solution of salts1 it is necessary to know1 that1 in most of these operations1 two distinct effects are complicated together1 viz4 solution by water1 and solution by caloric2 and1 as the explanation of most of the phenomena of solution depends upon the distinction of these two circumstances1 ,i shall enlarge a little upon their nature4 ,nitrat of potash1 usually called nitre or saltpetre1 contains very little water of cristallization1 perhaps even none at all2 yet this salt liquifies in a degree of heat very little superior to that of boiling water4 ,this liquifaction cannot therefore be produced by means of the water of cristallization1 but in consequence of the salt being very fusible in its nature1 and from its passing from the solid to the liquid state of aggregation1 when but a little raised above the temperature of boiling water4 ,all salts are in this manner susceptible of being liquified by caloric1 but in higher or lower degrees of temperature4 ,some of these1 as the acetites of potash and soda1 liquify with a very moderate heat1 whilst others1 as sulphat of potash1 lime1 c4 require the strongest fires we are capable of producing4 ,this liquifaction of salts by caloric produces exactly the same phenomena with the melting of ice2 it is accomplished in each salt by a determinate degree of heat1 which remains invariably the same during the whole time of the liquifaction4 ,caloric is employed1 and becomes fixed during the melting of the salt1 and is1 on the contrary1 disengaged when the salt coagulates4 ,these are general phenomena which universally occur during the passage of every species of substance from the solid to the fluid state of aggregation1 and from fluid to solid4 ,these phenomena arising from solution by caloric are always less or more conjoined with those which take place during solutions in water4 ,we cannot pour water upon a salt1 on purpose to dissolve it1 without employing a compound solvent1 both water and caloric2 hence we may distinguish several different cases of solution1 according to the nature and mode of existence of each salt4 ,if1 for instance1 a salt be difficultly soluble in water1 and readily so by caloric1 it evidently follows1 that this salt will be difficultly soluble in cold water1 and considerably in hot water2 such is nitrat of potash1 and more especially oxygenated muriat of potash4 ,if another salt be little soluble both in water and caloric1 the difference of its solubility in cold and warm water will be very inconsiderable2 sulphat of lime is of this kind4 ,from these considerations1 it follows1 that there is a necessary relation between the following circumstances2 the solubility of a salt in cold water1 its solubility in boiling water1 and the degree of temperature at which the same salt liquifies by caloric1 unassisted by water2 and that the difference of solubility in hot and cold water is so much greater in proportion to its ready solution in caloric1 or in proportion to its susceptibility of liquifying in a low degree of temperature4 ,the above is a general view of solution2 but1 for want of particular facts1 and sufficiently exact experiments1 it is still nothing more than an approximation towards a particular theory4 ,the means of compleating this part of chemical science is extremely simple2 we have only to ascertain how much of each salt is dissolved by a certain quantity of water at different degrees of temperature2 and as1 by the experiments published by ,mr de la ,place and me1 the quantity of caloric contained in a pound of water at each degree of the thermometer is accurately known1 it will be very easy to determine1 by simple experiments1 the proportion of water and caloric required for solution by each salt1 what quantity of caloric is absorbed by each at the moment of liquifaction1 and how much is disengaged at the moment of cristallization4 ,hence the reason why salts are more rapidly soluble in hot than in cold water is perfectly evident4 ,in all solutions of salts caloric is employed2 when that is furnished intermediately from the surrounding bodies1 it can only arrive slowly to the salt2 whereas this is greatly accelerated when the requisite caloric exists ready combined with the water of solution4 ,in general1 the specific gravity of water is augmented by holding salts in solution2 but there are some exceptions to the rule4 ,some time hence1 the quantities of radical1 of oxygen1 and of base1 which constitute each neutral salt1 the quantity of water and caloric necessary for solution1 the increased specific gravity communicated to water1 and the figure of the elementary particles of the cristals1 will all be accurately known4 ,from these all the circumstances and phenomena of cristallization will be explained1 and by these means this part of chemistry will be compleated4 ,mr ,seguin has formed the plan of a thorough investigation of this kind1 which he is extremely capable of executing4 ,the solution of salts in water requires no particular apparatus2 small glass phials of different sizes1 ,pl4 ,,ii4 ,fig4 #af4 and #ag4 pans of earthern ware1 ,a1 ,fig4 #a4 and #b4 long-necked matrasses1 ,fig4 #ad4 and pans or basons of copper or of silver1 ,fig4 #ac4 and #ae4 answer very well for these operations4 ,,sect4 ,,ii4 ,of ,lixiviation4 ,this is an operation used in chemistry and manufactures for separating substances which are soluble in water from such as are insoluble4 ,the large vat or tub1 ,pl4 ,,ii4 ,fig4 #ab4 having a hole ,d near its bottom1 containing a wooden spiget and fosset or metallic stop-cock ,,de1 is generally used for this purpose4 ,a thin stratum of straw is placed at the bottom of the tub2 over this1 the substance to be lixiviated is laid and covered by a cloth1 then hot or cold water1 according to the degree of solubility of the saline matter1 is poured on4 ,when the water is supposed to have dissolved all the saline parts1 it is let off by the stop-cock2 and1 as some of the water charged with salt necessarily adheres to the straw and insoluble matters1 several fresh quantities of water are poured on4 ,the straw serves to secure a proper passage for the water1 and may be compared to the straws or glass rods used in filtrating1 to keep the paper from touching the sides of the funnel4 ,the cloth which is laid over the matters under lixiviation prevents the water from making a hollow in these substances where it is poured on1 through which it might escape without acting upon the whole mass4 ,this operation is less or more imitated in chemical experiments2 but as in these1 especially with analytical views1 greater exactness is required1 particular precautions must be employed1 so as not to leave any saline or soluble part in the residuum4 ,more water must be employed than in ordinary lixiviations1 and the substances ought to be previously stirred up in the water before the clear liquor is drawn off1 otherwise the whole mass might not be equally lixiviated1 and some parts might even escape altogether from the action of the water4 ,we must likewise employ fresh portions of water in considerable quantity1 until it comes off entirely free from salt1 which we may ascertain by means of the hydrometer formerly described4 ,in experiments with small quantities1 this operation is conveniently performed in jugs or matrasses of glass1 and by filtrating the liquor through paper in a glass funnel4 ,when the substance is in larger quantity1 it may be lixiviated in a kettle of boiling water1 and filtrated through paper supported by cloth in the wooden frame1 ,pl4 ,,ii4 ,fig4 #c4 and #d42 and in operations in the large way1 the tub already mentioned must be used4 ,,sect4 ,,iii4 ,of ,evaporation4 ,this operation is used for separating two substances from each other1 of which one at least must be fluid1 and whose degrees of volatility are considerably different4 ,by this means we obtain a salt1 which has been dissolved in water1 in its concrete form2 the water1 by heating1 becomes combined with caloric1 which renders it volatile1 while the particles of the salt being brought nearer to each other1 and within the sphere of their mutual attraction1 unite into the solid state4 ,as it was long thought that the air had great influence upon the quantity of fluid evaporated1 it will be proper to point out the errors which this opinion has produced4 ,there certainly is a constant slow evaporation from fluids exposed to the free air2 and1 though this species of evaporation may be considered in some degree as a solution in air1 yet caloric has considerable influence in producing it1 as is evident from the refrigeration which always accompanies this process2 hence we may consider this gradual evaporation as a compound solution made partly in air1 and partly in caloric4 ,but the evaporation which takes place from a fluid kept continually boiling1 is quite different in its nature1 and in it the evaporation produced by the action of the air is exceedingly inconsiderable in comparison with that which is occasioned by caloric4 ,this latter species may be termed vaporization rather than evaporation4 ,this process is not accelerated in proportion to the extent of evaporating surface1 but in proportion to the quantities of caloric which combine with the fluid4 ,too free a current of cold air is often hurtful to this process1 as it tends to carry off caloric from the water1 and consequently retards its conversion into vapour4 ,hence there is no inconvenience produced by covering1 in a certain degree1 the vessels in which liquids are evaporated by continual boiling1 provided the covering body be of such a nature as does not strongly draw off the caloric1 or1 to use an expression of ,dr ,franklin's1 provided it be a bad conductor of heat4 ,in this case1 the vapours escape through such opening as is left1 and at least as much is evaporated1 frequently more than when free access is allowed to the external air4 ,as during evaporation the fluid carried off by caloric is entirely lost1 being sacrificed for the sake of the fixed substances with which it was combined1 this process is only employed where the fluid is of small value1 as water1 for instance4 ,but1 when the fluid is of more consequence1 we have recourse to distillation1 in which process we preserve both the fixed substance and the volatile fluid4 ,the vessels employed for evaporation are basons or pans of copper1 silver1 or lead1 ,pl4 ,,ii4 ,fig4 #ac4 and #ae4 or capsules of glass1 porcellain1 or stone ware1 ,pl4 ,,ii4 ,a1 ,fig4 #a4 and #b4 ,pl4 ,,iii4 ,fig4 #c and #d4 ,the best utensils for this purpose are made of the bottoms of glass retorts and matrasses1 as their equal thinness renders them more fit than any other kind of glass vessel for bearing a brisk fire and sudden alterations of heat and cold without breaking4 ,as the method of cutting these glass vessels is no where described in books1 ,i shall here give a description of it1 that they may be made by chemists for themselves out of spoiled retorts1 matrasses1 and recipients1 at a much cheaper rate than any which can be procured from glass manufacturers4 ,the instrument1 ,pl4 ,,iii4 ,fig4 #e4 consisting of an iron ring ,,ac1 fixed to the rod ,,ab1 having a wooden handle ,d1 is employed as follows3 ,make the ring red hot in the fire1 and put it upon the matrass ,g1 ,fig4 #f4 which is to be cut2 when the glass is sufficiently heated1 throw on a little cold water1 and it will generally break exactly at the circular line heated by the ring4 ,small flasks or phials of thin glass are exceeding good vessels for evaporating small quantities of fluid2 they are very cheap1 and stand the fire remarkably4 ,one or more of these may be placed upon a second grate above the furnace1 ,pl4 ,,iii4 ,fig4 #b4 where they will only experience a gentle heat4 ,by this means a great number of experiments may be carried on at one time4 ,a glass retort1 placed in a sand bath1 and covered with a dome of baked earth1 ,pl4 ,,iii4 ,fig4 #a4 answers pretty well for evaporations2 but in this way it is always considerably slower1 and is even liable to accidents2 as the sand heats unequally1 and the glass cannot dilate in the same unequal manner1 the retort is very liable to break4 ,sometimes the sand serves exactly the office of the iron ring formerly mentioned2 for1 if a single drop of vapour1 condensed into liquid1 happens to fall upon the heated part of the vessel1 it breaks circularly at that place4 ,when a very intense fire is necessary1 earthen crucibles may be used2 but we generally use the word evaporation to express what is produced by the temperature of boiling water1 or not much higher4 ,,sect4 ,,iv4 ,of ,cristallization4 ,in this process the integrant parts of a solid body1 separated from each other by the intervention of a fluid1 are made to exert the mutual attraction of aggregation1 so as to coalesce and reproduce a solid mass4 ,when the particles of a body are only separated by caloric1 and the substance is thereby retained in the liquid state1 all that is necessary for making it cristallize1 is to remove a part of the caloric which is lodged between its particles1 or1 in other words1 to cool it4 ,if this refrigeration be slow1 and the body be at the same time left at rest1 its particles assume a regular arrangement1 and cristallization1 properly so called1 takes place2 but1 if the refrigeration is made rapidly1 or if the liquor be agitated at the moment of its passage to the concrete state1 the cristallization is irregular and confused4 ,the same phenomena occur with watery solutions1 or rather in those made partly in water1 and partly by caloric4 ,so long as there remains a sufficiency of water and caloric to keep the particles of the body asunder beyond the sphere of their mutual attraction1 the salt remains in the fluid state2 but1 whenever either caloric or water is not present in sufficient quantity1 and the attraction of the particles for each other becomes superior to the power which keeps them asunder1 the salt recovers its concrete form1 and the cristals produced are the more regular in proportion as the evaporation has been slower and more tranquilly performed4 ,all the phenomena we formerly mentioned as taking place during the solution of salts1 occur in a contrary sense during their cristallization4 ,caloric is disengaged at the instant of their assuming the solid state1 which furnishes an additional proof of salt being held in solution by the compound action of water and caloric4 ,hence1 to cause salts to cristallize which readily liquify by means of caloric1 it is not sufficient to carry off the water which held them in solution1 but the caloric united to them must likewise be removed4 ,nitrat of potash1 oxygenated muriat of potash1 alum1 sulphat of soda1 c4 are examples of this circumstance1 as1 to make these salts cristallize1 refrigeration must be added to evaporation4 ,such salts1 on the contrary1 as require little caloric for being kept in solution1 and which1 from that circumstance1 are nearly equally soluble in cold and warm water1 are cristallizable by simply carrying off the water which holds them in solution1 and even recover their solid state in boiling water2 such are sulphat of lime1 muriat of potash and of soda1 and several others4 ,the art of refining saltpetre depends upon these properties of salts1 and upon their different degrees of solubility in hot and cold water4 ,this salt1 as produced in the manufactories by the first operation1 is composed of many different salts2 some are deliquescent1 and not susceptible of being cristallized1 such as the nitrat and muriat of lime2 others are almost equally soluble in hot and cold water1 as the muriats of potash and of soda2 and1 lastly1 the saltpetre1 or nitrat of potash1 is greatly more soluble in hot than it is in cold water4 ,the operation is begun1 by pouring upon this mixture of salts as much water as will hold even the least soluble1 the muriats of soda and of potash1 in solution2 so long as it is hot1 this quantity readily dissolves all the saltpetre1 but1 upon cooling1 the greater part of this salt cristallizes1 leaving about a sixth part remaining dissolved1 and mixed with the nitrat of lime and the two muriats4 ,the nitre obtained by this process is still somewhat impregnated with other salts1 because it has been cristallized from water in which these abound3 ,it is completely purified from these by a second solution in a small quantity of boiling water1 and second cristallization4 ,the water remaining after these cristallizations of nitre is still loaded with a mixture of saltpetre1 and other salts2 by farther evaporation1 crude saltpetre1 or rough-petre1 as the workmen call it1 is procured from it1 and this is purified by two fresh solutions and cristallizations4 ,the deliquescent earthy salts which do not contain the nitric acid are rejected in this manufacture2 but those which consist of that acid neutralized by an earthy base are dissolved in water1 the earth is precipitated by means of potash1 and allowed to subside2 the clear liquor is then decanted1 evaporated1 and allowed to cristallize4 ,the above management for refining saltpetre may serve as a general rule for separating salts from each other which happen to be mixed together4 ,the nature of each must be considered1 the proportion in which each dissolves in given quantities of water1 and the different solubility of each in hot and cold water4 ,if to these we add the property which some salts possess1 of being soluble in alkohol1 or in a mixture of alkohol and water1 we have many resources for separating salts from each other by means of cristallization1 though it must be allowed that it is extremely difficult to render this separation perfectly complete4 ,the vessels used for cristallization are pans of earthen ware1 ,a1 ,pl4 ,,ii4 ,fig4 #a4 and #b4 and large flat dishes1 ,pl4 ,,iii4 ,fig4 #g4 ,when a saline solution is to be exposed to a slow evaporation in the heat of the atmosphere1 with free access of air1 vessels of some depth1 ,pl4 ,,iii4 ,fig4 #c4 must be employed1 that there may be a considerable body of liquid2 by this means the cristals produced are of considerable size1 and remarkably regular in their figure4 ,every species of salt cristallizes in a peculiar form1 and even each salt varies in the form of its cristals according to circumstances1 which take place during cristallization4 ,we must not from thence conclude that the saline particles of each species are indeterminate in their figures3 ,the primative particles of all bodies1 especially of salts1 are perfectly constant in their specific forms2 but the cristals which form in our experiments are composed of congeries of minute particles1 which1 though perfectly equal in size and shape1 may assume very dissimilar arrangements1 and consequently produce a vast variety of regular forms1 which have not the smallest apparent resemblance to each other1 nor to the original cristal4 ,this subject has been very ably treated by the ,abb ,hay1 in several memoirs presented to the ,academy1 and in his work upon the structure of cristals3 ,it is only necessary to extend generally to the class of salts the principles he has particularly applied to some cristalized stones4 ,,sect4 ,v4 ,of ,simple ,distillation4 ,as distillation has two distinct objects to accomplish1 it is divisible into simple and compound2 and1 in this section1 ,i mean to confine myself entirely to the former4 ,when two bodies1 of which one is more volatile than the other1 or has more affinity to caloric1 are submitted to distillation1 our intention is to separate them from each other3 ,the more volatile substance assumes the form of gas1 and is afterwards condensed by refrigeration in proper vessels4 ,in this case distillation1 like evaporation1 becomes a species of mechanical operation1 which separates two substances from each other without decomposing or altering the nature of either4 ,in evaporation1 our only object is to preserve the fixed body1 without paying any regard to the volatile matter2 whereas1 in distillation1 our principal attention is generally paid to the volatile substance1 unless when we intend to preserve both the one and the other4 ,hence1 simple distillation is nothing more than