,illustration ,,scientific ,,american ,,supplement ,,no4 #bhh ,,new ,,york1 ,,july #i1 #ahha ,scientific ,american ,supplement4 ,vol4 ,,xi1 ,no4 #bhh4 ,scientific ,american established #ahde ,scientific ,american ,supplement1 #e a year4 ,scientific ,american and ,supplement1 #g a year4 99 99 99 99 99 ,,table ,,of ,,contents4 ,i4 ,,engineering ,,and ,,mechanics--,dry ,air ,refrigerating ,machine4 #e figures4 ,plan1 elevation1 and diagrams of a new ,english dry air refrigerator ,thomas' ,improved ,steam ,wheel4 #a figure ,the ,american ,society of ,civil ,engineers4 ,address of ,president ,francis1 at the ,thirteenth ,annual ,convention1 at ,montreal4 ,the ,water ,power of the ,united ,states1 and its ,utilization ,,ii4 ,,technology ,,and ,,chemistry4--,alcohol in ,nature4 ,its presence in earth1 atmosphere1 and water4 #f figures4 ,distillatory apparatus and 7magnified7 iodoform crystals from snow water1 from rain water1 from vegetable mould1 etc4 ,detection of ,alcohol in ,transparent ,soaps4 ,by ,h4 ,,jay ,on the ,calorific ,power of ,fuel1 and on ,thompson's ,calorimeter4 ,by ,j4,w4 ,,thomas ,explosion as an ,unknown ,fire ,hazard4 ,a suggestive review of the conditions of explosions1 with curious examples ,carbon4 ,symbol ,c4 ,combining weight4 #ab4 ,by ,t4 ,a4 ,,pooley ,second article on elementary chemistry written for brewers ,manufacture of ,soaps and their ,production4 ,by ,w4 ,j4 ,,menzies ,the ,preparation of ,perfume ,pomades4 #a figure4 ,ensoufflage apparatus for perfumes ,organic ,matter in ,sea ,water ,bacteria ,life4 ,influence of heat and various gases and chemical compounds on bacteria life ,on the ,composition of ,elephant's ,milk4 ,by ,dr4 ,,chas4 ,a4 ,,doremus4 ,comparison of elephant's milk with that of ten other mammals ,the ,chemical ,composition of ,rice4 ,maize1 and ,barley4 ,by ,j4 ,,steiner ,petroleum ,oils4 ,character and properties of the various distillates of crude petroleum4 ,fire risks attending the use of the lighter petroleum oils ,composition of the ,petroleum of the ,caucasus4 ,by ,p4 ,,schulzenberger and ,n4 ,,tonine ,notes on ,cananga ,oil4 or ,ilang-,ilang ,oil4 ,by ,f4 ,a4 ,,fl,,ckiger4 #a figure4 ,flower and leaf of ,cananga odorata ,chian ,turpentine1 and the ,tree which ,produces ,it4 ,by ,dr4 ,,stiepowich4 of ,chios1 ,turkey ,on the ,change of ,volume which ,accompanies the ,galvanic ,deposition of a ,metal4 ,by ,m4 ,e4 ,,bouty ,analysis of the ,rice ,soils of ,burmah4 ,by ,r4 ,,romanic1 ,chemical ,examiner1 ,british ,burmah ,,iii4 ,,physics ,,and ,,physical ,,apparatus4--,seyfferth's ,pyrometer4 #g figures4--,pyrometer with electric indicator4--,method of mounting by means of a cone on vacuum apparatus4--,mounting by means of a sleeve4--,mounting by means of a thread on a tube4-- ,mounting by means of a clasp in reservoirs4--,the pyrometer mounted on a bone-black furnace4--,mounted on a brick furnace ,delicate ,scientific ,instruments4 ,by ,,edgar ,l4 ,,larkin4 ,an interesting description of the more powerful and delicate instruments of research used by modern scientists and their marvelous results ,the ,future ,development of ,electrical ,appliances4 ,lecture by ,prof4 ,j4 ,w4 ,,perry before the ,london ,society of ,arts4--,methods and units of electrical measurements ,researches on the ,radiant ,matter of ,crookes and the ,mechanical ,theory of ,electricity4 ,by ,dr4 ,w4 ,f4 ,,gintl ,economy of the ,electric ,light4 ,w4 ,h4 ,,preece',s ,experiments ,investigations ,on the ,space ,protected by a ,lightning ,conductor4 ,by ,,wm4 ,h4 ,,preece4--#e figures ,photo-,electricity of ,fluor ,spar ,crystals ,the ,aurora ,borealis and ,telegraph ,cables ,the ,photographic ,image3 ,what ,it ,is4 ,by ,t4 ,h4 ,,morton4 #a figure4--,section of sensitive plate after exposure and during development ,gelatine ,transparencies for the ,lantern ,an ,integrating ,machine4 ,by ,c4 ,v4 ,,boys4--#a figure ,upon a ,modification of ,wheatstone's ,microphone and its ,applicability to ,radiophonic ,researches4 ,by ,,alex4 ,,graham ,,bell1--#b figures ,,iv4 ,,architecture4--,suggestions in ,architecture1 #a figure4--,a pair of ,english cottages4 ,by ,a4 ,,cawston 99 99 99 99 99 ,,alcohol ,,in ,,nature--,,its ,,presence ,,in ,,the ,,earth1 ,,water1 ,,and ,,atmosphere4 ,a ,chemist of merit1 ,mr4 ,a4 ,mntz1 who has already made himself known by important labors and by analytical researches of great precision1 has been led to a very curious and totally unexpected discovery1 on the subject of which he has kindly given us information in detail1 which we place before our readers4#a ,mr4 ,mntz has discovered that arable soil1 waters of the ocean and streams1 and the atmosphere contain traces of alcohol2 and that this compound1 formed by the fermentation of organic matters1 is everywhere distributed throughout nature4 ,we should add that only infinitesimal quantities are involved--reaching only the proportion of millionths--yet the fact1 for all that1 offers a no less powerful interest4 ,the method of analysis which has permitted the facts to be shown is very elegant and scrupulously exact1 and is worthy of being made known4 ,footnote #a3 ,the accompanying engravings have been made from drawings of the apparatus in the laboratory of which ,mr4 ,mntz is director1 at the ,agronomic ,institute4 ,illustration3 ,,fig4 #a4--;,,first ,,distillatory ,,apparatus4 ,illustration3 ,,fig4 #b4--,,second ,,distillatory ,,apparatus4 ,mr4 ,mntz's method of procedure is as follows3 ,he submits to distillation three or four gallons of snow1 rain1 or sea water in an apparatus such as shown in ,fig4 #a4 ,the part which serves as a boiler1 and which holds the liquid to be distilled1 is a milk-can1 ,b4 ,the vapors given off through the action of the heat circulate through a leaden tube some thirty-three feet in length1 and then traverse a tube inclosed within a refrigerating cylinder1 ,t1 which is kept constantly cold by a current of water4 ,they are finally condensed in a glass flask1 ,r1 which forms the receiver4 ,when #ajj or #aej cubic centimeters of condensed liquid 7which contains all the alcohol7 are collected in the receiver1 the operations are suspended4 ,the liquid thus obtained is distilled anew in a second apparatus1 which is analogous to the preceding but much smaller 7,fig4 #b74 ,the liquid is heated in the flask1 ,b1 and its vapor1 after traversing a glass worm1 is condensed in the tube1 ,t4 ,the operation is suspended as soon as five or six cubic centimeters of the condensed liquid have been collected in the test-tube1 ,r4 ,the latter is now removed1 and to its liquid contents1 there is added a small quantity of iodine and carbonate of soda4 ,the mixture is slightly heated1 and soon there are seen forming1 through precipitation1 small crystals of iodoform4 ,under such circumstances1 iodoform could only have been formed through the presence of an alcohol in the liquid4 ,these analytical operations are verified by ,mr4 ,mntz as follows3 ,he distills in the same apparatus three to four gallons of chemically pure distilled water1 and ascertains positively that under these conditions iodine and carbonate of soda give absolutely no reaction4 ,finally1 to complete the demonstration and to ascertain the approximate quantity of alcohol contained in natural waters1 he undertakes the double fractional distillation of a certain quantity of pure water to which he has previously added a one-millionth part of alcohol4 ,under these circumstances the iodine and carbonate of soda give a precipitate of iodoform exactly similar to that obtained by treating natural waters4 ,illustration3 ,fig4 #c4--;,,iodoform ,,crystals ,,obtained ,,directly 7greatly magnified74 ,illustration3 ,,fig4 #d1--;,,iodoform ,,crystals ,,obtained ,,with ,,rain ,,water4 ,in the case of arable soil1 ,mr4 ,mntz stirs up a weighed quantity of the material to be analyzed in a certain proportion of water1 distills it in the smaller of the two apparatus1 and detects the alcohol by means of the same operation as before4 ,illustration3 ,,fig4 #e4--;,,iodoform ,,crystals ,,obtained ,,with ,,snow ,,water4 ,the formation of iodoform by precipitation under the action of iodine and carbonate of soda is a very sensitive test for alcohol4 ,iodoform has sharply defined characters which allow of its being very easily distinguished4 ,its crystalline form1 especially1 is entirely typical1 its color is pale yellowish1 and1 when it is examined under the microscope1 it is seen to be in the form of six-pointed stars precisely like the crystalline form of snow4 ,mr4 ,mntz has not been contented to merely submit the iodoform precipitates obtained by him to microscopical examination1 but has preserved the aspect of his preparations by means of micro-photography4 ,the figures annexed show some of the most characteristic of the proofs4 ,fig4 #a shows crystals of iodoform obtained with pure water to which one-millionth part of alcohol had been added4 ,fig4 #b exhibits the form of the crystals obtained with rain water2 and ,fig4 #c1 those with water4 ,fig4 #d shows crystals obtained with arable soil or garden mould4 ,the first of ,mr4 ,mntz's experiments were made about four years ago2 but since that time he has treated a great number of rain and snow waters collected both at ,paris and in the country4 ,at every distillation all the apparatus was cleansed by prolonged washing in a current of steam2 and1 in order to confirm each analysis1 a corresponding experiment was made like the one before mentioned4 ,more than eighty trials gave results which were exactly identical4 ,the quantity of alcohol contained in rain1 snow1 and sea waters may be estimated at from one to several millionths4 ,cold water and melted snow seem to contain larger proportions of it than tepid waters4 ,in the waters of the ,seine it is found in appreciable quantities1 and in sewage waters the proportions increase very perceptibly4 ,vegetable mould is quite rich in it2 indeed it is quite likely that alcohol in its natural state has its origin in the soil through the fermentation of the organic matters contained therein4 ,it is afterward disseminated throughout the atmosphere in the state of vapor and becomes combined with the aqueous vapors whenever they become condensed4 ,the results which we have just recorded are1 as far as known to us1 absolutely new2 they constitute a work which is entirely original1 which very happily goes to complete the history of the composition of the soil and atmosphere1 and which does great credit to its author4--,la ,nature4 ,illustration3 ,,fig4 #f4--;,,iodoform ,,crystals ,,obtained ,,with ,,vegetable ,,mould4 99 99 99 99 99 ,,detection ,,of ,,alcohol ,,in ,,transparent ,,soaps4 ,by ,h4 ,,jay4 ,it appears that every article manufactured with the aid of alcohol is required on its introduction into ,france to pay duty on the supposed quantity of this reagent which has been used in its preparation4 ,certain transparent soaps of ,german origin are now met with1 made1 as is alleged1 without alcohol1 and the author proposes the following process for verifying this statement by ascertaining--the presence or absence of alcohol in the manufactured article3 #ej grms4 of soap are cut into very small pieces and placed in a phial of #bjj c4c4 capacity2 #cj grms4 sulphuric acid are then added1 and the phial is stoppered and agitated till the soap is entirely dissolved4 ,the phial is then filled up with water1 and the fatty acids are allowed to collect and solidify4 ,the subnatant liquid is drawn off1 neutralized1 and distilled4 ,the first #be c4c4 are collected1 filtered1 and mixed1 according to the process of ,,mm4 ,riche and ,bardy for the detection of alcohol in commercial methylenes1 with c4c4 sulphuric acid at #ah ,b41 then with the same volume of permanganate 7#ae grms4 per liter71 and allowed to stand for one minute4 ,he then adds #h drops of sodium hyposulphite at #cc ,b41 and #a c4c4 of a solution of magenta1 #a decigrm4 per liter4 ,if any alcohol is present there appears within five minutes a distinct violet tinge4 ,the presence of essential oils gives rise to a partial reduction of the permanganate without affecting the conversion of alcohol into aldehyd4 99 99 99 99 99 ,,on ,,the ,,calorific ,,power ,,of ,,fuel1 ,,and ,,on ,,thompson',s ,,calorimeter4 ,by ,j4,w4 ,,thomas1 ,f4,c4,s41 ,f4,i4,c4 ,a simple experiment1 capable of yielding results which shall be at least comparative1 has long been sought after by large consumers of coal and artificial fuel abroad in order to ascertain the relative calorific power possessed by each description1 as it is well known that the proportion of mineral matter and the chemical composition of coal differ widely4 ,the determination of the ash in coal is not a highly scientific operation2 hence it is not surprising that foreign merchants should have become alive to the importance of estimating its quantity4 ,while1 however1 the nature and quantity of the ash can be determined without much difficulty1 the determination of the chemical composition of coal entails considerable labor and skill2 hence a method giving the calorific power of any fuel in an exact and reliable manner by a simple experiment is a great desideratum4 ,this will become more obvious when one takes into consideration the many qualities and variable characters of the coals yielded by the ,south ,wales and ,north of ,england coal fields4 ,bituminous coals--giving some #fe per cent1 of coke--are preferred for some manufacturing purposes and in some markets4 ,bituminous steam coals1 yielding #ge per cent1 of coke1 are highly prized in others4 ,semi-bituminous steam coals1 yielding #hj to #hc per cent1 of coke1 are most highly valued1 and find the readiest sale abroad2 and anthracite steam coal 7dry coals71 giving from #he to #hh per cent1 of coke 7using the term coke as equivalent to the non-volatile portion of the coal7 is also exported in considerable quantity4 ,now the estimation of the ash of any of these varieties of coal would afford no evidence as to the class to which that coal belongs1 and there is no simple test that will give the calorific power of a coal1 and at the same time indicate the degree of bituminous or anthracitic character which it possesses4 ,in order to obtain such information it is necessary that the percentage of coke be determined together with the sulphur1 ash1 and water1 and these form data which at once show the nature of a fuel and give some indication of its value4 ,to ascertain the quantity of the sulphur1 ash1 and water with accuracy involves more skill and aptitude than can be bestowed by the non-professional public2 the consequence is that experiments entailing less time and precision1 like those devised by ,berthier and ,thompson1 have been tried more or less extensively4 ,in ,france and ,italy1 ,berthier's method--slightly modified in some instances--has been long used4 ,it is as follows3 #gj grammes of oxide of lead 7litharge7 and #aj grammes of oxychloride of lead are employed to afford oxygen for the combustion of #a gramme of fuel in a crucible4 ,from the weight of the button of lead1 and taking #h1jhj units as the equivalent of carbon1 the total heat-units of the fuel is calculated4 ,this experiment is very imperfect and erroneous upon scientific grounds1 since the hydrogen of the fuel is scarcely taken into account at all4 ,in the first place1 hydrogen consumes only one quarter as much oxygen as carbon1 and1 furthermore1 two-ninths only of the heating power of hydrogen is used as the multiplying number1 viz41 #h1jhj1 while the value of hydrogen is #cd1dfb4 ,in other words1 one-eighteenth only of the available hydrogen present in the fuel is shown in the result obtained4 ,apart from this my experience of the working of ,berthier's method has been by no means satisfactory4 ,there is considerable difficulty in obtaining pure litharge1 and it is almost impossible to procure a crucible which does not exert a reducing action upon the lead oxide4 ,some twelve months ago ,i went out to ,italy to test a large number of cargoes of coal with ,thompson's calorimeter1 and since then this apparatus has superseded ,berthier's process1 and is likely to come into more general use4 ,like ,berthier's method1 ,thompson's apparatus is not without its disadvantages1 and the purpose of this paper is to set these forth1 as well as to suggest a uniform method of working by means of which the great and irreconcilable differences in the results obtained by some chemists might be overcome4 ,it has already been observed that a coal rich in hydrogen shows a low heating power by ,berthier's method1 and it will become evident on further reflection that the higher the percentage of carbon the greater will be the indicated calorific power4 ,in fact a good sample of anthracite will give higher results than any other class of coal by ,berthier's process4 ,with ,thompson's calorimeter the reverse is the case1 as the whole of the heating power of the hydrogen is taken into account4 ,in short1 with careful working1 the more bituminous a coal is the more certain is it that its full heating power shall be exerted and recorded1 so far as the apparatus is capable of indicating it2 for when the result obtained is multiplied by the equivalent of the latent heat of steam the product is always below the theoretical heat units calculated from the chemical composition of the coal by the acid of ,favre and ,silbermann's figures for carbon and hydrogen4 ,on the other hand1 when the heating power of coal low in hydrogen is determined by ,thompson's calorimeter1 much difficulty is experienced in burning the carbon completely2 hence a low result is obtained4 ,from a large number of experiments ,i have found that when a coal does not yield more than #hf per cent1 of coke1 it gives its full comparative heating power1 but it is very questionable if equal results will be worked out if the coke exceeds the above amount although ,i have met with coals giving #hg per cent4 of coke which were perfectly manageable1 though in other cases the coal did not burn completely4 ,it will be noted that the non-volatile residue of anthracite is never as low as #hf per cent41 and this1 together with the very dry steam coals and bastard anthracite 7found over a not inextensive tract of the ,south ,wales ,coal field71 form a series of coals1 alike difficult to burn in ,thompson's calorimeter4 ,considerable experience has shown that in no single instance was the true comparative heating power of anthracite or bastard anthracite indicated4 ,with a view to accelerate the perfect combustion of these coals1 sugar1 starch1 bitumen1 and bituminous coals--substances rich in hydrogen--were employed1 mixed in varying proportions with the anthracitic coal1 but without the anticipated effect4 ,coke was also treated in a like manner4 ,without enlarging further upon these futile trials--all carefully and repeatedly verified--the results of my experiments and experience show that for coals of an anthracitic character1 yielding more than #hg per cent4 of coke1 or for coke itself1 ,thompson's calorimeter is not suited as an indicator of their comparative calorific power1 for the simple reason that some of the carbon is so graphitic in its nature that it will not burn perfectly when mixed with nitrate and chlorate of potash4 ,a sample of very pure anthracite used in the experiments referred to1 gave #ij4d per cent4 of non-volatile residue1 and only #j4hd per cent4 of ash4 ,this coal was not difficult to experiment with1 as combustion started with comparative ease and proceeded quite rapidly enough1 but in every instance a portion of the carbon was unconsumed1 and consequently instead of about #ac of rise in temperature only #aj were recorded4 ,since the calorific power of a coal is determined by the number of degrees ,fahrenheit which a given quantity of water is raised in temperature by a known weight of fuel1 it follows that every care should be taken that the experiment be performed under similar atmospheric conditions4 ,the oscillation of barometric pressure does not appear to affect the working1 but the temperature of the room in which the work was done1 and especially that of the water1 are most important considerations4 ,it has been observed by some who have used this apparatus--and ,i have frequently noticed it myself--that the lower the temperature of the water is under which the fuel is burnt the higher is the result found4 ,this has been explained on the assumption that the colder the water used1 the greater is the difference between the temperature of the room and that of the water2 hence it would be expedient that in all cases when such experiments are made the same difference of temperature between the air in the room and the water employed should always exist4 ,for example1 if the temperature of the room were #gj1 and the water at #fj1 then the same coal would give a like result with the water at #dj and the room at #ej4 ,this has been regarded as the more evident1 because the gases passing through the water escape under favorable conditions of working at the same temperature as the water1 and are perfectly deprived of any heat in excess of that possessed by the water4 ,under these circumstances it would seem only reasonable that this assumption should be correct4 ,it was1 however1 found after a large number of experiments upon the same sample of coal that this was not the case4 #cj grammes of coal which raises the temperature of the water #ac4d1 when the water at starting was #fj and the room at #gj1 gives #ac4g rise of temperature with the water at #dj and the room at #ej4 ,conversely1 when the water is at #gj and the room at #hj1 a lower result is obtained4 ,the explanation appears to be this3 ,the gas which escapes from the water was not in existence in the gaseous form previous to the experiment1 and the heat communicated to the gas being a definite quantity it follows that the more the gas is cooled the greater the proportion of chemical energy in the shape of heat will be utilized and recorded as calorific power4 ,in order1 therefore1 to make the experiment more simple and workable at all temperatures1 a sample of coal was selected1 which should be perfectly manageable and readily consumed4 ,appended is an analysis of the coal employed 7from ,ebbw ,vale1 ,monmouthshire73 ,composition per cent4 ,carbon4444444444444444444444444444444#h h4cc ,hydrogen44444444444444444444444444444 #e4jh ,oxygen4444444444444444444444444444444 #c4bh ,nitrogen44444444444444444444444444444 #j4ee ,sulphur444444444444444444444444444444 #j4gj ,ash4444444444444444444444444444444444 #a4bf ,water 7moisture7444444444444444444444 #j4hj ----- #ajj4jj ,in the following experiments the standard temperature of the water was taken as #fj ,f41 and as the coal gave #ac4d of rise of temperature1 #fg ,f4 was selected as the standard room temperature4 ,the reason for this room temperature is obvious1 for1 whatever heating effect the higher temperature of the room may have upon the water in the cylinder during the time occupied by the first half of the experiment1 would be compensated for by the loss sustained during the second half of the experiment1 when the temperature of the water exceeded that of the room4 ,the mean of numerous trials gave #ac4d ,f4 rise of temperature1 equal to #ad4gd lb4 of water per lb4 of coal4 ,when the water was at #ej and the room at #eg1 the mean of several experiments gave #ac4e rise of temperature4 ,when the water was #dj at starting and the room at #dg1 #ac4fe was the average rise of temperature4 ,trials were made at intermediate temperatures1 and the results always showed that higher figures were recorded when the water was coldest4 ,with a view of getting uniformity in the results it was thought well to make experiments1 in order to find out what temperature the room should be at1 so that this coal might give the same result with the water at #ej1 #dj1 or at intermediate temperatures4 ,without going much into detail1 it was found that when the temperature of the room was at #dj and that of the water #dj1 and the experiment was rapidly and carefully performed1 #ac4d rise of temperature was given2 but this result could be obtained without special effort when the room was #db and the water #dj at starting4 ,it is evident that the cooling effect of the air in the room upon the water cylinder is very appreciable when the water has reached #ac above that of the room4 ,when the water was at #ej and the room at #ee1 the coal gave #ac4d rise with ease and certainty1 and it would not be out of place to remark here that with those coals which burn well in ,thompson's calorimeter1 the results of several trials are remarkably uniform when properly performed4 ,with the water at #gj and the room at #hj1 a like result was worked out4 ,experiments at intermediate temperatures were also carried out 7see table in sequel74 ,it is true that the whole difference of temperature we are dealing with in making these corrections is only #j4be1 but #j4b in the result1 when multiplied by #ecg to bring it into calories1 as is done by the authorities in ,italy1 makes more than #ajj heat units--a serious difference when #e;d4 per ton fine is attached to every #ajj calories lower than the number guaranteed4 ,taking the latent heat of steam as #ecg ,c41 and multiplying this number by #ad4gd1 the evaporative power of the coal used in these experiments1 its equivalent in calories is #g1iae4 ,from the analysis of this coal1 disregarding the nitrogen and deducting an equivalent of hydrogen for the oxygen present1 the total heat units given by ,favre and ,silbermann's figures for carbon 7#h1jhj7 and hydrogen 7#cd1dfb7 will be #h1gdf4 ,it will be seen1 therefore1 that the calorific power1 as determined by ,thompson's apparatus1 gives a much lower result when multiplied by #ecg than the heat units calculated from the chemical composition of the coal4 ,when ,i used ,thompson's apparatus in the chemical laboratory at ,turin to determine the evaporative power of various cargoes of ,south ,wales coal1 it was agreed by mutual consent that the temperature of the water at starting should be #ci ,f4 7the temperature at which the heat unit was determined74 ,the temperature of the room was about #fj1 but this varied1 as the weather was somewhat severe and changeable4 ,under these conditions1 with the water at #ci and room #fj1 the coal which gives #ad4gd lb4 of water per lb4 of coal1 will give as high as #ae4hh lb4 of water per lb4 of coal4 ,this result multiplied by #ecgh1dif calories1 approaching much more nearly to the theoretic value4 ,this method of working is still practiced abroad1 but experience has shown that very widely differing results follow when working in this manner1 especially if the temperature of the room is changeable1 as it naturally is where ash determinations and other chemical work is proceeding simultaneously4 ,the time the experiment lasts1 taking the reading on a quickly rising thermometer and other considerations1 render the experiments anything but trustworthy when #j4b of a degree makes a difference of more than #ajj calories4 ,in the instructions supplied with ,thompson's calorimeter nothing is said as to the temperature of the room in which the experiment is performed1 but simply that the water shall be at #fj ,f4 ,if1 with the water at #fj1 a room were at #ej1 as it often is in winter1 a good coal would give #ad lb4 of water per lb4 of coal as the evaporative power2 but if in summer1 the room were at #ge and the water at #fj1 the same coal would give #ae lb4 of water per lb4 of coal4 ,if further evidence were needed of the effect of temperature consideration of the experiments already referred to will show how necessary it is that some general rule shall be adopted4 ,considerable stress is laid 7in the instructions7 upon the quantity of oxygen mixture used being determined by rough experiments4 ,this ,i have found leads to erroneous conclusions unless a number of experiments are tried in the calorimeter1 as it often happens that the quantity which appears to be best adapted is not that which yields a trustworthy result4 ,there are many samples of ,south ,wales coal1 #cj grains of which will require #aj parts of oxygen mixture in order to burn completely1 but since a little oxygen is lost in drying and grinding1 and few samples of chlorate are free from chloride1 it is not safe to use less than #aa parts of oxygen mixture1 but this amount is sufficient in all cases1 and never need be exceeded4 ,i have made numerous experiments with various coals 7anthracite1 steam1 semi-bituminous1 and bituminous1 including a specimen of the ten yard coal of ,derbyshire71 and find that with #aa parts of chlorate and nitrate of potash1 they are all perfectly manageable and yield the best results4 ,it is quite clear that the excess of chlorate is decomposed in all instances1 and the latent heat of the oxygen evolved1 but those coals which are best to experiment with did not yield results that differed when the quantity of oxygen mixture was reduced to nearly the limit required for combustion of the coal4 ,under these circumstances1 therefore1 the constant use of #aa parts of oxygen mixture--a suitable quantity for all coals exported--would enable operators to obtain similar figures1 and make the test uniform in different hands4 ,the following is a brief outline of the method of procedure recommended3 ,sample the coal until an average portion passes through a sieve having #fd meshes to the square inch4 ,take about #cjj grains 7#bj grammes7 of this and run through a brass wire gauze having #d1fjj meshes to the square inch1 taking care that the whole sample selected is thus treated4 ,one part of nitrate of potash and #c parts of chlorate of potash 7dry7 are separately ground in a mortar1 and repeatedly sifted through another wire gauze sieve1 having #a1jjj meshes to the square inch1 in order that the oxygen mixture shall not be ground to an impalpable powder1 as this is very undesirable4 ,it absorbs moisture rapidly1 and interferes with the regularity of the combustion when very fine4 #ccj grains of the powder are weighed out 7after drying71 and intimately incorporated with #cj grains of coal--better with a spatula than by rubbing in a mortar--and then introduced into a copper cylinder 7#c inches long by inch wide1 made from a copper tube71 and pressed down in small portions by a test-tube with such firmness as is required by the nature of the coal1 not tapped on the bottom1 since the rougher portions of the oxygen mixture rise to the surface4 ,as the temperature of a room is almost invariably much higher than the water supply1 a little hot water is added to that placed in the glass cylinder1 until the difference of temperature between the water and the room is about the mark indicated in the following table3 ,room at ,the water should be #hj ,f4 #gj ,f4 #gb #fd #fg #fj #fj #ed #ee #ej #ej #df #db #dj ,say1 for example1 the room was at #eg and the water placed in the cylinder was at #df3 add a little hot water and stir with the thermometer until it assumes #eb4 ,by the time the excess of water has been removed with a pipette until it is exactly level with the mark1 and all is ready1 the temperature will rise nearly #j4e4 ,let the thermometer be immersed in the water at least three minutes before reading4 ,the fuse should be placed in the mixture1 and everything at hand before reading and removing the thermometer4 ,after igniting the fuse and immersing the copper cylinder in the water1 the apparatus should be kept in the best position for the gases to be evolved all around the cylinder1 and the rate of combustion noted4 ,some coals are very unmanageable without practice1 and samples of patent fuel are sometimes met with1 containing unreasonable proportions of pitch1 which require some caution in working and very close packing1 inasmuch as small explosions occur during which a little of the fuel escapes combustion4 ,in order that the experiment shall succeed well1 experience has shown that the nature of the fuse employed has much to do with it4 ,plaited or woven wick is not adapted1 and will fail absolutely with dry coals1 unless it is made very free burning4 ,in this case not less than three-quarters of an inch in length is necessary1 and the weight