,transcriber's ,notes3 ,illustration has been moved so it does not break up the paragraph4 ,as this was a hand-written thesis1 the spelling1 punctuation and hyphenation is very inconsistent4 ,the original spelling1 hyphenation and punctuation have been left unchanged4 ,subscripts appears as ,x where ,x is an integer4 ,multi-line curly brackets have been replaced with multi-line square brackets4 ,,on ,,sulphonfluoresce,n ,,and ,,some ,,of ,,its ,,derivatives4 ,,dissertation ,presented for the ,degree of ,doctor of ,philosophy at the ,johns ,hopkins ,university by ,c4 ,willard ,hayes1 #ahhg4 ,contents4 p4 ,introduction #c4 ,i ,ortho-sulpho-benzoic acid4 ,preparation from toluene and ,h#b,,so#d #g4 0 0 para-nitro-toluene and ,h#b,,so#d #h4 ,oxidation of toluene-o-sodium sulphonate #ab4 ,preparation of ,sulphinide from 0 0 #ad4 0 0 0 by chlorsulphonic acid4 #ag4 ,conversion of sulphinide into o-sulphobenzoic acid4 #be4 ,analysis of and crystallography of 0 0 0 #bh4 ,,ii ,sulphonfluorescen--previous attempts #bi4 ,preparation and purification of s-fluorescen #cj4 ,analyses of 0 #cd4 ,properties of 0 #ce4 ,salts4 ,ba4 and ,ca4 of 0 #cg4 ,acetyl derivative of 0 #da4 ,br substitution products of 0 #db4 ,action of ,h#b,,so#d on 0 #dd4 ,action of ,h,cl on 0 #de4 ,reduction of 0 #df4 ,conclusion4 #dg4 ,on ,sulphonfluorescen and some of its ,derivatives4 ,introduction4 ,the close analogy in composition and structure between phthalic acid and ortho-sulpho-benzoic acid suggests the possibility of obtaining from the latter1 by its action on phenols1 substances analogous to the phthalens4 ,if such compounds could be made they would afford a favorable opportunity of studying the effects produced in the properties of a compound by the replacement of ,,co by ,,so#b4 ,it was with a view to such study that the following discussed work was undertaken at the suggestion of ,prof4 ,remsen and carried on under his constant guidance4 ,some experiments previously performed by ,remsen and ,palmer 7,a4,g47 indicated the possibility of the formation of a fluorescent substance by the action of ortho-sulpho-benzoic acid on resorcin but they did not succeed in obtaining any definite crystallized compound from the reaction4 ,the chief obstacle to be overcome in the work is the difficulty in obtaining the o-sulpho-benzoic acid and a large proportion of the work here described was applied in that direction4 ,ortho-sulpho-benzoic acid3 ,methods for its preparation4 #a4 ,from toluene and ,h#b,,so#d4 ,a method employed by ,remsen and ,fahlberg 7,am4 ,ch4 ,jour4 ,vol4 #a4 p 7 for getting the sulphonic acid group in the ortho position to methyl was2 7a7 treat toluene with fuming ,h#b,,so#d forming thus ortho- and para- toluene sulphonic acids1 7b7 make the calcium salt of the sulphonic acids thus formed and from this the potassium salt4 7c7 treat this mixture of potassium toluene sulphonates with phosphorous penta-chloride forming the corresponding sulphonchlorides4 ,one of these 7para7 being a solid and the other 7ortho7 an oily liquid a nearly complete separation could be effected4 ,the difficulty with this method is however that the larger part of the product is the para and only a comparatively small proportion of the ortho compound is formed4 #b4 ,from p-nitro-toluene and ,h#b,,so#d4 ,a second method employed consists in starting with p-nitro-toluene4 ,this when treated with ,h#b,,so#d forms toluene p-nitro o-sulphonic acid4 ,if now a method could be obtained for removing the nitro group the desired result would be attained4 ,the attempt was made by ,remsen and ,palmer 7,a4,g47 to accomplish this by 7a7 reducing the nitro compound to the amide1 7b7 making the diazo compound and 7c7 boiling this with absolute alcohol4 ,according to generally accepted