evaporation produced in close vessels4 ,the most simple distilling vessel is a species of bottle or matrass1 ,a1 ,pl4 ,,iii4 ,fig4 #h4 which has been bent from its original form ,,bc to ,,bd1 and which is then called a retort2 when used1 it is placed either in a reverberatory furnace1 ,pl4 ,,xiii4 ,fig4 #b4 or in a sand bath under a dome of baked earth1 ,pl4 ,,iii4 ,fig4 #a4 ,to receive and condense the products1 we adapt a recipient1 ,e1 ,pl4 ,,iii4 ,fig4 #i4 which is luted to the retort4 ,sometimes1 more especially in pharmaceutical operations1 the glass or stone ware cucurbit1 ,a1 with its capital ,b1 ,pl4 ,,iii4 ,fig4 #ab1 or the glass alembic and capital1 ,fig4 #ac4 of one piece1 is employed4 ,this latter is managed by means of a tubulated opening ,t1 fitted with a ground stopper of cristal2 the capital1 both of the cucurbit and alembic1 has a furrow or trench1 r r1 intended for conveying the condensed liquor into the beak ,,rs1 by which it runs out4 ,as1 in almost all distillations1 expansive vapours are produced1 which might burst the vessels employed1 we are under the necessity of having a small hole1 ,t1 ,fig4 #i4 in the balloon or recipient1 through which these may find vent2 hence1 in this way of distilling1 all the products which are permanently ariform are entirely lost1 and even such as difficultly lose that state have not sufficient space to condense in the balloon3 ,this apparatus is not1 therefore1 proper for experiments of investigation1 and can only be admitted in the ordinary operations of the laboratory or in pharmacy4 ,in the article appropriated for compound distillation1 ,i shall explain the various methods which have been contrived for preserving the whole products from bodies in this process4 ,as glass or earthen vessels are very brittle1 and do not readily bear sudden alterations of heat and cold1 every well regulated laboratory ought to have one or more alembics of metal for distilling water1 spiritous liquors1 essential oils1 c4 ,this apparatus consists of a cucurbit and capital of tinned copper or brass1 ,pl4 ,,iii4 ,fig4 #ae4 and #af4 which1 when judged proper1 may be placed in the water bath1 ,d1 ,fig4 #ag4 ,in distillations1 especially of spiritous liquors1 the capital must be furnished with a refrigetory1 ,,ss1 ,fig4 #af4 kept continually filled with cold water2 when the water becomes heated1 it is let off by the stop-cock1 ,r1 and renewed with a fresh supply of cold water4 ,as the fluid distilled is converted into gas by means of caloric furnished by the fire of the furnace1 it is evident that it could not condense1 and1 consequently1 that no distillation1 properly speaking1 could take place1 unless it is made to deposit in the capital all the caloric it received in the cucurbit2 with this view1 the sides of the capital must always be preserved at a lower temperature than is necessary for keeping the distilling substance in the state of gas1 and the water in the refrigetory is intended for this purpose4 ,water is converted into gas by the temperature of #hj 7#bab71 alkohol by #fg 7#ahb4ge71 ether by #cb 7#ajd72 hence these substances cannot be distilled1 or1 rather1 they will fly off in the state of gas1 unless the temperature of the refrigetory be kept under these respective degrees4 ,in the distillation of spiritous1 and other expansive liquors1 the above described refrigetory is not sufficient for condensing all the vapours which arise2 in this case1 therefore1 instead of receiving the distilled liquor immediately from the beak1 ,,tu1 of the capital into a recipient1 a worm is interposed between them4 ,this instrument is represented ,pl4 ,,iii4 ,fig4 #ah4 contained in a worm tub of tinned copper1 it consists of a metallic tube bent into a considerable number of spiral revolutions4 ,the vessel which contains the worm is kept full of cold water1 which is renewed as it grows warm4 ,this contrivance is employed in all distilleries of spirits1 without the intervention of a capital and refrigetory1 properly so called4 ,the one represented in the plate is furnished with two worms1 one of them being particularly appropriated to distillations of odoriferous substances4 ,in some simple distillations it is necessary to interpose an adopter between the retort and receiver1 as shown ,pl4 ,,iii4 ,fig1 #aa4 ,this may serve two different purposes1 either to separate two products of different degrees of volatility1 or to remove the receiver to a greater distance from the furnace1 that it may be less heated4 ,but these1 and several other more complicated instruments of ancient contrivance1 are far from producing the accuracy requisite in modern chemistry1 as will be readily perceived when ,i come to treat of compound distillation4 ,,sect4 ,,vi4 ,of ,sublimation4 ,this term is applied to the distillation of substances which condense in a concrete or solid form1 such as the sublimation of sulphur1 and of muriat of ammoniac1 or sal ammoniac4 ,these operations may be conveniently performed in the ordinary distilling vessels already described1 though1 in the sublimation of sulphur1 a species of vessels1 named ,alludels1 have been usually employed4 ,these are vessels of stone or porcelain ware1 which adjust to each other over a cucurbit containing the sulphur to be sublimed4 ,one of the best subliming vessels1 for substances which are not very volatile1 is a flask1 or phial of glass1 sunk about two thirds into a sand bath2 but in this way we are apt to lose a part of the products4 ,when these are wished to be entirely preserved1 we must have recourse to the pneumato-chemical distilling apparatus1 to be described in the following chapter4 ,,chap4 ,,vi4 ,of ,pneumato-chemical ,distillations1 ,metallic ,dissolutions1 and some other operations which require very complicated instruments4 ,,sect4 ,i4 ,of ,compound and ,pneumato-chemical ,distillations4 ,in the preceding chapter1 ,i have only treated of distillation as a simple operation1 by which two substances1 differing in degrees of volatility1 may be separated from each other2 but distillation often actually decomposes the substances submitted to its action1 and becomes one of the most complicated operations in chemistry4 ,in every distillation1 the substance distilled must be brought to the state of gas1 in the cucurbit or retort1 by combination with caloric3 ,in simple distillation1 this caloric is given out in the refrigeratory or in the worm1 and the substance again recovers its liquid or solid form1 but the substances submitted to compound distillation are absolutely decompounded2 one part1 as for instance the charcoal they contain1 remains fixed in the retort1 and all the rest of the elements are reduced to gasses of different kinds4 ,some of these are susceptible of being condensed1 and of recovering their solid or liquid forms1 whilst others are permanently ariform2 one part of these are absorbable by water1 some by the alkalies1 and others are not susceptible of being absorbed at all4 ,an ordinary distilling apparatus1 such as has been described in the preceding chapter1 is quite insufficient for retaining or for separating these diversified products1 and we are obliged to have recourse1 for this purpose1 to methods of a more complicated nature4 ,the apparatus ,i am about to describe is calculated for the most complicated distillations1 and may be simplified according to circumstances4 ,it consists of a tubulated glass retort ,a1 ,pl4 ,,iv4 ,fig4 #a4 having its beak fitted to a tubulated balloon or recipient ,,bc2 to the upper orifice ,d of the balloon a bent tube ,d,efg is adjusted1 which1 at its other extremity g1 is plunged into the liquor contained in the bottle ,l1 with three necks xxx4 ,three other similar bottles are connected with this first one1 by means of three similar bent tubes disposed in the same manner2 and the farthest neck of the last bottle is connected with a jar in a pneumato-chemical apparatus1 by means of a bent tube#fj4 ,a determinate weight of distilled water is usually put into the first bottle1 and the other three have each a solution of caustic potash in water4 ,the weight of all these bottles1 and of the water and alkaline solution they contain1 must be accurately ascertained4 ,every thing being thus disposed1 the junctures between the retort and recipient1 and of the tube ,d of the latter1 must be luted with fat lute1 covered over with slips of linen1 spread with lime and white of egg2 all the other junctures are to be secured by a lute made of wax and rosin melted together4 ,when all these dispositions are completed1 and when1 by means of heat applied to the retort ,a1 the substance it contains becomes decomposed1 it is evident that the least volatile products must condense or sublime in the beak or neck of the retort itself1 where most of the concrete substances will fix themselves4 ,the more volatile substances1 as the lighter oils1 ammoniac1 and several others1 will condense in the recipient ,,gc1 whilst the gasses1 which are not susceptible of condensation by cold1 will pass on by the tubes1 and boil up through the liquors in the several bottles4 ,such as are absorbable by water will remain in the first bottle1 and those which caustic alkali can absorb will remain in the others2 whilst such gasses as are not susceptible of absorption1 either by water or alkalies1 will escape by the tube ,,rm1 at the end of which they may be received into jars in a pneumato-chemical apparatus4 ,the charcoal and fixed earth1 c4 which form the substance or residuum1 anciently called caput mortuum1 remain behind in the retort4 ,in this manner of operating1 we have always a very material proof of the accuracy of the analysis1 as the whole weights of the products taken together1 after the process is finished1 must be exactly equal to the weight of the original substance submitted to distillation4 ,hence1 for instance1 if we have operated upon eight ounces of starch or gum arabic1 the weight of the charry residuum in the retort1 together with that of all the products gathered in its neck and the balloon1 and of all the gas received into the jars by the tube ,,rm added to the additional weight acquired by the bottles1 must1 when taken together1 be exactly eight ounces4 ,if the product be less or more1 it proceeds from error1 and the experiment must be repeated until a satisfactory result be procured1 which ought not to differ more than six or eight grains in the pound from the weight of the substance submitted to experiment4 ,in experiments of this kind1 ,i for a long time met with an almost insurmountable difficulty1 which must at last have obliged me to desist altogether1 but for a very simple method of avoiding it1 pointed out to me by ,mr ,hassenfratz4 ,the smallest diminution in the heat of the furnace1 and many other circumstances inseparable from this kind of experiments1 cause frequent reabsorptions of gas2 the water in the cistern of the pneumato-chemical apparatus rushes into the last bottle through the tube ,,rm1 the same circumstance happens from one bottle into another1 and the fluid is often forced even into the recipient ,c4 ,this accident is prevented by using bottles having three necks1 as represented in the plate1 into one of which1 in each bottle1 a capillary glass-tube ,st1 st1 st1 st1 is adapted1 so as to have its lower extremity t immersed in the liquor4 ,if any absorption takes place1 either in the retort1 or in any of the bottles1 a sufficient quantity of external air enters1 by means of these tubes1 to fill up the void2 and we get rid of the inconvenience at the price of having a small mixture of common air with the products of the experiment1 which is thereby prevented from failing altogether4 ,though these tubes admit the external air1 they cannot permit any of the gasseous substances to escape1 as they are always shut below by the water of the bottles4 ,it is evident that1 in the course of experiments with this apparatus1 the liquor of the bottles must rise in these tubes in proportion to the pressure sustained by the gas or air contained in the bottles2 and this pressure is determined by the height and gravity of the column of fluid contained in all the subsequent bottles4 ,if we suppose that each bottle contains three inches of fluid1 and that there are three inches of water in the cistern of the connected apparatus above the orifice of the tube ,,rm1 and allowing the gravity of the fluids to be only equal to that of water1 it follows that the air in the first bottle must sustain a pressure equal to twelve inches of water2 the water must therefore rise twelve inches in the tube ,s1 connected with the first bottle1 nine inches in that belonging to the second1 six inches in the third1 and three in the last2 wherefore these tubes must be made somewhat more than twelve1 nine1 six1 and three inches long respectively1 allowance being made for oscillatory motions1 which often take place in the liquids4 ,it is sometimes necessary to introduce a similar tube between the retort and recipient2 and1 as the tube is not immersed in fluid at its lower extremity1 until some has collected in the progress of the distillation1 its upper end must be shut at first with a little lute1 so as to be opened according to necessity1 or after there is sufficient liquid in the recipient to secure its lower extremity4 ,this apparatus cannot be used in very accurate experiments1 when the substances intended to be operated upon have a very rapid action upon each other1 or when one of them can only be introduced in small successive portions1 as in such as produce violent effervescence when mixed together4 ,in such cases1 we employ a tubulated retort ,a1 ,pl4 ,,vii4 ,fig4 #a4 into which one of the substances is introduced1 preferring always the solid body1 if any such is to be treated1 we then lute to the opening of the retort a bent tube ,,bcda1 terminating at its upper extremity ,b in a funnel1 and at its other end ,a in a capillary opening4 ,the fluid material of the experiment is poured into the retort by means of this funnel1 which must be made of such a length1 from ,b to ,c1 that the column of liquid introduced may counterbalance the resistance produced by the liquors contained in all the bottles1 ,pl4 ,,iv4 ,fig4 #a4 ,those who have not been accustomed to use the above described distilling apparatus may perhaps be startled at the great number of openings which require luting1 and the time necessary for making all the previous preparations in experiments of this kind4 ,it is very true that1 if we take into account all the necessary weighings of materials and products1 both before and after the experiments1 these preparatory and succeeding steps require much more time and attention than the experiment itself4 ,but1 when the experiment succeeds properly1 we are well rewarded for all the time and trouble bestowed1 as by one process carried on in this accurate manner much more just and extensive knowledge is acquired of the nature of the vegetable or animal substance thus submitted to investigation1 than by many weeks assiduous labour in the ordinary method of proceeding4 ,when in want of bottles with three orifices1 those with two may be used2 it is even possible to introduce all the three tubes at one opening1 so as to employ ordinary wide-mouthed bottles1 provided the opening be sufficiently large4 ,in this case we must carefully fit the bottles with corks very accurately cut1 and boiled in a mixture of oil1 wax1 and turpentine4 ,these corks are pierced with the necessary holes for receiving the tubes by means of a round file1 as in ,pl4 ,,iv4 ,fig4 #h4 ,,sect4 ,,ii4 ,of ,metallic ,dissolutions4 ,i have already pointed out the difference between solution of salts in water and metallic dissolutions4 ,the former requires no particular vessels1 whereas the latter requires very complicated vessels of late invention1 that we may not lose any of the products of the experiment1 and may thereby procure truly conclusive results of the phenomena which occur4 ,the metals1 in general1 dissolve in acids with effervescence1 which is only a motion excited in the solvent by the disengagement of a great number of bubbles of air or ariform fluid1 which proceed from the surface of the metal1 and break at the surface of the liquid4 ,mr ,cavendish and ,dr ,priestley were the first inventors of a proper apparatus for collecting these elastic fluids4 ,that of ,dr ,priestley is extremely simple1 and consists of a bottle ,a1 ,pl4 ,,vii4 ,fig4 #b4 with its cork ,b1 through which passes the bent glass tube ,,bc1 which is engaged under a jar filled with water in the pneumato-chemical apparatus1 or simply in a bason full of water4 ,the metal is first introduced into the bottle1 the acid is then poured over it1 and the bottle is instantly closed with its cork and tube1 as represented in the plate4 ,but this apparatus has its inconveniencies4 ,when the acid is much concentrated1 or the metal much divided1 the effervescence begins before we have time to cork the bottle properly1 and some gas escapes1 by which we are prevented from ascertaining the quantity disengaged with rigorous exactness4 ,in the next place1 when we are obliged to employ heat1 or when heat is produced by the process1 a part of the acid distills1 and mixes with the water of the pneumato-chemical apparatus1 by which means we are deceived in our calculation of the quantity of acid decomposed4 ,besides these1 the water in the cistern of the apparatus absorbs all the gas produced which is susceptible of absorption1 and renders it impossible to collect these without loss4 ,to remedy these inconveniencies1 ,i at first used a bottle with two necks1 ,pl4 ,,vii4 ,fig4 #c4 into one of which the glass funnel ,,bc is luted so as to prevent any air escaping2 a glass rod ,,de is fitted with emery to the funnel1 so as to serve the purpose of a stopper4 ,when it is used1 the matter to be dissolved is first introduced into the bottle1 and the acid is then permitted to pass in as slowly as we please1 by raising the glass rod gently as often as is necessary until saturation is produced4 ,another method has been since employed1 which serves the same purpose1 and is preferable to the last described in some instances4 ,this consists in adapting to one of the mouths of the bottle ,a1 ,pl4 ,,vii4 ,fig4 #d4 a bent tube ,,defg1 having a capillary opening at ,d1 and ending in a funnel at ,g4 ,this tube is securely luted to the mouth ,c of the bottle4 ,when any liquid is poured into the funnel1 it falls down to ,f2 and1 if a sufficient quantity be added1 it passes by the curvature ,e1 and falls slowly into the bottle1 so long as fresh liquor is supplied at the funnel4 ,the liquor can never be forced out of the tube1 and no gas can escape through it1 because the weight of the liquid serves the purpose of an accurate cork4 ,to prevent any distillation of acid1 especially in dissolutions accompanied with heat1 this tube is adapted to the retort ,a1 ,pl4 ,,vii4 ,fig4 #a4 and a small tubulated recipient1 ,m1 is applied1 in which any liquor which may distill is condensed4 ,on purpose to separate any gas that is absorbable by water1 we add the double necked bottle ,l1 half filled with a solution of caustic potash2 the alkali absorbs any carbonic acid gas1 and usually only one or two other gasses pass into the jar of the connected pneumato-chemical apparatus through the tube ,,no4 ,in the first chapter of this third part we have directed how these are to be separated and examined4 ,if one bottle of alkaline solution be not thought sufficient1 two1 three1 or more1 may be added4 ,,sect4 ,,iii4 ,apparatus necessary in ,experiments upon ,vinous and ,putrefactive ,fermentations4 ,for these operations a peculiar apparatus1 especially intended for this kind of experiment1 is requisite4 ,the one ,i am about to describe is finally adopted1 as the best calculated for the purpose1 after numerous corrections and improvements4 ,it consists of a large matrass1 ,a1 ,pl4 ,x4 fig4 #a4 holding about twelve pints1 with a cap of brass a b1 strongly cemented to its mouth1 and into which is screwed a bent tube c d1 furnished with a stop-cock e4 ,to this tube is joined the glass recipient ,b1 having three openings1 one of which communicates with