of such is very appreciable4 ,i always use ,oxford cotton1 and thoroughly soak it in a moderately strong solution of nitrate of potash4 ,when dry it should burn a little too fast4 ,the cotton is rubbed between two pieces of cloth until it burns just freely enough2 then four cotton strands are taken1 twisted together1 and cut into lengths of inch and thoroughly dried4 ,open out the fuse at the lower end when placing it in the mixture so as to expose as much surface as possible in order to get a quick start1 but carefully avoid pressing the material1 and use a wire to fill up close to the fuse4 ,a slow start often spoils the experiment1 through the upper end of the cylinder becoming nearly filled up with potassic chloride1 etc4 ,by paying attention to such details1 and following the method recommended1 the apparatus yields very satisfactory results with bituminous and semi-bituminous coals4--,chemical ,news4 99 99 99 99 99 ,,explosion ,,as ,,an ,,unknown ,,fire ,,hazard4 ,words pass along with meanings which are simple conventionalities1 marking current opinions1 knowledge1 fancies1 and misjudgments4 ,they attain to new accretions of import as knowledge advances or opinions change1 and they are applied now to one set of ideas1 now to another4 ,hence there is nothing truer than the saying1 definitions are never complete4 ,the term explosion in its original introduction denoted the making of a noise2 it grew to comprehend the idea of force accompanied with violent outburst2 it is advancing to a stage in which it implies combustion as associated with destruction1 yet somewhat distinct from the abstract idea of the resolution of any form of matter into its elementary constituents4 ,the term1 however1 as yet takes in the idea of combustion as a decomposition in but a very limited degree1 and it may be said to be wavering at the line between expansion and dissociation4 ,strictly1 in insurance1 fire and explosion are different phenomena4 ,a policy insuring against fire-loss does not insure against loss by explosion4 ,it thereby enforces a distinction which exists1 or did exist1 in the popular mind2 and fire1 in an insurance sense1 as distinct from explosion1 was accurately defined by ,justice ,mc,ilvaine1 of the ,supreme ,court of ,ohio 7#ahgb71 in the case of the ,union ,insurance ,company vs4 ,forte1 i4e41 an explosion was a remote cause of loss and not the proximate cause1 when the fire was a burning of a gas jet which did not destroy1 though the explosion caused by the burning gas-jet did destroy4 ,earlier than this decision1 however 7in #aheb71 ,justice ,cushing1 of the ,supreme ,court of ,massachusetts1 in ,scripture vs4 ,lowell ,mutual ,fire ,insurance ,company1 somewhat anticipated later definition1 and pronounced for the liability of the underwriter where all damage by the explosion involves the ignition and burning of the agent of explosion4 ,that is1 for example1 the insurer is liable for damage caused by an explosion from gunpowder1 but not for an explosion from steam4 ,the ,massachusetts ,judge did not conceive any distinction as to fire-loss between the instantaneous burning of a barrel of gunpowder and the slower burning of a barrel of sulphur1 and insurance fire-loss is not to be interpreted legally by thermo-dynamics nor thermo chemistry4 ,while the legal principles are as yet unsettled1 the tenor of current decisions may be summed up as follows3 ,if explosion cause fire1 and fire cause loss1 it is a loss by fire as proximate cause2 and if fire cause explosion1 and explosion cause loss1 it is a loss by fire as efficient cause4 ,smoke1 an imperfect combustion1 damages1 in an insurance sense1 as well as flame1 which is perfect combustion2 and where there is concurrence of expanding air with expanding combustion1 the law settles on the basis of a common account4 ,it's all heat as a mode of motion4 ,explosions are the resultants of elemental gases1 vaporization1 comminution1 contact of different substances1 as well as of the specifically named explosives4 ,with new processes in manufacture1 involving chemical and mechanical transformations1 and other uses of new substances and new uses of old substances1 explosions increase4 ,the flour-dust of the miller1 the starch-dust of the confectioner1 increase in fineness and quantity1 and they explode2 so does the hop-dust of the brewer4 ,in #ahdd1 for the first time1 ,professors ,faraday and ,lyell1 employed by the ,british government1 discovered that explosion in bituminous coal mines was the quickening of the comparatively slow burning of the fire-damp by the almost instantaneous combustion of the fine coal-dust present in the mines4 ,the flyings of the cotton mill do not explode1 but flame passes through them with a rapidity almost instantaneous1 yet not sufficient to exert the pressure which explodes2 the dust of the wood planer and sawer only as yet makes sudden puffs without detonating force4 ,naphtha vapor and benzine vapor are getting into all places4 ,one of the latest introductions is naphtha extracting oil from linseed1 and then volatilized by steam superheated to #djj ,f4 ,this combination reminds us1 as to effectiveness1 of the combination at the recent ,kansas ,city fire1 when cans of gunpowder and barrels of coal oil both went up together4 ,but it is the unsuspected causes of explosion which make the great trouble1 and prominent among these is conflagration as itself the cause of explosion1 and such explosion may develop gases which are non-supporters of combustion as well as those which are inflammable4 ,you throw table salt down a blazing chimney to set free the flame-suppressing hydrochloric acid1 you discharge a loaded gun up a blazing chimney to put out the fire by another agency2 still the salt1 with certain combinations1 may be explosive1 a resinous vapor may be combustive in a hydrochloric atmosphere1 and gunpowder isn't harmless when thrown upon a blaze--in fact1 our common fire-extinguisher1 water1 has its explosive incidences as liquid as well as vapor4 ,gases explosive in association may be set free by the temperature of a burning building and get together4 ,in respect to the old conundrum1 ,will saltpetre explode8 ,mr4 ,a4 ,a4 ,hayes1 ,prof4 ,silliman1 and ,dr4 ,hare's views were1 as to the explosions in the ,new ,york fire of #ahde1 that in a closed building having niter in one part and shellac or other resinous material in another1 the gaseous oxygen generated from the niter and the carbureted hydrogen from the resins mingling by degrees would at length constitute an explosive mixture4 ,a brief consideration of specific explosives uniting may serve to illustrate this phase of the subject4 ,though the explosion of gunpowder is the result of a chemical change whereby carbonic acid gas at high tension is evolved 7due to the saltpeter and the charcoal71 the effect and rapidity of action are greatly promoted by the addition of sulphur4 ,on the contrary1 dynamite1 now so important1 and various similar explosives1 are but mixtures of nitro-glycerine with earthy substances1 in order to diminish and make more manageable the development of the rending force of the base4 ,the explosive power of any substance is the pressure it exerts on all parts of the space containing it at the instant of explosion1 and is measured by comparing the heat disengaged with the volume of gas emitted1 and with the rapidity of chemical action4 ,in the case of gunpowder1 the proper manipulation and division of the grains is important1 because favoring rapid deflagration2 but in a purely chemical explosion1 each separate molecule is an explosive1 and the reaction passes from the interior of one to the interior of another1 suddenly driving the atoms much further apart than their naturally infinitesimal vibrations4 ,purely chemical explosives like nitro-glycerine1 gun-cotton1 the picrites1 and the fulminates1 present a terrible danger from the unknown mode of the new union of atoms1 and reaction of the particles within themselves1 in spontaneous explosions happening in irregular manner4 ,some curious circumstances attend the manufacture and use of gun-cotton1#a nitro-glycerine1 and dynamite4 ,baron von ,link1 in his system of the artillery use of gun-cotton1 diminishes the danger of sudden explosion by twisting the prepared cotton into cords or weaving it into cloth1 thereby securing a more uniform density4 ,mr4 ,abel's mode of making gun-cotton1 which explosive is now used more than any other by the ,british government1 includes drying the damp prepared cotton upon hot plates1 freely open to the air4 ,if ignited by a flame1 however1 in an unconfined place1 gun-cotton only burns with a strong blaze1 but if confined where the temperature reaches #cdj ,f41 it explodes with terrific violence4 ,somewhat similar is the action of nitro-glycerine and dynamite1 which simply burn if ignited in the open air1 while the same substance will explode through a very slight concussion or by the application of the electric spark2 a red-hot iron1 also1 if applied1 will explode them when a flame will not4 ,with care1 nitro-glycerine can be kept many years without deterioration2 and it has been heated in a sand-bath to #hj ,c4 for a whole day without explosion or alteration4 ,one curious experiment is deserving of mention3 ,if a broad-headed nail be partly driven into pine wood1 and then some pieces of dynamite placed on the head of the nail1 the latter may be struck hard blows with a wooden mallet without exploding the dynamite so long as the nail will continue to enter the wood4 ,footnote #a3 ,the purest gun-cotton may be regarded as a cellulose1 in which three atoms of hydrogen are replaced by three molecules of peroxide of nitrogen4 ,taking gunpowder as the unit1 picrate of potash 7picric acid and potassium7 has five times more force1 gun-cotton seven and a half times1 and nitro-glycerine ten times more force4 ,there are others still more powerful1 but less known and used1 and some explosives are quite uncontrollable and useless4 ,but the particular object of these remarks is to refer to articles of merchandise non-explosive under general conditions1 but so in particular circumstances1 as the two fire-extinguishers1 water and salt1 are explosive under given conditions4 ,the memorable fire which1 in ,july1 #ahej1 destroyed three hundred buildings in ,philadelphia1 upon ,delaware avenue1 ,water1 ,front1 and ,vine streets1 was largely extended by explosions of possibly concealed or unknown materials1 the presence of the generally recognized explosives being denied by the owners of the properties4 ,the germ of the first knowledge of an explosive was probably the accidental discovery1 ages ago1 of the deflagrating property of the natural saltpeter when in contact with incandescent charcoal4#a ,although much manipulation is deemed necessary to form the close mechanical mixture of the materials of gunpowder1 it has never been proved that such intimate previous union is necessary to precede the chemical reaction causing explosion2 indeed1 some explosions in powder works1 before the mixture of the materials1 or just at its commencement1 seem to point to the contrary4 ,it is also certain that in the manufacture of gunpowder the usual nitrate of potassium 7saltpeter7 can be replaced by the nitrates of soda1 baryta1 and ammonia1 also by the chloride of potassium2 charcoal by sawdust1 tan1 resin1 and starch2 and though a substitute for sulphur is not easily found1 the latter1 or a similar substance1 is not an absolute necessity in the composition of gunpowder4#b ,footnote #a3 ,encyclopdia ,britannica1 new edition1 viii1 p4 #hjf4 ,footnote #b3 ,vide ,abel's ,experiments in ,gunpowder1 as detailed in ,phil4 ,trans4 ,eoy4 ,soc1 #ahgd4--,vide also ,bull4 ,soc4 d',encouragement1 ,nov41 #ahhj1 p4 #fcc1 ,sur les ,explosives4 ,the generally received theory of the chemical action which makes gunpowder explosive is that it is due to the superior affinity of the oxygen of the niter 7,,kno#c7 for the carbon of the charcoal1 and the production of carbonic acid gas 7,,co#b7 and carbonic oxide 7,,co7 suddenly and in great volume4 ,the latter extinguishes flame as well as the former1 unless its own flammability is supported by the oxygen of the atmosphere until the degree of oxygenation ,,co#b is reached4 ,considering that water 7,h#b,o7 is composed of two volumes of hydrogen and one of oxygen1 and that under an enormously high temperature and the excessive affinity of oxygen gas for potassium or sodium 7freed from nitrate union71 dissociation of the water may be possible1 aided by its being in the form of spray and steam1 we would hesitate to deny that an explosive union of suitable crude salts could occur during the burning of a building containing them when water for extinguishment was put on4 ,any one who has seen the brilliance with which potassium and sodium burn upon water can easily imagine how such strong affinity of oxygen for these substances might aid in severing its union in water in their presence and under extraordinary heat4 ,it might be safe so say that the presence of water under very high temperature may be as aidful to form an explosive among such salts as have been named1 as sulphur is for the rapid combustion of gunpowder4 ,in the review for ,august1 #ahfb 7,saltpeter ,deflagrations in ,burning ,buildings and ,vessels--,water as an ,explosive ,agency71 it was shown that ,mr4 ,boyden's experiments in #ahfa-fb proved that explosions would occur when water was put upon niter heated alone1 and stronger explosion from niter1 drywood1 and sulphur2 also explosion when melted niter was poured on water4 ,the following points we reproduce for comparison3 ,if common salt be heated separately to a bright heat1 and water at #aej ,f4 poured on it1 an explosion will occur4 ,niter mixed with common salt1 placed upon burning charcoal1 and water added1 produce a stronger explosion than salt alone4 ,heating caustic potash to a white heat1 and adding warm or hot water1 produces explosion4 ,at a ,boston fire small explosions were observed upon water touching culinary salt highly heated4 ,anthracite coal and niter heated in a crucible exploded when sea water was poured on them4 ,the production of explosion by the putting of water on nitrate of potassium and chloride of sodium arises from the union1 at high temperature1 of the oxygen of the water with the potash and soda4 ,of the three liberated gases1 hydrogen only is inflammable1 and the other two suffocative of flame2 but together the nitrogen and chlorine are not to be undervalued1 for chloride of nitrogen is ranked as the most terrible and unmanageable of all explosives4 ,chlorine is a great water separator1 but in the present case its affinity for hydrogen would result in hydrochloric acid1 a fire extinguisher4 ,what happens in chemical experiment may be developed on a large scale in burning grocery1 drug1 or drysalters' stores1 when great quantities of materials1 such as just mentioned1 including common salt1 almost always present1 are heated most intensely1 and then subjected to the action of water in heavy dashes1 or in form of spray or steam4 ,picric acid1 the nature of which we have several times previously mentioned1 and which explodes at #fjj ,f4 7only #bh above gunpowder71 may also be an element in such explosions during fires4 ,its salts form1 in combinations1 various powerful explosives1 much exceeding gunpowder in force2 and they have been used to a considerable extent in ,europe4 ,picric acid1 now much employed by manufacturers and dyers for obtaining a yellow color1 is always kept in store largely by drysalters and druggists1 and generally by dyers1 but in smaller quantity4 ,in a very destructive fire which occurred in ,liverpool1 ,eng41 in ,october1 #ahgd1 involving the loss of several fire-proof stores1 repeated explosions of the vapor of turpentine rent ponderous brick arched vaults1 and exposed to the flames stocks of cotton1 etc41 in the stories above4 ,this conflagration was started by the carelessness of an employee in snuffing a tallow candle with his fingers and throwing the burning snuff into the open bung-hole of a sample barrel of turpentine1 of which liquid there were many hundreds of barrels on storage in the buildings4 ,turpentine vapor united with chlorine gas may not produce explosion1 but by spreading flames almost instantly throughout the burning buildings1 such burnings have practically equaled1 if not excelled1 explosions1 which may sometimes be fire-extinguishers4 ,in such cases detonation may be prevented by there being ample space to receive the suddenly ignited vapor1 lessening the tension of it1 but carrying the flames much more rapidly than otherwise to inflammable materials at great distance4 ,if disastrous results have arisen from the vapor of turpentine as a fire spreader in vaults without windows1 it is possible that if a quantity of hot water were suddenly converted into steam in closely confined spaces1 effects of pressure might be observed1 less destructive perhaps1 but resembling those which other explosives might produce4 ,if the immense temperature attained in some conflagrations be considered--sufficient to melt iron and vitrify brick--it is possible to conceive of water as being instantly converted into steam4 ,even a very small quantity of water thus expanded could produce most disastrous results4 ,while such formation of steam1 if it happened1 would certainly extinguish most flames in direct contact1 the general phenomena shown would be explosive4 ,a curious circumstance occurred at the ,broad street 7,n4,y47 fire in #ahde1 previously mentioned4 ,the fire extended through to ,broadway1 and almost to ,bowling ,green4 ,a shock like a dull explosion was heard1 and by many this was attributed to the effects of gunpowder and saltpeter4 ,several firemen were1 at the moment of the shock1 on the roof of the burning building1 when the whole roof was suddenly raised and then let down into the street1 carrying the men with it uninjured4 ,one of the firemen described the sensation as if the roof had been first hoisted up and then squashed down4 ,query3 ,was this like the common lifting and falling back of the loose lid of a tea-kettle containing boiling water8 ,was it from steam--at a low pressure perhaps--seeking vent through the roof in like manner to the raising of the kettle-lid8 ,without dilating on this part of the subject1 we mention it as a possible cause of minor explosions--doubtless to become better known in future4 ,it may even be that explosions happening from steam acting in close spaces may have been attributed to gunpowder1 or to niter and other salts1 separate1 but suddenly caused to combine in chemical reaction4--,american ,exchange and ,review4 99 99 99 99 99 ,,carbon4--,,symbol ,c4--,,combining ,,weight #ab4 ,by ,t4,a4 ,,pooley1 ,b4,sc41 ,f4,c4,s4 ,this element1 which next deserves our attention1 is one of great importance and wide distribution2 it occurs in nature in both the free and the combined states1 and the number of compounds which it forms with other elements is very large4 ,unlike the previous elementary bodies we have studied1 carbon is only known to us in the solid form when free1 although many of its combinations are gaseous at the ordinary temperature and pressure4 ,carbon is known to exist in several different physical states1 thus illustrating what chemists call allotropism1 which means that substances of identical chemical composition sometimes possess altogether different outward and physical appearances4 ,thus the three states in which pure carbon exists1 viz41 diamond1 graphite1 or plumbago1 and charcoal are as different as possible1 and yet chemically they are all exactly the same substance4 ,the diamond is the purest carbon1 and occurs in the crystalline form known as a regular octahedron2 the diamond is one of the hardest substances known1 and is therefore1 utilized for cutting glass2 it has also a very high specific gravity1 namely1 #c4e1 which means that it is three and a half times heavier than water1 and it is far heavier than any of the other allotropic modifications of carbon4 ,graphite or plumbago1 the second form in which carbon occurs1 is widely distributed in nature1 and the finer qualities are known as black lead1 although no lead enters into their composition1 as they are composed of carbon almost as pure as the diamond2 the specific gravity of graphite is only #b4c4 ,charcoal1 the third allotropic modification of carbon1 is by far the most common1 and is formed by the natural or artificial disintegration of organic matters by heat2 we thus have formed wood charcoal1 animal charcoal1 lamp-black1 and coke1 all produced by artificial means1 and we may also class with these coal1 which is a natural product1 and which contains from #he to #ie per cent4 of pure carbon4 ,wood charcoal is made by heating wood in closed vessels or in large masses1 when all the hydrogen1 oxygen1 and nitrogen are expelled in the gaseous state1 and the carbon is left mixed with the mineral constituents of the wood2 this form of carbon is very porous and light1 and is used in a number of industrial processes4 ,animal charcoal1 as its name implies1 is the carbonaceous residue left on heating any animal matters in a retort2 and contains1 in addition to the carbon1 a large proportion of phosphates and other mineral salts1 which1 however1 can be extracted by dilute acids4 ,animal charcoal possesses to a remarkable degree the property of removing color from solutions of animal and vegetable substances1 and it is used for this purpose to a large extent by sugar refiners1 who thus decolorize their dark brown sirups2 in the manufacture of glucose and saccharums for brewers' use1 the concentrated solutions have to be filtered through layers of animal charcoal in order that the resulting product may be freed from color4 ,the decolorizing power of animal charcoal can be easily tested by any brewer1 by causing a little dark colored wort to filter through a layer of this material2 after passing through once or twice1 the color will entirely disappear1 or at all events be greatly reduced in intensity4 ,animal charcoal also absorbs gases with great avidity1 and on this account it is utilized as a powerful disinfectant1 for when once putrefactive gases are absorbed by it1 they undergo a gradual oxidation1 and are rendered innocuous1 in the same way animal charcoal is a valuable agent for purifying water1 for by filtering the most impure water through a bed of animal charcoal nearly the whole of the organic impurities will be completely removed4 ,lamp-black is the name given to those varieties of carbon which are deposited when hydrocarbons are burned with an insufficient supply of oxygen2 thus the smoke and soot emitted into our atmosphere from our furnaces and fireplaces are composed of comparatively pure carbon4 ,coal is an impure form of carbon derived from the gradual oxidation and destruction of vegetable matters by natural causes2 thus wood first changes into a peaty substance1 and subsequently into a body called lignite1 which again in its turn becomes converted into the different varieties of coal2 these changes1 which have resulted in the accumulation of vast beds of coal in the crust of the earth1 have been going on for ages4 ,there are very many different kinds of coal2 some are rich in hydrogen1 and are therefore well adapted for making illuminating gas1 while others1 such as anthracite1 are very rich in carbon1 and contain but little hydrogen2 the last named variety of coal is smokeless1 and is therefore largely used for drying malt4 ,carbon occurs in nature also in a combined state2 limestone1 chalk1 and marble contain #ab per cent4 of this element4 ,it is also present in the atmosphere in the form of carbonic acid1 and the same compound of carbon is present in well and river waters1 both in the free state and combined with lime and magnesia4 ,all animal and vegetable organisms contain a large proportion of carbon as an essential constituent2 albumen contains about #ec per cent41 alcohol contains #eb per cent41 starch #dd per cent41 cane sugar #db per cent41 and so on4 ,the presence of carbon in the large class of bodies known to chemists as carbohydrates1 of which starch and sugar are prominent examples1 can be easily demonstrated4 ,if a little strong sulphuric acid be added to some powdered cane sugar in a glass1 the mass will soon begin to darken in color and swell up1 and in the course of a few minutes a mass of black porous carbon will separate1 which can be purified from the acid by repeated washings2 the sugar is composed of carbon1 hydrogen1 and oxygen1 the two last-named elements being present in the exact proportion necessary to form water2 the sulphuric acid having a strong affinity for water1 removes the hydrogen and oxygen1 and the carbon is then left in a free state4 ,carbon forms two compounds with oxygen--carbon monoxide1 commonly called carbonic oxide1 and carbon dioxide1 commonly called carbonic acid2 and the last-named1 being of most importance1 will be studied first4 ,carbon ,dioxide1 or ,carbonic ,acid1 ,symbol ,,co#b4--;,carbonic acid occurs1 as we have already stated1 in large quantities in combination with lime and magnesia1 forming immense rock formations of limestone1 chalk1 marble1 dolomite1 etc42 it also issues in a gaseous state from volcanoes1 and it is always present in small quantities in the atmosphere2 it is found dissolved in well and river waters1 and it is a product of the respiration of animals4 ,brewers also are well aware of the existence of this body1 for it is evolved in enormous quantities during the alcoholic fermentation of saccharine fluids4 ,when carbonaceous substances are burnt the bulk of the carbon is converted into carbonic acid1 and thus our furnaces and fireplaces are continually emitting enormous quantities of carbonic acid into the atmosphere4 ,with these different sources of supply it might reasonably be thought that carbonic acid would be gradually accumulating in our atmosphere2 the breathing of animals1 the eruption of volcanoes1 the combustion of fuel1 and the fermentation of sugar1 are ever going on1 and to a fast-increasing extent with the progress of civilization1 and yet the proportion of carbonic acid in our atmosphere is no greater now than it was at the earliest time when exact chemical research determined its presence and quantity4 ,a counteracting influence is always at work2 nature has beautifully provided for this by causing plants to absorb carbonic acid1 holding some of the carbon1 and allowing the oxygen to escape again into the atmosphere to restore the equilibrium of purity4 ,this mutual evolution and absorption of carbonic acid is continually going on2 occasionally there may be either an excess or a deficiency in a particular place1 but fortunately any irregularity in this respect is soon overcome1 and the air retains its original composition1 otherwise animal life on the face of the globe would be doomed to gradual but sure extinction4 ,carbonic acid can be prepared for experimental purposes by causing dilute hydrochloric acid to act upon fragments of marble placed in a bottle with two necks1 into one neck of which a funnel passing through a cork is fixed1 and into the other a bent tube for conveying the gas into any suitable receiver4 ,the evolution of carbonic acid by this method is rapid1 but easily regulated1 and the gas may be purified by causing it to pass through some water contained in another two-necked bottle1 similar to the generator4 ,the chemical change involved in this decomposition is expressed by the following equation3 ,ca,c,o#c #b;,h,cl ,,co#b ,h#b,o ,ca,cl#b ,calcium ,hydrochloric ,carbonic ,water4 ,calcium ,carbonate4 ,acid4 ,acid4 ,chloride4 ,by referring to the table of combining weights given in a previous paper1 it will be seen that #ajj parts of calcium carbonate will yield #dd parts of carbonic acid4 ,instead of hydrochloric acid any other acid may be used1 and in the practical manufacture of carbonic acid for aerated waters sulphuric acid is the one usually employed4 ,carbonic acid is colorless and inodorous1 but has a peculiar sharp taste2 it is half as heavy again as air1 its exact specific gravity being #aebi2 one hundred cubic inches weigh #dg4bf grains4 ,it is uninflammable1 and does not support combustion or animal respiration4 ,under a pressure of about #ch atmospheres1 at a temperature of #cb ,f41 carbonic acid condenses into a colorless liquid1 which may also be frozen into a compact mass resembling ice1 or into a white powder like snow4 ,carbonic acid is soluble in water1 and at the ordinary pressure and temperature one volume of water will hold in solution one volume of the gas2 under increased pressures1 far larger quantities of the gas can be held in solution1 but this is rapidly evolved as soon as the excess of pressure is removed4 ,upon this property the manufacture of aerated waters depends4 ,the presence of free carbonic acid can be easily detected by causing the gas to pass over the surface of some clear lime-water4 ,if any be present a white film of carbonate of lime will at once be formed4 ,in testing carbonic acid in a state of combination1 the gas must first be liberated by acting upon the substance with a stronger acid1 and then applying the lime-water test4 ,the presence of large quantities of carbonic acid in a gaseous mixture can be readily detected by plunging into the vessel a lighted taper1 which will be immediately extinguished4 ,this ought always to be adopted in a brewery1 where many fatal accidents have happened through workmen going down into empty fermenting vats and wells without first taking this precaution4 ,the presence of carbon in this colorless gas can be demonstrated by causing some of it to pass over a piece of the metal potassium placed in a hard glass tube1 and heated to dull redness2 the potassium then eagerly combines with the oxygen1 forming oxide of potassium1 and the carbon is liberated and can be separated in the form of a black powder by washing the tube out with water4 ,carbon ,monoxide1 or ,carbonic ,oxide4 ,symbol ,,co4--,this is formed when carbon is burnt with an insufficient supply of oxygen1 or when carbonic acid gas is passed over some carbon heated to redness4 ,this gas is continually being formed in our furnaces and fire-places2 at the lower part of the furnace1 where the air enters1 the carbon is converted into carbonic acid1 which in its turn has to pass through some red-hot coals1 so that before reaching the surface it is again converted into carbonic oxide2 over the surface of the fire this carbonic oxide meets with a fresh supply of oxygen1 and is then again converted into carbonic acid4 ,the peculiar blue lambent flame often observed on the surface of our open fire-places is due to the combustion of carbonic oxide1 which has been formed in the way we have just described4 ,carbonic oxide is a colorless1 tasteless gas1 which differs from carbonic acid by being combustible1 and by not having any action on lime water4--,brewers' ,guardian4 99 99 99 99 99 ,,seyfferth',s ,,pyrometer4 ,the thermometers and pyrometers usually employed are almost all based on the expansion of some fluid or other1 or upon that of different metals4 ,the first can only be constructed with glass tubes1 thus rendering them fragile4 ,the second are often wanting in exactness1 because of the change that the molecules of a solid body undergo through heat1 thus preventing them from returning to exactly their first position on cooling4 ,illustration3 ,fig4 #a4--,pyrometer with ,electric ,indicator4 ,the principle of the ,seyfferth pyrometer is based on the fact that the pressure of saturated vapors1 that is1 vapors which remain in communication with the liquid which has produced them1 preserves a constant ratio with the temperature of such liquid1 while1 on the other hand1 the temperature of the latter when shut up in a vessel will correspond exactly with that of the medium into which it is introduced4 ,illustration3 ,fig4 #b4--,method of ,mounting by means of a cone on vacuum apparatus4 ,illustration3 ,fig4 #c4--,mounting by means of a sleeve on vacuum apparatus4 ,this instrument is composed of a metallic vessel or tube which contains the liquid