views this should effect the removal of the diazo group and its replacement by hydrogen4 ,experiments however showed that the replacement was made not by hydrogen but by the ethoxy group -,,oc#b;,h#e4 ,this method was therefore impracticable4 ,a modification of this method was suggested by an observation of ,baeyer and ,liebermann that if phenyl hydrazine be boiled with a dilute solution of copper sulphate the hydrazine group is replaced by hydrogen and benzene thus formed4 ,hence it was believed that if the hydrazine compound should be made from diazo compound mentioned above1 the corresponding hydrocarbon1 i4e4 toluene o-sulphonic acid could be obtained4 ,the results of experiments showed that this afforded a practicable method of preparing toluene ortho-sulphonic acid4 ,after experimenting with various modifications of the method the following was found to be the best adapted to the purpose4 ,the potassium salt of toluene p-nitro-o-sulphonic acid is easily obtained1 as already stated1 by heating p-nitro toluene on the water bath with three times its weight of fuming ,h#b,,so#d1 neutralizing with chalk and to the solution of calcium salt thus obtained adding a slight excess of ,k#b;,,co#c4 ,on filtering from4 the precipitated ,ca,c,o#c and evaporating slightly1 the salt is obtained in long needle shaped crystals of a pale straw yellow color4 ,this is ,,ch#c ,c#f;,h#c,,so#b,,oh 7o7 ,,no#b 7p74 ,the reduction of the nitro group is best effected by means of tin and ,h,cl1 in the proportion1 salt #e parts1 tin #f parts and concentrated ,h,cl #cj parts4 ,the amido acid forms a compound with tin which crystallizes from the ,h,cl together with stannous chloride4 ,this compound may be broken up and the tin removed by continued boiling with water4 ,a better method of removing the tin is by dissolving the compound in ,na#b;,,co#c4 ,this forms a salt with the amido acid and throws down the tin as ,sn7,,oh7#b1 a white flocculent precipitate4 ,on filtering and adding to the solution conc4 ,h,cl1 the free amido acid is deposited in characteristic colorless1 rhombic crystals1 having the formula ,,ch#c ,c#f;,h#c,,so#b,,oh 7o7 ,,nh#b 7p7 ,the method at first employed for preparing the hydrazine compound consisted in treating the amido acid1 suspended in ,h,cl1 with potassium nitrite and then with stannous chloride4 ,the tin was then removed from the solution by the addition of sodium carbonate and the hydrazine compound thrown down with ,h,cl4 ,this method however gave poor results the yield being only about #ej of the theoretical4 ,another method was accordingly substituted for the above1 namely that of ,strecker and ,rmer 7,ber4 ,,iv4 s #ghd47 ,by this the diazo compound is made first and isolated4 ,this is done by suspending the finely powdered acid in absolute alcohol1 cooling and passing a current of the oxides of nitrogen through in the ordinary way4 ,the acid changes in appearance1 becoming more crystalline and slightly darker and settles quickly on being shaken4 ,the reaction here may be expressed thus-- ,,ch#c ,,ch#c ,c#f;,h#c ,,so#b,,oh ,,hno#b ,c#f;,h#c ,,so#c #b;,h#b,o ,,nh#b ,n,n ,when the reaction is completed as shown by the appearance of the suspended powder it is filtered and while still fresh is added to a solution of acid sodium sulphite as long as it continues to dissolve readily4 ,to this solution there is added a quantity of solution of acid sodium sulphite equivalent to that already used and the solution is then boiled4 ,it has at first a deep red color but in a few moments becomes light reddish yellow4 ,the reaction of ,h,na,s,o#c on the diazo compound may be represented in two stages1 the first portion forming an addition product and the second acting as a reducing agent4 ,thus1 ,,ch#c ,,ch#c #a4 ,c#f;,h#c ,,so#c ,h,na,s,o#c ,c#f;,h#c ,,so#b,o,na ,n,n ,n,,nso#c;,h ,,ch#c #b4 ,c#f;,h#c ,,so#b,o,na ,h,na,s,o#c ,h#b,o ,n,,nso#c;,h ,,ch#c ,c#f;,h#c ,,so#b,o,na ,h,na,s,o#d4 ,,nh-,,nhso#c;,h ,to the hot solution an excess of conc4 ,h,cl is added when the hydrazine compound separates in a few moments in lustrous yellow scales which completely fill the solution4 ,on the addition of the ,h,cl a large amount of ,,so#b is given off from the excess of ,h,na,s,o#c and the solution becomes deep red4 ,when the hydrazine has separated the mother liquor is again yellow4 ,the reaction is represented as follows3 ,,ch#c ,c#f;,h#f,,so#b,o,na ,h,cl ,h#b,o ,,nh-,,nhso#c;,h ,,ch#c ,c#f;,h#c,,so#b,,oh ,h#b,,so#d ,na,cl ,,nh-,,nh#b ,the yield of hydrazine when both the diazo and the ,na,h,s,o#c are freshly prepared is practically quantitative4 ,the hydrazine thus prepared was treated with a hot #aj solution of copper sulphate till a permanent blue color was obtained in the solution4 ,nitrogen is evolved and the copper sulphate is reduced to cuprous oxide which is precipitated as a red powder4 ,the reaction is as follows4 ,,ch#c ,c#f;,h#c,,so#b,,oh #b;,cu,s,o#d ,h#b,o ,,nh-,,nh#b ,c#f;,h#d;,,ch#c ,cu#b,o ,n#b #b;,h#b,,so#d ,,so#b,,oh ,chalk was added to the solution to precipitate the ,h#b,,so#d and form a calcium salt of toluene-o-sulphonic acid4 ,from this the sodium salt was made by adding a slight excess of ,na#b,,so#c and evaporating to dryness4 ,the salt is very soluble being deliquescent in the air while the corresponding potassium salt is not4 ,from #aech gr4 of para-nitro-toluene1 #fee gr4 of toluene ortho-sodium sulphonate were obtained4 ,having thus obtained the toluene ortho-sulphonic acid the next step in the problem was to find a convenient method for converting this into ortho-sulph-benzoic acid4 ,two ways present themselves for accomplishing this end4 7#a7 direct oxidation of this salt and 7#b7 conversion into benzoic sulphinide from which the acid may be obtained4 ,both of these methods were tried4 ,oxidation of toluene-o-sodium sulphonate4 ,c#f;,h#d;,,ch#c ,,so#b,o,na ,the sodium salt of toluene-o-sulphonic acid is oxidized to ortho-sulphobenzoic acid with considerable difficulty by ,k,mn,o#d in neutral solution4 ,thus two experiments showed that the oxidation was not complete after #bd hours boiling with excess of permanganate4 ,if the solution be made alkaline however1 the oxidation is completed in a few hours1 yet the greatest difficulty still remains in the separation of the free acid from the products of oxidation in the solution4 ,if ,h,cl be added to the solution the acid salt ,,cooh ,c#f;,h#d ,,so#b,,ok is formed and this has nearly the same solubility as the ,k,cl also present4 ,a better method therefore is to add a slight excess of ,h#b,,so#d and evaporate nearly to dryness4 ,in this way are formed sulphates and the free acid presumably4 ,the mixture is heated with alcohol 7#ie7 which extracts the acid leaving the greater part of the manganese salts4 ,this extract is evaporated and reextracted with alcohol4 ,to this solution ,ba,c,o#c is added to precipitate the ,h#b,,so#d and form the ,barium salt of the o-sulphobenzoic acid4 ,the solution is filtered from the ,ba,s,o#d and just enough ,h#b,,so#d is added to exactly precipitate the barium4 ,the solution should thus contain only the free acid sought1 which crystallizes out on evaporating to a small volume4 ,while the method is theoretically possible it presents so many difficulties that it is practically useless4 ,the yield is extremely small2 only enough acid being obtained in this way to show that it was possible4 ,formation of ,sulphinide from toluene-o-sodium sulphonate4 ,the second method for obtaining free o-sulphobenzoic acid from toluene-ortho-sulphonic