the bottle ,c1 placed below it4 ,to the posterior opening of this recipient is fitted a glass tube g h i1 cemented at g and i to collets of brass1 and intended to contain a very deliquescent concrete neutral salt1 such as nitrat or muriat of lime1 acetite of potash1 c4 ,this tube communicates with two bottles ,d and ,e1 filled to x and y with a solution of caustic potash4 ,all the parts of this machine are joined together by accurate screws1 and the touching parts have greased leather interposed1 to prevent any passage of air4 ,each piece is likewise furnished with two stop-cocks1 by which its two extremities may be closed1 so that we can weigh each separately at any period of the operation4 ,the fermentable matter1 such as sugar1 with a proper quantity of yeast1 and diluted with water1 is put into the matrass4 ,sometimes1 when the fermentation is too rapid1 a considerable quantity of froth is produced1 which not only fills the neck of the matrass1 but passes into the recipient1 and from thence runs down into the bottle ,c4 ,on purpose to collect this scum and must1 and to prevent it from reaching the tube filled with deliquescent salts1 the recipient and connected bottle are made of considerable capacity4 ,in the vinous fermentation1 only carbonic acid gas is disengaged1 carrying with it a small proportion of water in solution4 ,a great part of this water is deposited in passing through the tube g h i1 which is filled with a deliquescent salt in gross powder1 and the quantity is ascertained by the augmentation of the weight of the salt4 ,the carbonic acid gas bubbles up through the alkaline solution in the bottle ,d1 to which it is conveyed by the tube k l m4 ,any small portion which may not be absorbed by this first bottle is secured by the solution in the second bottle ,e1 so that nothing1 in general1 passes into the jar ,f1 except the common air contained in the vessels at the commencement of the experiment4 ,the same apparatus answers extremely well for experiments upon the putrefactive fermentation2 but1 in this case1 a considerable quantity of hydrogen gas is disengaged through the tube q r s t u1 by which it is conveyed into the jar ,f2 and1 as this disengagement is very rapid1 especially in summer1 the jar must be frequently changed4 ,these putrefactive fermentations require constant attendance from the above circumstance1 whereas the vinous fermentation hardly needs any4 ,by means of this apparatus we can ascertain1 with great precision1 the weights of the substances submitted to fermentation1 and of the liquid and ariform products which are disengaged4 ,what has been already said in ,part ,i4 ,chap4 ,,xiii4 upon the products of the vinous fermentation1 may be consulted4 ,,sect4 ,,iv4 ,apparatus for the ,decomposition of ,water4 ,having already given an account1 in the first part of this work1 of the experiments relative to the decomposition of water1 ,i shall avoid any unnecessary repetitions1 and only give a few summary observations upon the subject in this section4 ,the principal substances which have the power of decomposing water are iron and charcoal2 for which purpose1 they require to be made red hot1 otherwise the water is only reduced into vapours1 and condenses afterwards by refrigeration1 without sustaining the smallest alteration4 ,in a red heat1 on the contrary1 iron or charcoal carry off the oxygen from its union with hydrogen2 in the first case1 black oxyd of iron is produced1 and the hydrogen is disengaged pure in form of gas2 in the other case1 carbonic acid gas is formed1 which disengages1 mixed with the hydrogen gas2 and this latter is commonly carbonated1 or holds charcoal in solution4 ,a musket barrel1 without its breach pin1 answers exceedingly well for the decomposition of water1 by means of iron1 and one should be chosen of considerable length1 and pretty strong4 ,when too short1 so as to run the risk of heating the lute too much1 a tube of copper is to be strongly soldered to one end4 ,the barrel is placed in a long furnace1 ,,cdef1 ,pl4 ,,vii4 ,fig4 #aa4 so as to have a few degrees of inclination from ,e to ,f2 a glass retort ,a1 is luted to the upper extremity ,e1 which contains water1 and is placed upon the furnace ,,vvxx4 ,the lower extremity ,f is luted to a worm ,,ss1 which is connected with the tubulated bottle ,h1 in which any water distilled without decomposition1 during the operation1 collects1 and the disengaged gas is carried by the tube ,,kk to jars in a pneumato-chemical apparatus4 ,instead of the retort a funnel may be employed1 having its lower part shut by a stop-cock1 through which the water is allowed to drop gradually into the gun-barrel4 ,immediately upon getting into contact with the heated part of the iron1 the water is converted into steam1 and the experiment proceeds in the same manner as if it were furnished in vapours from the retort4 ,in the experiment made by ,mr ,meusnier and me before a committee of the ,academy1 we used every precaution to obtain the greatest possible precision in the result of our experiment1 having even exhausted all the vessels employed before we began1 so that the hydrogen gas obtained might be free from any mixture of azotic gas4 ,the results of that experiment will hereafter be given at large in a particular memoir4 ,in numerous experiments1 we are obliged to use tubes of glass1 porcelain1 or copper1 instead of gun-barrels2 but glass has the disadvantage of being easily melted and flattened1 if the heat be in the smallest degree raised too high2 and porcelain is mostly full of small minute pores1 through which the gas escapes1 especially when compressed by a column of water4 ,for these reasons ,i procured a tube of brass1 which ,mr de la ,briche got cast and bored out of the solid for me at ,strasburg1 under his own inspection4 ,this tube is extremely convenient for decomposing alkohol1 which resolves into charcoal1 carbonic acid gas1 and hydrogen gas2 it may likewise be used with the same advantage for decomposing water by means of charcoal1 and in a great number of experiments of this nature4 ,,footnotes3 #fj ,the representation of this apparatus1 ,pl4 ,,iv4 ,fig4 #a4 will convey a much better idea of its disposition than can possibly be given by the most laboured description4--,e4 ,,chap4 ,,vii4 ,of the ,composition and ,application of ,lutes4 ,the necessity of properly securing the junctures of chemical vessels to prevent the escape of any of the products of experiments1 must be sufficiently apparent2 for this purpose lutes are employed1 which ought to be of such a nature as to be equally impenetrable to the most subtile substances1 as glass itself1 through which only caloric can escape4 ,this first object of lutes is very well accomplished by bees wax1 melted with about an eighth part of turpentine4 ,this lute is very easily managed1 sticks very closely to glass1 and is very difficultly penetrable2 it may be rendered more consistent1 and less or more hard or pliable1 by adding different kinds of resinous matters4 ,though this species of lute answers extremely well for retaining gasses and vapours1 there are many chemical experiments which produce considerable heat1 by which this lute becomes liquified1 and consequently the expansive vapours must very readily force through and escape4 ,for such cases1 the following fat lute is the best hitherto discovered1 though not without its disadvantages1 which shall be pointed out4 ,take very pure and dry unbaked clay1 reduced to a very fine powder1 put this into a brass mortar1 and beat it for several hours with a heavy iron pestle1 dropping in slowly some boiled lintseed oil2 this is oil which has been oxygenated1 and has acquired a drying quality1 by being boiled with litharge4 ,this lute is more tenacious1 and applies better1 if amber varnish be used instead of the above oil4 ,to make this varnish1 melt some yellow amber in an iron laddle1 by which operation it loses a part of its succinic acid1 and essential oil1 and mix it with lintseed oil4 ,though the lute prepared with this varnish is better than that made with boiled oil1 yet1 as its additional expence is hardly compensated by its superior quality1 it is seldom used4 ,the above fat lute is capable of sustaining a very violent degree of heat1 is impenetrable by acids and spiritous liquors1 and adheres exceedingly well to metals1 stone ware1 or glass1 providing they have been previously rendered perfectly dry4 ,but if1 unfortunately1 any of the liquor in the course of an experiment gets through1 either between the glass and the lute1 or between the layers of the lute itself1 so as to moisten the part1 it is extremely difficult to close the opening4 ,this is the chief inconvenience which attends the use of fat lute1 and perhaps the only one it is subject to4 ,as it is apt to soften by heat1 we must surround all the junctures with slips of wet bladder applied over the luting1 and fixed on by pack-thread tied round both above and below the joint2 the bladder1 and consequently the lute below1 must be farther secured by a number of turns of pack-thread all over it4 ,by these precautions1 we are free from every danger of accident2 and the junctures secured in this manner may be considered1 in experiments1 as hermetically sealed4 ,it frequently happens that the figure of the junctures prevents the application of ligatures1 which is the case with the three-necked bottles formerly described2 and it even requires great address to apply the twine without shaking the apparatus2 so that1 where a number of junctures require luting1 we are apt to displace several while securing one4 ,in these cases1 we may substitute slips of linen1 spread with white of egg and lime mixed together1 instead of the wet bladder4 ,these are applied while still moist1 and very speedily dry and acquire considerable hardness4 ,strong glue dissolved in water may answer instead of white of egg4 ,these fillets are usefully applied likewise over junctures luted together with wax and rosin4 ,before applying a lute1 all the junctures of the vessels must be accurately and firmly fitted to each other1 so as not to admit of being moved4 ,if the beak of a retort is to be luted to the neck of a recipient1 they ought to fit pretty accurately2 otherwise we must fix them1 by introducing short pieces of soft wood or of cork4 ,if the disproportion between the two be very considerable1 we must employ a cork which fits the neck of the recipient1 having a circular hole of proper dimensions to admit the beak of the retort4 ,the same precaution is necessary in adapting bent tubes to the necks of bottles in the apparatus represented ,pl4 ,,iv4 ,fig4 #a4 and others of a similar nature4 ,each mouth of each bottle must be fitted with a cork1 having a hole made with a round file of a proper size for containing the tube4 ,and1 when one mouth is intended to admit two or more tubes1 which frequently happens when we have not a sufficient number of bottles with two or three necks1 we must use a cork with two or three holes1 ,pl4 ,,iv4 ,fig4 #h4 ,when the whole apparatus is thus solidly joined1 so that no part can play upon another1 we begin to lute4 ,the lute is softened by kneading and rolling it between the fingers1 with the assistance of heat1 if necessary4 ,it is rolled into little cylindrical pieces1 and applied to the junctures1 taking great care to make it apply close1 and adhere firmly1 in every part2 a second roll is applied over the first1 so as to pass it on each side1 and so on till each juncture be sufficiently covered2 after this1 the slips of bladder1 or of linen1 as above directed1 must be carefully applied over all4 ,though this operation may appear extremely simple1 yet it requires peculiar delicacy and management2 great care must be taken not to disturb one juncture whilst luting another1 and more especially when applying the fillets and ligatures4 ,before beginning any experiment1 the closeness of the luting ought always to be previously tried1 either by slightly heating the retort ,a1 ,pl4 ,,iv4 ,fig4 #a1 or by blowing in a little air by some of the perpendicular tubes ,s s s s2 the alteration of pressure causes a change in the level of the liquid in these tubes4 ,if the apparatus be accurately luted1 this alteration of level will be permanent2 whereas1 if there be the smallest1 opening in any of the junctures1 the liquid will very soon recover its former level4 ,it must always be remembered1 that the whole success of experiments in modern chemistry depends upon the exactness of this operation1 which therefore requires the utmost patience1 and most attentive accuracy4 ,it would be of infinite service to enable chemists1 especially those who are engaged in pneumatic processes1 to dispense with the use of lutes1 or at least to diminish the number necessary in complicated instruments4 ,i once thought of having my apparatus constructed so as to unite in all its parts by fitting with emery1 in the way of bottles with cristal stoppers2 but the execution of this plan was extremely difficult4 ,i have since thought it preferable to substitute columns of a few lines of mercury in place of lutes1 and have got an apparatus constructed upon this principle1 which appears capable of very convenient application in a great number of circumstances4 ,it consists of a double necked bottle ,a1 ,pl4 ,,xii4 ,fig4 #ab42 the interior neck bc communicates with the inside of the bottle1 and the exterior neck or rim de leaves an interval between the two necks1 forming a deep gutter intended to contain the mercury4 ,the cap or lid of glass ,b enters this gutter1 and is properly fitted to it1 having notches in its lower edge for the passage of the tubes which convey the gas4 ,these tubes1 instead of entering directly into the bottles as in the ordinary apparatus1 have a double bend for making them enter the gutter1 as represented in ,fig4 #ac4 and for making them fit the notches of the cap ,b2 they rise again from the gutter to enter the inside of the bottle over the border of the inner mouth4 ,when the tubes are disposed in their proper places1 and the cap firmly fitted on1 the gutter is filled with mercury1 by which means the bottle is completely excluded from any communication1 excepting through the tubes4 ,this apparatus may be very convenient in many operations in which the substances employed have no action upon ,mercury4 ,pl4 ,,xii4 ,fig4 #ad4 represents an apparatus upon this principle properly fitted together4 ,mr ,seguin1 to whose active and intelligent assistance ,i have been very frequently much indebted1 has bespoken for me1 at the glass-houses1 some retorts hermetically united to their recipients1 by which luting will be altogether unnecessary4 ,,chap4 ,,viii4 ,of ,operations upon ,combustion and ,deflagration4 ,,sect4 ,i4 ,of ,combustion in general4 ,combustion1 according to what has been already said in the ,first ,part of this ,work1 is the decomposition of oxygen gas produced by a combustible body4 ,the oxygen which forms the base of this gas is absorbed by1 and enters into1 combination with the burning body1 while the caloric and light are set free4 ,every combustion1 therefore1 necessarily supposes oxygenation2 whereas1 on the contrary1 every oxygenation does not necessarily imply concomitant combustion2 because combustion1 properly so called1 cannot take place without disengagement of caloric and light4 ,before combustion can take place1 it is necessary that the base of oxygen gas should have greater affinity to the combustible body than it has to caloric2 and this elective attraction1 to use ,bergman's expression1 can only take place at a certain degree of temperature1 which is different for each combustible substance2 hence the necessity of giving a first motion or beginning to every combustion by the approach of a heated body4 ,this necessity of heating any body we mean to burn depends upon certain considerations1 which have not hitherto been attended to by any natural philosopher1 for which reason ,i shall enlarge a little upon the subject in this place4 ,nature is at present in a state of equilibrium1 which cannot have been attained until all the spontaneous combustions or oxygenations possible in the ordinary degrees of temperature had taken place4 ,hence1 no new combustions or oxygenations can happen without destroying this equilibrium1 and raising the combustible substances to a superior degree of temperature4 ,to illustrate this abstract view of the matter by example3 ,let us suppose the usual temperature of the earth a little changed1 and that it is raised only to the degree of boiling water2 it is evident1 that1 in this case1 phosphorus1 which is combustible in a considerably lower degree of temperature1 would no longer exist in nature in its pure and simple state1 but would always be procured in its acid or oxygenated state1 and its radical would become one of the substances unknown to chemistry4 ,by gradually increasing the temperature of the earth the same circumstance would successively happen to all the bodies capable of combustion2 and1 at last1 every possible combustion having taken place1 there would no longer exist any combustible body whatever1 as every substance susceptible of that operation would be oxygenated1 and consequently incombustible4 ,there cannot therefore exist1 so far as relates to us1 any combustible body1 except such as are incombustible in the ordinary temperatures of the earth2 or1 what is the same thing1 in other words1 that it is essential to the nature of every combustible body not to possess the property of combustion1 unless heated1 or raised to the degree of temperature at which its combustion naturally takes place4 ,when this degree is once produced1 combustion commences1 and the caloric which is disengaged by the decomposition of the oxygen gas keeps up the temperature necessary for continuing combustion4 ,when this is not the case1 that is1 when the disengaged caloric is insufficient for keeping up the necessary temperature1 the combustion ceases3 ,this circumstance is expressed in common language by saying1 that a body burns ill1 or with difficulty4 ,although combustion possesses some circumstances in common with distillation1 especially with the compound kind of that operation1 they differ in a very material point4 ,in distillation there is a separation of one part of the elements of the substance from each other1 and a combination of these1 in a new order1 occasioned by the affinities which take place in the increased temperature produced during distillation3 ,this likewise happens in combustion1 but with this farther circumstance1 that a new element1 not originally in the body1 is brought into action2 oxygen is added to the substance submitted to the operation1 and caloric is disengaged4 ,the necessity of employing oxygen in the state of gas in all experiments with combustion1 and the rigorous determination of the quantities employed1 render this kind of operations peculiarly troublesome4 ,as almost all the products of combustion are disengaged in the state of gas1 it is still more difficult to retain them than even those furnished during compound distillation2 hence this precaution was entirely neglected by the ancient chemists2 and this set of experiments exclusively belong to modern chemistry4 ,having thus pointed out1 in a general way1 the objects to be had in view in experiments upon combustion1 ,i proceed1 in the following sections of this chapter1 to describe the different instruments ,i have used with this view4 ,the following arrangement is formed1 not upon the nature of the combustible bodies1 but upon that of the instruments necessary for combustion4 ,,sect4 ,,ii4 ,of the ,combustion of ,phosphorus4 ,in these combustions we begin by filling a jar1 capable at least of holding six pints1 with oxygen gas in the water apparatus1 ,pl4 ,v4 ,fig4 #a42 when it is perfectly full1 so that the gas begins to flow out below1 the jar1 ,a1 is carried to the mercury apparatus1 ,pl4 ,,iv4 ,fig4 #c4 ,we then dry the surface of the mercury1 both within and without the jar1 by means of blotting-paper1 taking care to keep the paper for some time entirely immersed in the mercury before it is introduced under the jar1 lest we let in