to be exposed to heat1 and of a spring manometric apparatus communicating with the tube1 and by means of which the existing temperature is shown4 ,the dial may be provided with index needles to show minimum and maximum temperatures1 as well as be connected with electric bells 7,fig4 #a7 giving one or more signals at maximum and minimum temperatures4 ,the vessel to contain the liquid may be of any form whatever1 but it is usually made in the shape of a straight or a bent tube4 ,the nature of the metal of which the latter is made is subordinate1 not only to the maximum temperature to which the apparatus are to be exposed1 but also to the nature of the liquid employed4 ,it is of either yellow metal or iron4 ,to prevent oxidation of the tube1 when iron is employed1 it is inclosed within another iron tube and the space between the two is filled in with lead4 ,when the apparatus is exposed to a high temperature the lead melts and prevents the air from reaching the inner tube1 so that no oxidation can take place4 ,pyrometers filled with ,ether4-,these are tubular1 and constructed of yellow metal1 and are graduated from #ce ,c4 to #abj4 ,they are used for obtaining temperatures in vacuum apparatus1 cooking apparatus1 diffusion apparatus1 saturators1 etc4 ,figs4 #b1 #c1 #d1 and #e1 show the different modes of mounting the apparatus according to the purpose for which it is designed4 ,pyrometers filled with distilled water are used for ascertaining temperatures ranging from #ajj to #bfe ,c41 #hj to #baj ,r41 or #bab to #eaj ,f4 ,pyrometers filled with mercury are constructed for ascertaining temperatures from #cfj to #gej ,c4 ,illustration3 ,fig4 #d4--,mounting on horizontal pipes by thread on the tube4 ,illustration3 ,fig4 #e4--,mounting by means of a clasp in reservoirs4 ,,application ,,of ,,the ,,pyrometer ,,in ,,bone ,,black ,,furnaces4 ,the temperature necessary for the complete carbonization of the organic substances of animal charcoal is from #dcj to #ejj ,c4 ,in order to transmit this temperature from the cylinder to the charcoal it is indispensable that the air surrounding the cylinder be heated to #dhj to #eej4 ,if the heating of the animal black exceeds #ejj the product hardens1 diminishes in volume1 and loses its porosity4 ,there are two methods of ascertaining the temperature of the red-hot bone black by means of the pyrometer3 ,first1 by inserting the tube of the instrument into the black4 7,fig4 #f1 a47 ,second1 by finding the temperature of the hot gases in the furnaces 7,fig4 #f1 b474 ,in the first case1 the plunge tube should be of sufficient length to allow its extremity to penetrate to the very bottom layer of the red-hot black4 ,this mode of direct control of the temperature of the black is only employed for ascertaining the work accomplished by the furnace1 that is to say1 the ratio existing between the temperature of the hot air surrounding the cylinder and the black itself4 ,this calculation being effected1 it is useless to note the differences of temperature which arise in the spaces between the cylinders of which the furnace is composed4 ,the position that the pyrometer should occupy is subordinate to the construction of the furnace4 ,fig4 #f shows the type which is most employed4 ,illustration3 ,fig4 #f4--,the ,pyrometer mounted on a bone-black furnace4 ,in a furnace with lateral fire-place1 cc are the heating cylinders1 and dd the cooling cylinders4 ,c ,d is the plate on which are mounted vertically the former1 and from which are suspended the latter1 b shows the pyrometer1 the length of which must be such that the manometric apparatus shall stand out one or two inches from the external surface of the wall1 while its tube1 traversing the wall1 shall reach the very last row of heating cylinders4 ,that the apparatus may form a permanent regulator for the stoker it is well to adapt to it an arrangement permitting of a graphic control of the work accomplished and signaling by means of an electric bell when the temperature of the gases in the furnace descends below #dhj ,c4 or rises above #eej ,c4 ,,application ,,of ,,the ,,apparatus ,,to ,,brick ,,furnaces ,,and ,,in ,,the ,,manufacture ,,of ,,chemical ,,products4 ,the operation of heating brick furnaces is generally performed according to empirical methods1 the temperature having to vary much according to the products that it is desired to obtain4 ,it is necessary1 however1 for a like product to maintain as uniform a temperature as possible4 ,these observations are particularly applicable to continuous furnaces such as annular brick furnaces1 etc41 in which a uniformity of temperature in the different chambers is of vital importance to perfect the baking4 ,in these furnaces the tube of the pyrometer is inserted through one of the apertures at the top1 as shown in ,fig4 #g4 ,the dial is graduated up to #gej1 which is more than sufficient1 since the temperature of the upper part of a compartment fully exposed to the heat rarely exceeds #fgj to #fhj ,c4 ,illustration3 ,fig4 #g4--,the ,pyrometer mounted on a brick furnace4 99 99 99 99 99 ,,manufacturers' ,,soaps ,,and ,,their ,,production4 ,by ,w4 ,j4 ,,menzies4 ,potash soaps are generally superior to soda soaps for most purposes1 but more especially in washing wool and woolen goods4 ,the difference between the use of a potash and a soda soap for these purposes is very marked4 ,potash lubricates the fiber of the wool1 renders it soft and silky1 and to a certain extent bleaches it2 soda1 on the other hand1 has a tendency to turn wool a yellow color1 and renders the fiber hard and brittle4 ,it cannot be too strongly insisted upon1 therefore1 that nothing but a potash soap 7or some form of potash in preference to soda if an alkali alone is employed7 should be used in washing wool in any form--either manufactured or unmanufactured4 ,this is fully borne out by nature1 who invariably assimilates the most appropriate substances4 ,wool when growing in its natural state is lubricated and protected by a sticky substance called grease or suinte2 this consists to the extent of nearly half its weight of carbonate of potash1 hardly a trace of soda being present4 ,it is very evident1 therefore1 that potash must be more suitable for washing wool than soda1 as the teaching of nature is always correct4 ,there are certain prejudices against the use of potash soap1 which have1 to a great extent1 prevented its more extensive use4 ,many consumers of soap fancy that because a potash soap is soft it necessarily must contain more water than a soda soap2 this1 however1 is quite an erroneous notion4 ,a potash soap is soft1 because it is the nature of all potash soaps to be so1 just in the same way that on the other hand all soda soaps are hard4 ,as an actual fact a good potash soap contains less water than many quite hard soda soaps that are now in the market4 ,another reason is that soapmakers have had every interest in using soda in preference to potash--particularly when latterly soda has been so cheap4 ,potash not only is a more expensive alkali1 but its combining equivalent is greatly against it as compared with soda2 that is to say1 that thirty-one parts of actual or anhydrous soda will saponify as much tallow or oil as forty-seven parts of anhydrous potash4 ,it will be evident1 therefore1 that the use of potash instead of soda is decidedly more advantageous to the soapboiler1 and more particularly in the present age1 when the demand is for cheap articles1 often quite without regard to the quality or purpose for which they are to be used4 ,as far as consumers are concerned1 this has been a mistake4 ,potash soap1 though it may cost more1 is in most cases actually the most economical4 ,soap is never used in exact chemical equivalents1 but an excess is always taken4 ,potash soap is much more soluble than a soda soap2 it therefore penetrates the fiber1 and consequently removes dirt and grease much more quickly4 ,notwithstanding1 also1 that its chemical combining equivalent is greater than that of soda1 it is1 nevertheless1 the strongest base1 and always combines with any substance in preference to soda4 ,for these reasons--probably combined also with the fact that in the whole realm of the animal and vegetable kingdoms1 to which all textile fabrics belong1 potash is more naturally assimilated than soda--a smaller quantity of potash soap will do more practical work than a larger quantity of soda soap4 ,there are other reasons why potash soaps have not been used2 originally soft soap was made either with fish oil or olive oil4 ,fish oil is objectionable1 as the strong smell imparted to the soap renders it unfit for many finishing purposes4 ,nothing can be better than olive oil soap1 but it is a costly article1 and only can be used for finer purposes4 ,there are now1 however1 many of the seed oils that are much cheaper4 ,linseed1 rape seed1 and cotton seed all produce a good soap4 ,cotton seed oil is particularly suitable for the purpose2 the manufacture of this oil during the last few years has been brought to great perfection1 and the cost is now much less than that of tallow or of any other seed oil4 ,it is now difficult to distinguish a well refined cotton seed oil from olive oil2 it is therefore in every way suitable for making soft soap4 ,one of the chief causes1 however1 why potash soap has not been more generally made is that a convenient form of potash has been unobtainable4 ,for many years the only source of potash was from the ashes of burnt trees4 ,these ashes are collected1 mixed with lime1 lixiviated1 and the resulting lye boiled down4 ,the result is a very impure form of potash1 also of a very variable composition1 depending upon the trees used for the purpose4 ,canada has been the principal source of supply of this form of potash2 hence the commercial name of ,montreal potashes4 ,the classification of firsts1 seconds1 and thirds is from the inspection at the warehouse there2 this1 however1 is exceedingly superficial1 the ashes being simply tested for their alkaline strength1 with no discrimination between potash and soda1 which is a difficult and delicate chemical test4 ,soda being now far cheaper than potash1 and also the alkaline equivalent1 as previously explained1 being greatly in favor of soda1 there has been every inducement to enterprising producers of ashes to adulterate them with soda1 which1 in many cases1 has been largely done4 ,another source of potash has been beetroot ashes1 very similar to wood ashes1 and also ,german carbonate of potash1 which latter about corresponds to a common soda ash1 as compared with caustic soda2 with these articles1 a tedious boiling process1 very similar to the old process for the production of hard soap1 had to be adopted1 the ashes1 or carbonate of potash1 previously being dissolved and causticized with lime by the soap maker4 ,the production of a first-class soft soap was also a very difficult operation1 as the impurities and soda contained varied considerably1 often causing the boil to go wrong and give considerable trouble to the soapboiler4 ,during the last two years1 however1 caustic potash has been introduced1 that manufactured by the ,greenbank ,alkali ,co41 of ,st4 ,helens1 being very nearly pure4 ,with this article there is no difficulty in producing a pure potash soap1 either for wool scouring1 fulling1 or sizing1 by a cold process very similar to that described for the production of hard soda soap with pure powdered caustic soda4 ,the following directions will produce an excellent soap for wool scouring3 ,fifty pounds of ,greenbank pure caustic potash are put into eight gallons of soft water2 the potash dissolves immediately1 heating the water4 ,this lye is allowed to cool1 and then slowly added1 with continual mixing1 to #bj gallons of cotton seed oil1 mixed with #bj pounds of melted tallow1 the whole being brought to a temperature of about #ij ,f4 ,after stirring for some minutes1 so as to completely combine the lye and oil1 the mixture is left for two days in a warm place1 when a slow and gradual saponification of the mass takes place4 ,if when examined the oil and lye are then found not completely combined1 the stiff soap is again stirred and left two days1 when the saponification will be found complete1 the result being the formation of about #ccj pounds of very stiff potash soap1 each pound being equal to about two pounds of the ordinary fig soap sold4 ,the requisite quantity is thrown into the scouring vat with about five per cent of its weight of refined pearl ash to increase the alkali present1 the weight depending somewhat upon the kind of wool washed on purpose for which the soap is required4 ,if the wool is very dirty or greasy1 rather a stronger soap is sometimes advisable4 ,this can easily be attained by reducing the quantity of oil used to #ah gallons4 ,the advantages to be gained by the wool scourer or other consumer making his own potash soap are that a pure1 uniform article can always be thus produced at a less cost than that at which the soap can be bought4 ,potash soap1 like soda soap now sold1 is much adulterated1 in addition to all the impurities originally contained in the potash used1 and which1 unlike soda soap1 cannot be separated by any salting process4 ,many other adulterations are added to increase the weight and cheapen the cost4 ,silicate of potash1 resin1 and potato flour are all more or less employed for this purpose1 to the gain of the soap maker and at the expense of the consumer4 ,the production of potash soap for fulling and sizing1 and the most suitable oils and tallow for the production of the various qualities required for these purposes1 must be reserved for the next issue4--,textile ,manufacturer4 99 99 99 99 99 ,,the ,,preparation ,,of ,,perfume ,,pomades4 ,we have1 on a previous occasion1 described the process of maceration or enfleurage1 that is1 the impregnation of purified fat with the aroma of certain scented flowers which do not yield any essential oil in paying quantities4 ,at present we wish to describe an apparatus which is used in several large establishments in ,europe for obtaining such products on the large scale and within as short a time as possible4 ,the drawing gives the idea of the general arrangement of the parts rather than the actual appearance of a working apparatus1 for the latter will have to vary according to the conveniences and interior arrangements of the factory4#a ,footnote #a3 ,our illustration has been taken from ,c4 ,hofmann1 ,chemisch-technisches ,universal-,receptbuch1 #hvo1 ,berlin1 #ahgi1 p4 #bjg4 ,a series of frames with wire-sieve bottoms are charged with a layer of fat in form of fine curly threads1 obtained by pressing or rubbing the fat through a finely-perforated sieve4 ,the frames are then placed one on top of the other1 and to make the connection between them air-tight1 pressed together in a screw press4 ,a reservoir1 ,e1 is charged with a suitable quantity of the flowers1 etc41 and tightly closed with the cover1 after which the bellows are set into motion by any power most convenient4 ,scented air is thereby drawn from the reservoir1 ,e1 through the pipe1 ,g ,b1 toward the stack of frames containing the finely divided fat1 which latter absorbs the aroma1 while the nearly deodorized air is sent back to the reservoir by the pipe1 ,d1 to be freshly charged and again sent on its circuit4 ,this apparatus is said to facilitate the turning out of nearly twenty times the amount of pomade for the same number of frames and the same time1 as the old process of enfleurage4 ,it might be called the ensoufflage process4--,new ,remedies4 ,illustration3 ,,ensoufflage ,,apparatus ,,for ,,perfumes4 99 99 99 99 99 ,,organic ,,matter ,,in ,,sea-,,water4 ,at a recent meeting of the ,london ,chemical ,society1 ,mr4 ,w4 ,jago read a paper ,on the ,organic ,matter in ,sea-water4 ,on p4 #acc of the ,sixth ,report of the ,rivers ,commission1 it is stated that the proportion of organic elements in sea-water varies between such wide limits in different samples as to suggest that much of the organic matter consists of living organisms1 so minute and gelatinous as to pass readily through the best filters4 ,at the suggestion of ,dr4 ,frankland1 the author has investigated this subject4 ,the water was collected in mid-channel between ,newhaven and ,dieppe by the engineers of the ,london1 ,brighton1 and ,south ,coast ,railway in stoppered glass carboys4 ,the author has used the combustion method1 the albuminoid ammonia1 and in some cases the oxygen process of ,prof4 ,tidy4 ,to determine how the various methods of water-analysis were effected by a change of the organic matter from organic compounds in solution to organisms in suspension1 some experiments were made with hay-infusion4 ,the results confirm those of ,kingzett 7,chem4 ,soc4 ,journ41 #ahhj1 #ae74 the oxygen required first rising and then diminishing4 ,the author concludes that the organic matter of sea-water is much more capable of resisting oxidizing agents than that present in ordinary fresh waters1 and that the organic matter in sea-water is probably organized and alive4 99 99 99 99 99 ,,bacteria ,,life4 ,w4 ,m4 ,hamlet1 in a paper before the ,london ,chemical ,society1 said3 ,flasks similar to those of ,pasteur 7,etudes sur la ,biere1 p4 #ha71 holding about liter1 were used4 ,the liquids employed were ,pasteur's fluid with sugar1 beef-tea1 hay infusion1 urine1 brewers' wort1 and extract of meat4 ,each flask was about half filled1 and boiled for ten minutes1 whereby all previously existing life was destroyed4 ,the flask was then allowed to cool1 the entering air being filtered through a plug of glass wool or asbestos4 ,the flask was then inoculated with a small quantity of previously cultivated hay solution or ,pasteur's fluid4 ,hydrogen1 oxygen1 carbonic oxide1 marsh-gas1 nitrogen1 and sulphureted hydrogen1 were without effect on the bacteria4 ,chlorine and hydric peroxide 7about #g per cent1 of a #e vol4 solution7 were fatal to bacteria4 ,the action of various salts and organic acids in #e per cent1 solution was tried4 ,many1 including potash1 soda1 potassic bisulphite1 sodic hyposulphite1 potassic chlorate1 potassic permanganate1 oxalic acid1 acetic acid1 glycerin1 laudanum1 and alcohol1 were without effect on the bacterial life4 ,others--the alums1 ferrous sulphate1 ferric chloride1 magnesic and aluminic chlorides1 bleaching powder1 camphor1 salicylic acid1 chloroform1 creosote1 and carbolic acid--decidedly arrested the development of bacteria4 ,the author has made a more extended examination of the action of chloroform1 especially as regards the statement of ,mntz1 that bacteria cannot exist in the presence of #b per cent1 of chloroform1 which substance is therefore useful in distinguishing physiological from chemical ferments4 ,the author concludes that amounts of chloroform1 phenol1 and creosote1 varying from to #c per cent41 do not destroy bacteria1 although their functional activity is decidedly arrested while in contact with these reagents4 ,to use the author's words1 bacteria may be pickled in creosote and carbolic acid without being deprived of their vitality4 ,the author concludes that the substances which destroy bacteria are those which are capable of exerting an immediate and powerful oxidizing action1 and that it is active oxygen1 whether from the action of chlorine1 ozone1 or peroxide of hydrogen1 which must be regarded as the greatest known enemy to bacteria4 ,mr4 ,hamlet1 in replying to some remarks of ,messrs4 ,kingzett and ,williams1 said that in all cases the solution which he had used had been completely sterilized by exposure to a temperature of #aje for ten minutes4 ,the ,india-rubber tubing he had used was steamed4 ,carbolic acid solution must contain at least #e per cent1 of carbolic acid to be fatal to bacteria4 ,he was quite aware of the importance of distinguishing between the action of the substances on various kinds of bacteria1 and was quite prepared to admit that a treatment which would be fatal to one kind of bacterium might not injure another4 99 99 99 99 99 ,,on ,,the ,,composition ,,of ,,elephants' ,,milk4 ,footnote3 ,read before the ,american ,chemical ,society1 ,june #c1ahha4 ,by ,,chas4 ,a4 ,,doremus1 ,m4,d41 ,ph4,d4 ,noticing the recent advertisements in the city regarding the ,baby ,elephant1 it occurred to me that perhaps no analysis of the milk of this species of the mammalia had been recorded4 ,this ,i found corroborated1 for though the milk of many animals had been subjected to analysis1 no opportunity had ever presented itself to obtain elephants' milk4 ,through the courtesy of ,jas4 ,a4 ,bailey ,i was enabled to procure samples of the milk on several occasions4 ,on ,march #aj1 #ahhj1 the elephant ,hebe gave birth to the female calf ,america4 ,hebe is now twenty eight years old1 and the father of the calf1 ,mandrie1 thirty-two4 ,since the birth of the ,baby1 the mother has been in excellent health1 except during about ten days1 when she suffered from a slight indisposition1 which soon left her4 ,when born the calf weighed #bac lbs41 and in ,april1 #ahha1 weighed #ijj lbs4 ,a very fair year's growth on a milk diet4 ,at the time ,i procured the samples both mother and calf were in fine health4 ,to obtain the milk was a matter of some difficulty4 ,the calf was constantly sucking1 nursing two or three times an hour1 morning1 noon1 and night4 ,the milk could be drawn from either of the two teats1 but only in small quantity4 ,the mother gave the fluid freely enough1 apparently1 to her infant1 but sparingly to inquisitive man1 so the ruse had to be resorted to of milking one teat while the calf was at the other4 ,when ,i first examined the specimens they seemed watery1 but to my surprise1 on allowing the milk to stand1 ,i could not help wondering at the large percentage of cream4 ,the following represents approximately the daily diet of the mother3 ,three pecks of oats1 one bucket bran mash1 five or six loaves of bread1 half a bushel of roots 7potatoes1 etc471 fifty to seventy-five pounds of hay1 and forty gallons of water4 ,elephants eat continually1 little at a time1 to be sure1 but are constantly picking4 ,this habit is also observable in the way the calf nurses4 ,the first specimen of milk was procured on the morning of ,april #e1 the second on the #ith1 and the third on the #ajth4 ,the last exceeded the others in quantity1 and is therefore the fairest of the three4 ,it took several milkings to get even these1 for the calf would begin to nurse1 then stop1 and when she stopped the flow of milk did also4 ,i was assured by ,mr4 ,cross and the keeper1 ,mr4 ,copeland1 that the milk ,i obtained had all the appearances of that drawn at various times since the birth of the calf4 ,mr4 ,cross1 when in ,boston1 compared the milk with that from an ,alderney cow1 and found the volume of cream greater4 ,i endeavored to have the calf kept away from the mother for some hours1 but could not1 since she is allowed her freedom1 as she worries under restraint1 and besides1 has never been taken from the mother4 ,the calf picked at oats and hay1 but was dependent on the mother for nourishment4 ,it would have been a matter of great satisfaction to me had ,i been able to obtain a larger quantity of the milk1 or to have gained even an approximate knowledge of the daily yield1 but was obliged to content myself with what ,i could get4 ,by comparing several samples1 however1 a just conclusion regarding the quality was found4 ,the analyses of the samples gave the following results3 ,no4 ,i4 ,,ii4 ,,iii4 ,april #e1 ,april #i1 ,april #aj1 ,morning4 ,noon4 ,morning4 ,quantity1 #ai cc4 #cf cc4 #gb cc4 ,cream1 #eb-d1 vol4 #eh #fb ,reaction1 ,neutral4 ,slightly alkaline4 ,slightly acid4 ,sp4gr41 ---- ---- #ajbc4g ,in #ajj parts by weight4 ,water444444444444#fg4efg #fi4bhf #ff4fig ,solids44444444444#cb4dcc #cj4gad #cc4cjc ,fat44444444444444#ag4edf #ai4jie #bb4jgj ,solids not fat444#ad4hhg #aa4fai #aa4bcc ,casein44444444444#ad4bcf #c4fid #c4bab ,sugar444444444444#ad4bcf #g4bfg #g4cib ,ash44444444444444 #j4fea #j4feh #j4fbi ,ten grammes were taken for analysis1 and in ,no4 ,,iii4 duplicates were made4 ,it is evident from these analyses that the milk approaches the composition of cream1 yet it did not have the consistency of ordinary cream--as cream even rose upon it4 ,under the microscope the globules presented a very perfect outline1 and were beautifully even in size and very transparent4 ,the cream rose quickly1 leaving a layer of bluish tinge below4 ,the milk was pleasant in flavor and odor1 and very superior in these respects to that of many animals such as goats or camels1 and in quality equal to that of cows4 ,nor did the milk emit any rank odor on heating4 ,when ten grammes were evaporated to dryness1 the last portions of water were hard to remove1 as the residue fairly floated with oil4 ,only by long-continued application of heat1 and in analysis ,,iii4 over sulphuric acid in vacuo1 could a constant weight be obtained4 ,i would have used sand in the drying1 or ,baumhauer's method of fat extraction1 but for the small quantity of milk at my disposal and from fear of loss of fat in the latter case4 ,the fat in ,,iii4 was determined by extracting the dried residue and also with #bj c4 c4 of milk by adding alkali and shaking with ether1 removing and evaporating the ether and weighing the fat4 ,as is shown in the table the sp4 gr4 is very low1 though the solids and solids not fat are great4 ,the ash1 casein1 and sugar are in about the usual proportion4 ,the weight of casein1 it is true1 is but half that of the sugar4 ,the milk indeed shows an unusually great preponderance of the non-nitrogenized elements1 and this seems to correspond with the wants of the animal1 since fatty tissues are greatly developed in elephants4 ,according to ,mr4 ,cross1 who has had large experience with these animals1 they are fatter in the wild state than in bondage4 ,these specimens must appear as exceptional2 they may be considered by some as strippings2 but as against such a view we have the recurrence in each sample of the same characteristics in the milk and a near correspondence in the composition4 ,as may be seen from the subjoined analyses1 given by v4 ,gorup ,besanez1#a the milk belongs to the class of which woman's and mare's milk are members1 especially as regards the proportion of the non-nitrogenized to the nitrogenized elements4 ,footnote #a3 ,lehrhuch der ,physiologischen ,chemie1 pp4 #dbc and #dbd4 ,constituents4 ,woman4 ,cow4 ,goat4 ,ewe4 ,ass4 ,mare4 ,water4 #hf4bga #hd4bh #hf4he #hc4cj #hi4ja #ij4de ,solids4 #ac4gbi #ae4gb #ac4eb #af4fj #aj4ii #i4ee ,fat4 #e4cgj #e4dg #d4cd #f4je #a4he #a4ca ,casein4 #c4eg #b4ec #b4iej #e4gc #c4eg #b4ec ,albumen4 _/ #j4gh #a4bf _/ _/ _/ ,milk ,sugar4 #e4acf #d4cd #c4gh #c4if #e4db #e4je ,ash4 #j4bbc #j4fc #j4fe #j4fh _/ #j4bi ,constituents4 ,buffalo4 ,camel4 ,sow4 ,hippo- ,elephant4 potamus4 ,water4 #hj4fdj #hf4cd #ha4hj #ij4dc #ff4fig ,solids4 #ai4cfj #ac4ff #ah4bj #i4eg #cc4cjh ,fat4 #h4dej #b4ij #f4jj #d4ea #bb4jgj ,casein4 #d4dj #d4bdg #c4fg #e4cj #c4bab ,albumen4 _/ _/ _/ _/ ,milk ,sugar4 #d4eah #e4gh #f4jg #a #g4cib ,ash4 #j4hde #j4ff #j4hc #j4aa #j4fbi ,footnote #a3 ,milk ,sugar included4 ,it may be remarked that though approaching the composition of cream it still differs enough to require it to be considered milk4 ,perhaps if a larger quantity of the milk could be collected1 it would have a more watery character1 and approximate more nearly to other milks in that respect4 ,however this may be the quality of the fat deserves some attention4 ,the fat has a light yellow color1 resembling olive oil1 is very pleasant in odor and taste1 is liquid at common temperatures1 but solidifies at #ah ,c4 or #fd ,f4 ,the cow must yield a considerable quantity of milk1 since the growth of the calf has been constant1 and at the time these samples were milked the mother gave as freely to her babe as she ever had since its birth4 ,the calf having gained seven to eight hundred pounds on a milk diet in one year1 it is presumable that it had no lack of nourishment4 ,in size the ,baby compared equally with other elephants in the same menagerie1 who were known to be four and five years old4 ,from whatever standpoint1 therefore1 we view the lacteal product of these four-footed giants1 we are fully warranted in ascribing to it not only extreme richness1 but also great delicacy of flavor4 99 99 99 99 99 ,,the ,,chemical ,,composition ,,of ,,rice1 ,,maize1 ,,and ,,barley4 ,by ,j4 ,,steiner1 ,f4,c4,s4 ,rice contains much more starch1 but on the other hand1 much less albuminous matter and ash1 than maize and barley4 ,the compositions of different kinds of dried rice do not vary very much1 but as the amount of moisture in the raw grain ranges from #e to #ae per cent41 no brewer ought to buy rice without having first of all inquired with the assistance of a chemist as to the percentage of water present in the sample4 ,another point requiring attention is that of taking notice of the acidity1 which also varies a good deal for different sorts of rice4 ,in comparing the nutritive values of the three kinds of grain before us1 ,pillitz obtained the following numbers3 ,barley4 ,maize4 ,rice4 -------------- ------------- ------------------ ,air ,dried at ,air ,dried at ,air ,dried at ,with ,dry4 #ajj ,c4 ,dry4 #ajj ,c4 ,dry4 #ajj ,c4 ,husk4 ,moisture4 #ac4hh --- #ac4hi --- #ab4ea --- #ab4jj ,starch4 #ed4jg #fb4fe #fb4fi #gc4bg #gd4hh #he4da #gd4ej ,dextrin and sugar4 #e4ff #f4fg #c4eg #d4ad #a4ab #a4bf --- ,total albumen matter4 #ad4jj #af4bh #aj4fc #ab4ce #i4ai #aj4dj #g4hj ,mineral matter4 #b4cc #b4gj #a4dh #a4ga #j4hd #j4id #b4cj ,fatty matter4 #b4cj #b4fh #d4cf #e4jc #j4gh #j4hh #j4cj ,cellulose matter4 #g4gf #i4jb #c4ch #d4ej #j4fh #a4aa #c4aj ---------------------------------------- ------------------- #ajj4jj #ajj4jj #ajj4jj #ajj4jj #ajj4jj #ajj4jj #ajj4jj ,on looking over this table1 we notice that rice contains by about #bj per cent1 more starch than barley1 and by about #aj to #ab per cent1 more than maize4 ,but on the other hand1 barley and maize are richer in albuminous matter and in ash4 ,the extractive matter1 i4 e41 the part which is soluble in cold water1 is also much greater in barley and maize than in rice4 ,the extractive matter is for barley #h4g per cent41 for maize #f4c per cent41 while rice contains only #b4a per cent41 and it consists in each case of dextrin1 sugar1 the soluble part of the ash1 and of some nitrogenous matter 7soluble albumen74 ,the amount of woody fiber or cellulose is considerable for rice with its husk1 but only slight for samples without husk4 ,the seat of the mineral matter of the grain of rice is mainly in the husk1 and as this ash is very valuable as nourishment for the yeast plant1 it is an open question whether it would not be preferable to use for brewing purposes rice with its husk4 ,the comparatively largest amount of fat is contained in maize2 and as such oil is not desirable for brewing purposes1 different recommendations have been advanced for freeing the grain from it4 ,in the following table some of the mineral constituents of the three kinds of grain are compared with each other4 ,these data refer to #ajj parts of ash1 and are taken from analysis given by ,dr4 ,emil ,wolf4 #ajj parts of ,potash ,lime ,magnesia ,phosphoric ,silica grain contain acid ash4 ,barley4 #ba4i #b4e #h4c #cb4h #bg4b #b4ee p4 ct4 ,rice with husk4 #ah4d #e4a #h4f #dg4b #j4f #g4hd ,rice without husk4 #bc4c #b4i #ac4d #ea4j #c4j #j4ci ,maize4 #bg4j #b4g #ad4f #dd4g #b4b #a4db ,the excessive amount of ash in rice with its husk is very remarkable1 and as this mineral matter consists to a great extent of phosphoric acid and potash1 the larger part of it is soluble in water4 ,consequently on using rice with its husk for brewing purposes1 the yeast will be provided with a considerable amount of nutritive substance4 ,in conclusion it need hardly be mentioned that the use of rice with its husk would also be of considerable pecuniary advantage4 ,there is very little oil in the husk of rice1 as shown above by analysis1 and it is not likely that the flavor of the brew would suffer by it4--,london ,brewers' ,journal4 99 99 99 99 99 ,,petroleum ,,oils4 ,nothing is in more general use than petroleum1 and