acid is by the conversion of the latter first into benzoic sulphinide and then into the free acid4 ,the sulphinide was made essentially as described by ,remsen 7,am4 ,ch4 ,jour4 ,vol4 ,i4 p4 #dbh7 with a few changes in the details as follows4 ,the salt ,c#f;,h#d;,,ch#c finely pulverized and in portions ,,so#b,o,na of from #aj to #ej gr4 was placed in a ,florence flask2 an equivalent quantity of ,p,cl#e added2 ,an inverted condenser was then attached and the flask shaken4 ,the action takes place at once and involves sufficient heat to distill off the oxychloride formed in the reaction4 ,this being returned to the flask by the condenser furnishes a liquid medium in which the reaction takes place more readily and completely than when it is not present4 ,it is best to cool the flask at first and afterwards heat gently on the water bath4 ,the reaction which takes place may be represented as follows4 ,,ch#c ,,ch#c ,c#f;,h#d,,so#b,o,na ,p,cl#e ,c#f;,h#d,,so#b;,cl ,p,o,cl#c ,na,cl4 ,on the addition of water the chloride separates as a light yellow oil4 ,this is washed with water and concentrated aqueous ammonia added1 which forms toluene-o-sulphonamide thus4 ,,ch#c ,,ch#c ,c#f;,h#d ,,nh#c ,c#f;,h#d ,h,cl4 ,,so#b;,cl ,,so#b,,nh#b ,the reaction is accompanied by a slight evolution of heat and the formation1 apparently1 of an intermediate product having a yellowish color1 which passes over on longer standing into the white amide4 ,after standing several hours the excess of ammonia was driven off by very gentle heating on the water bath4 ,if the heat is too high a large amount of a tarry product is formed and the yield of amide is correspondingly small4 ,in any case some of this tarry product is formed4 ,when nearly all the ammonia had been driven off the mass was boiled with water which dissolves everything except the tar4 ,the hot solution was filtered through charcoal and on cooling the amide separated in white feathery crystals which melt at #aee-aef4 ,the amide thus obtained was oxidized as described by ,remsen 7loc4 cit47 with potassium permanganate in neutral solution4 ,the proportions are #aj gr amide4 #dj gr ,k,mn,o#d and #a ,l4 water4 ,the oxidation was usually effected in from four to six hours4 ,to obtain the sulphinide from this solution after oxidation1 the latter1 after filtration from the precipitated oxides of manganese1 was slightly acidified with ,h,cl and evaporated to about one fourth its original volume4 ,on the addition of concentrated ,h,cl to this solution1 the sulphinide separated out in white or slightly yellowish feather shaped crystals melting at #bab and having the characteristic intensely sweet taste4 ,formation of ,sulphinide from ,toluene by means of the chlorsulphonic acid reaction4 ,before passing on to the methods used for converting the sulphinide into free acid another method should be described by which the former was obtained in larger quantities and much more easily than by the one above described4 ,beckurts and ,otto 7,ber4 ,,xi4 #bjfa7 found that by treatment of toluene with sulphuryl hydroxy-chloride or chlorsulphonic acid1 ,cl,s,o#b,,oh1 both o- and p- and as they supposed also m-toluene sulphonchlorides were formed together with the corresponding sulphonic acid4 ,claesson and ,wallin 7,ber4 ,,xii4 p4 #ahdh7 repeated the work reaching practically the same results and finally ,noyes 7,am4 ,ch4 ,jour4 ,vol4 ,,viii4 p4 #agf7 employed the reaction as a convenient method for obtaining toluene o-sulphon-chloride4 ,chlorsulphonic acid is made by passing dry ,h,cl over solid sulphuric acid so long as it continues to be absorbed4 ,since no solid sulphuric acid was at hand1 ordinary fuming ,nordhausen acid was taken and from one of two equal portions the ,,so#c was driven over into the