any common air1 which sticks very obstinately to the surface of the paper4 ,the body to be submitted to combustion1 being first very accurately weighed in nice scales1 is placed in a small flat shallow dish1 ,d1 of iron or porcelain2 this is covered by the larger cup ,p1 which serves the office of a diving bell1 and the whole is passed through the mercury into the jar1 after which the larger cup is retired4 ,the difficulty of passing the materials of combustion in this manner through the mercury may be avoided by raising one of the sides of the jar1 ,a1 for a moment1 and slipping in the little cup1 ,d1 with the combustible body as quickly as possible4 ,in this manner of operating1 a small quantity of common air gets into the jar1 but it is so very inconsiderable as not to injure either the progress or accuracy of the experiment in any sensible degree4 ,when the cup1 ,d1 is introduced under the jar1 we suck out a part of the oxygen gas1 so as to raise the mercury to ,,ef1 as formerly directed1 ,part ,i4 ,chap4 ,v4 otherwise1 when the combustible body is set on fire1 the gas becoming dilated would be in part forced out1 and we should no longer be able to make any accurate calculation of the quantities before and after the experiment4 ,a very convenient mode of drawing out the air is by means of an air-pump syringe adapted to the syphon1 ,,ghi1 by which the mercury may be raised to any degree under twenty-eight inches4 ,very inflammable bodies1 as phosphorus1 are set on fire by means of the crooked iron wire1 ,,mn1 ,pl4 ,,iv4 ,fig4 #af4 made red hot1 and passed quickly through the mercury4 ,such as are less easily set on fire have a small portion of tinder1 upon which a minute particle of phosphorus is fixed1 laid upon them before using the red hot iron4 ,in the first moment of combustion the air1 being heated1 rarifies1 and the mercury descends2 but when1 as in combustions of phosphorus and iron1 no elastic fluid is formed1 absorption becomes presently very sensible1 and the mercury rises high into the jar4 ,great attention must be used not to burn too large a quantity of any substance in a given quantity of gas1 otherwise1 towards the end of the experiment1 the cup would approach so near the top of the jar as to endanger breaking it by the great heat produced1 and the sudden refrigeration from the cold mercury4 ,for the methods of measuring the volume of the gasses1 and for correcting the measures according to the heighth of the barometer and thermometer1 c4 see ,chap4 ,,ii4 ,sect4 ,v4 and ,,vi4 of this part4 ,the above process answers very well for burning all the concrete substances1 and even for the fixed oils3 ,these last are burnt in lamps under the jar1 and are readily set on fire by means of tinder1 phosphorus1 and hot iron4 ,but it is dangerous for substances susceptible of evaporating in a moderate heat1 such as ether1 alkohol1 and the essential oils2 these substances dissolve in considerable quantity in oxygen gas2 and1 when set on fire1 a dangerous and sudden explosion takes place1 which carries up the jar to a great height1 and dashes it in a thousand pieces4 ,from two such explosions some of the members of the ,academy and myself escaped very narrowly4 ,besides1 though this manner of operating is sufficient for determining pretty accurately the quantity of oxygen gas absorbed1 and of carbonic acid produced1 as water is likewise formed in all experiments upon vegetable and animal matters which contain an excess of hydrogen1 this apparatus can neither collect it nor determine its quantity4 ,the experiment with phosphorus is even incomplete in this way1 as it is impossible to demonstrate that the weight of the phosphoric acid produced is equal to the sum of the weights of the phosphorus burnt and oxygen gas absorbed during the process4 ,i have been therefore obliged to vary the instruments according to circumstances1 and to employ several of different kinds1 which ,i shall describe in their order1 beginning with that used for burning phosphorus4 ,take a large balloon1 ,a1 ,pl4 ,,iv4 ,fig4 #d4 of cristal or white glass1 with an opening1 ,,ef1 about two inches and a half1 or three inches1 diameter1 to which a cap of brass is accurately fitted with emery1 and which has two holes for the passage of the tubes xxx1 yyy4 ,before shutting the balloon with its cover1 place within it the stand1 ,,bc1 supporting the cup of porcelain1 ,d1 which contains the phosphorus4 ,then lute on the cap with fat lute1 and allow it to dry for some days1 and weigh the whole accurately2 after this exhaust the balloon by means of an air-pump connected with the tube xxx1 and fill it with oxygen gas by the tube yyy1 from the gazometer1 ,pl4 ,,viii4 ,fig4 #a4 described ,chap4 ,,ii4 ,sect ,,ii4 of this part4 ,the phosphorus is then set on fire by means of a burning-glass1 and is allowed to burn till the cloud of concrete phosphoric acid stops the combustion1 oxygen gas being continually supplied from the gazometer4 ,when the apparatus has cooled1 it is weighed and unluted2 the tare of the instrument being allowed1 the weight is that of the phosphoric acid contained4 ,it is proper1 for greater accuracy1 to examine the air or gas contained in the balloon after combustion1 as it may happen to be somewhat heavier or lighter than common air2 and this difference of weight must be taken into account in the calculations upon the results of the experiment4 ,,sect4 ,,iii4 ,of the ,combustion of ,charcoal4 ,the apparatus ,i have employed for this process consists of a small conical furnace of hammered copper1 represented in perspective1 ,pl4 ,,xii4 ,fig4 #i4 and internally displayed ,fig4 #aa4 ,it is divided into the furnace1 ,,abc1 where the charcoal is burnt1 the grate1 d e1 and the ash-hole1 ,f2 the tube1 ,,gh1 in the middle of the dome of the furnace serves to introduce the charcoal1 and as a chimney for carrying off the air which has served for combustion4 ,through the tube1 l m n1 which communicates with the gazometer1 the hydrogen gas1 or air1 intended for supporting the combustion1 is conveyed into the ash-hole1 ,f1 whence it is forced1 by the application of pressure to the gazometer1 to pass through the grate1 d e1 and to blow upon the burning charcoal placed immediately above4 ,oxygen gas1 which forms #bh_/ajj of atmospheric air1 is changed into carbonic acid gas during combustion with charcoal1 whilst the azotic gas of the air is not altered at all4 ,hence1 after the combustion of charcoal in atmospheric air1 a mixture of carbonic acid gas and azotic gas must remain2 to allow this mixture to pass off1 the tube1 o p1 is adapted to the chimney1 ,,gh1 by means of a screw at ,g1 and conveys the gas into bottles half filled with solution of caustic potash4 ,the carbonic acid gas is absorbed by the alkali1 and the azotic gas is conveyed into a second gazometer1 where its quantity is ascertained4 ,the weight of the furnace1 ,,abc1 is first accurately determined1 then introduce the tube ,,rs1 of known weight1 by the chimney1 ,,gh1 till its lower end ,s1 rests upon the grate1 d e1 which it occupies entirely2 in the next place1 fill the furnace with charcoal1 and weigh the whole again1 to know the exact quantity of charcoal submitted to experiment4 ,the furnace is now put in its place1 the tube1 l m n1 is screwed to that which communicates with the gazometer1 and the tube1 o p1 to that which communicates with the bottles of alkaline solution4 ,every thing being in readiness1 the stop-cock of the gazometer is opened1 a small piece of burning charcoal is thrown into the tube1 ,,rs1 which is instantly withdrawn1 and the tube1 o p1 is screwed to the chimney1 ,,gh4 ,the little piece of charcoal falls upon the grate1 and in this manner gets below the whole charcoal1 and is kept on fire by the stream of air from the gazometer4 ,to be certain that the combustion is begun1 and goes on properly1 the tube1 q r s1 is fixed to the furnace1 having a piece of glass cemented to its upper extremity1 s1 through which we can see if the charcoal be on fire4 ,i neglected to observe above1 that the furnace1 and its appendages1 are plunged in water in the cistern1 ,,tvxy1 ,fig4 #aa4 ,pl4 ,,xii4 to which ice may be added to moderate the heat1 if necessary2 though the heat is by no means very considerable1 as there is no air but what comes from the gazometer1 and no more of the charcoal burns at one time than what is immediately over the grate4 ,as one piece of charcoal is consumed another falls down into its place1 in consequence of the declivity of the sides of the furnace2 this gets into the stream of air from the grate1 d e1 and is burnt2 and so on1 successively1 till the whole charcoal is consumed4 ,the air which has served the purpose of the combustion passes through the mass of charcoal1 and is forced by the pressure of the gazometer to escape through the tube1 o p1 and to pass through the bottles of alkaline solution4 ,this experiment furnishes all the necessary data for a complete analysis of atmospheric air and of charcoal4 ,we know the weight of charcoal consumed2 the gazometer gives us the measure of the air employed2 the quantity and quality of gas remaining after combustion may be determined1 as it is received1 either in another gazometer1 or in jars1 in a pneumato-chemical apparatus2 the weight of ashes remaining in the ash-hole is readily ascertained2 and1 finally1 the additional weight acquired by the bottles of alkaline solution gives the exact quantity of carbonic acid formed during the process4 ,by this experiment we may likewise determine1 with sufficient accuracy1 the proportions in which charcoal and oxygen enter into the composition of carbonic acid4 ,in a future memoir ,i shall give an account to the ,academy of a series of experiments ,i have undertaken1 with this instrument1 upon all the vegetable and animal charcoals4 ,by some very slight alterations1 this machine may be made to answer for observing the principal phenomena of respiration4 ,,sect4 ,,iv4 ,of the ,combustion of ,oils4 ,oils are more compound in their nature than charcoal1 being formed by the combination of at least two elements1 charcoal and hydrogen2 of course1 after their combustion in common air1 water1 carbonic acid gas1 and azotic gas1 remain4 ,hence the apparatus employed for their combustion requires to be adapted for collecting these three products1 and is consequently more complicated than the charcoal furnace4 ,the apparatus ,i employ for this purpose is composed of a large jar or pitcher ,a1 ,pl4 ,,xii4 ,fig4 #d4 surrounded at its upper edge by a rim of iron properly cemented at ,,de1 and receding from the jar at ,,bc1 so as to leave a furrow or gutter xx1 between it and the outside of the jar1 somewhat more than two inches deep4 ,the cover or lid of the jar1 ,fig4 #e4 is likewise surrounded by an iron rim f g1 which adjusts into the gutter xx1 ,fig4 #d4 which being filled with mercury1 has the effect of closing the jar hermetically in an instant1 without using any lute2 and1 as the gutter will hold about two inches of mercury1 the air in the jar may be made to sustain the pressure of more than two feet of water1 without danger of its escaping4 ,the lid has four holes1 ,t h i k1 for the passage of an equal number of tubes4 ,the opening ,t is furnished with a leather box1 through which passes the rod1 ,fig4 #c4 intended for raising and lowering the wick of the lamp1 as will be afterwards directed4 ,the three other holes are intended for the passage of three several tubes1 one of which conveys the oil to the lamp1 a second conveys air for keeping up the combustion1 and the third carries off the air1 after it has served for combustion4 ,the lamp in which the oil is burnt is represented ,fig4 #b2 a is the reservoir of oil1 having a funnel by which it is filled2 b c d e f g h is a syphon which conveys the oil to the lamp #aa2 #g1 #h1 #i1 #aj1 is the tube which conveys the air for combustion from the gazometer to the same lamp4 ,the tube b c is formed externally1 at its lower end b1 into a male screw1 which turns in a female screw in the lid of the reservoir of oil a2 so that1 by turning the reservoir one way or the other1 it is made to rise or fall1 by which the oil is kept at the necessary level4 ,when the syphon is to be filled1 and the communication formed between the reservoir of oil and the lamp1 the stop-cock c is shut1 and that at e opened1 oil is poured in by the opening f at the top of the syphon1 till it rises within three or four lines of the upper edge of the lamp1 the stop-cock k is then shut1 and that at c opened2 the oil is then poured in at f1 till the branch b c d of the syphon is filled1 and then the stop-cock e is closed4 ,the two branches of the syphon being now completely filled1 a communication is fully established between the reservoir and the lamp4 ,in ,pl4 ,,xii4 ,fig4 #a4 all the parts of the lamp #aa1 ,fig4 #b4 are represented magnified1 to show them distinctly4 ,the tube i k carries the oil from the reservoir to the cavity a a a a1 which contains the wick2 the tube #i1 #aj1 brings the air from the gazometer for keeping up the combustion2 this air spreads through the cavity d d d d1 and1 by means of the passages c c c c and b b b b1 is distributed on each side of the wick1 after the principles of the lamps constructed by ,argand1 ,quinquet1 and ,lange4 ,to render the whole of this complicated apparatus more easily understood1 and that its description may make all others of the same kind more readily followed1 it is represented1 completely connected together for use1 in ,pl4 ,,xi4 ,the gazometer ,p furnishes air for the combustion by the tube and stop-cock #a1 #b2 the tube #b1 #c1 communicates with a second gazometer1 which is filled whilst the first one is emptying during the process1 that there may be no interruption to the combustion2 #d1 #e1 is a tube of glass filled with deliquescent salts1 for drying the air as much as possible in its passage2 and the weight of this tube and its contained salts1 at the beginning of the experiment1 being known1 it is easy to determine the quantity of water absorbed by them from the air4 ,from this deliquescent tube the air is conducted through the pipe #e1 #f1 #g1 #h1 #i1 #aj1 to the lamp #aa1 where it spreads on both sides of the wick1 as before described1 and feeds the flame4 ,one part of this air1 which serves to keep up the combustion of the oil1 forms carbonic acid gas and water1 by oxygenating its elements4 ,part of this water condenses upon the sides of the pitcher ,a1 and another part is held in solution in the air by means of caloric furnished by the combustion4 ,this air is forced by the compression of the gazometer to pass through the tube #ab1 #ac1 #ad1 #ae1 into the bottle #af1 and the worm #ag1 #ah1 where the water is fully condensed from the refrigeration of the air2 and1 if any water still remains in solution1 it is absorbed by deliquescent salts contained in the tube #ai1 #bj4 ,all these precautions are solely intended for collecting and determining the quantity of water formed during the experiment2 the carbonic acid and azotic gas remains to be ascertained4 ,the former is absorbed by caustic alkaline solution in the bottles #bb and #be4 ,i have only represented two of these in the figure1 but nine at least are requisite2 and the last of the series may be half filled with lime-water1 which is the most certain reagent for indicating the presence of carbonic acid2 if the lime-water is not rendered turbid1 we may be certain that no sensible quantity of that acid remains in the air4 ,the rest of the air which has served for combustion1 and which chiefly consists of azotic gas1 though still mixed with a considerable portion of oxygen gas1 which has escaped unchanged from the combustion1 is carried through a third tube #bh1 #bi1 of deliquescent salts1 to deprive it of any moisture it may have acquired in the bottles of alkaline solution and lime-water1 and from thence by the tube #bi1 #cj1 into a gazometer1 where its quantity is ascertained4 ,small essays are then taken from it1 which are exposed to a solution of sulphuret of potash1 to ascertain the proportions of oxygen and azotic gas it contains4 ,in the combustion of oils the wick becomes charred at last1 and obstructs the rise of the oil2 besides1 if we raise the wick above a certain height1 more oil rises through its capillary tubes than the stream of air is capable of consuming1 and smoke is produced4 ,hence it is necessary to be able to lengthen or shorten the wick without opening the apparatus2 this is accomplished by means of the rod #ca1 #cb1 #cc1 #cd1 which passes through a leather-box1 and is connected with the support of the wick2 and that the motion of this rod1 and consequently of the wick1 may be regulated with the utmost smoothness and facility2 it is moved at pleasure by a pinnion which plays in a toothed rack4 ,the rod1 with its appendages1 are represented ,pl4 ,,xii4 ,fig4 #c4 ,it appeared to me1 that the combustion would be assisted by surrounding the flame of the lamp with a small glass jar open at both ends1 as represented in its place in ,pl4 ,,xi4 ,i shall not enter into a more detailed description of the construction of this apparatus1 which is still capable of being altered and modified in many respects1 but shall only add1 that when it is to be used in experiment1 the lamp and reservoir with the contained oil must be accurately weighed1 after which it is placed as before directed1 and lighted2 having then formed the connection between the air in the gazometer and the lamp1 the external jar ,a1 ,pl4 ,,xi4 is fixed over all1 and secured by means of the board ,,bc and two rods of iron which connect this board with the lid1 and are screwed to it4 ,a small quantity of oil is burnt while the jar is adjusting to the lid1 and the product of that combustion is lost2 there is likewise a small portion of air from the gazometer lost at the same time4 ,both of these are of very inconsiderable consequence in extensive experiments1 and they are even capable of being valued in our calculation of the results4 ,in a particular memoir1 ,i shall give an account to the ,academy of the difficulties inseparable from this kind of experiments3 ,these are so insurmountable and troublesome1 that ,i have not hitherto been able to obtain any rigorous determination of the quantities of the products4 ,i have sufficient proof1 however1 that the fixed oils are entirely resolved during combustion into water and carbonic acid gas1 and consequently that they are composed of hydrogen and charcoal2 but ,i have no certain knowledge respecting the proportions of these ingredients4 ,,sect4 ,v4 ,of the ,combustion of ,alkohol4 ,the combustion of alkohol may be very readily performed in the apparatus already described for the combustion of charcoal and phosphorus4 ,a lamp filled with alkohol is placed under the jar ,a1 ,pl4 ,,iv4 ,fig4 #c4 a small morsel of phosphorus is placed upon the wick of the lamp1 which is set on fire by means of the hot iron1 as before directed4 ,this process is1 however1 liable to considerable inconveniency2 it is dangerous to make use of oxygen gas at the beginning of the experiment for fear of deflagration1 which is even liable to happen when common air is employed4 ,an instance of this had very near proved fatal to myself1 in presence of some members of the ,academy4 ,instead of preparing the experiment1 as usual1 at the time it was to be performed1 ,i had disposed every thing in order the evening before2 the atmospheric air of the jar had thereby sufficient time to dissolve a good deal of the alkohol2 and this evaporation had even been considerably promoted by the height of the column of mercury1 which ,i had raised to ,,ef1 ,pl4 ,,iv4 ,fig4 #c4 ,the moment ,i attempted to set the little morsel of phosphorus on fire by means of the red hot iron1 a violent explosion took place1 which threw the jar with great violence against the floor of the laboratory1 and dashed it in a thousand pieces4 ,hence we can only operate upon very small quantities1 such as ten or twelve grains of alkohol1 in this manner2 and the errors which may be committed in experiments upon such small quantities prevents our placing any confidence in their