but few things are known less about by the majority of persons4 ,it is hydra-headed4 ,it appears in many forms and under many names4 ,burning fluid is a popular name with many unscrupulous dealers in the cheap and nasty4 ,burning fluid is usually another name for naphtha1 or something worse4 ,gasoline1 naphtha1 benzine1 kerosene1 paraffine1 and many other dangerous fluids which make the fireman's vocation necessary are all the product of petroleum4 ,these oils are produced by the distillation or refining of crude petroleum1 and inasmuch as the public1 especially firemen1 are daily brought into contact with them it is proper that they should know something of their properties4 ,refining as commonly practiced involves three successive operations4 ,the apparatus employed consists of an iron still connected with a coil or worm of wrought-iron pipe1 which is submerged in a tank of water for the purpose of cooling it4 ,the end of this pipe is fixed with a movable spout1 which can be transferred or switched from one to another of half a dozen pipes which come around close to it1 but which lead into different tanks containing different grades of the distillate4 ,when the still has been filled with crude oil the fire is lighted beneath it1 and soon the oil begins to boil4 ,the first products of distillation are gases which1 at ordinary temperatures1 pass through the coil without being condensed1 and escape4 ,when the vapors begin to condense in the worm the oil trickles from the end of the coil into the pipe leading to the appropriate receiving tank4 ,the first oil obtained is known as gasoline1 used in portable gas machines for making illuminating gas4 ,then1 in turn1 come naphthas of a greater or less gravity1 benzine1 high test water white burning oil1 such as ,pratt's ,astral common burning oil or kerosene1 and paraffine oils4 ,when the oil has been distilled it is by no means fit for use1 having a dirty color and most offensive smell2 it is then refined4 ,for this purpose it is pumped into a large vat or agitator1 which holds from two hundred and fifty to one thousand barrels4 ,there is then added to the oil about two per cent1 of its volume of the strongest sulphuric acid4 ,the whole mixture is then agitated by means of air pumps1 which bring as much as possible every particle of oil in contact with the acid4 ,the acid has no affinity for the oil1 but it has for the tarry substance in it which discolors it1 and1 after the agitation1 the acid with the tar settles to the bottom of the agitator1 and the mixture is drawn off into a lead-lined tank4 ,after the removal of the acid and tar1 the clear oil is agitated with either caustic soda or ammonia and water4 ,the alkali neutralizes the acid remaining in the oil1 and the water removes the alkali1 when the process of refining is finished4 ,a few refiners improve the quality of their refined oil by redistilling it after treating it with acid and alkali4 ,all distillates of petroleum have to be treated with acid and alkali to refine them4 ,there is one thing peculiar about the distillates of petroleum1 and that is that the run which follows naphtha1 which is called the middle run oil1 is the highest test oil that is made1 running as high as #aej and #afj degrees flash1 while the common oil which follows1 viz41 from #de down to #cc degrees ,baume1 will range at only about #ajj flash1 or #aae and #abj degrees burning lest4 ,an oil that will stand #ajj flash will stand #aaj burning test every time4 ,kerosene oil1 at ordinary temperature1 should extinguish a match as readily as water4 ,when heated it should not evolve an inflammable vapor below #aaj degrees1 or1 better1 #abj degrees ,fahrenheit1 and should not take fire below #abe to #adj degrees ,fahrenheit4 ,as the temperature in a burning lamp rarely exceeds #ajj degrees ,fahrenheit1 such an oil would be safe4 ,it would produce no vapors to mix with the air in the lamp and make an explosive mixture2 and1 if the lamp should be overturned1 or broken1 the oil would not be liable to take fire4 ,the crude naphtha sells at from three to five cents per gallon1 while the refined petroleum or kerosene sells at from fifteen to twenty cents4 ,as great competition exists among the refiners1 there is a strong inducement to turn the heavier portions of the naphtha into the kerosene tank1 so as to get for it the price of kerosene4 ,in this way the inflammable naphtha or benzine is sometimes mixed with the kerosene1 rendering the whole highly dangerous4 ,dr4 ,d4 ,b4 ,white1 ,president of the ,board of ,health of ,new ,orleans1 found that experimenting on oil which flashed at #aac degrees ,fahrenheit1 an addition of one per cent4 of naphtha caused it to flash at #ajc degrees2 two per cent4 brought the flashing point down to #ib degrees1 five per cent4 to #hc degrees1 ten per cent4 to #ei degrees1 and twenty per cent4 of naphtha added brought the flashing point down to #dj degrees ,fahrenheit4 ,after the addition of twenty per cent4 of naphtha the oil burned at #ej degrees ,fahrenheit4 ,there are two distinct tests for oil1 the flashing test and the burning test4 ,the flashing test determines the flashing point of the oil1 or the lowest temperature at which it gives off an inflammable vapor4 ,this is the most important test1 as it is the inflammable vapor1 evolved at atmospheric temperatures1 that causes most accidents4 ,moreover1 an oil which has a high flashing test is sure to have a high burning test1 while the reverse is not true4 ,the burning test fixes the burning point of the oil1 or the lowest temperature at which it takes fire4 ,the burning point of an oil is from ten to fifty degrees ,fahrenheit higher than the flashing point4 ,the two points are quite independent of each other2 the flashing point depends upon the amount of the most volatile constituents present1 such as naphtha1 etc41 while the burning point depends upon the general character of the whole oil4 ,one per cent4 of naphtha will lower the flashing point of an oil ten degrees without materially affecting the burning test4 ,the burning test does not determine the real safety of the oil1 that is1 the absence of naphtha4 ,the flashing test should1 therefore1 be the only test1 and the higher the flashing point the safer the oil4 ,in regard to the danger of using the lighter petroleum oils1 the following1 under the head of ,naphtha and ,benzine under ,false ,names1 is taken from ,prof4 ,c4 ,f4 ,chandler's article on ,petroleum in ,johnson's ,cyclopedia4 ,he says3 ,processes have been patented1 and venders have sold rights throughout the country1 for patented and secret processes for rendering gasoline1 naphtha1 and benzine non-explosive4 ,thus treated1 these explosive oils1 just as explosive as before the treatment1 are sold throughout the country under trade names4 ,these processes are not only totally ineffective1 but they are ridiculous4 ,roots1 gums1 barks1 and salts are turned indiscriminately into the benzine1 to leave it just as explosive as before4 ,no wonder we have kerosene accidents1 with agents scattered through the country selling county rights and teaching retail dealers how to make these murderous 'non-explosive' oils4 ,the experiments these venders make to deceive their dupes are very convincing4 ,none of the petroleum products are explosive per se1 nor are their vapors explosive under all circumstances when mixed with air4 ,a certain ratio of air to vapor is necessary to make an explosive mixture4 ,equal volumes of vapor and air will not explode2 three parts of air and one of vapor gives a vigorous puff when ignited in a vessel2 five volumes of air to one of vapor gives a loud report4 ,the maximum degree of violence results from the explosion of eight or nine parts of air mixed with vapor4 ,it requires considerable skill to make at will an explosive mixture with air and naphtha1 and it is consequently very easy for the vender not to make one4 ,in most cases the proportion of vapor is too great1 and on bringing a flame in contact with the mixture it burns quietly4 ,the vender1 to make his oil appear non-explosive1 unscrews the wick-tube and applies a match1 when the vapor in the lamp quietly takes fire and burns without explosion4 ,or he pours some of the 'safety oil' into a saucer and lights it4 ,there is no explosion1 and ignorant persons1 biased by the saving of a few cents per gallon1 purchase the most dangerous oils in the market4 ,it is not possible to make gasoline1 naphtha1 or benzine safe by any addition that can be made to it4 ,nor is any oil safe that can be set on fire at the ordinary temperature of the air4 ,nothing but the most stringent laws1 making it a ,state prison offense to mix naphtha and illuminating oil1 or to sell any product of petroleum as an illuminating oil or fluid to be used in lamps1 or to be burned1 except in air gas machines1 that will evolve an inflammable vapor below #ajj degrees1 or better1 #abj degrees ,fahrenheit1 will be effectual in remedying the evil4 ,in case of an accident from the sale of oil below the standard1 the seller should be compelled to pay all damages to property1 and1 if a life is sacrificed1 should be punished for manslaughter4 ,it should be made extremely hazardous to sell such oils4 ,prof ,chandler is professor of analytical chemistry1 ,school of ,mines1 ,columbia ,college4 ,there is no substance on earth1 or under the earth1 which will chemically combine with naphtha1 or that will destroy its peculiar volatile and explosive properties4 ,the manufacturers of petroleum products have exhausted the whole resources of chemistry to make this product available as a safe burning oil1 and their inability to do so proclaims the fact that it cannot be done4 ,chemistry has shown that naphtha1 and1 in fact1 the other products of petroleum1 will not part with their hydrogen or change the nature of their compounds1 except by decomposition from a union with oxygen1 that is1 by combustion4 ,these humbugs1 who deceive people for their own gains1 may put camphor1 salt1 alum1 potatoes1 etc41 into naphtha1 and call it by whatever fancy name they please4 ,the camphor is dissolved1 the salt partially2 potatoes have no effect whatever4 ,the camphor may disguise the smell of the naphtha1 and sometimes myrhane or burnt almonds may be used for the same purpose4 ,but1 no matter what is used1 the liability to explosion is not lessened in any degree4 ,the stuff is always dangerous and always will be4 ,there is not much danger in the use of kerosene1 if it is of the standard required by law in several of the ,states4 ,at the same time petroleum is dangerous under certain conditions4 ,where oil is heated it is more or less inflammable1 and1 in fact1 inflammability is only a question of temperature of the oil1 after all4 ,burning oils should be kept in a moderately cool place1 and always with care4 ,of course1 if a lighted lamp is dropped and broken1 the oil is liable to take fire1 though the lamp may be put out in the fall1 or the light drowned by the oil1 or the oil not take fire at all4 ,this will be the effect if the oil is cool and of high flash test4 ,when a lamp is lighted1 and remains burning for some time1 it should never be turned down and set aside4 ,the theory is1 that while lighting1 a certain supply of gas is created from the oil1 and that when the wick is turned down that supply still continues to flow out1 and not being consumed1 forms an inflammable gas in the chimney1 which will explode when a sufficient quantity of air is mixed with it in the presence of light1 which may happen if a person blows down the chimney2 but a lamp should never be extinguished in that way4 ,a good1 high test kerosene oil can be made with ordinary care as safe as sperm oil1 though1 of course1 it is not so safe as a matter of fact4 ,we are sure to hear of it when an accident happens1 but we never hear of the reckless use of kerosene where an accident does not occur1 and yet there are few things so generally carelessly handled as burning oils4--,fireman's ,journal 99 99 99 99 99 ,,composition ,,of ,,the ,,petroleum ,,of ,,the ,,caucasus4 ,by ,,mm4 ,p ,,schutzenberger and ,n4 ,,tonine4 ,all portions of this petroleum contain saturated carbides of the formula ,cn,h#bn1 which the authors name paraffenes4 ,at a bright red heat they yield benzinic carbides1 ,cn,h#bn-#f1 naphthalin and a little anthracen4 ,at dull redness the products are along with unaltered paraffenes1 products which unite energetically with bromine1 and which are converted into resinous polymers of ordinary sulphuric acid4 ,it is difficult to isolate1 by means of fractional distillation1 definite products with constant boiling points4 99 99 99 99 99 ,,notes ,,on ,,cananga ,,oil ,,or ,,ilang-,,ilang ,,oil4 ,footnote3 ,from the ,archiv der ,pharmacie4 ,by ,f4 ,a4 ,,fl,,ckiger4 ,this oil1 on account of its fragrance1 which is described by most observers as extremely pleasant1 has attained to some importance1 so that it appears to me not superfluous to submit the following remarks upon it and the plant from which it is derived4 ,the tree1 of which the flowers yield the oil known under the name ,ilang-ilang or ,alanguilan1 is the ,cananga odorata1 ,hook4 fil4 et ,thomp41#a of the order ,unonace1 for which reason it is called also in many price lists ,oleum ,anon1 or ,oleum ,unon ,it is not known to me whether the tree can be identified in the old ,indian and ,chinese literature4#b ,in the west it was first named by ,ray as ,arbor ,saguisan1 the name by which it was called at that time at ,luon#c ,rump#d gave a detailed description of the ,bonga ,cananga1 as the ,malays designate the tree 7,tsjampa among the ,javanese72 ,rumph's figure1 however is defective4 ,further1 ,lamarck#e has short notices of it under ,canang odorant1 ,uvaria odorata4 ,according to ,roxburgh1#f the plant was in #agig brought from ,sumatra to the ,botanical ,gardens in ,calcutta4 ,dunal devoted to the ,ucaria odorata1 or1 properly1 ,unona odorata1 as he himself corrected it1 a somewhat more thorough description in his ,monographic de la ,famille des ,anonacees1#g which principally repeats ,rumph's statements4 ,footnote #a3 ,flora ,indica1 i 7#ahee71 #acj4 ,footnote #b3 ,no mention of any plant or flowers1 which might be identified with ,cananga1 can be traced in any ,sanskrit works4--,dr4 ,charles ,rice1 ,new ,remedies1 ,april1 #ahha1 page #ih4 ,footnote #c3 ,ray4 ,historia ,plantarum1 ,supplementum1 tomi i et ii ,hist4 ,stirpium ,insul ,luzonensis et ,philippinarum a ,georgio ,josepho ,canello2 ,london1 #agjd1 #hc ,footnote #d3 ,herbarium ,amboinense1 ,amboinsch ,kruidboek1 ii4 7,amsterdam1 #agej71 cap4 xix1 fol4 #aie and tab4 #fe4 ,footnote #e3 ,encyclopdie mthodique4 ,botanique1 i 7#aghc71 #eie4 ,footnote #f3 ,flora ,indica1 ii4 7,serampore1 #ahcb71 #ffa4 ,footnote #g3 ,paris1 #ahag1 p4 #ajh1 #aje4 ,lastly1 we owe a very handsome figure of the ,cananga odorata to the magnificent ,flora ,jav1 of ,blume2#a a copy of this1 which in the original is beautifully colored1 is appended to the present notice4 ,that this figure is correct ,i venture to assume after having seen numerous specimens in ,geneva1 with ,de ,candolle1 as well as in the ,delessert herbarium4 ,the unjustifiable name ,unona odoratissima1 which incorrectly enough has passed into many writings1 originated with ,blanco1#b who in his description of the powerful fragrance of the flowers1 which in a closed sleeping room produces headache1 was induced to use the superlative odoratissima4 ,baillon#c designated as ,canangium the section of the genus ,uvaria1 from which he would not separate the ,ilang-ilang tree4 ,footnote #a3 ,vol4 i4 7,brussels1 #ahbi71 fol4 #bi1 tab ix et xiv4 ,b4 ,footnote #b3 ,flora de ,filipinas1 ,manila1 #ahde1 #cbe4 ,unona odoratissima1 ,alang-ilan4 ,the latter name1 according to ,sonnerat1 is stated by the ,lamarck to be of ,chinese origin2 ,herr ,reymann derives it from the ,tagal language4 ,footnote #c3 ,dictionnaire de ,botanique4 ,illustration3 ,,canaga ,,odorata ,the notice of ,maximowicz1#a ,ueber den ,ursprung des ,parfums ,ylang-,ylang1 contains only a confirmation of the derivation of the perfume from ,cananga4 ,footnote #a3 ,just's ,botanischer ,jahresbericht1 #ahge1 #igc4 ,cananga odorata is a tree attaining to a height of #fj feet1 with few but abundantly ramified branches4 ,the shortly petioled long acuminate leaves1 arranged in two rows1 attain a length of #ah centimeters and a breadth of #g centimeters2 the leaf is rather coriaceous1 and slightly downy only along the nerves on the under side4 ,the handsome and imposing looking flowers of the ,cananga odorata occur to the number of four on short peduncles4 ,the lobes of the tripartite leathery calyx are finally bent back4 ,the six lanceolate petals spread out very nearly flat1 and grow to a length of #g centimeters and a breadth of about #ab millimeters2 they are longitudinally veined1 of a greenish color1 and dark brown when dried4 ,the somewhat bell-shaped elegantly drooping flowers impart quite a handsome appearance1 although the floral beauty of other closely allied plants is far more striking4 ,the filaments of the ,cananga are very numerous2 the somewhat elevated receptacle has a shallow depression at the summit4 ,the green berry-like fruit is formed of from fifteen to twenty tolerably long stalked separate carpels which inclose three to eight seeds arranged in two rows4 ,the umbel-like peduncles are situated in the axils of the leaves or spring from the nodes of leafless branches4 ,the flesh of the fruit is sweetish and aromatic4 ,the flowers possess a most exquisite perfume1 frequently compared with hyacinth1 narcissus1 and cloves4 ,cananga odorata1 according to ,hooker and ,thomson or ,bentham and ,hooker1#a is the only species of this genus2 the plants formerly classed together with it under the names ,unona or ,uvaria1 among which some equally possess odorous flowers1 are now distributed between those two genera1 which are tolerably rich in species4 ,from ,uvaria the ,cananga differs in its valvate petals1 and from ,unona in the arrangement of the seeds in two rows4 ,footnote #a3 ,genera ,plantarum1 i1 7#ahfd71 #bd4 ,cananga odorata is distributed throughout all ,southern ,asia1 mostly1 however1 as a cultivated plant4 ,in the primitive forest the tree is much higher1 but the flowers are1 according to ,blume1 almost odorless4 ,in habit the ,cananga resembles the ,michelia champaca1 ,l41#a of the family ,magnoliace1 an ,indian tree extraordinarily prized on account of the very pleasant perfume of its yellow flowers1 and which was already highly celebrated in ancient times in ,india4 ,among the admired fragrant flowers which are the most prized by the in this respect pampered ,javanese1 the ,tjempaka 7,michelia champaca7 and the ,kenangga wangi 7,cananga odorata7#b stand in the first rank4 ,footnote #a3 ,a beautiful figure of this also is given in ,blume's ,flora ,jav1 iii41 ,magnoliace1 tab4 ,i4 ,footnote #b3 ,junghuhn1 ,java1 ,leipsic1 #aheb1 #aff4 ,it is not known to me whether the oil of cananga was prepared in former times4 ,it appears to have first reached ,europe about #ahfd2 in ,paris and ,london its choice perfume found full recognition4#a ,the quantities1 evidently only very small1 that were first imported from the ,indian ,archipelago were followed immediately by somewhat larger consignments from ,manila1 where ,german pharmacists occupied themselves with the distillation of the oil4#b ,footnote #a3 ,jahresbericht d4 ,pharmacie1 by ,wiggers and ,husemann1 #ahfg1 #dbb4 ,footnote #b3 ,jahresbericht1 #ahfh1 #aff4 ,oscar ,reymann and ,adolf ,ronsch1 of ,manila1 exhibited the ilang-ilang oil in ,paris in #ahgh2 the former also showed the ,cananga flowers4 ,the oil of the flowers of the before-mentioned ,michelia champaca1 which stood next to it1 competes with the cananga oil1 or ilang-ilang oil1 in respect to fragrance4#a ,how far the latter has found acceptance is difficult to determine2 a lowering of the price which it has undergone indicates probably a somewhat larger demand4 ,at present it may be obtained in ,germany for about #fjj marks 7#cj7 the kilogramme4#b ,since the ,cananga tree can be so very easily cultivated in all warm countries1 and probably everywhere bears flowers endowed with the same pleasant perfume1 it must be possible for the oil to be produced far more cheaply1 notwithstanding that the yield is always small4#c ,it may be questioned whether the tree might not1 for instance1 succeed in ,algeria1 where already so many exotic perfumery plants are found4 ,footnote #a3 ,archiv der ,pharmacie1 ccxiv4 7#ahgi71 #ah4 ,footnote #b3 ,according to information kindly supplied by ,herr ,reymann1 in ,paris1 ,nice1 and ,grasse1 annually about #bjj kilogrammes are used2 in ,london about #ej kilogrammes1 and equally as much in ,germany 7,leipsic1 ,berlin1 ,frankfort74 ,footnote #c3 #be grammes of oil from #e kilogrammes of flowers1 according to ,reymann4 ,according to ,guibourt1#a the macassar oil1 much prized in ,europe for at least some decades as a hair oil1 is a cocoa nut oil digested with the flowers of ,cananga odorata and ,michelia champaca1 and colored yellow by means of turmeric4 ,in ,india unguents of this kind have always been in use4 ,footnote #a3 ,histoire ,naturelle des ,drogues ,simples1 iii4 7#ahej71 #fge4 ,the name ,cananga is met with in ,germany as occurring in former times4 ,an ,oleum destillatum ,canang is mentioned by the ,leipsic apothecary1 ,joh4 ,heinr4 ,linck#a among some new exotics in the ,sammlung von ,naturund ,medicin- wie1 auch hierzu gehorigen ,kunst- und ,literatur ,geschichten1 so sich ,anno #agai in ,schlesien und andern ,lndern begeben 7,leipsic und ,budissin1 #agai74 ,as1 however1 the fruit of the same tree sent together with this cananga oil is described by ,linck as uncommonly bitter1 he cannot probably here refer to the present ,cananga odorata1 the fruit-pulp of which is expressly described by ,humph and by ,blume as sweetish4 ,further an ,oleum ,canang1 ,camel-straw oil1 occurs in #agfe in the tax of ,bremen and ,verden4#b ,it may remain undetermined whether this oil actually came from camel-straw1 the beautiful grass ,andropogon laniger4 ,footnote #a3 ,compare ,flckiger1 ,pharmakognosic1 #b;d edit1 #ahha1 p4 #aeb4 ,footnote #b3 ,flckiger1 ,documente zur ,geschichte der ,pharmacie1 ,halle 7#ahgf71 p #ic4 ,from a chemical point of view cananga oil has become interesting because of the information given by ,gal1#a that it contains benzoic acid1 no doubt in the form of a compound ether4 ,so far as ,i1 at the moment1 remember the literature of the essential oils1 this occurrence of benzoic acid in plants stands alone1#b although in itself it is not surprising1 and probably the same compound will yet be frequently detected in the vegetable kingdom4 ,as it was convenient to test the above statement by an examination ,i induced ,herr ,adolf ,convert1 a pharmaceutical student from ,frankfort-,on-,main1 to undertake an investigation of ilang-ilang oil in that direction4 ,the oil did not change litmus paper moistened with alcohol4 ,a small portion distilled at #agj ,c42 but the thermometer rose gradually to #bij1 and at a still higher temperature decomposition commenced4 ,that the portions passing over below #bij had a strong acid reaction already indicated the presence of ethers4 ,herr ,convert boiled #aj grammes of the oil with #bj grammes of alcohol and #a gramme of potash during one day in a retort provided with a return condenser4 ,finally the alcohol was separated by distillation1 the residue supersaturated with dilute sulphuric acid1 and together with much water submitted to distillation until the distillate had scarcely an acid reaction4 ,the liquid that had passed over was neutralized with barium carbonate1 and the filtrate concentrated1 when it yielded crystals1 which were recognized as nearly pure acetate4 ,the acid residue1 which contained the potassium sulphate1 was shaken with ether2 after the evaporation of the ether there remained a crystalline mass having an acid reaction which was colored violet with ferric chloride4 ,this reaction1 which probably may be ascribed to the account of a phenol1 was absent after the recrystallization of the crystalline mass from boiling water4 ,the aqueous solution of the purified crystalline scales then gave with ferric chloride only a small flesh-colored precipitate4 ,the crystals melted at #abj ,c4 ,in order to demonstrate the presence of benzoic acid ,herr ,convert boiled the crystals with water and silver oxide and dried the scales that separated from the cooling filtrate over sulphuric acid4 #j4jcab gramme gave upon combustion #j4jadg gramme of silver1 or #dg4a per cent4 ,the benzoate of silver contains #df4f per cent1 of metal2 the crystals prepared from the acid of ilang-ilang oil were1 therefore1 benzoate of silver4 ,for the separation of the alcoholic constituent1 which is present in the form of an apparently not very considerable quantity of benzoic ether1 far more ilang-ilang oil would be required than was at command4 ,footnote #a3 ,comptes ,rendus1 lxxvi4 7#ahgc71 #adbh1 and abstracted in the ,pharmaceutical ,journal #c1 iv41 p4 #bh2 also in ,jahresbericht1 #ahgc1 p4 #dca4 ,footnote #b3 ,overlooking ,peru balsam and ,tolu balsam4 ,besides the benzoic ether and1 probably1 a phenol1 mentioned above1 there may be recognized in ilang-ilang oil an aldehyde or ketone1 inasmuch as upon shaking it with bisulphite of sodium ,i observed the formation of a very small quantity of crystals4 ,that ,gal did not obtain the like result must at present remain unexplained4 ,like the benzoic acid the acetic acid is1 no doubt1 present in cananga oil in the form of ether4 99 99 99 99 99 ,,chian ,,turpentine4 ,the following letter has been received by the editors of the ,repertoire de ,pharmacie3 ,for some months past1 a good deal has been heard about a product of our island that had quite fallen into disuse1 and which no one cared to gather1 so much had the demand fallen off because a substitute for it had been found in ,europe2 ,i mean ,chian turpentine4 ,as this product is destined to take a certain part in the treatment of cancer1 according to some ,english physicians1 permit me1 sir1 to give your readers a few interesting details1 obtained on the spot1 concerning the turpentine tree and its product4 ,the turpentine tree 7,pistacia terebinthus ,l47 has existed in our island for many centuries1 judging from the enormous dimensions of some of these trees1 compared1 too1 with their slow rate of growth4 ,the trunks of some measure from #d to #e meters in circumference1 and their heights vary from #ae to #bj meters4 ,on my own land there is an enormous tree1 by far the largest on the island1 the circumference of its trunk being #f meters4 ,many of these great trees have been used in the construction of mills1 presses1 etc41 on account of the hardness of their wood4 ,it is in the vicinity of the town and in three or four neighboring villages that these trees are found4 ,to-day1 at a careful estimate1 there may be #a1ejj trees capable of yielding #b1jjj kilos of turpentine1 mixed with at least #cj per cent of foreign matter4 ,there are no appliances for refining the product here1 except the sieves through which it is passed to remove the pebbles and bits of wood which are found in it4 ,it is gathered from incisions made in the tree in ,june4 ,axes are used for this purpose1 and the incision must be through the whole thickness of the bark4 ,through these outlets the turpentine falls to the foot of the tree1 and mixes with the earth there4 ,on its first appearance the turpentine is of a sirupy consistence1 and is quite transparent2 gradually it becomes more opaque1 and of a yellowish-white color4 ,it is at this period also that it gives off its characteristic odor most abundantly4 ,it is1 however1 not the product turpentine that is most esteemed by the natives1 but the fruit of the tree1 a kind of drupe disposed in clusters4 ,the fruit is improved by the incisions made in the tree for the escape of the turpentine1 otherwise the resin1 having no other outlet1 would impregnate the former1 hinder its complete development1 and render it useless for the purposes for which it is cultivated4 ,one circumstance worth noting is that1 as soon as the fruit commences to ripen1 the flow of turpentine completely ceases4 ,this is toward ,august2 the fruit is then green2 it is gathered1 dried in the sun1 bruised1 and a fine yellowish-green oil is drawn from it1 which is soluble in ether4 ,this oil is used for alimentary purposes1 but rarely for illumination since the introduction of petroleum4 ,it is mostly used in making sweet cakes1 and often as a substitute for butter1 in all cases where the latter is employed4 ,i use it daily myself without perceiving any difference4 ,i may here be permitted to correct a slight mistake that has crept into several standard botanical works4 ,it is therein stated that the inhabitants of this country extract from the fruit of the lentisc 7,pistacia lentiscus ,l41 a well-known shrub growing on this island1 from which ,chian mastic is obtained71 an alimentary and illuminating oil4 ,this fruit has never been gathered for its oil within the memory of man4 ,the lentisc has probably been thus mistaken for the turpentine tree4 ,for the last twenty years the gathering of turpentine has been almost abandoned1 although the incisions in the trees have been regularly made1 but the value was so small that proprietors did not care to collect it1 and left it to run to waste4 ,there were but a few pharmacists of ,smyrna and the neighboring islands who took a small quantity for making medicinal plasters4 ,an utterly insignificant quantity found its way into ,europe4 ,how is it then that1 after so many years1 it was found in ,europe8 ,the problem is easily explained--the greater part came from ,venice4 ,this is indubitable1 and1 lately1 an ,english chemist1 ,mr4 ,w4 ,martindale1 in a communication to the ,chemical ,society of ,london1 expressed doubts as to the authenticity of the turpentine used in the treatment of cancer4 ,if turpentine can really somewhat relieve this disease1 and if this treatment is generally accepted in ,europe1 ,i much fear you will only obtain substitutions of very inferior quality to the turpentine produced in our island4 ,this year the ,chians have been surprised by an extensive demand for this product1 from ,london in the first place1 and secondly from ,vienna1 and the proprietors1 although but poorly provided at the moment1 sent away nearly #fjj kilos ,paris has not yet made any demand4 ,yours1 etc41 ,,dr4 ,,stiepowich4 ,chio1 ,turkey4 99 99 99 99 99 ,,on ,,the ,,change ,,of ,,volume ,,which ,,accompanies ,,the ,,galvanic ,,deposition ,,of ,a ,,metal4 ,by ,m4 ,e4 ,,bouty4 ,in previous notes ,i have established1 first1 that the galvanic depositions experience a change of volume1 from which there results a pressure exercised on the mould which receives them2 second1 that the ,peltier phenomenon is produced at the surface of contact of an electrode and of an electrolyte4 ,fresh observations have caused me to believe that the two phenomena are connected1 and that the first is a consequence of the second4 ,the ,peltier effect can clearly be proved when the electrolysis is not interfered with by energetic secondary actions1 and particularly with the sulphate and nitrate of copper1 the sulphate and chloride of zinc1 and the sulphate and chloride of cadmium4 ,for any one of these salts it is possible to determine a value1 ,i1 of the intensity of the current which produces the metallic deposit such that1 for all the higher intensities the electrode becomes heated1 and such that it becomes cold for less intensities4 ,i will designate this intensity1 ,i1 under the name of neutral point of temperatures4 ,the new fact which ,i have observed is1 that in the electrolysis of the same salts it is always possible to lower the intensity of the current below a limit1 ,i'1 such that the compression produced by the deposit changes its direction1 that is to say1 instead of contracting the metal dilates in solidifying4 ,this change1 although unquestionable1 is sufficiently difficult to produce with sulphate of copper4 ,it is necessary to employ as a negative