other4 ,h,cl was passed into the latter and the resulting chlorsulphonic acid distilled off at about #aef4 ,this was placed in a flask1 provided with a drop funnel and exit tube1 in portions of #aej gr4 and to each portion #fj gr4 of toluene was added1 very slowly1 with constant shaking1 the temperature being kept near #aj4 ,the action is violent and if any toluene is allowed to collect on the surface of the liquid it is apt to produce disastrous results4 ,large quantities of ,h,cl are given off and the liquid in the flask assumes a brown color4 ,when all the toluene has been added1 it is poured into a large quantity of ice water1 when the sulphon-chlorides separate out1 the ortho- as a heavy oil and the para- as a white crystalline solid4 ,after allowing to stand some time in order that as much of the para-chloride might crystallize as possible the ortho- was drawn off and subjected to a freezing temperature for several hours4 ,by this means more of the p-chloride was removed and the operation was replicated as long as any crystals continued to form1 generally two or three times4 ,in this way the greater part of the para- may be removed1 though some still remains dissolved in the liquid chloride1 which cannot be removed by repeated freezings4 ,the chloride thus obtained was treated with strong aqueous ammonia4 ,the conversion to the sulphamide does not take place so readily as in case of the pure o-chloride obtained from the sulphonic acid and phosphorus pentachloride4 ,after standing about two days the whole of the oily chloride had solidified to a yellowish brown mass4 ,the excess of ammonia was driven off by gentle heating on the water bath and the mass then boiled with water4 ,not enough water was added at first for complete solution but when the first portion was saturated it was poured off through a filter and from it the amide separated in yellowish feathery crystals which melted at #aje-abe and consisted therefore as shown by ,fahlberg 7,am4 ,ch4 ,jour4 ,vol4 ,i4 p4 #agj7 of a mixture of o- and p-sulphonamides4 ,it was recrystallized and from it was obtained a portion melting at #aec-e and one at #ajh-bj4 ,since this mixture cannot be completely separated by recrystallization another method was suggested4 ,remsen has shown that ,k#b;,cr#b,o#g in acid solution does not oxidize the methyl group in ,,ch#c ,c#f;,h#d ,,so#b,,nh#b 7o7 but does oxidize that in ,,ch#c ,c#f;,h#d ,,so#b,,nh#b 7p74 ,it was thought that in a mixture of the two the former might be left unchanged while the latter was oxidized to p-sulphamine benzoic acid4 ,to test this #ae gr of the mixture1 melting at #aje-abe1 was heated with #dj gr ,k#b;,cr#b,o#g1 #ee gr ,h#b,,so#d and #b vols4 of water for about two hours4 ,it was then tested and shown to be still a mixture of p- o-amides1 since it was again heated for several hours with half the original quantity of oxidizing mixture1 then diluted1 filtered and washed4 ,the white crystalline residue was treated with sodium carbonate to dissolve the benzoic para-sulphamide and the residue was found to be pure toluene o-sulphonamide melting at #aec-aee4 ,the small quantity remaining1 #c gr41 indicated that part of the o-amide had been completely broken down by the strong oxidizing agent1 though the proportion of o- p-amides in the original mixtures was known only approximately4 ,the evolution of gas during the oxidation would point to the same conclusion4 ,although this effects a complete separation it is hardly economical since it will be shown later that a separation can be conveniently effected after the oxidation with ,k,mn,o#d so that the o-amide contained in the mixture need not be lost4 ,the original mass was treated with successive portions of water till nothing remained but a black tarry