results4 ,i endeavoured to prolong the combustion1 in the experiments contained in the ,memoirs of the ,academy for #aghd1 p4 #eic4 by lighting the alkohol first in common air1 and furnishing oxygen gas afterwards to the jar1 in proportion as it consumed2 but the carbonic acid gas produced by the process became a great hinderance to the combustion1 the more so that alkohol is but difficultly combustible1 especially in worse than common air2 so that even in this way very small quantities only could be burnt4 ,perhaps this combustion might succeed better in the oil apparatus1 ,pl4 ,,xi42 but ,i have not hitherto ventured to try it4 ,the jar ,a in which the combustion is performed is near #adjj cubical inches in dimension2 and1 were an explosion to take place in such a vessel1 its consequences would be very terrible1 and very difficult to guard against4 ,i have not1 however1 despaired of making the attempt4 ,from all these difficulties1 ,i have been hitherto obliged to confine myself to experiments upon very small quantities of alkohol1 or at least to combustions made in open vessels1 such as that represented in ,pl4 ,,ix4 ,fig4 #e4 which will be described in ,section ,,vii4 of this chapter4 ,if ,i am ever able to remove these difficulties1 ,i shall resume this investigation4 ,,sect4 ,,vi4 ,of the ,combustion of ,ether4 ,tho' the combustion of ether in close vessels does not present the same difficulties as that of alkohol1 yet it involves some of a different kind1 not more easily overcome1 and which still prevent the progress of my experiments4 ,i endeavoured to profit by the property which ether possesses of dissolving in atmospheric air1 and rendering it inflammable without explosion4 ,for this purpose1 ,i constructed the reservoir of ether a b c d1 ,plate ,,xii4 ,fig4 #h4 to which air is brought from the gazometer by the tube #a1 #b1 #c1 #d4 ,this air spreads1 in the first place1 in the double lid ac of the reservoir1 from which it passes through seven tubes ef1 gh1 ik1 c4 which descend to the bottom of the ether1 and it is forced by the pressure of the gazometer to boil up through the ether in the reservoir4 ,we may replace the ether in this first reservoir1 in proportion as it is dissolved and carried off by the air1 by means of the supplementary reservoir ,e1 connected by a brass tube fifteen or eighteen inches long1 and shut by a stop-cock4 ,this length of the connecting tube is to enable the descending ether to overcome the resistance occasioned by the pressure of the air from the gazometer4 ,the air1 thus loaded with vapours of ether1 is conducted by the tube #e1 #f1 #g1 #h1 #i1 to the jar ,a1 into which it is allowed to escape through a capillary opening1 at the extremity of which it is set on fire4 ,the air1 when it has served the purpose of combustion1 passes through the bottle #af1 ,pl4 ,,xi4 the worm #ag1 #ah1 and the deliquescent tube #ai1 #bj1 after which it passes through the alkaline bottles2 in these its carbonic acid gas is absorbed1 the water formed during the experiment having been previously deposited in the former parts of the apparatus4 ,when ,i caused construct this apparatus1 ,i supposed that the combination of atmospheric air and ether formed in the reservoir a b c d1 ,pl4 ,,xii4 ,fig4 #h4 was in proper proportion for supporting combustion2 but in this ,i was mistaken2 for there is a very considerable quantity of excess of ether2 so that an additional quantity of atmospheric air is necessary to enable it to burn fully4 ,hence a lamp constructed upon these principles will burn in common air1 which furnishes the quantity of oxygen necessary for combustion1 but will not burn in close vessels in which the air is not renewed4 ,from this circumstance1 my ether lamp went out soon after being lighted and shut up in the jar ,a1 ,pl4 ,,xii4 ,fig4 #h4 ,to remedy this defect1 ,i endeavoured to bring atmospheric air to the lamp by the lateral tube #aj1 #aa1 #ab1 #ac1 #ad1 #ae1 which ,i distributed circularly round the flame2 but the flame is so exceedingly rare1 that it is blown out by the gentlest possible stream of air1 so that ,i have not hitherto succeeded in burning ether4 ,i do not1 however1 despair of being able to accomplish it by means of some changes ,i am about to have made upon this apparatus4 ,,sect4 ,,vii4 ,of the ,combustion of ,hydrogen ,gas1 and the ,formation of ,water4 ,in the formation of water1 two substances1 hydrogen and oxygen1 which are both in the ariform state before combustion1 are transformed into liquid or water by the operation4 ,this experiment would be very easy1 and would require very simple instruments1 if it were possible to procure the two gasses perfectly pure1 so that they might burn without any residuum4 ,we might1 in that case1 operate in very small vessels1 and1 by continually furnishing the two gasses in proper proportions1 might continue the combustion indefinitely4 ,but1 hitherto1 chemists have only employed oxygen gas1 mixed with azotic gas2 from which circumstance1 they have only been able to keep up the combustion of hydrogen gas for a very limited time in close vessels1 because1 as the residuum of azotic gas is continually increasing1 the air becomes at last so much contaminated1 that the flame weakens and goes out4 ,this inconvenience is so much the greater in proportion as the oxygen gas employed is less pure4 ,from this circumstance1 we must either be satisfied with operating upon small quantities1 or must exhaust the vessels at intervals1 to get rid of the residuum of azotic gas2 but1 in this case1 a portion of the water formed during the experiment is evaporated by the exhaustion2 and the resulting error is the more dangerous to the accuracy of the process1 that we have no certain means of valuing it4 ,these considerations make me desirous to repeat the principal experiments of pneumatic chemistry with oxygen gas entirely free from any admixture of azotic gas2 and this may be procured from oxygenated muriat of potash4 ,the oxygen gas extracted from this salt does not appear to contain azote1 unless accidentally1 so that1 by proper precautions1 it may be obtained perfectly pure4 ,in the mean time1 the apparatus employed by ,mr ,meusnier and me for the combustion of hydrogen gas1 which is described in the experiment for recomposition of water1 ,part ,i4 ,chap4 ,,viii4 and need not be here repeated1 will answer the purpose2 when pure gasses are procured1 this apparatus will require no alterations1 except that the capacity of the vessels may then be diminished4 ,see ,pl4 ,,iv4 ,fig4 #e4 ,the combustion1 when once begun1 continues for a considerable time1 but weakens gradually1 in proportion as the quantity of azotic gas remaining from the combustion increases1 till at last the azotic gas is in such over proportion that the combustion can no longer be supported1 and the flame goes out4 ,this spontaneous extinction must be prevented1 because1 as the hydrogen gas is pressed upon in its reservoir1 by an inch and a half of water1 whilst the oxygen gas suffers a pressure only of three lines1 a mixture of the two would take place in the balloon1 which would at last be forced by the superior pressure into the reservoir of oxygen gas4 ,wherefore the combustion must be stopped1 by shutting the stop-cock of the tube d,dd whenever the flame grows very feeble2 for which purpose it must be attentively watched4 ,there is another apparatus for combustion1 which1 though we cannot with it perform experiments with the same scrupulous exactness as with the preceding instruments1 gives very striking results that are extremely proper to be shewn in courses of philosophical chemistry4 ,it consists of a worm ,,ef1 ,pl4 ,,ix4 ,fig4 #e4 contained in a metallic cooller ,,abcd4 ,to the upper part of this worm ,e1 the chimney ,,gh is fixed1 which is composed of two tubes1 the inner of which is a continuation of the worm1 and the outer one is a case of tin-plate1 which surrounds it at about an inch distance1 and the interval is filled up with sand4 ,at the inferior extremity ,k of the inner tube1 a glass tube is fixed1 to which we adopt the ,argand lamp ,,lm for burning alkohol1 c4 ,things being thus disposed1 and the lamp being filled with a determinate quantity of alkohol1 it is set on fire2 the water which is formed during the combustion rises in the chimney ,,ke1 and being condensed in the worm1 runs out at its extremity ,f into the bottle ,p4 ,the double tube of the chimney1 filled with sand in the interstice1 is to prevent the tube from cooling in its upper part1 and condensing the water2 otherwise1 it would fall back in the tube1 and we should not be able to ascertain its quantity1 and besides it might fall in drops upon the wick1 and extinguish the flame4 ,the intention of this construction1 is to keep the chimney always hot1 and the worm always cool1 that the water may be preserved in the state of vapour whilst rising1 and may be condensed immediately upon getting into the descending part of the apparatus4 ,by this instrument1 which was contrived by ,mr ,meusnier1 and which is described by me in the ,memoirs of the ,academy for #aghd1 p4 #eic4 we may1 with attention to keep the worm always cold1 collect nearly seventeen ounces of water from the combustion of sixteen ounces of alkohol4 ,,sect4 ,,viii4 ,of the ,oxydation of ,metals4 ,the term oxydation or calcination is chiefly used to signify the process by which metals exposed to a certain degree of heat are converted into oxyds1 by absorbing oxygen from the air4 ,this combination takes place in consequence of oxygen possessing a greater affinity to metals1 at a certain temperature1 than to caloric1 which becomes disengaged in its free state2 but1 as this disengagement1 when made in common air1 is slow and progressive1 it is scarcely evident to the senses4 ,it is quite otherwise1 however1 when oxydation takes place in oxygen gas2 for1 being produced with much greater rapidity1 it is generally accompanied with heat and light1 so as evidently to show that metallic substances are real combustible bodies4 ,all the metals have not the same degree of affinity to oxygen4 ,gold1 silver1 and platina1 for instance1 are incapable of taking it away from its combination with caloric1 even in the greatest known heat2 whereas the other metals absorb it in a larger or smaller quantity1 until the affinities of the metal to oxygen1 and of the latter to caloric1 are in exact equilibrium4 ,indeed1 this state of equilibrium of affinities may be assumed as a general law of nature in all combinations4 ,in all operations of this nature1 the oxydation of metals is accelerated by giving free access to the air2 it is sometimes much assisted by joining the action of a bellows1 which directs a stream of air over the surface of the metal4 ,this process becomes greatly more rapid if a stream of oxygen gas be used1 which is readily done by means of the gazometer formerly described4 ,the metal1 in this case1 throws out a brilliant flame1 and the oxydation is very quickly accomplished2 but this method can only be used in very confined experiments1 on account of the expence of procuring oxygen gas4 ,in the essay of ores1 and in all the common operations of the laboratory1 the calcination or oxydation of metals is usually performed in a dish of baked clay1 ,pl4 ,,iv4 ,fig4 #f4 commonly called a roasting test1 placed in a strong furnace4 ,the substances to be oxydated are frequently stirred1 on purpose to present fresh surfaces to the air4 ,whenever this operation is performed upon a metal which is not volatile1 and from which nothing flies off into the surrounding air during the process1 the metal acquires additional weight2 but the cause of this increased weight during oxydation could never have been discovered by means of experiments performed in free air2 and it is only since these operations have been performed in close vessels1 and in determinate quantities of air1 that any just conjectures have been formed concerning the cause of this phenomenon4 ,the first method for this purpose is due to ,dr ,priestley1 who exposes the metal to be calcined in a porcelain cup ,n1 ,pl4 ,,iv4 ,fig4 #aa4 placed upon the stand ,,ik1 under a jar ,a1 in the bason ,,bcde1 full of water2 the water is made to rise up to ,,gh1 by sucking out the air with a syphon1 and the focus of a burning glass is made to fall upon the metal4 ,in a few minutes the oxydation takes place1 a part of the oxygen contained in the air combines with the metal1 and a proportional diminution of the volume of air is produced2 what remains is nothing more than azotic gas1 still however mixed with a small quantity of oxygen gas4 ,i have given an account of a series of experiments made with this apparatus in my ,physical and ,chemical ,essays1 first published in #aggc4 ,mercury may be used instead of water in this experiment1 whereby the results are rendered still more conclusive4 ,another process for this purpose was invented by ,mr ,boyle1 and of which ,i gave an account in the ,memoirs of the ,academy for #aggd1 p4 #cea4 ,the metal is introduced into a retort1 ,pl4 ,,iii4 ,fig4 #bj4 the beak of which is hermetically sealed2 the metal is then oxydated by means of heat applied with great precaution4 ,the weight of the vessel1 and its contained substances1 is not at all changed by this process1 until the extremity of the neck of the retort is broken2 but1 when that is done1 the external air rushes in with a hissing noise4 ,this operation is attended with danger1 unless a part of the air is driven out of the retort1 by means of heat1 before it is hermetically sealed1 as otherwise the retort would be apt to burst by the dilation of the air when placed in the furnace4 ,the quantity of air driven out may be received under a jar in the pneumato-chemical apparatus1 by which its quantity1 and that of the air remaining in the retort1 is ascertained4 ,i have not multiplied my experiments upon oxydation of metals so much as ,i could have wished2 neither have ,i obtained satisfactory results with any metal except tin4 ,it is much to be wished that some person would undertake a series of experiments upon oxydation of metals in the several gasses2 the subject is important1 and would fully repay any trouble which this kind of experiment might occasion4 ,as all the oxyds of mercury are capable of revivifying without addition1 and restore the oxygen gas they had before absorbed1 this seemed to be the most proper metal for becoming the subject of conclusive experiments upon oxydation4 ,i formerly endeavoured to accomplish the oxydation of mercury in close vessels1 by filling a retort1 containing a small quantity of mercury1 with oxygen gas1 and adapting a bladder half full of the same gas to its beak2 ,see ,pl4 ,,iv4 ,fig4 #ab4 ,afterwards1 by heating the mercury in the retort for a very long time1 ,i succeeded in oxydating a very small portion1 so as to form a little red oxyd floating upon the surface of the running mercury2 but the quantity was so small1 that the smallest error committed in the determination of the quantities of oxygen gas before and after the operation must have thrown very great uncertainty upon the results of the experiment4 ,i was1 besides1 dissatisfied with this process1 and not without cause1 lest any air might have escaped through the pores of the bladder1 more especially as it becomes shrivelled by the heat of the furnace1 unless covered over with cloths kept constantly wet4 ,this experiment is performed with more certainty in the apparatus described in the ,memoirs of the ,academy for #agge1 p4 #ehj4 ,this consists of a retort1 ,a1 ,pl4 ,,iv4 ,fig4 #b4 having a crooked glass tube ,,bcde of ten or twelve lines internal diameter1 melted on to its beak1 and which is engaged under the bell glass ,,fg1 standing with its mouth downwards1 in a bason filled with water or mercury4 ,the retort is placed upon the bars of the furnace ,,mmnn1 ,pl4 ,,iv4 ,fig4 #b4 or in a sand bath1 and by means of this apparatus we may1 in the course of several days1 oxydate a small quantity of mercury in common air2 the red oxyd floats upon the surface1 from which it may be collected and revivified1 so as to compare the quantity of oxygen gas obtained in revivification with the absorption which took place during oxydation4 ,this kind of experiment can only be performed upon a small scale1 so that no very certain conclusions can be drawn from them#fa4 ,the combustion of iron in oxygen gas being a true oxydation of that metal1 ought to be mentioned in this place4 ,the apparatus employed by ,mr ,ingenhousz for this operation is represented in ,pl4 ,,iv4 ,fig4 #ag42 but1 having already described it sufficiently in ,chap4 ,,iii4 ,i shall refer the reader to what is said of it in that place4 ,iron may likewise be oxydated by combustion in vessels filled with oxygen gas1 in the way already directed for phosphorus and charcoal4 ,this apparatus is represented ,pl4 ,,iv4 ,fig4 #c4 and described in the fifth chapter of the first part of this work4 ,we learn from ,mr ,ingenhousz1 that all the metals1 except gold1 silver1 and mercury1 may be burnt or oxydated in the same manner1 by reducing them into very fine wire1 or very thin plates cut into narrow slips2 these are twisted round with iron-wire1 which communicates the property of burning to the other metals4 ,mercury is even difficultly oxydated in free air4 ,in chemical laboratories1 this process is usually carried on in a matrass ,a1 ,pl4 ,,iv4 ,fig4 having a very flat body1 and a very long neck ,,bc1 which vessel is commonly called ,boyle's bell4 ,a quantity of mercury is introduced sufficient to cover the bottom1 and it is placed in a sand-bath1 which keeps up a constant heat approaching to that of boiling mercury4 ,by continuing this operation with five or six similar matrasses during several months1 and renewing the mercury from time to time1 a few ounces of red oxyd are at last obtained4 ,the great slowness and inconvenience of this apparatus arises from the air not being sufficiently renewed2 but if1 on the other hand1 too free a circulation were given to the external air1 it would carry off the mercury in solution in the state of vapour1 so that in a few days none would remain in the vessel4 ,as1 of all the experiments upon the oxydation of metals1 those with mercury are the most conclusive1 it were much to be wished that a simple apparatus could be contrived by which this oxydation and its results might be demonstrated in public courses of chemistry4 ,this might1 in my opinion1 be accomplished by methods similar to those ,i have already described for the combustion of charcoal and the oils2 but1 from other pursuits1 ,i have not been able hitherto to resume this kind of experiment4 ,the oxyd of mercury revives without addition1 by being heated to a slightly red heat4 ,in this degree of temperature1 oxygen has greater affinity to caloric than to mercury1 and forms oxygen gas4 ,this is always mixed with a small portion of azotic gas1 which indicates that the mercury absorbs a small portion of this latter gas during oxydation4 ,it almost always contains a little carbonic acid gas1 which must undoubtedly be attributed to the foulnesses of the oxyd2 these are charred by the heat1 and convert a part of the oxygen gas into carbonic acid4 ,if chemists were reduced to the necessity of procuring all the oxygen gas employed in their experiments from mercury oxydated by heat without addition1 or1 as it is called1 calcined or precipitated per se1 the excessive dearness of that preparation would render experiments1 even upon a moderate scale1 quite impracticable4 ,but mercury may likewise be oxydated by means of nitric acid2 and in this way we procure a red oxyd1 even more pure than that produced by calcination4 ,i have sometimes prepared this oxyd by dissolving mercury in nitric acid1 evaporating to dryness1 and calcining the salt1 either in a retort1 or in capsules formed of pieces of broken matrasses and retorts1 in the manner formerly described2 but ,i have never succeeded in making it equally beautiful with what is sold by the druggists1 and which is1 ,i believe1 brought from ,holland4 ,in choosing this1 we ought to prefer what is in solid lumps composed of soft adhering