electrode a thermometer sensitive to #a_/bjj of a degree1 and to take most careful precautions to avoid accidental deformations of the deposit2 but the phenomenon can be observed very easily with nitrate of copper1 the sulphate of zinc1 and the chloride of cadmium4 ,there is1 therefore1 a neutral point of compression in the same cases where there is a neutral point of temperatures4 ,with the salts of iron1 nickel1 etc41 for which the neutral point of temperatures cannot be arrived at1 there is also no neutral point of compression2 and the negative electrode always becomes heated1 and the deposit obtained is always a compressing deposit4 ,i have determined1 by the help of observations made with ten different current strengths1 the constants of the formul which ,i have explained elsewhere1 and which gives the apparent excess1 y1 of the thermometer electrode compressed by the metallic deposit in terms of the time1 t1 during which the metal was depositing3 ,a t 7#a7 y ------- ,b t ,the constant1 ,a1 is proportional to the variation of volume of the unit of volume of the metal4 ,the values of ,a1 without being exactly regular1 are sufficiently well represented within practical limits by the formula3 7#b7 ,a - a'i b'i1 of the same form as the expression ,e3 ,e - ai bi1 of the heating of the thermometer electrode4 ,further1 every cause which affects the coefficients1 a or b1 also affects in the same way a' and b'3 such causes being the greater or less dilution of the solution1 the nature of the salt1 etc4 ,it is1 therefore1 impossible not to be struck by the direct relation of the thermic and mechanical phenomena of which the negative electrode is the origin4 ,the following is the explanation which ,i offer3 ,the thermometer indicates the mean temperature of the liquid just outside it2 this temperature is not necessarily that of the metal which incloses it4 ,the current1 propagated almost exclusively by the molecules of the decomposed salt1 does not act directly to cause a variation in the temperature of the dissolving molecules2 these change heat with the molecules of the electrolyte1 which should be in general hotter than those when a heating is noticed and colder when a cooling is observed4 ,suppose it is found1 in the first case1 that the metal1 at the moment when it is deposited1 is hotter than the liquid1 and1 consequently1 than the thermometer2 it becomes colder immediately after the deposit1 and consequently contracts2 the deposit is compressed4 ,the reverse is the case when the metal is colder than the liquid2 the deposit then dilates4 ,if this hypothesis is correct1 the excess1 ,t1 of the temperature of the metal over the liquid which surrounds the thermometer should be proportional to the contraction1 ,a1 represented by the formula 7#b71 and the neutral point1 ,i'1 of the contraction corresponds to the case where the temperature of the metal is precisely equal to that of the liquid4 ,it might be expected1 perhaps1 from the foregoing1 that ,i' ,i2 this would take place if the excess of temperature of the metal1 measured by the contraction1 were rigorously proportional to the heating of the liquid1 for then the two quantities would be null at the same time4 ,careful experiment proves that this is not the case4 ,the sulphate of copper gives compressing deposits on a thermometer which is undoubtedly cooling2 chloride of zinc of a density #bjj can give expanding deposits on a thermometer which is heating4 ,there is1 therefore1 no proportionality2 but it must be remarked that the temperature of the metal which is deposited does not depend only on the quantities of heat disengaged in an interval of molecular thickness which is infinitely small compared with the thickness of the layer1 of which the variations of temperature are registered by the thermometer4 ,there is nothing surprising1 therefore1 that the two variations of temperature1 according exactly with one another1 do not follow identically the same laws4--,comptes ,rendus4 99 99 99 99 99 ,,analyses ,,of ,,rice ,,soils ,,from ,,burmah4 ,by ,r4 ,,romanis1 ,d4,sc41 ,chemical ,examiner1 ,british ,burmah4 ,the analyses of rice soils was undertaken at the instance of the ,revenue ,settlement ,survey1 who wanted to know if the chemical composition of the soil corresponded in any way to the valuation as fixed from other evidence4 ,it was found that the amount of phosphoric acid in the soil in any one district corresponded pretty well with the ,settlement ,officers' valuation1 but on comparing two districts it was found that the district which was poorer in phosphoric acid gave crops equal to the richer one4 ,on inquiry it was found that in the former the rice is grown in nurseries and then planted out by hand1 whereas in the latter1 where the holdings are much larger1 the grain is sown broadcast4 ,the practice of planting out the young crops enables the cultivator to get a harvest #bj per cent4 better than he would otherwise do1 and hence the poorer land equals the richer4 ,the deductions drawn from this investigation are1 first1 that1 climate and situation being equal1 the value of soil depends on the phosphoric acid in it2 and1 second1 that the planting-out system is far superior to the broadcast system of cultivation for rice4 ,results of two analyses of soils from ,syriam1 near ,rangoon1 are appended3 ,soluble in ,hydrochloric ,acid4 ,i4 ,,ii4 ,virgin ,soil4 ,organic matter #d4eij #h4e8h ,oxide of iron and alumina #h4ici #g4agi ,magnesia #j4dfi #j4fgg ,lime trace4 #j4aca ,potash #j4ach #j4ahg ,soda #j4acf #j4ccg ,phosphoric acid #j4ajj #j4ajh ,sulphuric acid #j4jbe #j4aag ,silica ---- #j4jje -------- --------- #ad4cig #ag4bdi ,soluble in ,sulphuric ,acid4 ,alumina #ag4dfj #ae4fhd ,magnesia #j4dei #j4ddf ,lime #j4bhf trace4 ,potash #j4faf #a4bej ,soda #j4cag #j4bhe --------- --------- #ai4ach #ag4ffe ,residue4 ,silica1 soluble #aa4fge #fi4edf insoluble #di4dgg _/ ,alumina #c4jfb #d4agh ,lime #j4gjj #j4acd ,magnesia #j4bab trace4 ,potash #j4bgf #a4ahj ,soda #j4ejc #a4jdh -------- --------- #ajj4jjj #ajj4jjj ,these are alluvial soils from the ,delta of the ,irrawaddy4 99 99 99 99 99 ,,dry ,,air ,,refrigerating ,,machine4 ,a large number of scientific and other gentlemen interested in mechanical refrigeration lately visited the works of ,messrs4 ,j4 ,e4 ,hall1 of ,dartford1 to inspect the working of one of their improved horizontal dry air refrigerators6 ,the machine1 which is illustrated below1 is designed to deliver about #aj1jjj cubic feet of cold air per hour1 when running at the rate of #ajj revolutions per minute1 and is capable of reducing the temperature of the air from #ij deg4 above1 to about #ej deg4 below zero1 ,fah41 with an initial temperature of cooling water of #ij deg4 to #ie deg4 ,fah4 ,it can1 however1 be run at as high a speed as #adj revolutions per minute4 ,the air is compressed in a water-jacketed1 double-acting compression cylinder1 to about #ee lb4 per square inch --more or less according to the temperature of the cooling water--the inlet valve being worked from a cam on the crank shaft1 to insure a full cylinder of air at each stroke1 and the outlet valves being self acting1 specially constructed to avoid noise in working and breakages1 which have given rise to so much annoyance in other cold air machines4 ,the compressed air1 still at a high temperature1 is then passed through a series of tubular coolers1 where it parts with a great deal of its heat1 and is reduced to within #d deg4 or #e deg4 of the initial temperature of the cooling water4 ,here also a considerable portion of the moisture1 which1 when fresh air is being used1 must of necessity enter the compression cylinder1 is condensed and deposited as water4 ,illustration3 ,,compression ,,cylinder4 ,,scale #a_/fj ,after being cooled1 the compressed air is then admitted to the expansion cylinder1 but as it still contains a large quantity of water in solution1 which1 if expansion was carried immediately to atmospheric pressure1 would1 from the extreme cold1 be converted into snow and ice1 with a positive certainty of causing great trouble in the valves and passages4 ,it is got rid of by a process invented by ,mr4 ,lightfoot1 which is at the same time extremely simple and beautiful in action1 and efficient4 ,instead of reducing the compressed air at once to atmospheric pressure1 it is at first only partially expanded to such an extent that the temperature is lowered to about #ce deg4 to #dj deg4 ,fah41 with the result that very nearly the whole of the contained aqueous vapor is condensed into water4 ,the partially expanded air which now contains the water as a thick mist is then admitted into a vessel containing a number of grids1 through which it passes1 parting all the while with its moisture1 which gradually collects at the bottom and is blown off4 ,the surface area of the grids is so arranged that by the time the air has passed through them it is quite free from moisture1 with the exception of the very trifling amount which it can hold in solution at about #ce deg4 ,fah41 and #cj lb4 pressure4 ,the expansion is then continued to atmospheric pressure and the cooled air containing only a trace of snow is then discharged ready for use into a meat chamber or elsewhere4 ,in small machines the double expansion is carried out in one cylinder containing a piston with a trunk1 the annulus forming the first expansion and the whole piston area the second1 but in larger machines two cylinders of different sizes are used1 just as in an ordinary compound engine4 ,to compensate for the varying temperature of the cooling water the cut-off valve to the first or primary expansion is made adjustable2 and this can either be regulated as occasion requires by hand1 or else automatically4 ,the temperature in the depositors being kept constant under all variations in cooling water1 there is the same abstraction of moisture in the tropics as in colder climates1 and the cold air finally discharged from the machine is also kept at a uniform temperature4 ,illustration3 ,expansion ,cylinder4 ,scale #a_/fj4ib ,f4 temperature of entering air4 ,cooling water entering in at #hf ,f4 ,illustration3 ,expansion ,cylinder4 ,scale #a_/fj4 #fh ,f4 temperature of entering air4 ,cooling water entering in at #fe ,f4 #abe revs4 per minute1 or #cab ft4 per minute per piston speed4 ,the diagrams are reduced from the originals1 taken from the compression cylinder when running at the speed of #abe revolutions per minute1 and also from the expansion cylinder1 the first when the cooling water was entering the coolers at #hf deg4 ,fah41 and the latter when this temperature was reduced to #fe deg4 ,fah4 ,in all cases the compressed air is cooled down to within from #c deg4 to #e deg4 of the initial temperature of the cooling water1 thus showing the great efficiency of the cooling apparatus4 ,the machine has been run experimentally at ,dartford1 under conditions perhaps more trying than can possibly occur1 even in the tropics1 the air entering the compression cylinder being artificially heated up to #he deg4 and being supersaturated at that temperature by a jet of steam laid on for the purpose4 ,in this case no more snow was formed than when dealing with aircontaining a very much less proportion of moisture4 ,the vapor was condensed previous to final expansion and abstracted as water in the drying apparatus4 ,the machine was exhibited at work in connection with a cold chamber which was kept at a temperature of about #aj deg4 ,fah41 besides which several hundredweight of ice were made in the few days during which the experiments lasted4 ,this machine is in all respects an improvement on the machine which we have already illustrated4 ,in that machine ,messrs4 ,hall were trammeled by being compelled to work to the plans of others4 ,in the present case the machine has been designed by ,mr4 ,lightfoot1 and appears to leave little to be desired4 ,it is a new thing that a cold air machine may be run at any speed from #cb to #abj revolutions per minute4 ,in its action it is perfectly steady1 and the cold air chamber is kept entirely clear of snow4 ,the dimensions of the machine are also eminently favorable to its use on board ship4-,the ,engineer4 ,illustration3 ,,dry ,,air ,,refrigerating ,,machine 99 99 99 99 99 ,,thomas',s ,,improved ,,steam ,,wheel4 ,the rotary or steam wheel1 the invention of ,j4,e4 ,thomas1 of ,carlinville1 ,ill41 shown in the annexed figure1 consists of a wheel with an iron rim inclosed within a casing or jacket from which nothing protrudes except the axle which carries the driving pulley1 and the grooved distributing disk4 ,within this jacket1 which need not necessarily be steam-tight1 there is a movable piece1 ,k1 which1 pressing against the rim1 renders steam-tight the channel in which the pistons move when driven by the steam4 ,at the extremities of this channel there are plates which are kept pressed against the wheel by means of spiral springs1 thus rendering the channel perfectly tight4 ,the steam enters the closed space 7which forms one-fourth of the circumference7 through the slide-valve1 ,s1 presses against the pistons1 d1 and causes the wheel to revolve in the direction of the arrows4 ,the slide-valve is closed by the action of the external distributing mechanism1 the piston passes beyond the steam-outlet1 ,a1 and a new piston then comes in play4 ,altogether1 there are six of these pistons1 each one working in an aperture in the rim1 and kept pressed outwardly by means of a spiral spring4 ,the steam acts constantly on the same lever arm and meets with no counter-pressure4 ,the other defects1 likewise1 of the ordinary steam engines in use are obviated to such an extent that the effective power of the steam-wheel is #ej per cent1 greater than that of other and more complicated machines--at least this is the experience of the inventor4 ,illustration3 ,,improved ,,steam-,,wheel4 ,to the inner ends of the pistons there are attached rods which pass through the rim of the wheel 7where they are provided with stuffing-boxes7 and abut against spiral springs4 ,these rods are1 in addition1 connected with levers1 h1 which are pivoted on the spokes of the wheel1 and whose other extremities carry rods1 #b4 ,these latter run through guides on the external face of the rim of the wheel and engage by means of friction-rollers1 in an undulating groove formed in the inner surface of the jacket4 ,when a piston arrives in front of the upper extremity of the steam channel1 the friction roller at that moment enters one of the depressions in the groove1 and thus lifts up the piston and allows it to pass freely beyond the plate which closes the channel4 99 99 99 99 99 ,,the ,,american ,,society ,,of ,,civil ,,engineers4 ,,address ,,of ,,the ,,president1 ,,james ,,bicheno ,,francis1 ,,at ,,the ,,thirteenth ,,annual ,,convention ,,of ,,the ,,society ,,at ,,montreal1 ,,june #ae1 #ahha4 ,you have assembled in convention for the first time outside the limits of the ,united ,states1 and ,i congratulate you on the selection of this beautiful city1 in which and its immediate neighborhood there are so many interesting engineering works1 constructed with the skill and solidity characteristic of the ,british school of engineering4 ,nine of our members are ,canadian engineers1 which must be the excuse of the other members for invading foreign territory4 ,the society was organized ,november #c1 #aheb1 and actively maintained up to ,march #b1 #ahee4 ,eleven only of the present members date from this period4 ,october #b1 #ahfg1 the society was reorganized on a wider basis1 and from that time to the present it has been constantly increasing in interest and usefulness4 ,the membership of the society is now as follows3 ,honorary members44444444 #aa ,corresponding members444 #c ,members44444444444444444 #dia ,associates44444444444444 #ba ,juniors44444444444444444 #eg ,fellows44444444444444444 #ec ---- ,total4444444444444444444 #fcf ,during the last year we have lost six members by death and five by resignation1 and fifty-six new members have been elected and qualified4 ,the most interesting event to the society since the last convention has been the purchase of a house in the ,city of ,new ,york1 as a permanent home1 at a cost of #cj1jjj4 ,this has been accomplished1 so far1 without taxing the resources of the society1 the required payments having been met by subscription4 ,the sum of #aa1ijj had been subscribed to the building fund up to the #beth ult41 by seventy members and twenty-nine friends of the society who are not members4 ,the subscription is still open1 and it is expected that large additions will be made to it by members and their friends to enable the society to make the remaining payments without embarrassment4 ,meetings of the society are held twice in each month during ten months in the year1 for the reading and discussion of papers and other purposes4 ,the new house affords much better accommodations for these purposes than we have ever had before1 and also for the library1 which now contains #h1hej books and pamphlets1 and is constantly increasing4 ,a catalogue of the library is being prepared4 ,part ,i41 embracing railroads and the transactions of scientific societies1 has been printed and furnished to members4 ,,water ,,power4 ,water power in many of the ,states is abundant and contributes largely to their prosperity4 ,its proper development calls for the services of the civil engineer1 and as it is the branch of the profession with which ,i am most familiar1 ,i propose to offer a few remarks on the subject4 ,the earliest applications were to grist and saw mills2 carding and fulling mills soon followed2 these were essential to the comfort of the early settlers who relied on home industries for shelter1 food1 and clothing1 but with the progress of the country came other requirements4 ,the earliest application of water power to general manufacturing purposes appears to have been at ,paterson1 ,new ,jersey1 where ,the ,society for ,establishing ,useful ,manufactures was formed in the year #agia4 ,the ,passaic ,river at this point furnishes1 when at a minimum1 about eleven hundred horse power continuously night and day4 ,the water power at ,lowell1 ,massachusetts1 was begun to be improved for general manufacturing purposes in #ahbb4 ,the ,merrimack ,river at this point has a fall of thirty-five feet1 and furnishes1 at a minimum1 about ten thousand horse power during the usual working hours4 ,at ,cohoes1 in the ,state of ,new ,york1 the ,mohawk ,river has a fall of about one hundred and five feet1 which was brought into use systematically very soon after that at ,lowell1 and could furnish about fourteen thousand horse power during the usual working hours1 but the works are so arranged that part of the power is not available at present4 ,at ,manchester1 ,new ,hampshire1 the present works were commenced in #ahce4 ,the ,merrimack ,river at this point has a fall of about fifty-two feet1 and furnishes1 at a minimum1 about ten thousand horse power during the usual working hours4 ,at ,lawrence1 ,massachusetts1 the ,essex ,co4 built a dam across the ,merrimack ,river1 commencing in #ahde1 and making a fall of about twenty-eight feet1 and a minimum power1 during the usual working hours1 of about ten thousand horse power4 ,at ,holyoke1 ,massachusetts1 the ,hadley ,falls ,co4 commenced their works about #ahde1 for developing the power of the ,connecticut ,river at that point1 where there is a fall of about fifty feet1 and at a minimum1 about seventeen thousand horse power during the usual working hours4 ,at ,lewiston1 ,maine1 the fall in the ,androscoggin ,river is about fifty feet2 its systematic development was commenced about #ahde1 and with the improvement of the large natural reservoirs at the head waters of the river1 now in progress1 it is expected that a minimum power1 during the usual working hours1 of about eleven thousand horse power will be obtained4 ,at ,birmingham1 ,connecticut1 the ,housatonic ,water ,co4 have developed the water power of the ,housatonic ,river by a dam1 giving twenty-two feet fall1 furnishing at a minimum about one thousand horse power during the usual working hours4 ,the ,dundee ,water and ,land ,co41 about #aheh1 developed the power of the ,passaic ,river1 at ,passaic1 ,new ,jersey1 where there is a fall of about twenty-two feet1 giving a minimum power1 during the usual working hours1 of about nine hundred horse power4 ,the ,turners ,falls ,co41 in #ahff1 commenced the development of the power of the ,connecticut ,river at ,turners ,falls1 ,massachusetts1 by building a dam on the middle fall1 which is about thirty-five feet1 and furnishes a minimum power1 during the usual working hours1 of about ten thousand horse power4 ,i have named the above water powers as being developed in a systematic manner from their inception1 and of which ,i have been able to obtain some data4 ,in the usual process of developing a large water power1 a company is formed1 who acquire the title to the property1 embracing the land necessary for the site of the town1 to accommodate the population which is sure to gather around an improved water power4 ,the dam and canals or races are constructed1 and mill sites1 with accompanying rights to the use of the water1 are granted1 usually by perpetual leases subject to annual rents4 ,this method of developing water power is distinctly an ,american idea1 and the only instance where it has been attempted abroad1 that ,i know of1 is at ,bellegarde in ,france1 where there is a fall in the ,rhone of about thirty-three feet4 ,within the last few years works have been constructed for its development1 furnishing a large amount of power1 but from the great outlay incurred in acquiring the titles to the property1 and other difficulties1 it has not been a financial success4 ,the water powers ,i have named are but a small fraction of the whole amount existing in the ,united ,states and the adjoining ,dominion of ,canada4 ,there is ,niagara1 with its two or three millions of horse power2 the ,st4 ,lawrence1 with its succession of falls from ,lake ,ontario to ,montreal2 the ,falls of ,st4 ,antony1 at ,minneapolis2 and many other falls1 with large volumes of water1 on the upper ,mississippi and its branches4 ,it would be a long story to name even the large water powers1 and the smaller ones are almost innumerable4 ,in the ,state of ,maine a survey of the water power has recently been made1 the result1 as stated in the official report1 being between one and two millions of horse power1 part of which will probably not be available4 ,there is an elevated region in the northern part of the ,south ,atlantic ,states1 exceeding in area one hundred thousand square miles1 in which there is a vast amount of water power1 and being near the cotton fields1 with a fine climate1 free from malaria1 its only needs are railways1 capital1 and population1 to become a great manufacturing section4 ,the design and construction of the works for developing a large water power1 together with the necessary arrangements for utilizing it and providing for its subdivision among the parties entitled to it according to their respective rights1 affords an extensive field for civil engineers2 and in view of the vast amount of it yet undeveloped1 but which1 with the increase of population and the constantly increasing demand for mechanical power as a substitute for hand labor1 must come into use1 the field must continue to enlarge for a long time to come4 ,there are many cases in which the power of a waterfall can be made available by means of compressed air more conveniently than by the ordinary motors4 ,the fall may be too small to be utilized by the ordinary motors2 the site where the power is wanted may be too distant from the waterfall2 or it may be desired to distribute the power in small amounts at distant points4#a ,a method of compressing air by means of a fall of water has been devised by ,mr4 ,joseph ,p4 ,frizell1 ,c4,e41 of ,st4 ,paul1 ,minnesota1 which1 from the extreme simplicity of the apparatus1 promises to find useful applications4 ,the principle on which it operates is1 by carrying the air in small bubbles in a current of water down a vertical shaft1 to the depth giving the desired compression1 then through a horizontal passage in which the bubbles rise into a reservoir near the top of this passage1 the water passing on and rising in another vertical or inclined passage1 at the top of which it is discharged1 of course1 at a lower level than it entered the first shaft4 ,footnote #a3 ,journal of the ,franklin ,institute for ,september1 #ahgg4 ,the formation at waterfalls is usually rock1 which would enable the passages and the reservoir for collecting the compressed air to be formed by simple excavations1 with no other apparatus than that required to charge the descending column of water with the bubbles of air1 which can be done by throwing the water into violent commotion at its entrance1 and a pipe and valve for the delivery of the air from the reservoir4 ,the transfer of power by electricity is one of the problems now engaging the attention of electricians1 and it is now done in ,europe in a small way4 ,sir ,william ,thomson stated in evidence before an ,english parliamentary committee1 two years ago1 that he looked forward to the ,falls of ,niagara being extensively used for the production of light and mechanical power over a large area of ,north ,america1 and that a copper wire half an inch in diameter would transmit twenty-one thousand horse power from ,niagara to ,montreal1 ,boston1 ,new ,york1 or ,philadelphia4 ,his statements appear to have been based on theoretical considerations2 but there is no longer any doubt as to the possibility of transferring power in this manner--its practicability for industrial purposes must be determined by trial4 ,dr4 ,paget ,higgs1 a distinguished ,english electrician1 is now experimenting on it in the ,city of ,new ,york4 ,great improvements in reaction water wheels have been made in the ,united ,states within the last forty years4 ,in the year #ahdd1 the late ,uriah ,atherton ,boyden1 a civil engineer of ,massachusetts1 commenced the design and construction of ,fourneyron turbines1 in which he introduced various improvements and a general perfection of form and workmanship1 which enabled a larger percentage of the theoretical power of the water to be utilized than had been previously attained4 ,the great results obtained by ,boyden with water wheels made in his perfect manner1 and1 in some instances1 almost regardless of cost1 undoubtedly stimulated others to attempt to approximate to these results at less cost2 and there are now many forms of wheel of low cost giving fully double the power1 with the same consumption of water1 that was obtained from most of the older forms of wheels of the same class4 ,,anchor ,,ice4 ,a frequent inconvenience in the use of water power in cold climates is that peculiar form of ice called anchor or ground ice4 ,it adheres to stones1 gravel1 wood1 and other substances forming the beds of streams1 the channels of conduits1 and orifices through which water is drawn1 sometimes raising the level of water courses many feet by its accumulation on the bed1 and entirely closing small orifices through which water is drawn for industrial purposes4 ,i have been for many years in a position to observe its effects and the conditions under which it is formed4 ,the essential conditions are1 that the temperature of the water is at its freezing point1 and that of the air below that point2 the surface of the water must be exposed to the air1 and there must be a current in the water4 ,the ice is formed in small needles on the surface1 which would remain there and form a sheet if the surface was not too much agitated1 except for a current or movement in the body of water sufficient to maintain it in a constant state of intermixture4 ,even when flowing in a regular channel there is a continued interchange of position of the different parts of a stream2 the retardation of the bed causes variations in the velocity1 which produce whirls and eddies and a general instability in the movement of the water in different parts of the section--the result being that the water at the bottom soon finds its way to the surface1 and the reverse4 ,i found by experiments on straight canals in earth and masonry that colored water discharged at the bottom reached the surface at distances varying from ten to thirty times the depth4#a ,in natural water courses1 in which the beds are always more or less irregular1 the disturbance would be much greater4 ,the result is that the water at the surface of a running stream does not remain there1 and when it leaves the surface it carries with it the needles of ice1 the specific gravity of which differs but little from that of the water1 which1 combined with their small size1 allows them to be carried by the currents of water in any direction4 ,the converse effect takes place in muddy streams4 ,the mud is apparently held in suspension1 but is only prevented from subsiding by the constant intermixture of the different parts of the stream2 when the current ceases the mud sinks to the bottom1 the earthy particles composing it1 being heavier than water1 would sink in still water in times inversely proportional to their size and specific gravity4 ,this1 ,i think1 is a satisfactory explanation of the manner in which the ice formed at the surface finds its way to the bottom2 its adherence to the bottom1 ,i think1 is explained by the phenomenon of regelation1 first observed by ,faraday2 he found that when the wetted surfaces of two pieces of ice were pressed together they froze together1 and that this took place under water even when above the freezing point4 ,professor ,james ,d4 ,forbes found that the same thing occurred by mere contact without pressure1 and that ice would become attached to other substances in a similar manner4 ,regelation was observed by these philosophers in carefully arranged experiments with prepared surfaces fitting together accurately1 and kept in contact sufficiently long to allow the freezing together to take place4 ,in nature these favorable conditions would seldom occur in the masses of ice commonly observed1 but we must admit1 on the evidence of the recorded experiments1 that1 under particular circumstances1 pieces of ice will freeze together or adhere to other substances in situations where there can be no abstraction of heat4 ,footnote #a3 ,paper clx41 in the ,transactions of the ,society1 #ahgh1 vol4 vii41 pages #aji-afh4 ,when a piece of ice of considerable size comes in contact under water with ice or other substance1 it would usually touch in an area very small in proportion to its mass1 and other forces acting upon it1 and tending to move it1 would usually exceed the freezing force1 and regelation would not take place4 ,in the minute needles formed at the surface of the water the tendency to adhere would be much the same as in larger masses touching at points only1 while the external forces acting upon them would be extremely small in proportion1 and regelation would often occur1 and of the immense number of the needles of ice formed at the surface enough would adhere to produce the effect which we observe and call anchor ice4 ,the adherence of the ice to the bed of the stream or other objects is always downstream from the place where they are formed2 in large streams it is frequently many miles below2 a large part of them do not become fixed1 but as they come in contact with each other1 regelate and form spongy masses1 often of considerable size1 which drift along with the current1 and are often troublesome impediments to the use of water power4 ,water powers supplied directly from ponds or rivers1 or canals frozen over for along distance immediately above the places from which the water is drawn1 are not usually troubled with anchor ice1 which1 as ,i have stated1 requires open water1 upstream1 for its formation4 99 99 99 99 99 ,a ,,pair ,,of ,,cottages4 ,this drawing has been admitted into the ,exhibition of the ,royal ,academy this year4 ,the cottages are of red brick1 tiled roof1 white woodwork1 as usual1 rough-cast in the gables2 but they are not built yet4 ,design of ,arthur ,cawston4--,building ,news4 ,illustration3 ,,suggestions ,,in ,,architecture4--,a ,,pair ,,of ,,english ,,cottages4--,,by ,a4 ,,cawston4 99 99 99 99 99 ,,delicate ,,scientific ,,instruments4 ,by ,,edgar ,l4 ,,larkin1 ,new ,windsor ,observatory1 ,new ,windsor1 ,illinois4 ,within the past five years1 scientific men have surpassed previous efforts in close measurement and refined analysis4 ,by means of instruments of exceeding delicacy1 processes in nature hitherto unknown1 are made palpable to sense4 ,heat is found in ice1 light in seeming darkness1 and sound in apparent silence4 ,it seems that physicists and chemists have almost if not quite reached the ultimate atoms of matter4 ,the mechanism must be sensitive1 as such properties of matter as heat1 light1 electricity1 magnetism1 and actinism1 are to be handled1 caused to vanish and reappear1 analyzed and measured4 ,with such instruments nature is scrutinized1 revealing new properties1 strange motions1 vibrations1 and undulations4 ,throughout the visible universe1 the faintest pulsations of atoms are detected1 and countless millions of infinitely small waves1 bearing light1 heat1 and sound1 are discovered and their lengths determined4 ,refined spectroscopic analysis of light is now made so that when any material burns1 no matter what its distance1 its spectrum tells what substance is burning4 ,when any luminous body appears1 it can be told whether it is approaching or receding1 or whether it shines by its own or reflected light2 whence it is seen that rays falling on earth from a flight of a hundred years1 are as sounding lines dropped in the appalling depths of space4 ,we wish to describe a few of these intricate instruments1 and mention several far-reaching discoveries made by their use2 beginning with mechanism for the manipulation of light4 ,optics is based on the accidental discovery that a piece of glass of certain shape will draw light to a focus1 forming an image of any object at that point4 ,the next step was in learning that this image can be viewed with a microscope1 and magnified2 thus came the telescope revealing unheard of suns and galaxies4 ,the first telescopes colored everything looked at1 but by a hundred years of mathematical research1 the proper curvature of objectives formed of two glasses was discovered1 so that now we have perfect instruments4 ,great results followed2 one can now peer into the profound solitudes of space1 bringing to view millions of stars1 requiring light #e1jjj years to traverse their awful distance1 and behold suns wheeling around suns1 and thousands of nebul1 or agglomerations of stars so distant as to send us confused light1 appearing like faint gauze like structures in measureless voids4 ,the modern telescope has astonishing power1 thus3 ,when ,mr4 ,clark finished the great twenty-six-inch equatorial1 now at ,washington1 he tested its seeing properties4 ,a photographic calligraph1 whose letters were so fine as to require a microscope to see them1 was placed at a distance of three hundred feet4 ,mr4 ,clark turned the great eye upon the invisible thing and read the writing with ease4 ,but a greater feat than this was accomplished by the same instrument-- the discovery of the two little moons of ,mars1 by ,prof4 ,asaph ,hall1 in #ahgg4 ,they are so small as to be incapable of measurement by ordinary means1 but with an ingenious photometer devised by ,prof4 ,pickering of ,harvard ,college1 he determined the outer satellite to be six and the inner seven miles in diameter4 ,the discovery of these minute bodies seems past belief1 and will appear more so1 when it is told that the task is equal to that of viewing a luminous ball two inches in diameter suspended above ,boston1 by the telescope situated in the city of ,new ,york4 7,newcomb and ,holden's ,astronomy1 p4 #cch47 ,phobos1 the nearest moon1 is only #d1jjj miles from the surface of ,mars1 and is obliged to move with such great velocity to prevent falling1 that it actually makes a circuit about its primary in only seven hours and thirty-eight minutes4 ,but ,mars turns on its axis in twenty-four hours and thirty-seven minutes1 so the moon goes round three times1 while ,mars does once1 hence it rises in the west and sets in the east1 making one day of ,mars equal three of its months4 ,this moon changes every two hours1 passing all phases in a single martial night2 is anomalous in the solar system1 and tends to subvert that theory of cosmic evolution wherein a rotating gaseous sun cast off concentric rings1 afterward becoming planets4 ,astronomers were not satisfied with the telescope2 true1 they beheld the phenomena of the solar system2 planets rotating on axes1 and satellites revolving about them4 ,they saw sunspots1 facul1 and solar upheaval2 watched eclipses1 transits1 and the alternations of summer and winter on ,mars1 and detected the laws of gravity and motion in the system to which the earth belongs4 ,they then devised the micrometer4 ,this is a complex mechanism placed in the focus of a telescope1 and by its use any object1 providing it shows a disk1 no matter what its distance1 can be measured4 ,it consists of spider webs set within a graduated metallic circle1 the webs movable by screws1 and the whole instrument capable of rotating about the collimation axis of the telescope4 ,the screw head is a circle ruled to degrees and minutes1 and turns in front of a fixed vernier in the field of a reading microscope4 ,one turn of the screw moves the web a certain number of seconds2 then as there are #cfj in a circle1 one-three-hundred-and-sixtieth of a turn moves the web one-three-hundred and-sixtieth of the amount1 and so on4 ,thus1 when two stars are seen in the field1 one web is moved by the screw until the fixed line and the movable one are parallel1 each bisecting a star4 ,by reading with the microscope the number of degrees turned1 the distance apart of the stars becomes known2 the distance being learned1 position is then sought2 the observance of which led to one of the greatest discoveries ever made by man4 ,the permanent line of the micrometer is placed in the line joining the north and south poles of the heavens1 and brought across one of the stars2 the movable web is then rotated until it bisects the other1 and then the angle between the webs is recorded4 ,double stars are thus measured1 first in distance1 and second1 their position4 ,after this1 if any movement of the stars takes place1 the tell tale micrometer at once detects it4 ,in #aghj1 ,sir ,wm4 ,herschel measured double stars and made catalogues with distances and positions4 ,within twenty years1 he startled intellectual man with the statement that many of the fixed stars actually move--one great sun revolving around another1 and both rotating about their common center of gravity4 ,if we look at a double star with a small telescope1 it looks just like any other2 using a little larger glass1 it changes appearance and looks elongated2 with a still better telescope1 they become distinctly separated and appear as two beautiful stars whose elements are measured and carefully recorded1 in order to see if they move4 ,herschel detected the motion of fifty of these systems1 and revolutionized modern astronomy4 ,astronomers soared away from the little solar system1 and began a minute search throughout the whole sidereal heavens4 ,herschel's catalogue contained four hundred double suns1 only fifty of which were known to be in revolution4 ,since then1 enormous advance has been made4 ,the micrometer has been improved into an instrument of great delicacy1 and the number of doubles has swelled to ten thousand2 six hundred and fifty of them being known to be binary1 or revolving on orbits--,prof4 ,s4 ,w4 ,burnham1 the distinguished young astronomer of the ,dearborn ,observatory1 ,chicago1 having discovered eight hundred within the last eight years4 ,this discovery implies stupendous motion2 every fixed star is a sun like our own1 and we can imagine these wheeling orbs to be surrounded by cool planets1 the abode of life1 as well as ours4 ,if the orbit of a binary system lies edgewise toward us1 then one star will hide the other each revolution1 moving across it and appearing on the other side4 ,several instances of this motion are known2 the distant suns having made more than a complete circuit since discovery1 the shortest periodic time known being twenty-five years4 ,wonderful as was this achievement of the micrometer1 one not less surprising awaited its delicate measurement4 ,if one walks in a long street lighted with gas1 the lights ahead will appear to separate1 and those in the rear approach4 ,the little spider lines have detected just such a movement in the heavens4 ,the stars in ,hercules are all the time growing wider apart1 while those in ,argus1 in exactly the opposite part of the ,universe1 are steadily drawing nearer together4 ,this demonstrates that our sun with his stately retinue of planets1 satellites1 comets1 and meteorites1 all move in grand march toward the constellation ,hercules4 ,the entire universe is in motion4 ,but these revelations of the micrometer are tame compared with its final achievement1 the discovery of parallax4 ,this means difference of direction1 and the parallax of a star is the difference of its direction when viewed at intervals of six months4 ,astronomers observe a star to-day with a powerful telescope and micrometer2 and in six months again measure the same star4 ,but meanwhile the earth has moved #ahc1jjj1jjj miles to the east1 so that if the star has changed place1 this enormous journey caused it1 and the change equals a line #ia1djj1jjj miles long as viewed from the star4 ,for years many such observations were made2 but behold the star was always in the same place2 the whole distance of the sun having dwindled down to the diameter of a pin point in comparison with the awful chasm separating us from the stars4 ,finally micrometers were made that measured lines requiring #ajj1jjj to make an inch2 and a new series of observations begun1 crowning the labors of a century with success4 ,finite man actually told the distance of the starry hosts and gauged the universe4 ,when the parallax of any object is found1 its distance is at once known1 for the parallax is an arc of a circle whose radius is the distance4 ,by an important theorem in geometry it is learned1 that when anything subtends an angle of one second its distance is #bjf1bfe times its own diameter4 ,the greatest parallax of any star is that of ,alpha ,centauri--nine-tenths of a second2 hence it is more than #bjf1bfe times #ia1djj1jjj miles--the distance of the sun--away1 or twenty thousand billions of miles4 ,this is the distance of the nearest fixed star1 and is used as a standard of reference in describing greater depths of space4 ,this is not all the micrometer enables man to know1 ,when the distance separating the earth from two celestial bodies that revolve is learned1 the distance between the two orbs becomes known4 ,then the period of revolution is learned from observation1 and having the distance and time1 then their velocity can be determined4 ,the distance and velocity being given1 then the combined weights of both suns can be calculated1 since by the laws of gravity and motion it is known how much weight is required to produce so much motion in so much time1 at so much distance1 and thus man weighs the stars4 ,if the density of these bodies could be ascertained1 their diameters and volumes would be known1 and the size of the fixed stars would have been measured4 ,density can never be exactly learned2 but strange to say1 photometers measure the quantity of light that any bright body emits2 hence the stars cannot have specific gravity very far different from that of the sun1 since they send similar light1 and in quantity obeying the law wherein light varies inversely as the squares of distance4 ,therefore1 knowing the weight and having close approximation to density1 the sizes of the stars are nearly calculated4 ,the conclusion is now made that all suns within the visible universe are neither very many times larger nor smaller than our own4 7,newcomb and ,holden's ,astronomy1 p4 #ded47 ,another result followed the use of the micrometer3 the detection of the proper motion of the stars4 ,for several thousand years the stars have been called fixed1 but the fine rulings of the filar micrometer tell a different story4 ,there are catalogues of several hundred moving stars1 whose motion is from one-half second to eight seconds annually4 ,the binary star1 ,sixty-one ,cygni1 the nearest north of the equator1 moves eight seconds every year1 a displacement equal in three hundred and sixty years to the apparent diameter of the moon4 ,the fixed stars have no general motion toward any point1 but move in all directions4 ,thus the micrometer revealed to man the magnitude and general structure1 together with the motions and revolutions of the sidereal heavens4 ,above all1 it demonstrated that gravity extends throughout the universe4 ,still the longings of men were not appeased2 they brought to view invisible suns sunk in space1 and told their weight1 yet the thirst for knowledge was not quenched4 ,men wished to know what all the suns are made of1 whether of substances like those composing the earth1 or of kinds of matter entirely different4 ,then was devised the spectroscope1 and with it men audaciously questioned nature in her most secluded recesses4 ,the basis of spectroscopy is the prism1 which separates sunlight into seven colors and projects a band of light called a spectrum4 ,this was known for three hundred years1 and not much thought of it until ,fraunhofer viewed it with a telescope1 and was surprised to find it filled with hundreds of black lines invisible to the unaided eye4 ,could it be possible that there are portions of the solar surface that fail to send out light8 ,such is the fact1 and then began a twenty years' search to learn the cause4 ,the lines in the solar spectrum were unexplained until finally metals were vaporized in the intense heat of the electric arc and the light passed through a spectroscope1 when behold the spectra of metals were filled with bright lines in the same places as were the dark lines in the spectrum of the sun4 ,another step3 if when metals are volatilized in the arc1 rays of light from the sun are passed through the vapor and allowed to enter the spectroscope1 a great change is wrought2 a reversal takes place1 and the original black bands reappear4 ,a new law of nature was discovered1 thus3 ,vapors of all elements absorb the same rays of light which they emit when incandescent4 ,every element makes a different spectrum with lines in different places and of different widths4 ,these have been memorized by chemists1 so that when an expert having a spectroscope sees anything burn he can tell what it is as well as read a printed page4 ,men have learned the alphabet of the universe1 and can read in all things radiating light1 the constituent elements4 ,the black lines in the solar spectrum are there because in the atmosphere of the sun exist vapors of metals1 and the light from the liquid metals below is unable to pass through and reach the earth1 being absorbed kind for kind4 ,gaseous iron sifts out all rays emitted from melted iron1 and so do the vapors of all other elements in the sun1 radiating light in unison with their own4 ,sodium1 iron1 calcium1 hydrogen1 magnesium1 and many other substances are now known to be incandescent in the sun and stars2 and the results of the developments of the spectroscope may be summed up in the generalization that all bodies in the universe are composed of the same substance the earth is4 ,the sun is subject to terrific hurricanes and cyclones1 as well as explosions1 casting up jets to the height of #bjj1jjj miles4 ,in the early days of spectroscopy these protuberances could only be seen at a time of a total solar ellipse1 and astronomers made long journeys to distant parts of the earth to be in line of totality4 ,now all is changed4 ,images of the sun are thrown into the observatory by an ingenious instrument run by clockwork1 and called a heliostat4 ,this is set on the sun at such an angle as to throw the solar image into the objective of the telescope placed horizontally in a darkened observatory1 and the pendulum ball set in motion1 when it will follow the sun without moving its image1 all day if desired4 ,at the eye end of the telescope is attached the spectroscope and the micrometer1 and the whole set of instruments so adjusted that just the edge of the sun is seen1 making a half spectrum4 ,the other half of the spectroscope projects above the solar limb1 and is dark1 so if an explosion throws up liquid jets1 or flames of hydrogen1 the astronomer at once sees them and with the micrometer measures their height before they have time to fall4 ,and the spectrum at once tells what the jets are composed of1 whether hydrogen1 gaseous iron1 calcium1 or anything else4 ,prof4 ,c4 ,a4 ,young saw a jet of hydrogen ascend a distance of #bjj1jjj miles1 measured its height1 noted its spectrum and timed its ascent by a chronometer all at once1 and was astonished to find the velocity one hundred and sixty miles per second--eight times faster than the earth flies on its orbit4 ,by these improvements solar hurricanes1 whirlpools1 and explosions can be seen from any physical observatory on clear days4 ,the slit of the spectroscope can be moved anywhere on the disk of the sun2 so that if the observer sees a tornado begin1 he moves the slit along with it1 measures the length of its tract and velocity4 ,with the telescope1 micrometer1 heliostat1 and spectroscope came desire for more complex instruments1 resulting in the invention of the photoheliograph1 invoking the aid of photography to make permanent the results of these exciting researches4 ,this mechanism consists of an excessively sensitive plate1 adjusted in the solar focus of the telespectroscope4 ,in front of the plate in the camera is a screen attached to a spring1 and held closed by a cord4 ,the eye is applied to the spectroscopic end of the complex arrangement to watch the development of solar hurricanes4 ,finally an appalling outburst occurs2 the flames leap higher and higher1 torn into a thousand shreds1 presenting a scene that language is powerless to describe4 ,when the display is at the height of its magnificence1 the astronomer cuts the cord2 the slide makes an exposure of one-three thousandth part of a second1 and an accurate photograph is taken4 ,the storm all in rapid motion is petrified on the plate2 everything is distinct1 all the surging billows of fire1 boilings1 and turbulence are rendered motionless with the velocity of lightning4 ,at ,meudon1 in ,france1 ,m4 ,janssen takes these instantaneous photographs of the sun1 thirty inches in diameter1 and afterward enlarges them to ten feet2 showing scenes of fiery desolation that appalls the human imagination4 7,see address of ,vice ,president ,langley1 ,a4 ,a4 ,a4 ,s41 ,proceedings ,saratoga ,meeting1 p4 #ef47 ,this huge photograph can be viewed in detail with a small telescope and micrometer1 and the crests of solar waves measured4 ,many of these billows of fire are in dimensions every way equal in size to the ,state of ,illinois4 ,binary stars are photographed so that in time to come they can be retaken1 when if they have moved1 the precise amount can be measured4 ,another instrument is the telepolariscope1 to be attached to a telescope4 ,it tells whether any luminous body sends us its own1 or reflected light4 ,only one comet bright enough to be examined has appeared since its perfection4 ,this was ,coggia's1 and was found to reflect solar from the tail1 and to radiate its own light from the nucleus4 ,still another intricate instrument is in use1 the thermograph1 that utilizes the heat rays from the sun1 instead of the light4 ,it takes pictures by heat2 in other words1 it sees in the dark2 brings invisible things to the eye of man1 and is used in astronomical and physical researches wherein undulations and radiations are concerned4 ,and now comes the magnetometer1 to measure the amount of magnetism that reaches the earth from the sun4 ,it points to zero when the magnetic forces of the earth are in equilibrium1 but let a magnetic storm occur anywhere in the world and the pointer will move by invisible power4 ,it detects a close relation between the magnetism of the earth and sun4 ,the needle is deflected every time a solar disturbance takes place4 ,at ,kew1 ,england1 an astronomer was viewing the sun with a telescope and observed a tongue of flame dart across a spot whose diameter was thirty-three thousand seven hundred miles4 ,the magnetometer was violently agitated at once1 showing that whatever magnetism may be1 its influence traversed the distance of the sun with a velocity greater than that of light4 ,not less remarkable is the new instrument1 the thermal balance1 devised by ,prof4 ,s4 ,p4 ,langley1 ,pittsburgh4 ,it will measure the one-fifty-thousandth part of a degree of heat1 and consists of strips of platinum one-thirty-second of an inch wide and one-fourth of an inch long2 and so thin that it requires fifty to equal the thickness of tissue paper1 placed in the circuit of electricity running to a galvanometer4 ,when mounted in a reflected telescope it will record the heat from the body of a man or other animal in an adjoining field1 and can do so at great distances4 ,it will do this equally well at night1 and may be said1 in a certain sense1 to give the power of seeing in the dark4 7,science1 issue of ,jan4 #h1ahha1 p4 #ab47 ,it is expected to reveal great facts concerning the heat of the stars4 ,indeed1 the thermopile in the hands of ,lockyer has already made palpable the heat of the fixed stars4 ,he placed the little detective in the focus of a telescope and turned it on ,arcturus4 ,the result was this1 that the heat received from ,arcturus1 when at an altitude of #ee1 was found to be just equal to that received from a cube of boiling water1 three inches across each side1 at the distance of four hundred yards2 and the heat from ,vega is equal to that from the same cube at six hundred yards4 7,lockyer's ,star ,gazing1 p4 #che47 ,thus that inscrutable mode of force heat traverses the depths of space1 reaches the earth1 and turns the delicate balance of the thermopile4 ,another discovery was made with the spectroscope2 thus1 if a boat moves up a river1 it will meet more waves than will strike it if going down stream4 ,light is the undulation of waves2 hence if the spectroscope is set on a star that is approaching the earth1 more waves will enter than if set on a receding star1 which fact is known by displacement of lines in the spectroscope from normal positions4 ,it is found that many fixed stars are approaching1 while others are moving away from the solar system4 ,we cannot note the researches of ,edison1 ,lockyer1 or ,tyndall1 nor of ,crookes1 who has seemingly reached the molecules whence the universe is composed4 ,the modern observatory is a labyrinth of sensitive instruments2 and when any disturbance takes place in nature1 in heat1 light1 magnetism1 or like modes of force1 the apparatus note and record them4 ,men are by no means satisfied4 ,insatiable thirst to know more is developing into a fever of unrest2 they are wandering beyond the limits of the known1 every day a little farther4 ,they survey space1 and interrogate the infinite2 measure the atom of hydrogen and weigh suns4 ,man takes no rest1 and neither will he until he shall have found his own place in the chain of nature4--,kansas ,review4 99 99 99 99 99 ,,the ,,future ,,development ,,of ,,electrical ,,appliances4 ,prof4 ,j4 ,perry lately delivered a lecture on this subject at the ,society of ,arts1 ,london1 which contains in an epitomized form the salient points of the hopes and fears of the more sanguine spirits of the electrical world4 ,prof4 ,perry is one of the two professors who have been dubbed the ,japanese ,twins1 and whose insatiate love of work induced one of our most celebrated men of science to say that they caused the center of experimental research to tend toward ,tokyo instead of ,london4 ,professors ,ayrton and ,perry have for some time been again resident in ,england1 but it is evident that they did not leave any of their energy in ,japan1 for those who know them intimately1 know that they are pursuing numerous original investigations1 and that so soon as one is finished1 another is commenced4 ,it would have been difficult then to have found an abler exponent of the future of electricity4 ,prof4 ,perry1 after referring to what might have been said of the great things physical science has done for humanity1 plunged into his subject4 ,the work to be done was vast1 and the workers altogether out of proportion to the task4 ,the methods of measurement of electricity are not generally understood4 ,perhaps when electricity is supplied to every house in the city at a certain price per horse power1 and is used by private individuals for many different purposes1 this ignorance will disappear4 ,electrical energy is obtained in various ways1 but the generators get heated2 and one great object of inventors is to obtain from machines as much as possible electrical energy of the energy in the first place supplied to such machine4 ,the lecturer called particular attention to the difference between electricity and electrical energy1 and attempted to drive home the fundamental conceptions of electrical science by the analogies derivable from hydraulics4 ,a miller speaks not only of quantity of water1 but also of head of water4 ,the statement then of quantity of electricity is insufficient1 except we know the electrical property analogous to head of water1 and which is termed electrical potential4 ,a small quantity of electricity of high potential is similar to a small quantity of water at high level4 ,the analogies between water and electricity were collected in the form of a table shown on a wall sheet as follows3 ,we ,want to ,use ,water4 ,we ,want to ,use ,electricity4 #a4 ,steam pump burns coal1 #a4 ,generator burns zinc1 or and lifts water to a higher uses mechanical power1 and level4 lifts electricity to a higher level or potential4 #b4 ,energy available is #b4 ,energy available is amount of water lifted x amount of electricity x difference difference of level4 of potential4 #c4 ,if we let all the water #c4 ,if we let all the electricity flow away through channel flow through a wire from one to lower level without doing screw of our generator to the work1 its energy is all other without doing work1 all converted into heat because the electrical energy is of frictional resistance of converted into heat because of pipe or channel4 resistance of wire4 #d4 ,if we let water work a #d4 ,if we let our electricity hoist as well as flow through work a machine as well as channels1 less water flows flow through wires1 less flows than before1 less power is than before1 less power is wasted in friction4 wasted through the resistance of the wire4 #e4 ,however long and narrow #e4 ,however long and thin may be the channels1 the wires may be1 electricity water maybe brought from may be brought from any distance distance1 however great1 however great1 to give to give out almost all its out almost all its original original energy to a hoist4 energy to a machine4 ,this requires ,this requires a great head a great difference of and small quantity of water4 potentials and a small current4 ,the difference between potential and electro-motive force was explained thus3 difference of potential is analogous with difference of pressure or head of water1 howsoever produced2 whereas electromotive force is analogous with the difference of pressure before and behind a slowly moving piston of the pump employed by an unfortunate miller to produce his water supply4 ,electricians have very definite ideas upon the subject they are working at1 and especial attention is paid to the measurements on which their work depends4 ,examples of these measurements were shown by the following tables on wall sheets3 ,,electrical ,,magnitudes 7,,some ,,rather ,,approximate74 ,resistance of ,one yard of copper wire1 one-eighth of an inch diameter4444444444444444444444444444444# j4jjb ohms4 ,one mile ordinary iron telegraph wire1 444444444#aj to #bj ,some of our selenium cells 4444444444444 #dj to #a1jjj1jjj ,a good telegraph insulator 44444444444 #d1jjj1jjj1jjj1jjj ,electro-motive force of ,a pair of copper-iron junctions at a difference of temperature of #a deg4 ,fah444444444 #j4jjjj volt4 ,contact of zinc and copper 444444444444444444444 #j4ge ,one ,daniell's cell 44444444444444444444444444444 #a4a ,mr4 ,latimer ,clark's standard cell 44444444444444 #a4de ,one of ,dr4 ,de la ,hue's batteries 444444 #aa1jjj ,lightning flashes probably many millions of volts4 ,current measured by us in some experiments3 ,using electrometer4444444 almost infinitely small currents4 ,using delicate galvanometer #j4jj1jjj1jjj1jdj weber4 ,current received from ,atlantic cable1 when #be words per minute are being sent 4444444444444444 #j4jjj1jja weber ,current in ordinary land telegraph lines 4444444444444444444444444 #j4jjc weber ,current from dynamo machine4444 #e to #ajj weber ,in any circuit1 current in webers electro-motive force in volts _/ resistance in ohms4 ,,rate ,,of ,,production ,,of ,,heat1 ,,calculated ,,in ,,the ,,shape ,,of ,,horse-,,power4 ,in the whole of a circuitcurrent in webers x electro-motive force in volts _/ #gdf4 ,in any part of circuitcurrent in webers x difference of potential at the two ends of the part of the circuit in question _/ #gdf4 ,or1 square of current in webers x resistance of the part in ohms _/ #gdf4 ,if there are a number of generators of electricity in a circuit1 whose electromotive forces in volts are ,e#a1 ,e#b1 etc41 and if there are also opposing electro-motive forces4 ,f#a1 ,f#b1 etc41 volts1 and if ,c is the current in webers1 ,r the whole resistance of the current in ohms1 ,p the total horse-power taken at the generators1 ,q the total horse-power converted into some other form of energy1 and given out at the places where there are opposing electro-motive forces1 ,h the total horse-power wasted in heat1 because of resistance1 then3 7,e#a;,e#b;etc47-7,f#a;,f#b;etc47 ,c ----------------------------- ,r ,,tex3 ,c frac7,e#a;,e#btextetc47-7,f#a;,f#btextet c47,r ,c ,c ,p ---77,e#a;,e#b;etc472 ,q ---7,f#a;,f#b;etc47 #gdf #gdf ,,tex3 frac,c#gdf7;,e#a;,e#btextetc472 ,q frac,c#gdf7;,f#a;,f#btextetc47 ,c ,r ,h ----- 4 #gdf ,,tex3 ,h frac,c#b ,r#gdf4 ,the lifting power of an electro-magnet of given volume is proportional to the heat generated against resistance in the wire of the magnet4 ,the future of many electrical appliances depends on how general is the public comprehension of the lessons taught by these wall sheets4 ,if a few capitalists in ,london would only spend a few days in learning thoroughly what these mean1 electrical appliances of a very distant future would date from a few months hence4 ,a number of experiments were shown1 in some of which electrical energy was converted into heat1 in others into sound1 in others into work4 ,at this part of the lecture reference was made to the work of ,prof4 ,ayrton and his pupils at ,cowper street 7,city and ,guilds of ,london ,institute ,classes74 ,they measure 7#a7 the gas consumed by the engine1 7#b7 the horse-power given to the dynamo machine1 7#c7 the current in the circuit in webers1 and 7#d7 the resistance of the circuit4 ,thus exact calculations can now be made as to the horse power expended in any part of the circuit1 and the light given out in any given period by an electric lamp4 ,the dynamometers used in these measurements were described1 but at present1 in some cases1 the description given is for various reasons incomplete1 so that we shall take a future opportunity of writing of these instruments4 ,to measure the light a photometer1 constructed by ,profs4 ,ayrton and ,perry1 is used1 which obviates the necessity of large rooms1 and enables the operator to give the intensity in a very short period of time4 ,a number of measurements of the illuminating power of an electric lamp were rapidly made during the lecture with this photometer4 ,by means of a small dynamo