substance4 ,the amide which separated from these extracts was perfectly white and melted at #aec-e4 ,it was therefore regarded as practically pure o-amide4 ,the yield in amide melting above #aec was a little over one sixth the weight of toluene used4 ,the amide obtained in this way was oxidized in the manner already described4 ,it was found however that there was always some benzoic p-sulphamide in the solution of the oxidation1 due to the slight admixture of p- with the o-amide used4 ,this is thrown down with the sulphinide on acidifying the solution and may be removed by re-crystallization since it is somewhat less soluble in hot and cold water than sulphinide4 ,a better way to effect the separation1 however1 was found to be the following4 ,after having evaporated the solution containing the products of oxidation1 nearly neutralized with ,h,cl1 to about one fifth its original volume1 it is made very slightly acid and allowed to cool4 ,in this way very nearly all the benzoic p-sulphamide is separated from the solution and none of the sulphinide4 ,after filtering1 strong ,h,cl is added and the sulphinide then separates in its characteristic form4 ,this indicates that sulphinide forms an alkaline salt which is not decomposed by diluted ,h,cl while the p-sulphamide does not4 ,the mixture of amides meeting at #aje-abj was oxidized and the products separated in this way gave about equal quantities of sulphinide and benzoic p-sulphamide4 ,when toluene is treated with chlorsulphonic acid there are formed besides the ortho- and para- chlorides also ortho and para sulphonic acids4 ,these of course are in solution in the water from which the chlorides separated4 ,in order to recover the ortho-acid1 the solution was neutralized with chalk forming the calcium salt3 this converted into the potassium salt which by evaporating the solution to dryness was obtained as a white crystalline powder4 ,when treated with ,p,cl#e in the manner already described this gave a mixture of ortho and para sulphonchlorides consisting of about ortho and para4 ,formation of ,orthosulphobenzoic acid from ,sulphinide4 ,benzoic sulphinide may be converted into a sulpho-benzoic acid 7#a7 by boiling with ,ba7,,oh7#b1 7#b7 by heating in a closed tube with conc4 ,h,cl or 7#c7 by evaporating on the water bath with ,h,cl4 #a4 ,three gramms of sulphinide were boiled in a flask connected with an inverted condenser for about two days with an excess of ,ba7,,oh7#b4 ,there was formed in the flask a hard mineral-like mass which was insoluble in water and cold diluted ,h,cl but dissolved in hot ,h,cl with effervesence4 ,this was a ,barium salt1 probably basic 787 of ortho sulphobenzoic acid4 ,there was also formed an easily soluble barium salt of that acid4 ,the former was dissolved in ,h#b,,so#d and treated with ,ba,c,o#c2 the filtrate from the ,ba,s,o#d which contained a soluble barium salt was added to that above mentioned and the barium exactly precipitated with ,h#b,,so#d and the filtrate evaporated to dryness giving the free acid but not in a perfectly pure condition4 #b4 #b4ge gr4 of sulphinide was sealed up in a tube with pure conc4 ,h,cl and heated two hours to #aej4 ,on cooling nothing separated2 the liquid was evaporated to dryness giving #c4b gr of acid and ammonium chloride4 ,the reaction taking place here may be represented thus3 ,,co ,,cooh ,c#f;,h#d ,,nh #b;,h#b,o ,h,cl ,c#f;,h#d ,,nh#d;,cl4 ,,so#b ,,so#b,,oh #c4 ,a more convenient method for obtaining the acid than either of the above1 is to heat the sulphinide with conc4 ,h,cl on the water bath for two days4 ,then evaporate to dryness and dissolve the residue in a small quantity of water4 ,if the sulphinide contained any para-sulphamide1 as is usually the case1 this will be left undissolved