scales1 as when in powder it is sometimes adulterated with red oxyd of lead4 ,to obtain oxygen gas from the red oxyd of mercury1 ,i usually employ a porcelain retort1 having a long glass tube adapted to its beak1 which is engaged under jars in the water pneumato-chemical apparatus1 and ,i place a bottle in the water1 at the end of the tube1 for receiving the mercury1 in proportion as it revives and distils over4 ,as the oxygen gas never appears till the retort becomes red1 it seems to prove the principle established by ,mr ,berthollet1 that an obscure heat can never form oxygen gas1 and that light is one of its constituent elements4 ,we must reject the first portion of gas which comes over1 as being mixed with common air1 from what was contained in the retort at the beginning of the experiment2 but1 even with this precaution1 the oxygen gas procured is usually contaminated with a tenth part of azotic gas1 and with a very small portion of carbonic acid gas4 ,this latter is readily got rid of1 by making the gas pass through a solution of caustic alkali2 but we know of no method for separating the azotic gas2 its proportions may however be ascertained1 by leaving a known quantity of the oxygen gas contaminated with it for a fortnight1 in contact with sulphuret of soda or potash1 which absorbs the oxygen gas so as to convert the sulphur into sulphuric acid1 and leaves the azotic gas remaining pure4 ,we may likewise procure oxygen gas from black oxyd of manganese or nitrat of potash1 by exposing them to a red heat in the apparatus already described for operating upon red oxyd of mercury2 only1 as it requires such a heat as is at least capable of softening glass1 we must employ retorts of stone or of porcelain4 ,but the purest and best oxygen gas is what is disengaged from oxygenated muriat of potash by simple heat4 ,this operation is performed in a glass retort1 and the gas obtained is perfectly pure1 provided that the first portions1 which are mixed with the common air of the vessels1 be rejected4 ,,footnotes3 #fa ,see an account of this experiment1 ,part4 ,i4 ,chap4 iii4--,a4 ,,chap4 ,,ix4 ,of ,deflagration4 ,i have already shown1 ,part ,i4 ,chap4 ,,ix4 that oxygen does not always part with the whole of the caloric it contained in the state of gas when it enters into combination with other bodies4 ,it carries almost the whole of its caloric alongst with it in entering into the combinations which form nitric acid and oxygenated muriatic acid2 so that in nitrats1 and more especially in oxygenated muriats1 the oxygen is1 in a certain degree1 in the state of oxygen gas1 condensed1 and reduced to the smallest volume it is capable of occupying4 ,in these combinations1 the caloric exerts a constant action upon the oxygen to bring it back to the state of gas2 hence the oxygen adheres but very slightly1 and the smallest additional force is capable of setting it free2 and1 when such force is applied1 it often recovers the state of gas instantaneously4 ,this rapid passage from the solid to the ariform state is called detonation1 or fulmination1 because it is usually accompanied with noise and explosion4 ,deflagrations are commonly produced by means of combinations of charcoal either with nitre or oxygenated muriat of potash2 sometimes1 to assist the inflammation1 sulphur is added2 and1 upon the just proportion of these ingredients1 and the proper manipulation of the mixture1 depends the art of making gun-powder4 ,as oxygen is changed1 by deflagration with charcoal1 into carbonic acid1 instead of oxygen gas1 carbonic acid gas is disengaged1 at least when the mixture has been made in just proportions4 ,in deflagration with nitre1 azotic gas is likewise disengaged1 because azote is one of the constituent elements of nitric acid4 ,the sudden and instantaneous disengagement and expansion of these gasses is not1 however1 sufficient for explaining all the phenomena of deflagration2 because1 if this were the sole operating power1 gun powder would always be so much the stronger in proportion as the quantity of gas disengaged in a given time was the more considerable1 which does not always accord with experiment4 ,i have tried some kinds which produced almost double the effect of ordinary gun powder1 although they gave out a sixth part less of gas during deflagration4 ,it would appear that the quantity of caloric disengaged at the moment of detonation contributes considerably to the expansive effects produced2 for1 although caloric penetrates freely through the pores of every body in nature1 it can only do so progressively1 and in a given time2 hence1 when the quantity disengaged at once is too large to get through the pores of the surrounding bodies1 it must necessarily act in the same way with ordinary elastic fluids1 and overturn every thing that opposes its passage4 ,this must1 at least in part1 take place when gun-powder is set on fire in a cannon2 as1 although the metal is permeable to caloric1 the quantity disengaged at once is too large to find its way through the pores of the metal1 it must therefore make an effort to escape on every side2 and1 as the resistance all around1 excepting towards the muzzle1 is too great to be overcome1 this effort is employed for expelling the bullet4 ,the caloric produces a second effect1 by means of the repulsive force exerted between its particles2 it causes the gasses1 disengaged at the moment of deflagration1 to expand with a degree of force proportioned to the temperature produced4 ,it is very probable that water is decomposed during the deflagration of gun-powder1 and that part of the oxygen furnished to the nascent carbonic acid gas is produced from it4 ,if so1 a considerable quantity of hydrogen gas must be disengaged in the instant of deflagration1 which expands1 and contributes to the force of the explosion4 ,it may readily be conceived how greatly this circumstance must increase the effect of powder1 if we consider that a pint of hydrogen gas weighs only one grain and two thirds2 hence a very small quantity in weight must occupy a very large space1 and it must exert a prodigious expansive force in passing from the liquid to the ariform state of existence4 ,in the last place1 as a portion of undecomposed water is reduced to vapour during the deflagration of gun-powder1 and as water1 in the state of gas1 occupies seventeen or eighteen hundred times more space than in its liquid state1 this circumstance must likewise contribute largely to the explosive force of the powder4 ,i have already made a considerable series of experiments upon the nature of the elastic fluids disengaged during the deflagration of nitre with charcoal and sulphur2 and have made some1 likewise1 with the oxygenated muriat of potash4 ,this method of investigation leads to tollerably accurate conclusions with respect to the constituent elements of these salts4 ,some of the principal results of these experiments1 and of the consequences drawn from them respecting the analysis of nitric acid1 are reported in the collection of memoirs presented to the ,academy by foreign philosophers1 vol4 xi4 p4 #fbe4 ,since then ,i have procured more convenient instruments1 and ,i intend to repeat these experiments upon a larger scale1 by which ,i shall procure more accurate precision in their results2 the following1 however1 is the process ,i have hitherto employed4 ,i would very earnestly advise such as intend to repeat some of these experiments1 to be very much upon their guard in operating upon any mixture which contains nitre1 charcoal1 and sulphur1 and more especially with those in which oxygenated muriat of potash is mixed with these two materials4 ,i make use of pistol barrels1 about six inches long1 and of five or six lines diameter1 having the touch-hole spiked up with an iron nail strongly driven in1 and broken in the hole1 and a little tin-smith's solder run in to prevent any possible issue for the air4 ,these are charged with a mixture of known quantities of nitre and charcoal1 or any other mixture capable of deflagration1 reduced to an impalpable powder1 and formed into a paste with a moderate quantity of water4 ,every portion of the materials introduced must be rammed down with a rammer nearly of the same caliber with the barrel1 four or five lines at the muzzle must be left empty1 and about two inches of quick match are added at the end of the charge4 ,the only difficulty in this experiment1 especially when sulphur is contained in the mixture1 is to discover the proper degree of moistening2 for1 if the paste be too much wetted1 it will not take fire1 and if too dry1 the deflagration is apt to become too rapid1 and even dangerous4 ,when the experiment is not intended to be rigorously exact1 we set fire to the match1 and1 when it is just about to communicate with the charge1 we plunge the pistol below a large bell-glass full of water1 in the pneumato chemical apparatus4 ,the deflagration begins1 and continues in the water1 and gas is disengaged with less or more rapidity1 in proportion as the mixture is more or less dry4 ,so long as the deflagration continues1 the muzzle of the pistol must be kept somewhat inclined downwards1 to prevent the water from getting into its barrel4 ,in this manner ,i have sometimes collected the gas produced from the deflagration of an ounce and half1 or two ounces1 of nitre4 ,in this manner of operating it is impossible to determine the quantity of carbonic acid gas disengaged1 because a part of it is absorbed by the water while passing through it2 but1 when the carbonic acid is absorbed1 the azotic gas remains2 and1 if it be agitated for a few minutes in caustic alkaline solution1 we obtain it pure1 and can easily determine its volume and weight4 ,we may even1 in this way1 acquire a tollerably exact knowledge of the quantity of carbonic acid by repeating the experiment a great many times1 and varying the proportions of charcoal1 till we find the exact quantity requisite to deflagrate the whole nitre employed4 ,hence1 by means of the weight of charcoal employed1 we determine the weight of oxygen necessary for saturation1 and deduce the quantity of oxygen contained in a given weight of nitre4 ,i have used another process1 by which the results of this experiment are considerably more accurate1 which consists in receiving the disengaged gasses in bell-glasses filled with mercury4 ,the mercurial apparatus ,i employ is large enough to contain jars of from twelve to fifteen pints in capacity1 which are not very readily managed when full of mercury1 and even require to be filled by a particular method4 ,when the jar is placed in the cistern of mercury1 a glass syphon is introduced1 connected with a small air-pump1 by means of which the air is exhausted1 and the mercury rises so as to fill the jar4 ,after this1 the gas of the deflagration is made to pass into the jar in the same manner as directed when water is employed4 ,i must again repeat1 that this species of experiment requires to be performed with the greatest possible precautions4 ,i have sometimes seen1 when the disengagement of gas proceeded with too great rapidity1 jars filled with more than an hundred and fifty pounds of mercury driven off by the force of the explosion1 and broken to pieces1 while the mercury was scattered about in great quantities4 ,when the experiment has succeeded1 and the gas is collected under the jar1 its quantity in general1 and the nature and quantities of the several species of gasses of which the mixture is composed1 are accurately ascertained by the methods already pointed out in the second chapter of this part of my work4 ,i have been prevented from putting the last hand to the experiments ,i had begun upon deflagration1 from their connection with the objects ,i am at present engaged in2 and ,i am in hopes they will throw considerable light upon the operations belonging to the manufacture of gun-powder4 ,,chap4 ,x4 ,of the ,instruments necessary for ,operating upon ,bodies in very high ,temperatures4 ,,sect4 ,i4 ,of ,fusion4 ,we have already seen1 that1 by aqueous solution1 in which the particles of bodies are separated from each other1 neither the solvent nor the body held in solution are at all decomposed2 so that1 whenever the cause of separation ceases1 the particles reunite1 and the saline substance recovers precisely the same appearance and properties it possessed before solution4 ,real solutions are produced by fire1 or by introducing and accumulating a great quantity of caloric between the particles of bodies2 and this species of solution in caloric is usually called fusion4 ,this operation is commonly performed in vessels called crucibles1 which must necessarily be less fusible than the bodies they are intended to contain4 ,hence1 in all ages1 chemists have been extremely solicitous to procure crucibles of very refractory materials1 or such as are capable of resisting a very high degree of heat4 ,the best are made of very pure clay or of porcelain earth2 whereas such as are made of clay mixed with calcareous or silicious earth are very fusible4 ,all the crucibles made in the neighbourhood of ,paris are of this kind1 and consequently unfit for most chemical experiments4 ,the ,hessian crucibles are tolerably good2 but the best are made of ,limoges earth1 which seems absolutely infusible4 ,we have1 in ,france1 a great many clays very fit for making crucibles2 such1 for instance1 is the kind used for making melting pots at the glass-manufactory of ,st ,gobin4 ,crucibles are made of various forms1 according to the operations they are intended to perform4 ,several of the most common kinds are represented ,pl4 ,,vii4 ,fig4 #g4 #h4 #i4 and #aj4 the one represented at ,fig4 #i4 is almost shut at its mouth4 ,though fusion may often take place without changing the nature of the fused body1 this operation is frequently employed as a chemical means of decomposing and recompounding bodies4 ,in this way all the metals are extracted from their ores2 and1 by this process1 they are revivified1 moulded1 and alloyed with each other4 ,by this process sand and alkali are combined to form glass1 and by it likewise pastes1 or coloured stones1 enamels1 c4 are formed4 ,the action of violent fire was much more frequently employed by the ancient chemists than it is in modern experiments4 ,since greater precision has been employed in philosophical researches1 the humid has been preferred to the dry method of process1 and fusion is seldom had recourse to until all the other means of analysis have failed4 ,,sect4 ,,ii4 ,of ,furnaces4 ,these are instruments of most universal use in chemistry2 and1 as the success of a great number of experiments depends upon their being well or ill constructed1 it is of great importance that a laboratory be well provided in this respect4 ,a furnace is a kind of hollow cylindrical tower1 sometimes widened above1 ,pl4 ,,xiii4 ,fig4 #a4 ,,abcd1 which must have at least two lateral openings2 one in its upper part ,f1 which is the door of the fire-place1 and one below1 ,g1 leading to the ash-hole4 ,between these the furnace is divided by a horizontal grate1 intended for supporting the fewel1 the situation of which is marked in the figure by the line ,,hi4 ,though this be the least complicated of all the chemical furnaces1 yet it is applicable to a great number of purposes4 ,by it lead1 tin1 bismuth1 and1 in general1 every substance which does not require a very strong fire1 may be melted in crucibles2 it will serve for metallic oxydations1 for evaporatory vessels1 and for sand-baths1 as in ,pl4 ,,iii4 ,fig4 #a4 and #b4 ,to render it proper for these purposes1 several notches1 m m m m1 ,pl4 ,,xiii4 ,fig4 #a4 are made in its upper edge1 as otherwise any pan which might be placed over the fire would stop the passage of the air1 and prevent the fewel from burning4 ,this furnace can only produce a moderate degree of heat1 because the quantity of charcoal it is capable of consuming is limited by the quantity of air which is allowed to pass through the opening ,g of the ash-hole4 ,its power might be considerably augmented by enlarging this opening1 but then the great stream of air which is convenient for some operations might be hurtful in others2 wherefore we must have furnaces of different forms1 constructed for different purposes1 in our laboratories3 ,there ought especially to be several of the kind now described of different sizes4 ,the reverberatory furnace1 ,pl4 ,,xiii4 ,fig4 #b4 is perhaps more necessary4 ,this1 like the common furnace1 is composed of the ash-hole ,,hikl1 the fire-place ,,klmn1 the laboratory ,,mnop1 and the dome ,,rrss1 with its funnel or chimney ,,ttvv2 and to this last several additional tubes may be adapted1 according to the nature of the different experiments4 ,the retort ,a is placed in the division called the laboratory1 and supported by two bars of iron which run across the furnace1 and its beak comes out at a round hole in the side of the furnace1 one half of which is cut in the piece called the laboratory1 and the other in the dome4 ,in most of the ready made reverberatory furnaces which are sold by the potters at ,paris1 the openings both above and below are too small3 ,these do not allow a sufficient volume of air to pass through2 hence1 as the quantity of charcoal consumed1 or1 what is much the same thing1 the quantity of caloric disengaged1 is nearly in proportion to the quantity of air which passes through the furnace1 these furnaces do not produce a sufficient effect in a great number of experiments4 ,to remedy this defect1 there ought to be two openings ,,gg to the ash-hole2 one of these is shut up when only a moderate fire is required2 and both are kept open when the strongest power of the furnace is to be exerted4 ,the opening of the dome ,,ss ought likewise to be considerably larger than is usually made4 ,it is of great importance not to employ retorts of too large size in proportion to the furnace1 as a sufficient space ought always to be allowed for the passage of the air between the sides of the furnace and the vessel4 ,the retort ,a in the figure is too small for the size of the furnace1 yet ,i find it more easy to point out the error than to correct it4 ,the intention of the dome is to oblige the flame and heat to surround and strike back or reverberate upon every part of the retort1 whence the furnace gets the name of reverberatory4 ,without this circumstance the retort would only be heated in its bottom1 the vapours raised from the contained substance would condense in the upper part1 and a continual cohabitation would take place without any thing passing over into the receiver1 but1 by means of the dome1 the retort is equally heated in every part1 and the vapours being forced out1 can only condense in the neck of the retort1 or in the recipient4 ,to prevent the bottom of the retort from being either heated or coolled too suddenly1 it is sometimes placed in a small sand-bath of baked clay1 standing upon the cross bars of the furnace4 ,likewise1 in many operations1 the retorts are coated over with lutes1 some of which are intended to preserve them from the too sudden influence of heat or of cold1 while others are for sustaining the glass1 or forming a kind of second retort1 which supports the glass one during operations wherein the strength of the fire might soften it4 ,the former is made of brick-clay with a little cow's hair beat up alongst with it1 into a paste or mortar1 and spread over the glass or stone retorts4 ,the latter is made of pure clay and pounded stone-ware mixed together1 and used in the same manner4 ,this dries and hardens by the fire1 so as to form a true supplementary retort capable of retaining the materials1 if the glass retort below should crack or soften4 ,but1 in experiments which are intended for collecting gasses1 this lute1 being porous1 is of no manner of use4 ,in a great many experiments wherein very violent fire is not required1 the reverberatory furnace may be used as a melting one1 by leaving out the piece called the laboratory1 and placing the dome immediately upon the fire-place1 as represented ,pl4 ,,xiii4 ,fig4 #c4 ,the furnace represented in ,fig4 #d4 is very convenient for fusions2 it is composed of the fire-place and