machine1 driven by an electric current generated in the ,adelphi arches1 a ventilator1 a sewing machine1 a lathe1 etc41 were driven2 in the latter a piece of wood was turned4 ,what1 said the lecturer1 do these examples show you8 ,they show that if ,i have a steam-engine in my back yard ,i can transmit power to various machines in my house1 but if you measured the power given to these machines you would find it to be less than half of what the engine driving the outside electrical machine gives out4 ,further1 when we wanted to think of heating of buildings and the boiling of water1 it was all very well to speak of the conversion of electrical energy into heat1 but now we find that not only do the two electrical machines get heated and give out heat1 but heat is given out by our connecting wires4 ,we have then to consider our most important question4 ,electrical energy can be transmitted to a distance1 and even to many thousands of miles1 but can it be transformed at the distant place into mechanical or any other required form of energy1 nearly equal in amount to what was supplied8 ,unfortunately1 ,i must say that hitherto the practical answer made to us by existing machines is1 ',no2' there is always a great waste due to the heat spoken of above4 ,but1 fortunately1 we have faith in the measurements1 of which ,i have already spoken1 in the facts given us by ,joule's experiments and formulated in ways we can understand4 ,and these facts tell us that in electric machines of the future1 and in their connecting wires1 there will be little heating1 and therefore little loss4 ,we shall1 ,i believe1 at no distant date1 have great central stations1 possibly situated at the bottom of coal-pits where enormous steam engines will drive enormous electric machines4 ,we shall have wires laid along every street1 tapped into every house1 as gas-pipes are at present2 we shall have the quantity of electricity used in each house registered1 as gas is at present1 and it will be passed through little electric machines to drive machinery1 to produce ventilation1 to replace stoves and fires1 to work apple-parers and mangles and barbers' brushes1 among other things1 as well as to give everybody an electric light4 ,it is possible1 as ,prof4 ,ayrton first showed in his ,sheffield lecture1 that electrical energy can be transmitted through long distances by means of small wires1 and that the opinion that wires of enormous thickness would be required is erroneous4 ,the desideratum required was good insulation4 ,he also showed that1 instead of a limiting efficiency of #ej per cent41 the only thing preventing our receiving the whole of our power was the mechanical friction which occurs in the machines4 ,he showed1 in fact1 how to get rid of electrical friction4 ,a machine at ,niagara receives mechanical power1 and generates electricity4 ,call this the generator4 ,let there be ,wires to another electric machine in ,new ,york1 which will receive electricity1 and give out mechanical work4 ,now this machine1 which may be called the motor1 produces a back electromotive force1 and the mechanical power given out is proportional to the back electromotive force multiplied into the current4 ,the current1 which is1 of course1 the same at ,niagara as at ,new ,york1 is proportional to the difference of the two electromotive forces1 and the heat wasted is proportional to the square of the current4 ,you see1 from the last table1 that we have the simple proportion3 power utilized is to power wasted1 as the back electromotive force of the motor is to the difference between electromotive forces of generator and motor4 ,this reason is very shortly and yet very exactly given as follows3 ,let electromotive force of generator be ,e2 of motor ,f4 ,let total resistance of circuit be ,r4 ,then if we call ,p the horse-power received by the generator at ,niagara1 ,q1 the horse-power given out by motor at ,new ,york1 that is1 utilized2 ,h1 the horse-power wasted as heat in machines and circuit2 ,c1 the current flowing through the circuit3 ,c7,e-,f7 _/ ,r ,p,e7,e-,f7 _/ 7#gdf ,r7 ,q,f7,e-,f7 _/ 7#gdf ,r7 ,h7,e-,f7#b _/ 7#gdf ,r7 ,q3,h33,f3,e-,f ,the water analogy was again called into play in the shape of a model for the better demonstration of the problem4 ,the defects in existing electric machines and the means of increasing the ,e4,m4,f4 were discussed1 the conclusions pointing to the future use of very large machines and very high velocities4 ,the future of telephonic communication received a passing remark1 and attention called to the future of electric railways4 ,the small experiments of ,siemens have determined the ultimate success of this kind of railway4 ,their introduction is merely a question of time and capital4 ,the first cost of electric railways would be smaller than that of steam railways2 the working expenses would also be reduced4 ,the rails would be lighter1 the rolling stock lighter1 the bridges and viaducts less costly1 and in the underground railways the atmosphere would not be vitiated4 ,about two years ago1 it struck ,professor ,ayrton and myself1 when thinking how very faint musical sounds are heard distinctly from the telephone1 in spite of loud noises in the neighborhood1 that there was an application of this principle of recurrent effects of far more practical importance than any other1 namely1 in the use of musical notes for coast warnings in thick weather4 ,you will say that fog bells and horns are an old story1 and that they have not been particularly successful1 since in some states of the weather they are audible1 in others not4 ,now1 it seems to be forgotten by everybody that there is a medium of communicating with a distant ship1 namely1 the water1 which is not at all influenced by changes in the weather4 ,at some twenty or thirty feet below the surface there is exceedingly little disturbance of the water1 although there may be large waves at the surface4 ,suppose a large water-siren like this--experiment shown--is working at as great a depth as is available1 off a dangerous coast1 the sound it gives out is transmitted so as to be heard at exceedingly great distances by an ear pressed against a strip of wood or metal dipping into the water4 ,if the strip is connected with a much larger wooden or metallic surface in the water the sound is heard much more distinctly4 ,now1 the sides of a ship form a very large collecting surface1 and at the distance of several miles from such a water siren as might be constructed1 we feel quite sure that1 above the noise of engines and flapping sails1 above the far more troublesome noise of waves striking the ship's side1 the musical note of the distant siren would be heard1 giving warning of a dangerous neighborhood4 ,in considering this problem1 you must remember that ,messrs4 ,colladon and ,sturn heard distinctly the sound of a bell struck underwater at the distance of nearly nine miles1 the sound being communicated by the water of ,lake ,geneva4 ,the next portion of the lecture discussed the great value of a rapid recurrence of effects1 the obtaining of sound by means of a rapid intermission of light rays on selenium joined up in an electric circuit being instanced as an example4 ,then recent experiments on the refractive power of ebonite were detailed--the rough results tending to give greater weight to ,clerk-,maxwell's electro-magnetic theory of light4 ,the index of refraction of ebonite was found by ,profs4 ,ayrton and ,perry to be roughly #a4g4 ,clerk-,maxwell's theory requires that the square of this number should be equal to the electric specific inductive capacity of the substance4 ,for ebonite this electric constant varies from #b4b to #c4e for different specimens1 the mean of which is almost exactly equal to the square of #a4g4 99 99 99 99 99 ,,researches ,,on ,,the ,,radiant ,,matter ,,of ,,crookes ,,and ,,the ,,mechanical ,,theory ,,of ,,electricity4 ,by ,,dr4 ,w4 ,f4 ,,gintl1 abstracted by ,,dr4 ,,von ,,gerichten4 ,the author discusses the question whether1 according to the experiments of ,crookes1 the assumption of an especial fourth state of aggregation is necessary1 or whether the facts may be satisfactorily explained without such hypothesis8 ,he shows that the latter alternative is possible with the aid of a mechanical theory of electricity4 ,if the radiant matter produced in the vacuum is a phenomenon sui generis1 produced by the action of electricity and heat upon the molecules of gas remaining in the receiver1 it is1 in the first place1 doubtful to apply to it the conception of an aggregate condition4 ,the author considers it impossible to form a clear understanding of the phenomena in accordance with the theory of ,crookes1 or to find in the facts any evidence of the existence of radiant matter4 ,an explanation of the latter phenomenon is thus given3 ,particles become separated from the surface of the substance of the negative pole1 they are repelled1 and they move away from the pole with a speed resulting from the antagonistic forces in a parallel and rectilinear direction1 preserving their speed and their initial path so long as they do not meet with obstacles which influence their movement4 ,at a certain density of the gases present in the exhausted space1 these particles1 in consequence of the impact of gaseous molecules more or less opposed to their direction of movement1 lose their velocity after traveling a short distance and soon come to rest4 ,the more dilute the gas the smaller is the number of the impacts of the gaseous molecules encountering the molecules of the poles1 and at a certain degree of dilution the repelled polar particles will be able to traverse the space open to them without any essential alteration in their speed1 the small number of the existing gaseous molecules being no longer able to retard the molecules of the polar no their journey through the apparatus4 ,the luminous phenomena of the ,geissler tubes the author supposes to be produced by the intense blows which the gaseous molecules receive from the polar molecules flying rapidly through the apparatus4 ,the intensity of the luminous phenomena will naturally decrease with the number of the photophorous particles occupying the space4 ,accordingly in the experiments of ,crookes1 on continued rarefaction of the gas1 a condition was reached where a display of light is no longer perceptible1 or can be made visible merely by the aid of fluorescent bodies4 ,a condition may also appear1 as is shown by ,crookes' experiment1 with the metallic plate intercalated as negative pole in the middle of4 a ,geissler tube1 with the positive poles at the ends4 ,in this case the gaseous molecules are1 so to speak1 driven away by the polar particles endowed with an equal initial velocity1 till at a certain distance from the pole the mass of the gaseous molecules and their speed become so great that a luminous display begins4 ,in an analogous manner the author explains the phenomena of phosphorescence which ,crookes' elicits by the action of his radiant matter4 ,in like manner the thermic and the mechanical effects are most simply explained1 according to the expression selected by ,crookes himself1 as the results of a continued molecular bombardment4 ,the attraction of the so called radiant matter1 regarded as a stream of metallic particles by the magnet1 will not appear surprising4 99 99 99 99 99 ,,economy ,,of ,,the ,,electric ,,light4 ,mr4 ,w4 ,h4 ,preece writes to the ,journal of ,arts as follows3 ,at the ,south ,kensington ,museum1 very careful observations have been made on the relative cost of the two systems1 i4 e41 gas and electricity4 ,the court lighted is that known as the ,lord ,president's 7or the ,loan7 ,court4 ,it is #ach feet long by #aad feet wide1 and has an average height of about #db feet4 ,it is divided down the middle lengthwise by a central gallery4 ,there are cloisters all around it on the ground floor1 and the walls above are decorated in such a way that they do not assist in the reflection or diffusion of the light4 ,the absence of a ceiling--the court being sky-lighted--is to some extent compensated for by drawing the blinds under the sky-lights4 ,the experiments commenced about twelve months ago1 with eight lamps only on one side of the court4 ,the system was that of ,brush4 ,the dynamo machine was driven by an eight horse-power ,otto gas engine1 supplied by ,messrs4 ,crossley4 ,the comparison with the gas was so much in favor of electricity1 and the success of the experiment so encouraging1 that it was determined to light up the whole court4 ,the gas engine1 which was not powerful enough1 was replaced by a #ad-;horse power semi-portable steam engine1 by ,ransomes ,co41 of ,ipswich--an engine of sufficient power to drive double the required number of lights4 ,the dynamo machine is a ,no4 #g ,brush4 ,there are sixteen lamps in all--eight on each side of the court4 ,the machine has given no trouble whatever1 and it has1 as yet1 shown no signs of wear4 ,the lamps were not all good1 and it was found that they required careful adjustment1 but when once they were got to go right they continued to do so1 and have1 up to the present1 shown no signs of deterioration1 although the time during which they have been in operation is nine months4 ,the first outlay has been as follows3 ,engine and fixing1 including shafting and belting44444444444444444444444444444444 #dbj ,dynamo machine4444444444444444444444444 #djj ,lamps1 apparatus1 and conducting wire 4 #chd ------ #a1bjd ,the cost of working has been1 from ,june #bb1 to ,december #ca1 during which period the lights were going on #hg nights for a total time of #cei hours3 s4 d4 ,carbons4444444444444444444444444444444 #ah #i #j ,oil1 etc444444444444444444444444444444 #d #aa #f ,coal4444444444444444444444444444444444 #aa #ad #j ,wages444444444444444444444444444444444 #cd #g #f ---------- #fi #b #j being at the rate of #cs4 #aj;d4 per hour of light4 ,now1 the consumption of gas in the court would have been #d1hjj cubic feet per hour1 which1 at #cs4 #d;d4 per #a1jjj cubic feet1 would amount to #afs4 per hour1 thus showing a saving of working expenses of #abs4 #b;d4 per hour1 or1 since the museum is lit up for #gjj hours every year1 a total saving at the rate of #dbf per annum4 ,in estimating the cost as applied to this court1 only half the cost of the engine should be taken1 for a second dynamo machine has lately been added to light up some of the picture galleries1 and the ,life room of the ,art ,school4 ,the capital outlay should1 therefore1 be #iid4 ,in making a fair estimate of the annual cost1 we should also allow something for percentage on capital1 and something for wear and tear4 ,take-- s4 #e per cent1 on the capital44444444444444444444444444444 #di #aj #e per cent1 for wear and tear of electrical apparatus44 #ci #j #e per cent1 for depreciation of engines1 etc44444444444 #ba #j ------- ,total4444444444 #aji #aj leaving a handsome balance to the good of #caf #ajs4 as against gas4 ,the results of the working1 both practically and financially1 have proved to be1 at ,south ,kensington1 a decided success4 ,i am indebted to ,colonel ,festing1 ,r4,e41 who has charge of the lighting1 for these details4 ,the same comparison cannot be made at the ,british ,museum1 for no gas was used in the reading-room before the introduction of the electric light1 but the cost of lighting has proved to be #es4 #f;d4 per hour--at least one-third of that which would be required for gas4 ,the system in use at the ,museum is ,siemens'1 the engine being by ,wallis and ,steevens1 of ,basingstoke4 ,an excellent example of economic electric lighting1 is that of ,messrs4 ,henry ,tate ,sons1 sugar refinery1 ,silvertown4 ,a small ,tangye engine1 placed under the supervision of the driver of a large engine of the works1 drives an ',a' size ',gramme' machine1 which feeds a ',crompton' ',e' lamp4 ,this is hung at a height of about #ab feet from the ground in a single story shed1 about #hj feet long1 and #ej feet wide1 and having an open trussed roof4 ,the light1 placed about midway1 lengthways1 has a flat canvas frame1 forming a sort of ceiling directly over it1 to help to diffuse the illumination4 ,the whole of the shed is well lit2 and a large quantity of light also penetrates into an adjoining one of similar dimensions1 and separated by a row of columns4 ,the light is used regularly all through the night1 and has been so all through the winter4 ,messrs4 ,tate speak highly of its efficiency4 ,to ascertain the exact cost of the light1 as well as of the gas illumination which it replaced1 a gas-meter was placed to measure the consumption of the gas through the jets affected2 and also the carbons consumed by the electric illumination were noted4 ,a series of careful experiments showed that during a winter's night of #ad hours' duration the illumination by electricity cost #as4 #i;d41 while that by gas was #cs4 #f;d41 or #a;d4 per hour against #c;d4 per hour4 ,to this must be added the greatly increased illumination1 four to five times1 given by the electric light1 to the benefit of the work2 while this last illuminant also allowed1 during the process of manufacture of the sugar1 the delicate gradations of tint to be detected2 and so to avoid those mistakes1 sometimes costly ones1 liable to arise through the yellow tinge of gas illumination4 ,this alone would add much to the above-named economy1 arising from the use of electric illumination in sugar works4 ,i am indebted for these facts to ,mr4 ,j4 ,n4 ,shoolbred1 under whose supervision the arrangements were made4 ,some excellent experience has been gained at the shipbuilding docks in ,barrow-in-,furness1 where the ,brush system has been applied to illuminate several large sheds covering the punching and shearing machinery1 bending blocks1 furnaces1 and other branches of this gigantic business4 ,in one shed1 which was formerly lighted by large blast-lamps1 in which torch oil was burnt1 costing about #e;d4 per gallon1 and involving an expenditure of #h #is4 per week1 the electric light has been adopted at an expenditure of #d #ads4 per week4 ,the erecting shop1 #dej feet by #aej feet1 formerly dimly lit by gas at a cost of #bb per week1 is now efficiently lit by electricity at half the cost4 ,i am indebted for these facts to ,mr4 ,humphreys1 the manager of the works4 ,the ,post office authorities have contracted with ,mr4 ,m4 ,e4 ,crompton1 to light up the ,post-office at ,glasgow for the same price as they have hitherto paid for gas1 and there is no doubt that in many instances this arrangement will leave a handsome profit to the ,electric ,light ,company4 ,they are about to try the ,brockie system in the telegraph galleries1 and the ,brush system in the newspaper sorting rooms of the ,general ,post-office in ,st4 ,martin's-le-,grand4 99 99 99 99 99 ,,on ,,the ,,space ,,protected ,,by ,a ,,lightning-,,conductor4 ,by ,,william ,,henry ,,preece4 ,footnote3 ,from the ,philosophical ,magazine for ,december1 #ahhj4 ,any portion of non-conducting space disturbed by electricity is called an electric field4 ,at every point of this field1 if a small electrified body were placed there1 there would be a certain resultant force experienced by it dependent upon the distribution of electricity producing the field4 ,when we know the strength and direction of this resultant force1 we know all the properties of the field1 and we can express them numerically or delineate them graphically1 ,faraday 7,exp4 ,res41 #cabb et seq47 showed how the distribution of the forces in any electric field can be graphically depicted by drawing lines 7which he called lines of force7 whose direction at every point coincides with the direction of the resultant force at that point2 and ,clerk-,maxwell 7,camb4 ,phil4 ,trans41 #aheg7 showed how the magnitude of the forces can be indicated by the way in which the lines of force are drawn4 ,the magnitude of the resultant force at any point of the field is a function of the potential at that point2 and this potential is measured by the work done in producing the field4 ,the potential at any point is1 in fact1 measured by the work done in moving a unit of electricity from the point to an infinite distance4 ,indeed the resultant force at any point is directly proportional to the rate of fall of potential per unit length along the line of force passing through that point4 ,if there be no fall of potential there can be no resultant force2 hence if we take any surface in the field such that the potential is the same at every point of the surface1 we have what is called an equipotential surface4 ,the difference of potential between any two points is called an electromotive force4 ,the lines of force are necessarily perpendicular to the surface4 ,when the lines of force and the equipotential surfaces are straight1 parallel1 and equidistant1 we have a uniform field4 ,the intensity of the field is shown by the number of lines passing through unit area1 and the rate of variation of potential by the number of equipotential surfaces cutting unit length of each line of force4 ,hence the distances separating the equipotential surfaces are a measure of the electromotive force present4 ,thus an electric field can be mapped or plotted out so that its properties can be indicated graphically4 ,illustration3 ,fig4 #a ,the air in an electric field is in a state of tension or strain2 and this strain increases along the lines of force with the electromotive force producing it until a limit is reached1 when a rent or split occurs in the air along the line of least resistance--which is disruptive discharge1 or lightning4 ,illustration3 ,fig4 #b ,since the resistance which the air or any other dielectric opposes to this breaking strain is thus limited1 there must be a certain rate of fall of potential per unit length which corresponds to this resistance4 ,it follows1 therefore1 that the number of equipotential surfaces per unit length can represent this limit1 or rather the stress which leads to disruptive discharge4 ,hence we can represent this limit by a length4 ,we can produce disruptive discharge either by approaching the electrified surfaces producing the electric field near to each other1 or by increasing the quantity of electricity present upon them2 for in each case we should increase the electromotive force and close up1 as it were1 the equipotential surfaces beyond the limit of resistance4 ,of course this limit of resistance varies with every dielectric2 but we are now dealing only with air at ordinary pressures4 ,it appears from the experiments of ,drs4 ,warren ,de ,la ,rue and ,hugo ,muller that the electromotive force determining disruptive discharge in air is about #dj1jjj volts per centimeter1 except for very thin layers of air4 ,illustration3 ,fig4 #c ,if we take into consideration a flat portion of the earth's surface1 ,a ,b 7fig4 #a71 and assume a highly charged thunder-cloud1 ,c ,d1 floating at some finite distance above it1 they would1 together with the air1 form an electrified system4 ,there would be an electric field2 and if we take a small portion of this system1 it would be uniform4 ,the lines1 a b1 a' b'444would be lines of force2 and cd1 c' d'1 c d' 444would be equipotential planes4 ,if the cloud gradually approached the earth's surface 7,fig4 #b71 the field would become more intense1 the equipotential surfaces would gradually close up1 the tension of the air would increase until at last the limit of resistance of the air1 e f1 would be reached2 disruptive discharge would take place1 with its attendant thunder and lightning4 ,we can let the line1 e f1 represent the limit of resistance of the air if the field be drawn to scale2 and we can thus trace the conditions that determine disruptive discharge4 ,illustration3 ,fig4 #d ,if the earth-surface be not flat1 but have a hill or a building1 as ,h or ,l1 upon it1 then the lines of force and the equipotential planes will be distorted1 as shown in ,fig4 #c4 ,if the hill or building be so high as to make the distance ,h h or ,l l equal to e f 7,fig4 #b71 then we shall again have disruptive discharge4 ,if instead of a hill or building we erect a solid rod of metal1 ,g ,h1 then the field will be distorted as shown in ,fig4 #d4 ,now1 it is quite evident that whatever be the relative distance of the cloud and earth1 or whatever be the motion of the cloud1 there must be a space1 g g'1 along which the lines of force must be longer than a' a or ,h ,h'2 and hence there must be a circle described around ,g as a center which is less subject to disruptive discharge than the space outside the circle2 and hence this area may be said to be protected by the rod1 ,g ,h4 ,the same reasoning applies to each equipotential plane2 and as each circle diminishes in radius as we ascend1 it follows that the rod virtually protects a cone of space whose height is the rod1 and whose base is the circle described by the radius1 ,g a4 ,it is important to find out what this radius is4 ,illustration3 ,fig4 #e ,let us assume that a thunder-cloud is approaching the rod1 ,a ,b 7,fig4 #e71 from above1 and that it has reached a point1 ,d'1 where the distance4 ,d' ,b1 is equal to the perpendicular height1 ,d' ,c'4 ,it is evident that1 if the potential at ,d be increased until the striking-distance be attained1 the line of discharge will be along ,d' ,c or ,d' ,b1 and that the length1 ,a ,c'1 is under protection4 ,now the nearer the point ,d' is to ,d the shorter will be the length ,a ,c' under protection2 but the minimum length will be ,a ,c1 since the cloud would never descend lower than the perpendicular distance ,d ,c4 ,supposing1 however1 that the cloud had actually descended to ,d when the discharge took place4 ,then the latter would strike to the nearest point2 and any point within the circumference of the portion of the circle1 ,b ,c 7whose radius is ,d ,b71 would be at a less distance from ,d than either the point ,b or the point ,c4 ,hence a lightning-rod protects a conic space whose height is the length of the rod1 whose base is a circle having its radius equal to the height of the rod1 and whose side is the quadrant of a circle whose radius is equal to the height of the rod4 ,i have carefully examined every record of accident that was available1 and ,i have not yet found one case where damage was inflicted inside this cone when the building was properly protected4 ,there are many cases where the pinnacles of the same turret of a church have been struck where one has had a rod attached to it2 but it is clear that the other pinnacles were outside the cone2 and therefore1 for protection1 each pinnacle should have had its own rod4 ,it is evident also that every prominent point of a building should have its rod1 and that the higher the rod the greater is the space protected4 99 99 99 99 99 ,,photo-,,electricity ,,of ,,fluor-,,spar ,,crystals4 ,hantzel has communicated to the ,saxon ,royal ,society of ,science some interesting observations on the production of electricity by light in colored fluor-spar4 ,the centers of the fluor-spar cubes become negatively electric by the action of light4 ,the electric tension diminishes toward the edges and angles1 and frequently positive polarity is produced there4 ,with very sensitive crystals a short exposure to daylight is sufficient2 by a long exposure to light the electric current increases4 ,the direct rays of the sun act much more powerfully than diffused daylight1 and the electric carbon light is more powerful even than sunlight4 ,the photo-electric action of light belongs principally to the chemically active rays2 this is shown by the fact that the production of electricity is extremely small behind a glass colored with cuprous oxide1 and behind a film of a solution of quinine sulphate2 while it is not appreciably diminished by a film of a solution of alum4 ,the photo-electric excitability of fluor-spar crystals is increased by a moderate heat 7#hj to #ajj ,c474 99 99 99 99 99 ,,the ,,aurora ,,borealis ,,and ,,telegraph ,,cables4 ,the ,january and ,february numbers of the ,elektrotechnische ,zeitschrift contain a number of articles on this interesting subject by several eminent electricians4 ,professor ,foerster1 director of the observatory in ,berlin1 points out the great importance of the careful study of earth currents1 first observed at ,greenwich1 and now being investigated by a committee appointed by the ,german ,government4 ,he further points out1 according to ,professor ,wykander1 of ,lund1 in ,sweden1 that a close connection exists between earth currents1 the protuberances of the sun1 and the aurora borealis1 and that the nearly regular periodical reappearance of protuberances in intervals of eleven years coincides with similar periods of excessive magnetic earth currents and the appearance of the aurora borealis4 ,the remarkable disturbing influences on telegraph wires and cables of the aurora borealis observed from the #aath to #adth of ,august1 #ahhj1 have been carefully recorded by ,herr ,geh4 ,postnath ,ludwig in ,berlin1 and a map of ,europe compiled1 showing the places affected1 with the extent to which telegraph wires and cables were influenced and disturbed4 ,although the aurora was but faintly visible in ,england and ,germany1 and in ,russia only as far as #ce north1 disturbing influences were reported from all parts of ,europe1 the ,mediterranean1 and ,africa1 and even ,japan and the east coast of ,asia4 ,as far south as ,zanzibar1 ,mozambique1 and ,natal disturbances were also noticed4 ,they were in ,europe most intense on the morning of ,august #ab1 when they lasted the whole day1 and increased again in intensity toward eight o'clock in the evening1 while they suddenly ceased everywhere almost simultaneously4 ,scientific and careful observations were only taken at a few places1 but the existence of earth currents in frequently changing direction and varying intensity1 was noticed everywhere4 ,long lines of wires were more affected than short ones1 and although some lines--for instance the ,berlin-,hamburg in an east-west direction--were not at all influenced1 no general law was noticed according to which certain directions were freed from the disturbing influence4 ,while1 for instance1 the ,red ,sea cable was not noticeably affected1 the land line to ,bombay1 forming a continuation of this cable1 was materially disturbed4 ,the ,marseilles-,algiers cable1 so seriously influenced in #ahga1 showed no signs at all1 but as may be expected1 the north of ,europe suffered more than the south1 and in ,nystad1 ,finland1 the galvanometer indicated an intensity of current equal to that of #bjj ,leclanch cells4 ,since thunderstorms are generally local1 it is only natural that their effect upon telegraph cables should also be confined to one locality4 ,numerous careful observations1 carried out over considerable periods of time1 show that the disturbing influences of thunderstorms on telegraph lines are of less duration and more varying in direction and intensity than those of the aurora borealis4 ,long lines suffer less than short lines2 telegraph wires above ground are more easily and more intensely affected than underground cables4 ,it is1 however1 possible1 that this is mainly due to the fact that in the districts where strict records were kept1 in the ,german ,empire1 most of the long lines are underground cables1 while most of the short local lines are overground wires4 ,the results of the disturbances varied2 in ,hughes's apparatus the armatures were thrown off1 lines in operation indicated wrong signs1 dots became dashes1 and the spaces were either multiplied in size or number1 according to the direction of the earth currents induced by the thunderstorms4 ,since these observations extended over nearly #b1jjj cases1 some conclusions might fairly be drawn from them4 ,for the purpose of a more complete knowledge on this subject1 ,dr4 ,wykander recommends a series of regular observations on earth currents to be carried out at different stations1 well distributed over the whole surface of the globe1 these observations to be made between six and eight ,a4,m41 and at the same time in the evening4 ,special arrangements to be made at various stations to record exceptionally intense disturbances during the phenomena of the aurora borealis1 notice to be taken of time1 direction1 intensity1 and all further particulars4 ,since this question appears to bear a considerable amount of influence on underground cables1 it is one that deserves serious attention before earth cables are more generally introduced2 there can1 however1 be little doubt that they are not nearly so much exposed as overhead wires to disturbing influences of other kinds1 such as snow1 rain1 wind1 etc41 while they certainly do suffer1 though perhaps in a less degree1 by electrical disturbances4--,engineering4 99 99 99 99 99 ,,the ,,photographic ,,image3 ,,what ,,it ,,is4 ,footnote3 ,a communication to the ,sheffield ,photographic ,society in the ,british ,journal of ,photography4 ,it is quite possible that in the remarks ,i propose making this evening in connection with the photographic art ,i may mention topics and some details which are familiar to many present2 but as chemistry and optical and physical phenomena enter largely into the theory and practice of photography1 the field is so extensive there is always something interesting and suggestive even in the rudiments1 especially to those who are commencing their studies4 ,although this paper may be considered an introductory one1 ,i do not wish to load it with any historical account1 or describe the early methods of producing a light picture1 but shall at once take for my subject1 ,the ,photographic ,image3 ,what ,it ,is1 and under this heading ,i must restrict myself to the collodion and silver or wet process1 leaving gelatine dry plates1 collodio-chloride1 platinum1 carbontype1 and the numerous other types which are springing up in all directions for future consideration4 ,now1 in an ordinary pencil1 pen and ink1 or sepia sketch we have a deposit of a dark1 non-reflecting substance1 which gives the outline of a figure on a lighter background4 ,the different gradations of shade are acquired by a more or less deposit of lead1 ink1 or sepia4 ,in photography--at least in the ordinary silver process--the image is formed by a deposition of metallic silver or organic oxide in a minute state of division1 either on glass1 paper1 or other suitable material4 ,this is brought about by the action of light and certain reagents4 ,light has long been recognized as a motive power comparable with heat or electricity4 ,its action upon the skin1 fading of colors1 and effect on the growth of vegetable and animal organisms are well known2 and1 although the exact molecular change in many instances is not clearly understood1 yet certain salts of silver1 iron1 the alkaline bichromates1 and some organic materials--as bitumen and gelatine--have been pretty well worked out4 ,it is a remarkable and well-known fact that the chloride1 iodide1 and bromide of silver--called sensitive salts in photography--are not susceptible 7at least only slowly7 to change when exposed to the yellow1 orange1 and red rays4 ,the longer wave lengths of the spectrum1 as you know1 form1 with violet1 indigo1 blue1 and green1 white light4 ,the diagram on the wall shows this dispersion and separation of the primitive colors4 ,these--the yellow1 orange1 and red-- are called technically non actinic rays1 and the others in their order become more actinic until the ultra violet is reached4 ,the action of white light1 or rays1 excluding yellow1 orange1 and red1 has the effect of converting silver chloride into a sub-chloride2 it drives off one equivalent of chlorine4 ,thus1 silver chloride1 ,ag#b;,cl#b;,ag#b;,cl,cl4 ,when water is present the water is decomposed4 ,hydrochloric acid1 ,h,cl1 hypochlorous acid1 ,h,cl,o is formed4 ,the iodide of silver in like manner is changed into a sub-iodide2 but with water hydriodic acid is formed unless an iodine absorbent be present--then into hypoiodic acid4 ,the silver bromide undergoes a similar change4 ,when with light alone1 a sub-bromide1 ,ag#b;,br#b;,ag#b;,br,br1 and with water hypobromous acid4 ,it is important to bear this in mind1 as one or other1 and frequently both iodide and bromide of silver1 is the sensitive salt requisite or used in producing the invisible image4 ,the theory regarding these sensitive salts of silver is that1 being very unstable1 i4 e41 ready to undergo a molecular change1 the undulations produced in the ether1 which pervades all space1 and the potential action or moving power of light is sufficient to disturb their normal chemical composition2 it liberates some of the chlorine1 iodine1 or bromine1 as the case may be4 ,this action1 of course1 applies to light from any source--the sun1 electricity1 or the brighter hydrocarbons1 also flame from gas or candle1 whether it comes direct as rays of white light or is reflected from an object and conducted through a lens as a distinct image upon the screen of a camera4 ,i have no time to speak on the subject of lenses1 only just to mention that they are1 or ought to be1 achromatic1 so as to transmit white light and of perfect definition1 and the amount of light passed through should be as much as possible consistent with a sharp image--at least when rapid exposure is attempted4 ,i shall touch very lightly on the manipulative part of photography1 as that would be unnecessary2 but a brief account of the chemicals in use is essential to a right appreciation of the theory of developing the image4 ,in the first place1 our object is to get a film of some suitable material coated with a thin layer of a sensitive salt of silver--say a bromo-iodide4 ,by mixing certain proportions of ammonium iodide and cadmium bromide1 or an iodide and bromide of cadmium with collodion--which is pyroxyline1 a kind of gun-cotton dissolved in ether and alcohol--a plate of glass is coated1 and before being perfectly dry is immersed in the nitrate of silver bath4 ,the silver nitrate solution1 adhering and entering to a slight extent the surface of the collodion1 becomes converted by an ordinary chemical action of affinity into silver iodide and bromide4 ,the ammonium and cadmium play a secondary part in the process1 and are not absolutely necessary in forming the image4 ,the plate is now extremely sensitive to light4 ,when we have entered it into the dark slide and camera1 and then exposed to light1 the change ,i mentioned has taken place4 ,the film is transformed into different quantities of sub-iodide and sub-bromide of silver1 according to brilliancy of light4 ,in addition1 there is on the plate an amount of unchanged silver nitrate which becomes useful in the second stage1 or development4 ,the image is not seen as yet1 being latent1 and requiring the well-known developing solution of sulphate of iron1 acetic acid1 alcohol1 and water4 ,practically we all recognize the effect of a nicely-balanced wave of developer worked round a plate4 ,the high lights are first to appear as a darker color1 till the details of shadow come out2 when this is reached the developer is washed off4 ,the chemical action is briefly thus1 and it can be shown by solutions without a photographic plate1 as in a test tube3 ,pour into this glass a solution of silver nitrate1 ,ag,n,o1 and add a solution of ferrous sulphate1 ,fe,s,o#d4 ,the ferrous sulphate combines with the nitric acid1 forming two new salts--ferric nitrate and ferric sulphate4 ,the silver is deposited4 ,any other substance which will remove oxygen from silver nitrate without combining with the silver would do the same1 and metallic silver would be thrown down4 ,the formula1 as shown on the diagram1 explains the interchange4 ,when the developer is poured over the plate it attacks first the free silver nitrate1 and causes it to deposit extremely fine particles of metallic silver4 ,the question arises3 ,how is it these particles arrange themselves to form an image8 ,this is explained by the physical movement known as molecular attraction or affinity4 ,these particles are attracted first to the portions of the plate where there is most sub-iodide and sub-bromide4 ,in the shady parts less silver is deposited4 ,when the image is once started it follows that particles of silver produced by the iron developer will cause more to fall down on the face of those already present1 and the image is1 of course1 built up if the silver nitrate be all consumed on the plate4 ,the developer then becomes useless or injurious4 ,the presence of acetic acid checks the reduction of the silver1 and the alcohol facilitates the flow when the bath becomes charged with ether and spirit4 ,the molecular attraction just mentioned is made plainer by reference to the simple lead tree experiment4 ,we have here in this bottle a piece of zinc rod introduced into a solution of acetate of lead4 ,a chemical change has taken place4 ,the zinc has abstracted the acetic acid and the lead is deposited on the zinc1 and will continue to be so until the solution is exhausted4 ,the irregularities of surface and arborescent appearance are well shown4 ,if the change were rapidly conducted the lead particles would from their weight sink directly to the bottom instead of aggregating together like ordinary crystals4 ,i have constructed a diagram of colored card1 which will perhaps more clearly demonstrate the relation of the different constituents4 ,the lower portion 7,fig4 a7 represents a section of the glass plate or support1 the collodion film 7,fig4 b7 having upon its surface a thin layer of bromo-iodine silver 7,fig4 c71 which1 when exposed to a well-lighted image1 as in a camera1 changes into different gradations of sub-bromide and sub-iodide1 as indicated by irregular1 dark masses in the film4 ,the dotted marks immediately above these are intended for the silver deposit 7,fig4 d7--clusters of granules1 more abundant in the well lighted and less in the shaded parts of the picture1 corresponding to the amount of sub-bromide and iodide beneath4 ,illustration3 ,,section ,,of ,,sensitive ,,plate ,,after ,,exposure ,,and ,,during ,,development4 d ,silver deposit--,image1 c ,sub-bromide and sub-chloride 7gradations of71 b ,collodion film--,substratum1 a ,section of glass plate--,support4 ,the next point to consider is that of intensification--a process seldom required in positive pictures1 and would not be needed so often in negatives if there was enough free silver nitrate on the plate during development4 ,the object1 as we all know1 in a wet-plate negative is to get good printing density without destruction of half-tone4 ,it is a rule1 ,i believe1 in an over-exposed picture to intensify after fixing the image1 and in an under-exposed picture to intensify before fixing4 ,whichever is done the intention is similar1 namely1 to intercept in a greater degree the light passing through a negative1 so as to make a whiter and cleaner print4 ,the usual intensifier--and1 ,i suppose1 there is no better--is pyrogallic acid1 citric acid1 water1 and a few drops of silver nitrate solution4 ,pyrogallic is the most active agent1 and might be used alone with water2 but for special reasons it is not desirable4 ,as a chemical it has a great affinity for oxygen1 and will precipitate silver from a solution containing1 for instance1 nitrate of silver4 ,it also combines with the metal1 forming a pyrogallate--a dark brown1 very non-actinic material4 ,the use of a few drops of ,ag,n,o#c solution is very evident4 ,a deposit is added to the image already formed4 ,citric acid is the retarder in this case4 ,alcohol is unnecessary1 as the film is well washed with water before the intensifier is used1 consequently it flows readily over the plate4 ,as regards fixing1 or1 more properly1 clearing the image3 it is the simple act of dissolving out or from the film all free nitrate1 chloride1 iodide1 or bromide4 ,cyanide of potassium does not attack the metallic deposit unless very strong4 ,it has then a tendency to reduce the detail in the shadows4 ,,thomas ,h4 ,,morton1 ,m4,d4 99 99 99 99 99 ,,gelatine ,,transparencies ,,for ,,the ,,lantern4 ,footnote3 ,a communication to the ,photographic ,society of ,ireland4 ,few of those who work with gelatine dry plates seem to be aware of the great beauty of the transparencies for lantern or other uses which can be made from them by ferrous oxalate development with the greatest ease and certainty4 ,i think this a very great pity1 for ,i hold the opinion that the lantern furnishes the most enjoyable and1 in some cases1 the most perfect of all means of showing good photographic pictures4 ,many prints from excellent negatives which may be passed over in an album without provoking a remark will1 if printed as transparencies and thrown on the screen1 call forth expressions of the warmest admiration2 and justly so1 for no paper print can do that full justice to a really good negative which a transparency does4 ,this difference is more conspicuous in these days of dry gelatine plates and handy photographic apparatus1 when many of our most interesting negatives are taken on quarter or #e x #d plates the small size of which frequently involves a crowding of detail1 much of which will be invisible in a paper print1 but which1 when unraveled or opened out1 as it were1 by means of the lantern1 enhances the beauty of the pictures immensely4 ,when ,i last had the pleasure of bringing this subject before the members of our society1 it may be remembered that ,i demonstrated the ease and simplicity with which those beautiful results maybe obtained1 by printing in an ordinary printing frame by the light of my petroleum developing lamp1 raising one of its panes of ruby glass for the purpose for five seconds1 and then developing by ferrous oxalate until ,i got the amount of intensity requisite4 ,on that evening1 in the course of a very just criticism by one of our members1 ,mr4 ,j4 ,v4 ,robinson1 he pointed out what was undoubtedly a defect1 viz41 a slightly opalescent veiling of the high lights1 which should range from absolutely bare glass in the highest points4 ,he showed that1 in consequence of this veiling1 the light was sensibly diminished all over the picture4 ,this veiling of the high lights was a serious disadvantage in another important particular1 inasmuch as it lessened the contrast between the lights and shadows of the picture1 thereby robbing it of some of its charm and deteriorating its quality4 ,since that evening ,i have endeavored1 by a series of experiments1 to find out some means by which this opalescence might be got rid of in the most convenient manner4 ,cementing the transparency to a piece of plain1 clear glass with ,canada balsam1 as suggested by ,mr4 ,woodworth1 ,i found in practice to be open to two formidable objections4 ,one of these was that ,canada balsam used in this manner is a sticky1 unpleasant substance to meddle with1 and takes a long time--nearly a month--to harden when confined between plates in this manner4 ,the other objection was of extreme importance1 namely1 that1 in consequence of commercial gelatine plates not being prepared on perfectly flat glasses in all cases1 ,i found that1 after squeezing out the superfluous balsam and the air bubbles that might have formed from between the two plates1 they are liable to separate at the places where the transparency is not flat1 causing air bubbles to creep in from the edges1 as you may see from these examples4 ,i1 therefore1 have discarded this method1 although it had the effect desired when successfully done4 ,i have hit1 however1 upon another way of utilizing ,canada balsam1 which1 while retaining all the good qualities of the former method1 is not subject to any of its disadvantages4 ,this consists in diluting the balsam with an equal bulk of turpentine1 and using it as a varnish1 pouring it on like collodion1 flowing it toward each corner1 and pouring it off into the bottle from the last corner1 avoiding crapy lines by slowly tilting the plate1 as in varnishing4 ,if the plate be warmed previously1 the varnish flows more freely and leaves a thinner coating of balsam behind on the transparency4 ,when the plate has ceased to drip1 place it in a plate drainer1 with the corner you poured from lowest1 and leave it where dust cannot get at it for four or five days1 when it will be found sufficiently hard to be put into a plate box4 ,the transparency may be finished at any time afterward by putting a clean glass of the same size along with it1 placing one of the blank paper masks sold for the purpose--either circular or cushion-shaped to suit the subject--between the plates1 and pasting narrow strips of thin black paper over the edges to bind them together4 ,this method is very successful1 as you may see from the examples4 ,it renders the high lights perfectly clear1 and leaves a film like glass over all the parts of the transparency where the varnish has flowed4 ,in order to avoid the risk of dust involved in this process1 ,i tried other means of arriving at similar results and with success1 for the plates ,i now submit to you have been simply rubbed or polished1 as ,i may say1 with a mixture of one part of ,canada balsam to three parts of turpentine1 using either a small tuft of ,french wadding or a small piece of soft rag for the purpose1 continuing the rubbing until the plate is polished nearly dry4 ,this method is particularly successful1 rendering the clear parts of the sky like bare glass4 ,i have here a plate which is heavily veiled--almost fogged1 in fact--one half of which ,i have treated in this way1 showing that the half so treated is beautifully clear1 while the other half is so veiled as to be apparently useless4 ,i have tried to still further simplify this necessary clearing of those plates1 and find that soaking tor twelve hours in a saturated solution of alum1 after washing the hypo out of the plate1 is successful in a large number of cases2 and where it is successful there is no further trouble with the transparency1 except to mount it after it becomes dry4 ,where it is not entirely successful ,i put the plate into a solution of citric acid1 four ounces to a pint of water1 for about one minute1 and have in nearly all cases succeeded in getting a beautifully-clear plate4 ,the picture must not be left long in the citric acid solution1 or it will float off2 neither do ,i like using citric acid until after trying the alum1 for a similar reason4 ,i may mention that ,i recommend a short exposure in the printing-frame and slow development1 in order to get sufficient intensity4 ,of course the exposure is always made to a gas or petroleum light4 ,i also still prefer the old method of making the ferrous oxalate solution1 pouring it back into the bottle each time after using1 and using it for two or three months1 keeping the bottle full from a stock bottle1 and occasionally putting a little dry ferrous oxalate into the bottle and shaking it up1 allowing it to settle before using next time4 ,by treating it in this way it retains its power fairly well for a long time2 and as it becomes less active ,i give a little longer exposure1 balancing one against the other4 ,making the ferrous oxalate solution from two saturated solutions of iron sulphate and potassium oxalate has not succeeded so well with me for transparencies4 ,the tone of the picture is not so black as when developed by the old method2 and ,i do not like gray transparencies for the lantern4 ,i also recommend very slow gelatine plates1 about twice as sensitive as wet collodion--not more1 if ,i can help it4 ,i have demonstrated1 ,i hope to your satisfaction1 the possibility of producing lantern slides from commercial gelatine plates of a most beautiful quality--ranging from clear glass to deep black1 and giving charming gradation of tones1 showing on the screen a film as structureless as albumen slides1 without the great trouble involved in making them4 ,you must not accept the slides put before you this evening as the best that can be done with gelatine4 ,far from it2 they are only the work of an amateur with very little leisure now to devote to their manufacture1 and are merely the result of a series of experiments which1 so far as they have gone1 ,i now place before you4--,thomas ,mayne1 ,t4 ,c41 in ,british ,journal of ,photography4 99 99 99 99 99 ,,an ,,integrating ,,machine4 ,footnote3 ,read at a meeting of the ,physical ,society1 ,feb4 #bf4 ,by ,c4,v4 ,,boys4 ,all the integrating machines hitherto made1 of which ,i can find any record1 may be classed under two heads1 one of which1 ,ainslee's machine1 is the sole representative1 depending on the revolution of a disk which partly rolls and partly slides on the paper1 and the other comprising all the remaining machines depending on the varying diameters of the parts of a rolling system4 ,now1 none of these machines do their work by the method of the mathematician1 but in their own way4 ,my machine1 however1 is an exact mechanical translation of the mathematical method of integrating y dx1 and thus forms a third type of instrument4 ,the mathematical rule may be described in words as follows3 ,required the area between a curve1 the axis of x and two ordinates2 it is necessary to draw a new curve1 such that its steepness1 as measured by the tangent of the inclination1 may be proportional to the ordinate of the given curve for the same value of x1 then the ascent made by the new curve in passing from one ordinate to the other is a measure of the area required4 ,the figure shows a plan and side elevation of a model of the instrument1 made merely to test the idea1 and the arrangement of the details is not altogether convenient4 ,the frame-work is a kind of ,t square1 carrying a fixed center1 ,b1 which moves along the axis of x of the given curve1 a rod passing always through ,b carries a pointer1 ,a1 which is constrained to move in the vertical line1 ee1 of the ,t square1 ,a then may be made to follow any given curve4 ,the distance of ,b from the edge1 ee1 is constant2 call it ,k1 therefore1 the inclination of the rod1 ,,ab1 is such that its tangent is equal to the ordinate of the given curve divided by ,k2 that is1 the tangent of the inclination is proportional to the ordinate2 therefore1 as the instrument is moved over the paper1 ,,ab has always the inclination of the desired curve4 ,the part of the instrument that draws the curve is a three-wheeled cart of lead1 whose front wheel1 ,f1 is mounted1 not as a caster1 but like the steering wheel of a bicycle4 ,when such a cart is moved1 the front wheel1 ,f1 can only move in the direction of its own plane1 whatever be the position of the cart2 if1 therefore1 the cart is so moved that ,f is in the line1 ee1 and at the same time has its plane parallel to the rod1 ,,ab1 then ,f must necessarily describe the required curve1 and if it is made to pass over a sheet of black tracing paper1 the required curve will be drawn4 ,the upper end of the ,t square is raised above the paper1 and forms a bridge1 under which the cart travels4 ,there is a longitudinal slot in this bridge in which lies a horizontal wheel1 carried by that part of the cart corresponding to the head of a bicycle4 ,by this means the horizontal motion communicated to the front wheel of the cart by the bridge1 is equal to that of the pointer1 ,a2 at the same time the cart is free to move vertically4 ,the mechanism employed to keep the plane of the front wheel of the cart parallel to ,,ab is made clear by the figure4 ,three equal wheels at the ends of two jointed arms are connected by an open band1 as shown4 ,now1 in an arrangement of this kind1 however the arms or the wheels are turned1 lines on the wheels1 if ever parallel1 will always be so4 ,if1 therefore1 the wheel at one end is so supported that its rotation is equal to that of ,,ab1 while the wheel at the other end is carried by the fork which supports ,f1 then the plane of ,f1 if ever parallel to ,,ab1 will always be so4 ,therefore1 when ,a is made to trace any given curve1 ,f will draw a curve whose ascent is 7#a_/,k7 f y dx1 and this1 multiplied by ,k1 is the area required4 ,illustration3 ,,an ,,integrating ,,machine4 ,not only does the machine integrate y dx1 but if the plane of the front wheel of the cart is set at right angles instead of parallel to ,,ab1 then the cart finds the integral of dx _/ y1 and thus solves problems1 such1 for instance1 as the time occupied by a body in moving along a path when the law of the velocity is known4 ,some modifications of the machine already described will enable it to integrate squares1 cubes1 or products of functions1 or the reciprocals of any of these4 ,of the various curves exhibited which have been drawn by the machine1 the following are of special physical interest4 ,given the inclined straight line y cx1 the machine draws the parabola y cx _/ #b4 ,this is the path of a projectile1 as the space fallen is as the area of the triangle between the inclined line1 the axis of x1 and the traveling ordinate4 ,given the curve representing attraction y #a _/ x the machine draws the hyperbola y #a _/ x the curve representing potential1 as the work done in bringing a unit from an infinite distance to a point is measured by the area between the curve of attraction1 the axis of x1 and the ordinate at that point4 ,given the logarithmic curve y ex1 the machine draws an identical curve4 ,the vertical distance between these two curves1 therefore1 is constant2 if1 then1 the head of the cart and the pointer1 ,a1 are connected by a link1 this is the only curve they can draw4 ,this motion is very interesting1 for the cart pulls the pointer and the pointer directs the cart1 and between they calculate a table of ,naperian logarithms4 ,given a wave-line1 the machine draws another wave-line a quarter of a wave-length behind the first in point of time4 ,if the first line represents the varying strengths of an induced electrical current1 the second shows the nature of the primary that would produce such a current4 ,given any closed curve1 the machine will find its area4 ,it thus answers the same purpose as ,ainslee's polar planimeter1 and though not so handy1 is free from the defect due to the sliding of the integrating wheel on the paper4 ,the rules connected with maxima and minima and points of inflexion are illustrated by the machine1 for the cart cannot be made to describe a maximum or a minimum unless the pointer1 ,a1 crosses the axis of x1 or a point of inflexion unless ,a passes a maximum or minimum4 99 99 99 99 99 ,,upon ,a ,,modification ,,of ,,wheatstone',s ,,microphone ,,and ,,its ,,applicability ,,to ,,radiophonic ,,researches4 ,footnote3 ,a paper read before the ,philosophical ,society of ,washington4 ,d4 ,c41 ,june #aa1 #ahha4 ,by ,,alexander ,,graham ,,bell4 ,in ,august1 #ahhj1 ,i directed attention to the fact that thin disks or diaphragms of various materials become sonorous when exposed to the action of an intermittent beam of sunlight1 and ,i stated my belief that the sounds were due to molecular disturbances produced in the substance composing the diaphragm4#a ,shortly afterwards ,lord ,raleigh undertook a mathematical investigation of the subject and came to the conclusion that the audible effects were caused by the bending of the plates under unequal heating4#b ,this explanation has recently been called in question by ,mr4 ,preece1#c who has expressed the opinion that although vibrations may be produced in the disks by the action of the intermittent beam1 such vibrations are not the cause of the sonorous effects observed4 ,according to him the aerial disturbances that produce the sound arise spontaneously in the air itself by sudden expansion due to heat communicated from the diaphragm--every increase of heat giving rise to a fresh pulse of air4 ,mr4 ,preece was led to discard the theoretical explanation of ,lord ,raleigh on account of the failure of experiments undertaken to test the theory4 ,footnote #a3 ,amer4 ,asso4 for ,advancement of ,science1 ,august #bg1 #ahhj4 ,footnote #b3 ,nature1 vol4 xxiii41 p4 #bgd4 ,footnote #c3 ,roy4 ,soc41 ,mar4 #aj1 #ahha4 ,illustration3 ,fig4 #a4 ,a ,b1 ,carbon ,supports4 ,c1 ,diaphragm4 ,he was thus forced1 by the supposed insufficiency of the explanation1 to seek in some other direction the cause of the phenomenon observed1 and as a consequence he adopted the ingenious hypothesis alluded to above4 ,but the experiments which had proved unsuccessful in the hands of ,mr4 ,preece were perfectly successful when repeated in ,america under better conditions of experiment1 and the supposed necessity for another hypothesis at once vanished4 ,i have shown in a recent paper read before the ,national ,academy of ,science1#a that audible sounds result from the expansion and contraction of the material exposed to the beam1 and that a real to-and-fro vibration of the diaphragm occurs capable of producing sonorous effects4 ,it has occurred to me that ,mr4 ,preece's failure to detect1 with a delicate microphone1 the sonorous vibrations that were so easily observed in our experiments1 might be explained upon the supposition that he had employed the ordinary form of ,hughes's microphone shown in ,fig4 #a1 and that the vibrating area was confined to the central portion of the disk4 ,under such circumstances it might easily happen that both the supports 7a b7 of the microphone might touch portions of the diaphragm which were practically at rest4 ,it would of course be interesting to ascertain whether any such localization of the vibration as that supposed really occurred1 and ,i have great pleasure in showing to you tonight the apparatus by means of which this point has been investigated 7see ,fig4 #b74 ,footnote #a3 ,april #ba1 #ahha4 ,illustration3 ,fig4 #b4 ,a1 ,stiff wire4 ,b1 ,diaphragm4 ,c1 ,hearing tube4 ,d1 ,perforated handle4 ,the instrument is a modification of the form of microphone devised in #ahgb by the late ,sir ,charles ,wheatstone1 and it consists essentially of a stiff wire1 ,a1 one end of which is rigidly attached to the center of a metallic diaphragm1 ,b4 ,in ,wheatstone's original arrangement the diaphragm was placed directly against the ear1 and the free extremity of the wire was rested against some sounding body--like a watch4 ,in the present arrangement the diaphragm is clamped at the circumference like a telephone diaphragm1 and the sounds are conveyed to the ear through a rubber hearing tube1 c4 ,the wire passes through the perforated handle1 ,d1 and is exposed only at the extremity4 ,when the point1 ,a1 was rested against the center of a diaphragm upon which was focused an intermittent beam of sunlight1 a clear musical tone was perceived by applying the ear to the hearing tube1 c4 ,the surface of the diaphragm was then explored with the point of the microphone1 and sounds were obtained in all parts of the illuminated area and in the corresponding area on the other side of the diaphragm4 ,outside of this area on both sides of the diaphragm the sounds became weaker and weaker1 until1 at a certain distance from the center1 they could no longer be perceived4 ,at the point where we would naturally place the supports of a ,hughes microphone 7see ,fig4 #a7 no sound was observed4 ,we were also unable to detect any audible effects when thepoint of the microphone was rested against the support to which the diaphragm was attached4 ,the negative results obtained in ,europe by ,mr4 ,preece may1 therefore1 be reconciled with the positive results obtained in ,america by ,mr4 ,tainter and myself4 ,a still more curious demonstration of localization of vibration occurred in the case of a large metallic mass4 ,an intermittent beam of sunlight was focused upon a brass weight 7#a kilogramme71 and the surface of the weight was then explored with the microphone shown in ,fig4 #b4 ,a feeble but distinct sound was heard upon touching the surface within the illuminated area and for a short distance outside1 but not in other parts4 ,in this experiment1 as in the case of the thin diaphragm1 absolute contact between the point of the microphone and the surface explored was necessary in order to obtain audible effects4 ,now ,i do not mean to deny that sound waves may be originated in the manner suggested by ,mr4 ,preece1 but ,i think that our experiments have demonstrated that the kind of action described by ,lord ,raleigh actually occurs1 and that it is sufficient to account for the audible effects observed4 99 99 99 99 99 ,a catalogue1 containing brief notices of many important 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