ash-hole ,,abd1 without a door1 and having a hole ,e1 which receives the muzzle of a pair of bellows strongly luted on1 and the dome ,,abgh1 which ought to be rather lower than is represented in the figure4 ,this furnace is not capable of producing a very strong heat1 but is sufficient for ordinary operations1 and may be readily moved to any part of the laboratory where it is wanted4 ,though these particular furnaces are very convenient1 every laboratory must be provided with a forge furnace1 having a good pair of bellows1 or1 what is more necessary1 a powerful melting furnace4 ,i shall describe the one ,i use1 with the principles upon which it is constructed4 ,the air circulates in a furnace in consequence of being heated in its passage through the burning coals2 it dilates1 and1 becoming lighter than the surrounding air1 is forced to rise upwards by the pressure of the lateral columns of air1 and is replaced by fresh air from all sides1 especially from below4 ,this circulation of air even takes place when coals are burnt in a common chaffing dish2 but we can readily conceive1 that1 in a furnace open on all sides1 the mass of air which passes1 all other circumstances being equal1 cannot be so great as when it is obliged to pass through a furnace in the shape of a hollow tower1 like most of the chemical furnaces1 and consequently1 that the combustion must be more rapid in a furnace of this latter construction4 ,suppose1 for instance1 the furnace ,,abcdef open above1 and filled with burning coals1 the force with which the air passes through the coals will be in proportion to the difference between the specific gravity of two columns equal to ,,ac1 the one of cold air without1 and the other of heated air within the furnace4 ,there must be some heated air above the opening ,,ab1 and the superior levity of this ought likewise to be taken into consideration2 but1 as this portion is continually coolled and carried off by the external air1 it cannot produce any great effect4 ,but1 if we add to this furnace a large hollow tube ,,ghab of the same diameter1 which preserves the air which has been heated by the burning coals from being coolled and dispersed by the surrounding air1 the difference of specific gravity which causes the circulation will then be between two columns equal to ,,gc4 ,hence1 if ,,gc be three times the length of ,,ac1 the circulation will have treble force4 ,this is upon the supposition that the air in ,,ghcd is as much heated as what is contained in ,,abcd1 which is not strictly the case1 because the heat must decrease between ,,ab and ,,gh2 but1 as the air in ,,ghab is much warmer than the external air1 it follows1 that the addition of the tube must increase the rapidity of the stream of air1 that a larger quantity must pass through the coals1 and consequently that a greater degree of combustion must take place4 ,we must not1 however1 conclude from these principles1 that the length of this tube ought to be indefinitely prolonged2 for1 since the heat of the air gradually diminishes in passing from ,,ab to ,,gh1 even from the contact of the sides of the tube1 if the tube were prolonged to a certain degree1 we would at last come to a point where the specific gravity of the included air would be equal to the air without2 and1 in this case1 as the cool air would no longer tend to rise upwards1 it would become a gravitating mass1 resisting the ascension of the air below4 ,besides1 as this air1 which has served for combustion1 is necessarily mixed with carbonic acid gas1 which is considerably heavier than common air1 if the tube were made long enough1 the air might at last approach so near to the temperature of the external air as even to gravitate downwards2 hence we must conclude1 that the length of the tube added to a furnace must have some limit beyond which it weakens1 instead of strengthening the force of the fire4 ,from these reflections it follows1 that the first foot of tube added to a furnace produces more effect than the sixth1 and the sixth more than the tenth2 but we have no data to ascertain at what height we ought to stop4 ,this limit of useful addition is so much the farther in proportion as the materials of the tube are weaker conductors of heat1 because the air will thereby be so much less coolled2 hence baked earth is much to be preferred to plate iron4 ,it would be even of consequence to make the tube double1 and to fill the interval with rammed charcoal1 which is one of the worst conductors of heat known2 by this the refrigeration of the air will be retarded1 and the rapidity of the stream of air consequently increased2 and1 by this means1 the tube may be made so much the longer4 ,as the fire-place is the hottest part of a furnace1 and the part where the air is most dilated in its passage1 this part ought to be made with a considerable widening or belly4 ,this is the more necessary1 as it is intended to contain the charcoal and crucible1 as well as for the passage of the air which supports1 or rather produces the combustion2 hence we only allow the interstices between the coals for the passage of the air4 ,from these principles my melting furnace is constructed1 which ,i believe is at least equal in power to any hitherto made1 though ,i by no means pretend that it possesses the greatest possible intensity that can be produced in chemical furnaces4 ,the augmentation of the volume of air produced during its passage through a melting furnace not being hitherto ascertained from experiment1 we are still unacquainted with the proportions which should exist between the inferior and superior apertures1 and the absolute size of which these openings should be made is still less understood2 hence data are wanting by which to proceed upon principle1 and we can only accomplish the end in view by repeated trials4 ,this furnace1 which1 according to the above stated rules1 is in form of an eliptical spheroid1 is represented ,pl4 ,,xiii4 ,fig4 #f4 ,,abcd2 it is cut off at the two ends by two plains1 which pass1 perpendicular to the axis1 through the foci of the elipse4 ,from this shape it is capable of containing a considerable quantity of charcoal1 while it leaves sufficient space in the intervals for the passage of the air4 ,that no obstacle may oppose the free access of external air1 it is perfectly open below1 after the model of ,mr ,macquer's melting furnace1 and stands upon an iron tripod4 ,the grate is made of flat bars set on edge1 and with considerable interstices4 ,to the upper part is added a chimney1 or tube1 of baked earth1 ,,abfg1 about eighteen feet long1 and almost half the diameter of the furnace4 ,though this furnace produces a greater heat than any hitherto employed by chemists1 it is still susceptible of being considerably increased in power by the means already mentioned1 the principal of which is to render the tube as bad a conductor of heat as possible1 by making it double1 and filling the interval with rammed charcoal4 ,when it is required to know if lead contains any mixture of gold or silver1 it is heated in a strong fire in capsules of calcined bones1 which are called cuppels4 ,the lead is oxydated1 becomes vitrified1 and sinks into the substance of the cuppel1 while the gold or silver1 being incapable of oxydation1 remain pure4 ,as lead will not oxydate without free access of air1 this operation cannot be performed in a crucible placed in the middle of the burning coals of a furnace1 because the internal air1 being mostly already reduced by the combustion into azotic and carbonic acid gas1 is no longer fit for the oxydation of metals4 ,it was therefore necessary to contrive a particular apparatus1 in which the metal should be at the same time exposed to the influence of violent heat1 and defended from contact with air rendered incombustible by its passage through burning coals4 ,the furnace intended for answering this double purpose is called the cuppelling or essay furnace4 ,it is usually made of a square form1 as represented ,pl4 ,,xiii4 ,fig4 #h4 and #aj4 having an ash-hole ,,aabb1 a fire-place ,,bbcc1 a laboratory ,,ccdd1 and a dome ,,ddee4 ,the muffle or small oven of baked earth ,,gh1 ,fig4 #i4 being placed in the laboratory of the furnace upon cross bars of iron1 is adjusted to the opening ,,gg1 and luted with clay softened in water4 ,the cuppels are placed in this oven or muffle1 and charcoal is conveyed into the furnace through the openings of the dome and fire-place4 ,the external air enters through the openings of the ash-hole for supporting the combustion1 and escapes by the superior opening or chimney at ,,ee2 and air is admitted through the door of the muffle ,,gg for oxydating the contained metal4 ,very little reflection is sufficient to discover the erroneous principles upon which this furnace is constructed4 ,when the opening ,,gg is shut1 the oxydation is produced slowly1 and with difficulty1 for want of air to carry it on2 and1 when this hole is open1 the stream of cold air which is then admitted fixes the metal1 and obstructs the process4 ,these inconveniencies may be easily remedied1 by constructing the muffle and furnace in such a manner that a stream of fresh external air should always play upon the surface of the metal1 and this air should be made to pass through a pipe of clay kept continually red hot by the fire of the furnace4 ,by this means the inside of the muffle will never be coolled1 and processes will be finished in a few minutes1 which at present require a considerable space of time4 ,mr ,sage remedies these inconveniencies in a different manner2 he places the cuppel containing lead1 alloyed with gold or silver1 amongst the charcoal of an ordinary furnace1 and covered by a small porcelain muffle2 when the whole is sufficiently heated1 he directs the blast of a common pair of hand-bellows upon the surface of the metal1 and completes the cuppellation in this way with great ease and exactness4 ,,sect4 ,,iii4 ,of increasing the ,action of ,fire1 by using ,oxygen ,gas instead of ,atmospheric ,air4 ,by means of large burning glasses1 such as those of ,tchirnausen and ,mr de ,trudaine1 a degree of heat is obtained somewhat greater than has hitherto been produced in chemical furnaces1 or even in the ovens of furnaces used for baking hard porcelain4 ,but these instruments are extremely expensive1 and do not even produce heat sufficient to melt crude platina2 so that their advantages are by no means sufficient to compensate for the difficulty of procuring1 and even of using them4 ,concave mirrors produce somewhat more effect than burning glasses of the same diameter1 as is proved by the experiments of ,messrs ,macquer and ,beaum with the speculum of the ,abb ,bouriot2 but1 as the direction of the reflected rays is necessarily from below upwards1 the substance to be operated upon must be placed in the air without any support1 which renders most chemical experiments impossible to be performed with this instrument4 ,for these reasons1 ,i first endeavoured to employ oxygen gas for combustion1 by filling large bladders with it1 and making it pass through a tube capable of being shut by a stop-cock2 and in this way ,i succeeded in causing it to support the combustion of lighted charcoal4 ,the intensity of the heat produced1 even in my first attempt1 was so great as readily to melt a small quantity of crude platina4 ,to the success of this attempt is owing the idea of the gazometer1 described p4 #cjh4 et seq4 which ,i substituted instead of the bladders2 and1 as we can give the oxygen gas any necessary degree of pressure1 we can with this instrument keep up a continued stream1 and give it even a very considerable force4 ,the only apparatus necessary for experiments of this kind consists of a small table ,,abcd1 ,pl4 ,,xii4 ,fig4 #ae1 with a hole ,f1 through which passes a tube of copper or silver1 ending in a very small opening at ,g1 and capable of being opened or shut by the stop-cock ,h4 ,this tube is continued below the table at l m n o1 and is connected with the interior cavity of the gazometer4 ,when we mean to operate1 a hole of a few lines deep must be made with a chizel in a piece of charcoal1 into which the substance to be treated is laid2 the charcoal is set on fire by means of a candle and blow-pipe1 after which it is exposed to a rapid stream of oxygen gas from the extremity ,g of the tube ,,fg4 ,this manner of operating can only be used with such bodies as can be placed1 without inconvenience1 in contact with charcoal1 such as metals1 simple earths1 c4 ,but1 for bodies whose elements have affinity to charcoal1 and which are consequently decomposed by that substance1 such as sulphats1 phosphats1 and most of the neutral salts1 metallic glasses1 enamels1 c4 we must use a lamp1 and make the stream of oxygen gas pass through its flame4 ,for this purpose1 we use the elbowed blow-pipe ,,st1 instead of the bent one ,,fg1 employed with charcoal4 ,the heat produced in this second manner is by no means so intense as in the former way1 and is very difficultly made to melt platina4 ,in this manner of operating with the lamp1 the substances are placed in cuppels of calcined bones1 or little cups of porcelain1 or even in metallic dishes4 ,if these last are sufficiently large1 they do not melt1 because1 metals being good conductors of heat1 the caloric spreads rapidly through the whole mass1 so that none of its parts are very much heated4 ,in the ,memoirs of the ,academy for #aghb1 p4 #dgf4 and for #aghc1 p4 #egc4 the series of experiments ,i have made with this apparatus may be seen at large4 ,the following are some of the principal results4 #a4 ,rock cristal1 or pure silicious earth1 is infusible1 but becomes capable of being softened or fused when mixed with other substances4 #b4 ,lime1 magnesia1 and barytes1 are infusible1 either when alone1 or when combined together2 but1 especially lime1 they assist the fusion of every other body4 #c4 ,argill1 or pure base of alum1 is completely fusible per se into a very hard opake vitreous substance1 which scratches glass like the precious stones4 #d4 ,all the compound earths and stones are readily fused into a brownish glass4 #e4 ,all the saline substances1 even fixed alkali1 are volatilized in a few seconds4 #f4 ,gold1 silver1 and probably platina1 are slowly volatilized without any particular phenomenon4 #g4 ,all other metallic substances1 except mercury1 become oxydated1 though placed upon charcoal1 and burn with different coloured flames1 and at last dissipate altogether4 #h4 ,the metallic oxyds likewise all burn with flames4 ,this seems to form a distinctive character for these substances1 and even leads me to believe1 as was suspected by ,bergman1 that barytes is a metallic oxyd1 though we have not hitherto been able to obtain the metal in its pure or reguline state4 #i4 ,some of the precious stones1 as rubies1 are capable of being softened and soldered together1 without injuring their colour1 or even diminishing their weights4 ,the hyacinth1 tho' almost equally fixed with the ruby1 loses its colour very readily4 ,the ,saxon and ,brasilian topaz1 and the ,brasilian ruby1 lose their colour very quickly1 and lose about a fifth of their weight1 leaving a white earth1 resembling white quartz1 or unglazed china4 ,the emerald1 chrysolite1 and garnet1 are almost instantly melted into an opake and coloured glass4 #aj4 ,the diamond presents a property peculiar to itself2 it burns in the same manner with combustible bodies1 and is entirely dissipated4 ,there is yet another manner of employing oxygen gas for considerably increasing the force of fire1 by using it to blow a furnace4 ,mr ,achard first conceived this idea2 but the process he employed1 by which he thought to dephlogisticate1 as it is called1 atmospheric air1 or to deprive it of azotic gas1 is absolutely unsatisfactory4 ,i propose to construct a very simple furnace1 for this purpose1 of very refractory earth1 similar to the one represented ,pl4 ,,xiii4 ,fig4 #d4 but smaller in all its dimensions4 ,it is to have two openings1 as at ,e1 through one of which the nozle of a pair of bellows is to pass1 by which the heat is to be raised as high as possible with common air2 after which1 the stream of common air from the bellows being suddenly stopt1 oxygen gas is to be admitted by a tube1 at the other opening1 communicating with a gazometer having the pressure of four or five inches of water4 ,i can in this manner unite the oxygen gas from several gazometers1 so as to make eight or nine cubical feet of gas pass through the furnace2 and in this way ,i expect to produce a heat greatly more intense than any hitherto known4 ,the upper orifice of the furnace must be carefully made of considerable dimensions1 that the caloric produced may have free issue1 lest the too sudden expansion of that highly elastic fluid should produce a dangerous explosion4 ,,finis4 ,,appendix4 ,no4 ,i4 ,,table for ,converting ,lines1 or ,twelfth ,parts of an ,inch1 and ,fractions of ,lines1 into ,decimal ,fractions of the ,inch4 ,twelfth ,parts ,decimal ,decimal of a ,line4 ,fractions4 ,lines4 ,fractions4 #a #j4jjfid #a #j4jhccc #b #j4jachi #b #j4afffg #c #j4jbjhc #c #j4bejjj #d #j4jbggh #d #j4ccccc #e #j4jcdgb #e #j4daffg #f #j4jdafg #f #j4ejjjj #g #j4jdhfa #g #j4ehccc #h #j4jeeef #h #j4ffffg #i #j4jfbej #i #j4gejjj #aj #j4jfidd #aj #j4hcccc #aa #j4jgfci #aa #j4iaffg #ab #j4jhccc #ab #a4jjjjj ,no4 ,,ii4 ,,table for ,converting the ,observed ,heighths of ,water in the ,jars of the ,pneumato-,chemical ,apparatus1 expressed in ,inches and ,decimals1 into ,corresponding ,heighths of ,mercury4 ,water4 ,mercury4 ,water4 ,mercury4 4#a 4#jjgcg #d4 4#bidhj 4#b 4#jadgd #e4 4#cfhea 4#c 4#jbbja #f4 4#ddbba 4#d 4#jbidh #g4 4#eaeia 4#e 4#jcfhe #h4 4#ehifa 4#f 4#jddbb #i4 4#ffccb 4#g 4#jeaei #aj4 4#gcgjb 4#h 4#jehif #aa4 4#hajgb 4#i 4#jffcc #ab4 4#hhddb #a4 4#jgcgj #ac4 4#ifhab #b4 4#adgdj #ad4 #a4jdahb #c4 4#bbjaj #ae4 #a4aaebe ,no4 ,,iii4 ,,table for ,converting the ,ounce ,measures used by ,dr ,priestly into ,french and ,english ,cubical ,inches4 ,ounce ,french cubical ,english cubical measures4 inches4 inches4 #a #a4efg #a4hih #b #c4acd #c4gif #c #d4gja #e4fid #d #f4bfh #g4eib #e #g4hce #i4dij #f #i4djb #aa4chh #g #aj4ifi #ac4bhf #h #ab4ecf #ae4ahd #i #ad4ajc #ag4jhb #aj #ae4fgj #ah4ihj #bj #ca4cdj #cg4ifj #cj #dg4jaj #ef4idj #dj #fb4fhj #ge4ibj #ej #gh4cej #id4ijj #fj #id4jbj #aac4hhj #gj #aji4fij #acb4hfj #hj #abe4cfj #aea4hdj #ij #ada4jcj #agj4hbj #ajj #aef4gjj #ahi4hjj #ajjj #aefg4jjj #ahih4jjj ,no4 ,,iv4 ,,additional4 ,,table for ,reducing the ,degrees of ,reaumeur's ,thermometer into its corresponding ,degrees of ,fahrenheit's ,scale4 ,r4 ,f4 ,r4 ,f4 ,r4 ,f4 ,r4 ,f4 #j #cb #ba #gi4be #da #abd4be #fa #afi4be #a #cd4be #bb #ha4e #db #abf4e #fb #aga4e #b #cf4e #bc #hc4ge #dc #abh4ge #fc #agc4ge #c #ch4ge #bd #hf #dd #aca #fd #agf4 #d #da #be #hh4be #de #acc4be #fe #agh4be #e #dc4be #bf #ij4e #df #ace4e #ff #ahj4e #f #de4e #bg #ib4ge #dg #acg4ge #fg #ahb4ge #g #dg4ge #bh #ie #dh #adj #fh #ahe #h #ej #bi #ig4be #di #adb4be #fi #ahg4be #i #eb4be #cj #ii4e #ej #add4e #gj #ahi4e #aj #ed4e #ca #aja4ge #ea #adf4ge #ga #aia4ge #aa #ef4ge #cb #ajd #eb #adi #gb #aid4 #ab #ei #cc #ajf4be #ec #aea4be #gc #aif4be #ac #fa4be #cd #ajh4e #ed #aec4e #gd #aih4e #ad #fc4e #ce #aaj4ge #ee #aee4ge #ge #bjj4ge #ae #fe4ge #cf #aac #ef #aeh #gf #bjc #af #fh #cg #aae4be #eg #afj4be #gg #bje4be #ag #gj4be #ch #aag4e #eh #afb4e #gh #bjg4e #ah #gb4e #ci #aai4ge #ei #afd4ge #gi #bji4ge #ai #gd4ge #dj #abb #fj #afg #hj #bab #bj #gg ,note--,any degree1 either higher or lower1 than what is contained in the above ,table1 may be at any time converted1 by remembering that one degree of ,reaumeur's scale is equal to #b4be of ,fahrenheit2 or it may be done without the ,table by the following formula1 ,r #i _/ #d #cb ,f2 that is1 multiply the degree of ,reaumeur by #i1 divide the product by #d1 to the quotient add #cb1 and the sum is the degree of ,fahrenheit4--,e4 ,no4 ,v4 ,,additional4 ,,rules for converting ,french ,weights and ,measures into correspondent ,english ,denominations#fb4 #a4 ,weights4 ,the ,paris pound1 poids de mark of ,charlemagne1 contains #ibaf ,paris grains2 it is divided into #af ounces1 each ounce into #h gros1 and each gros into #gb grains4 ,it is equal to #gefa ,english ,troy grains4 ,the ,english ,troy pound of #ab ounces contains #egfj ,english ,troy grains1 and is equal to #gjba ,paris grains4 ,the ,english averdupois pound of #af ounces contains #gjjj ,english ,troy grains1 and is equal to #hech ,paris grains4 ,to reduce ,paris grs4 to ,english ,troy grs4 divide by #a4bahi ,to reduce ,english ,troy grs4 to ,paris grs4 multiply by ,to reduce ,paris ounces to ,english ,troy1 divide by ,to reduce ,english ,troy ounces to #a4jaegcd ,paris1 multiply by ,or the conversion may be made by means of the following ,tables4 ,i4 ,to reduce ,french to ,english ,troy ,weight4 ,the ,paris pound #gefa ,the ounce #dgb4efbe ,english4 ,the gros #ei4jgjc ,troy4 ,the grain 4#haid ,grains4 ,,ii4 ,to ,reduce ,english ,troy to ,paris ,weight4 ,the ,english ,troy pound #gjba4 of #ab ounces ,the ,troy ounce #ehe4jhcj ,the dram of #fj grs4 #gc4acec ,paris ,the penny weight1 or #bi4bedj grains4 denier1 of #bd grs4 ,the scruple1 of #bj grs4 #bd4cghd ,,iii4 ,to ,reduce ,english ,averdupois to ,paris ,weight4 ,the averdupois pound of #af ounces1 or #gjjj #hech4 ,paris ,troy grains4 grains4 ,the ounce #ecc4fbej #b4 ,long and ,cubical ,measures4 ,to reduce ,paris feet or inches into ,english1 multiply by #a4jfeigg ,english feet or inches into ,paris1 divide by ,to reduce ,paris cubic feet or inches to ,english1 multiply by ,english cubic feet or inches to ,paris1 #a4baabgh divide by ,or by means of the following tables3 ,,iv4 ,to ,reduce ,paris ,long ,measure to ,english4 ,the ,paris royal foot of #ab inches #ab4gigg ,english ,the inch #a4jfei ,the line1 or #a_/ab of an inch 4#jhhh inches4 ,the #a_/ab of a line 4#jjgd ,v4 ,to ,reduce ,english ,long ,measure to ,french4 ,the ,english foot #aa4beif ,the inch 4#ichc ,the #a_/h of an inch 4#aagc ,paris inches4 ,the #a_/aj 4#jich ,the line1 or #a_/ab 4#jghb ,,vi4 ,to ,reduce ,french ,cube ,measure to ,english4 ,the ,paris ,english cube foot #a4baabgh cubical #bjic4jhhchd ,the cubic feet1 inches4 inch 4#jjjgjj or #a4baabgh ,,vii4 ,to ,reduce ,english ,cube ,measure to ,french4 ,the ,english cube foot1 or #agbh cubical inches #adbg4dhfd ,french ,the cubical inch 4#hbfj cubical ,the cube tenth 4#jjjh inches4 #c4 ,measure of ,capacity4 ,the ,paris pint contains #eh4adefc ,english cubical inches1 and the ,english wine pint contains #bh4he cubical inches2 or1 the ,paris pint contains #b4jaejh ,english pints1 and the ,english pint contains 4#difag ,paris pints2 hence1 ,to reduce the ,paris pint to the ,english1 multiply by #b4jaejh4 ,to reduce the ,english pint to the ,paris1 divide by ,no4 ,,vi4 ,,table of the ,weights of the different ,gasses1 at #bh ,french inches1 or #bi4hd ,english inches barometrical pressure1 and at #aj 7#ed4e7 of temperature1 expressed in ,english measure and ,english ,troy weight4 ,names of the ,gasses4 ,weight of a ,weight of a cubical inch4 cubical foot4 7,a7 qrs4 oz4 dr4 qrs4 ,atmospheric air 4#cbaab #a #a #ae ,azotic gas 4#cjjfd #a #j #ci4e ,oxygen gas 4#cdbaa #a #a #ea ,hydrogen gas 4#jbcid #j #j #da4bf ,carbonic acid gas 4#ddajh #a #d #da 7,b7 ,nitrous gas 4#cgjjj #a #b #ci ,ammoniacal gas 4#aheae #j #e #ai4gc ,sulphurous acid gas 4#gaehj #b #d #ch ,note ,a3 ,these five were ascertained by ,mr ,lavoisier himself4--,e4 ,note ,b3 ,the last three are inserted by ,mr ,lavoisier upon the authority of ,mr ,kirwan4--,e4 ,no4 ,,vii4 ,tables of the ,specific ,gravities of different bodies4 #a4 ,metallic ,substances4 ,,gold4 ,pure gold of #bd carats melted but not hammered #ai4beha ,the same hammered #ai4cfag ,gold of the ,parisian standard1 #bb carats fine1 not hammered7,a7 #ag4dhfc ,the same hammered #ag4ehid ,gold of the standard of ,french coin1 #ba-bb_/cb carats fine1 not hammered #ag4djbb ,the same coined #ag4fdgd ,gold of the ,french trinket standard1 #bj carats fine1 not hammered #ae4gjij ,the same hammered #ae4ggdf ,note ,a3 ,the same with ,sterling4 ,,silver4 ,pure or virgin silver1 #bd deniers1 not hammered #aj4dgdc ,the same hammered #aj4eajg ,silver of the ,paris standard1 #aa deniers #aj grains fine1 not hammered7,b7 #aj4ageb ,the same hammered #aj4cgfe ,silver1 standard of ,french coin1 #aj deniers #ba grains fine1 not hammered #aj4jdgf ,the same coined #aj4djgg ,note ,b3 ,this is #aj grs4 finer than ,sterling4 ,,platina4 ,crude platina in grains #ae4fjag ,the same1 after being treated with muriatic acid #af4geba ,purified platina1 not hammered #ai4ejjj ,the same hammered #bj4ccff ,the same drawn into wire #ba4jdag ,the same passed through rollers #bb4jfij ,,copper ,,and ,,brass4 ,copper1 not hammered #g4ghhj ,the same wire drawn #h4hghe ,brass1 not hammered #h4cieh ,the same wire drawn #h4edda ,,iron ,,and ,,steel4 ,cast iron #g4bjgj ,bar iron1 either screwed or not #g4ghhj ,steel neither tempered nor screwed #g4hcca ,steel screwed but not tempered #g4hdjd ,steel tempered and screwed #g4hahj ,steel tempered and not screwed #g4hafc ,,tin4 ,pure tin from ,cornwall melted and not screwed #g4biad ,the same screwed #g4biid ,malacca tin1 not screwed #g4bifc ,the same screwed #g4cjfe ,molten lead #aa4cebc ,molten zinc #g4aijh ,molten bismuth #i4hbbg ,molten cobalt #g4haai ,molten arsenic #e4gfcc ,molten nickel #g4hjgj ,molten antimony #f4gjba ,crude antimony #d4jfdc ,glass of antimony #d4idfd ,molybdena #d4gche ,tungstein #f4jffe ,mercury #ac4efha #b4 ,precious ,stones4 ,white ,oriental diamond #c4ebab ,rose-coloured ,oriental ditto #c4ecaj ,oriental ruby #d4bhcc ,spinell ditto #c4gfjj ,ballas ditto #c4fdeh ,brasillian ditto #c4ecaa ,oriental topas #d4jajf ,ditto ,pistachio ditto #d4jfae ,brasillian ditto #c4ecfe ,saxon topas #c4efdj ,ditto white ditto #c4eece ,oriental saphir #c4iida ,ditto white ditto #c4iiaa ,saphir of ,puy #d4jgfi ,ditto of ,brasil #c4acjg ,girasol #d4jjjj ,ceylon jargon #d4dafa ,hyacinth #c4fhgc ,vermillion #d4bbii ,bohemian garnet #d4ahhh ,dodecahedral ditto #d4jfbg ,syrian ditto #d4jjjj ,volcanic ditto1 with #bd sides #b4dfhd ,peruvian emerald #b4ggee ,crysolite of the jewellers #b4ghba ,ditto of ,brasil #b4fibc ,beryl1 or ,oriental aqua marine #c4edhi ,occidental aqua marine #b4gbbg #c4 ,silicious ,stones4 ,pure rock cristal of ,madagascar #b4fecj ,ditto of ,brasil #b4febf ,ditto of ,europe1 or gelatinous #b4fedh ,cristallized quartz #b4fedf ,amorphous ditto #b4fdga ,oriental agate #b4eija ,agate onyx #b4fcge ,transparent calcedony #b4ffdj ,carnelian #b4facg ,sardonyx #b4fjbe ,prase #b4ehje ,onyx pebble #b4ffdd ,pebble of ,rennes #b4fech ,white jade #b4iejb ,green jade #b4iffj ,red jasper #b4ffab ,brown ditto #b4fiaa ,yellow ditto #b4gaja ,violet ditto #b4gaaa ,gray ditto #b4gfdj ,jasponyx #b4hafj ,black prismatic hexahedral schorl #c4cheb ,black spary ditto #c4cheb ,black amorphous schorl1 called antique basaltes #b4ibbe ,paving stone #b4daeh ,grind stone #b4adbi ,cutler's stone #b4aaac ,fountainbleau stone #b4efaf ,scyth stone of ,auvergne #b4efch ,ditto of ,lorrain #b4ebih ,mill stone #b4dhce ,white flint #b4eida ,blackish ditto #b4ehag #d4 ,various ,stones1 c4 ,opake green ,italian serpentine1 or gabro of the ,florentines #b4dbie ,coarse ,briancon chalk #b4gbgd ,spanish chalk #b4gijb ,foliated lapis ollaris of ,dauphiny #b4gfhg ,ditto ditto from ,sweden #b4heca ,muscovy talc #b4giag ,black mica #b4ijjd ,common schistus or slate #b4fgah ,new slate #b4hece ,white rasor hone #b4hgfc ,black and white hone #c4acaa ,rhombic or ,iceland cristal #b4gaea ,pyramidal calcareous spar #b4gada ,oriental or white antique alabaster #b4gcjb ,green ,campan marble #b4gdag ,red ,campan marble #b4gbdb ,white ,carara marble #b4gafh ,white ,parian marble #b4hcgf ,various kinds of calcareous stones from #a4chfd used in ,france for building4 to #b4cijb ,heavy spar #d4dcjj ,white fluor #c4aeee ,red ditto #c4aiaa ,green ditto #c4ahag ,blue ditto #c4afhh ,violet ditto #c4ageg ,red scintilant zeolite from ,edelfors #b4dhfh ,white scintilant zeolite #b4jgci ,cristallized zeolite #b4jhcc ,black pitch stone #b4jdii ,yellow pitch stone #b4jhfj ,red ditto #b4ffie ,blackish ditto #b4caia ,red porphyry #b4gfea ,ditto of ,dauphiny #b4gjcc ,green serpentine #b4hifj ,black ditto of ,dauphiny1 called variolite #b4icci ,green ditto from ,dauphiny #b4ihhc ,ophites #b4igbb ,granitello #c4jfbf ,red ,egyptian granite #b4feda ,beautiful red granite #b4gfji ,granite of ,girardmas #b4gafc ,pumice stone 4#iade ,lapis obsidianus #b4cdhj ,pierre de ,volvic #b4cbje ,touch stone #b4daec ,basaltes from ,giants ,causeway #b4hfdb ,ditto prismatic from ,auvergne #b4daec ,glass gall #b4hedh ,bottle glass #b4gcbe ,green glass #b4fdbc ,white glass #b4hibb ,st ,gobin cristal #b4dhhb ,flint glass #c4cbic ,borax glass #b4fjgj ,seves porcelain #b4adeg ,limoges ditto #b4cdaj ,china ditto #b4chdg ,native sulphur #b4jccb ,melted sulphur #a4iijg ,hard peat #a4cbij ,ambergrease 4#ibfc ,yellow transparent amber #a4jghj #e4 ,liquids4 ,distilled water #a4jjjj ,rain water #a4jjjj ,filtered water of the ,seine #a4jjjae ,arcueil water #a4jjjdf ,avray water #a4jjjdc ,sea water #a4jbfc ,water of the ,dead ,sea #a4bdjc ,burgundy wine 4#iiae ,bourdeaux ditto 4#iici ,malmsey ,madeira #a4jchb ,red beer #a4jcch ,white ditto #a4jbca ,cyder #a4jaha ,highly rectified alkohol 4#hbic ,common spirits of wine 4#hcga ,alkohol #ae pts4 water #a part4 4#hebg #ad #b 4#hfgd #ac #c 4#hhae #ab #d 4#hidg #aa #e 4#ijge #aj #f 4#iaii #i #g 4#icag #h #h 4#idbg #g #i 4#ieai #f #aj 4#ieid #e #aa 4#ifgd #d #ab 4#igcc #c #ac 4#igia #b #ad 4#iheb #a #ae 4#iiai ,sulphuric ether 4#gcid ,nitric ether 4#ijhh ,muriatic ether 4#gbih ,acetic ether 4#hffd ,sulphuric acid #a4hdji ,nitric ditto #a4bgae ,muriatic ditto #a4aidj ,red acetous ditto #a4jbea ,white acetous ditto #a4jace ,distilled ditto ditto #a4jjie ,acetic ditto #a4jfbf ,formic ditto 4#iidb ,solution of caustic ammoniac1 or volatil alkali fluor 4#higj ,essential or volatile oil of turpentine 4#hfig ,liquid turpentine 4#iiaj ,volatile oil of lavender 4#hich ,volatile oil of cloves #a4jcfc ,volatile oil of cinnamon #a4jdci ,oil of olives 4#iaec ,oil of sweet almonds 4#iagj ,lintseed oil 4#idjc ,oil of poppy seed 4#ibhh ,oil of beech mast 4#iagf ,whale oil 4#ibcc ,womans milk #a4jbjc ,mares milk #a4jcdf ,ass milk #a4jcee ,goats milk #a4jcda ,ewe milk #a4jdji ,cows milk #a4jcbd ,cow whey #a4jaic ,human urine #a4jajf #f4 ,resins and ,gums ,common yellow or white rosin #a4jgbg ,arcanson #a4jheg ,galipot7,a7 #a4jhai ,baras7,a7 #a4jdda ,sandarac #a4jibj ,mastic #a4jgdb ,storax #a4ajih ,opake copal #a4acih ,transparent ditto #a4jdeb ,madagascar ditto #a4jfjj ,chinese ditto #a4jfbh ,elemi #a4jahb ,oriental anime #a4jbhd ,occidental ditto #a4jdbf ,labdanum #a4ahfb ,ditto in tortis #b4dicc ,resin of guaiac #a4bbhi ,ditto of jallap #a4bahe ,dragons blood #a4bjde ,gum lac #a4acij ,tacamahaca #a4jdfc ,benzoin #a4jibd ,alouchi7,b7 #a4jfjd ,caragna7,c7 #a4abdd ,elastic gum 4#icce ,camphor 4#ihhg ,gum ammoniac #a4bjga ,sagapenum #a4bjjh ,ivy gum7,d7 #a4bidh ,gamboge #a4bbaf ,euphorbium #a4abdd ,olibanum #a4agcb ,myrrh #a4cfjj ,bdellium #a4cgag ,aleppo ,scamony #a4bced ,smyrna ditto #a4bgdc ,galbanum #a4babj ,assafoetida #a4cbge ,sarcocolla #a4bfhd ,opoponax #a4fbbf ,cherry tree gum #a4dhag ,gum ,arabic #a4debc ,tragacanth #a4cafa ,basora gum #a4dcdf ,acajou gum7,e7 #a4ddef ,monbain gum7,f7 #a4dbjf ,inspissated juice of liquorice #a4gbbh ---- ,acacia #a4eaec ---- ,areca #a4degc ,terra ,japonica #a4cihj ,hepatic aloes #a4cehf ,socotrine aloes #a4cgie ,inspissated juice of ,st ,john's wort #a4ebfc ,opium #a4ccff ,indigo 4#gfij ,arnotto 4#eief ,yellow wax 4#ifdh ,white ditto 4#ifhf ,ouarouchi ditto7,g7 4#higj ,cacao butter 4#hiaf ,spermaceti 4#idcc ,beef fat 4#ibcb ,veal fat 4#icdb ,mutton fat 4#ibce ,tallow 4#idai ,hoggs fat 4#icfh ,lard 4#idgh ,butter 4#idbc ,note ,a3 ,resinous juices extracted in ,france from the ,pine4 ,vide ,bomare's ,dict4 ,note ,b3 ,odoriferous gum from the tree which produces the ,cortex ,winteranus4 ,bomare4 ,note ,c3 ,resin of the tree called in ,mexico ,caragna1 or ,tree of ,madness4 ,ibid4 ,note ,d3 ,extracted in ,persia and the warm countries from ,hedera terrestris4--,bomare4 ,note ,e3 ,from a ,brasilian tree of this name4--,ibid4 ,note ,f3 ,from a tree of this name4--,ibid4 ,note ,g3 ,the produce of the ,tallow ,tree of ,guayana4 ,vide ,bomare's ,dict4 #g4 ,woods4 ,heart of oak #fj years old #a4agjj ,cork 4#bdjj ,elm trunk 4#fgaj ,ash ditto 4#hdej ,beech 4#hebj ,alder 4#hjjj ,maple 4#geej ,walnut 4#fgaj ,willow 4#ehej ,linden 4#fjdj ,male fir 4#eejj ,female ditto 4#dihj ,poplar 4#chcj ,white ,spanish ditto 4#ebid ,apple tree 4#gicj ,pear tree 4#ffaj ,quince tree 4#gjej ,medlar 4#iddj ,plumb tree 4#ghej ,olive wood 4#ibgj ,cherry tree 4#gaej ,filbert tree 4#fjjj ,french box 4#iabj ,dutch ditto #a4cbhj ,dutch yew 4#ghhj ,spanish ditto 4#hjgj ,spanish cypress 4#fddj ,american cedar 4#efjh ,pomgranate tree #a4cedj ,spanish mulberry tree 4#higj ,lignum vitae #a4cccj ,orange tree 4#gjej ,note--,the numbers in the above ,table1 if the ,decimal point be carried three figures farther to the right hand1 nearly express the absolute weight of an ,english cube foot of each substance in averdupois ounces4 ,see ,no4 ,,viii4 of the ,appendix4--,e4 ,no4 ,,viii4 ,,additional4 ,,rules for ,calculating the ,absolute ,gravity in ,english ,troy ,weight of a ,cubic ,foot and ,inch1 ,english ,measure1 of any ,substance whose ,specific ,gravity is known#fd4 ,in #afif1 ,mr ,everard1 balance-maker to the ,exchequer1 weighed before the ,commissioners of the ,house of ,commons #bade4f cubical inches1 by the ,exchequer standard foot1 of distilled water1 at the temperature of #ee of ,fahrenheit1 and found it to weigh #aaca oz4 #ad dts4 ,troy1 of the ,exchequer standard4 ,the beam turned with #f grs4 when loaded with #cj pounds in each scale4 ,hence1 supposing the pound averdupois to weigh #gjjj grs4 ,troy1 a cubic foot of water weighs #fb-a_/b pounds averdupois1 or #ajjj ounces averdupois1 wanting #ajf grains ,troy4 ,and hence1 if the specific gravity of water be called #ajjj1 the proportional specific gravities of all other bodies will nearly express the number of averdupois ounces in a cubic foot4 ,or more accurately1 supposing the specific gravity of water expressed by #a4 and of all other bodies in proportional numbers1 as the cubic foot of water weighs1 at the above temperature1 exactly #dcgdhi4d grains ,troy1 and the cubic inch of water #bec4age grains1 the absolute weight of a cubical foot or inch of any body in ,troy grains may be found by multiplying their specific gravity by either of the above numbers respectively4 ,by ,everard's experiment1 and the proportions of the ,english and ,french foot1 as established by the ,royal ,society and ,french ,academy of ,sciences1 the following numbers are ascertained4 ,paris grains in a ,paris cube foot of water #fdeeaa ,english grains in a ,paris cube foot of water #ebiibb ,paris grains in an ,english cube foot of water #eccbdg ,english grains in an ,english cube foot of water #dcgdhi4d ,english grains in an ,english cube inch of water #bec4age ,by an experiment of ,picard with the measure and weight of the ,chatelet1 the ,paris cube foot of water contains of ,paris grains #fdacbf ,by one of ,du ,hamel1 made with great care #fdacgf ,by ,homberg #fdafff ,these show some uncertainty in measures or in weights2 but the above computation from ,everard's experiment may be relied on1 because the comparison of the foot of ,england with that of ,france was made by the joint labours of the ,royal ,society of ,london and the ,french ,academy of ,sciences3 ,it agrees likewise very nearly with the weight assigned by ,mr ,lavoisier1 #gj ,paris pounds to the cubical foot of water4 ,no4 ,,ix4 ,,tables for ,converting ,ounces1 ,drams1 and ,grains1 ,troy1 into ,decimals of the ,troy ,pound of #ab ,ounces1 and for ,converting ,decimals of the ,pound ,troy into ,ounces1 c4 ,i4 ,for ,grains4 ,grains ,pound4 #a 4#jjjagcf #b 4#jjjcdgb #c 4#jjjebjh #d 4#jjjfidd #e 4#jjjhfha #f 4#jjajdag #g 4#jjabaec #h 4#jjachhi #i 4#jjaefbe #aj 4#jjagcfa #bj 4#jjcdgbb #cj 4#jjebjhc #dj 4#jjfiddd #ej 4#jjhfhjf #fj 4#jajdafg #gj 4#jabaebh #hj 4#jachhhi #ij 4#jaefbej #ajj 4#jagcfaa #bjj 4#jcgdbbb #cjj 4#jebjhcc #djj 4#jfidddd #ejj 4#jhfhjee #fjj 4#ajdafff #gjj 4#abaebgg #hjj 4#achhhhh #ijj 4#aefbdii #ajjj 4#agcfaaj #bjjj 4#cdgbbbj #cjjj 4#ebjhccj #djjj 4#fiddddj #ejjj 4#hfhjeej #fjjj #a4jdahffj #gjjj #a4baebggj #hjjj #a4chhhhhj #ijjj #a4efbdiij ,,ii4 ,for ,drams4 ,drams ,pound4 #a 4#jajdafg #b 4#jbjhccc #c 4#jcabejj #d 4#jdafffg #e 4#jebjhcc #f 4#jfbejjj #g 4#jgbiafg #h 4#jhccccc ,,iii4 ,for ,ounces4 ,ounces ,pounds4 #a 4#jhccccc #b 4#afffffg #c 4#bejjjjj #d 4#ccccccc #e 4#daffffg #f 4#ejjjjjj #g 4#ehccccc #h 4#ffffffg #i 4#gejjjjj #aj 4#hcccccc #aa 4#iaffffg #ab #a4jjjjjjj ,,iv4 ,decimals of the ,pound into ,ounces1 c4 ,tenth parts4 lib4 oz4 dr4 gr4 #j4a #a #a #cf #j4b #b #c #ab #j4c #c #d #dh #j4d #d #f #bd #j4e #f #j #j #j4f #g #a #cf #j4g #h #c #ab #j4h #i #d #dh #j4i #aj #f #bd ,hundredth parts4 #j4ja #j #j #eg4f #j4jb #j #a #ee4b #j4jc #j #b #eb4h #j4jd #j #c #ej4d #j4je #j #d #dh4j #j4jf #j #e #de4f #j4jg #j #f #dc4b #j4jh #j #g #dj4h #j4ji #j #c #ch4d ,thousandths4 #j4jja #j #j #e4gf #j4jjb #j #j #aa4eb #j4jjc #j #j #ag4bh #j4jjd #j #j #bc4jd #j4jje #j #j #bh4hj lib4 grs4 #j4jjf #cd4ef #j4jjg #dj4cb #j4jjh #df4jh #j4jji #ea4hd ,ten thousandth parts4 #j4jjja #j4egf #j4jjjb #a4aeb #j4jjjc #a4gbh #j4jjjd #b4cjd #j4jjje #b4hhj #j4jjjf #c4def #j4jjjg #d4jcb #j4jjjh #d4fjh #j4jjji #e4ahd ,hundred thousandth parts4 #j4jjjja #j4jeb #j4jjjjb #j4aae #j4jjjjc #j4agc #j4jjjjd #j4bcj #j4jjjje #j4bhh #j4jjjjf #j4cdf #j4jjjjg #j4djc #j4jjjjh #j4dfa #j4jjjji #j4eah ,no4 ,x4 ,,table of the ,english ,cubical ,inches and ,decimals corresponding to a determinate ,troy ,weight of ,distilled ,water at the ,temperature of #ee1 calculated from ,everard's experiment4 ,for ,grains4 ,grs4 ,cubical inches4 #a 4#jjci #b 4#jjgh #c 4#jaah #d 4#jaeg #e 4#jaig #f 4#jbcf #g 4#jbge #h 4#jcae #i 4#jced #aj 4#jcid #bj 4#jghh #cj 4#aahb #dj 4#aegg #ej 4#aiga ,for ,drams4 ,drams4 ,cubical inches4 #a 4#bcfe #b 4#dgca #c 4#gjid #d 4#idfc #e #a4ahbi #f #a4daie #g #a4fefa ,for ,ounces4 ,oz4 ,cubical inches4 #a #a4hibg #b #c4ghee #c #e4fghb #d #g4egaj #e #i4dfca #f #aa4cefe #g #ac4bdic #h #ae4adbj #i #ag4jgdh #aj #ah4ibgf #aa #bj4hbjd ,for ,pounds4 ,libs4 ,cubical inches4 #a #bb4gaca #b #de4dbfc #c #fh4acid #d #ij4hebe #e #aac4efeg #f #acf4bghh #g #aeh4iiai #h #aha4gjea #i #bjd4dahc #aj #bbg4acad #ej #aace4fegd #ajj #bbga4cadh #ajjj #bbgac4adhh ,,footnotes3 #fb ,for the materials of this ,article the ,translator is indebted to ,professor ,robertson4 #fc ,it is said1 ,belidor ,archit4 ,hydrog4 to contain #ca oz4 #fd grs4 of water1 which makes it #eh4jge ,english inches2 but1 as there is considerable uncertainty in the determinations of the weight of the ,french cubical measure of water1 owing to the uncertainty of the standards made use of1 it is better to abide by ,mr ,everard's measure1 which was with the ,exchequer standards1 and by the proportions of the ,english and ,french foot1 as established by the ,french ,academy and ,royal ,society4 #fd ,the whole of this and the following article was communicated to the ,translator by ,professor ,robinson4--,e4 ,,the ,,plates ,illustration3 ,plate ,i ,illustration3 ,plate ,i 7continued7 ,illustration3 ,plate ,,ii ,illustration3 ,plate ,,ii 7continued7 ,illustration3 ,plate ,,iii ,illustration3 ,plate ,,iii 7continued7 ,illustration3 ,plate ,,iv ,illustration3 ,plate ,,iv 7continued7 ,illustration3 ,plate ,v ,illustration3 ,plate ,v 7continued7 ,illustration3 ,plate ,,vi ,illustration3 ,plate ,,vi 7continued7 ,illustration3 ,plate ,,vii ,illustration3 ,plate ,,vii 7continued7 ,illustration3 ,plate ,,viii ,illustration3 ,plate ,,viii 7continued7 ,illustration3 ,plate ,,ix ,illustration3 ,plate ,,ix 7continued7 ,illustration3 ,plate ,x ,illustration3 ,plate ,x 7continued7 ,illustration3 ,plate ,,xi ,illustration3 ,plate ,,xi 7continued7 ,illustration3 ,plate ,,xii ,illustration3 ,plate ,,xii 7continued7 ,illustration3 ,plate ,,xii 7continued7 ,illustration3 ,plate ,,xii 7continued7 ,illustration3 ,plate ,,xii 7continued7 ,illustration3 ,plate ,,xiii ,illustration3 ,plate ,,xiii 7continued7 ,,the ,,end4