and most of the ,,nh#d;,cl will crystallize on standing4 ,this solution by slow evaporation deposits large colorless crystals of the free acid4 ,this acid is soluble in about two parts of cold water1 very difficultly soluble in absolute alcohol and almost completely insoluble in ether4 ,it does not melt under #bej but considerably above that it melts1 at first apparently without change and then with slight sublimation of a very deliquescent substance1 probably the anhydride4 ,two determinations of the ,s4 made by ,mr4 ,a4 ,f4 ,linn1 gave the following results4 ,i #aceh gr substance gave #ahee gr ,ba,s,o#d representing #aegb ,s4 ,,ii 0 0 0 0 0 0 ,,cooh ,calculated for the formula ,c#f;,h#d #aehd ,s4 ,,so#b,,oh ,illustration ,a crystallographic examination of the acid showed it to belong to the orthorhombic system4 ,axial ratio3 a3 b3 c #hejg3 #a3 #haba4 ,planes4 and 4 ,edge ,x #aca #h' 0 ,y #hb #ah' 0 ,z #aah #dj' ,angles measured #aad #ch' ,the crystals are up to #h mm in length4 ,the pyramidal faces are generally etched so that the image is poor4 ,sulphonfluorescen4 ,several attempts had already been made to obtain from the action of o-sulphobenzoic acid and resorcin a substance analogous to the fluorescen obtained by ,baeyer#a from phthalic anhydride and resorcin but while a strongly fluorescent substance was easily obtained1 no definite compound could be separated from it4 ,thus ,palmer obtained1 by heating together the above named substances to #afj787 a solid mass1 part soluble in water and part insoluble as a dark brown amorphous powder4 ,both parts gave a strong fluorescence with alkalis4 ,he was unable however to obtain the substance itself or any derivative in a crystalline form4 #a ,annalin4 ,no4 #ahc4 ,s4 #a4 ,no4 #bjb4 ,s4 #cf ,s4 #aec4 ,berichte4 ,no4 ,,iv4 ,s4 #deg4 #eee4 #feh4 #ffb4 0 0 ,,viii4 ,s4 #ff4 #adf4 ,the first experiments in this series gave the same negative results4 ,the mixture of acid and resorcin was heated in a sulphuric acid both for several hours to #aej-agj1 and as it showed no sign of solidification the temperature was raised to #bjj and then to #bce where it was kept several hours longer4 ,the black viscous mass obtained in this way became vitreous on cooling1 and in all respects resembled that described by ,palmer4 ,this however is not the normal course of the reaction as shown later but is probably due to a decomposition of the normal product produced by too high heating4 ,an experiment was made with the acid salt of ortho-sulphobenzoic acid4 ,,cooh ,c#f;,h#d ,,so#b,,ok1 resorcin and ,h#b,,so#d heating the mixture to #aej-agj4 ,a solid black mass was obtained strongly fluorescent in alkaline solution and in all other respects like the substance obtained above4 ,preparation of ,sulphonfluorescen4 ,as the result of a number of experiments the following method of preparing and purifying the sulphonfluorescen was found to give the best results4 ,the free acid is mixed with resorcin in the proportion of #a part acid to #a4b parts resorcin1 or a slight excess over two molecules of the latter to one of the former4 ,the mixture is placed in a deep vessel1 a test tube or beaker1 which is placed in a sulphuric acid bath1 a thermometer being suspended in the mixture4 ,the bath is heated and at about #ajj the resorcin melts and the acid slowly dissolves in the liquid4 ,no action appears to take place till the temperature reaches #age where water begins to be given off and the liquid slowly assumes a darker color4 ,white crystals of resorcin collect on the sides of the vessel4 ,after the heating has been continued for about seven hours at #agh-ahe the liquid has a clear deep red color but shows no signs of becoming viscous4 ,at length lustrous yellow crystalline plates appear in the liquid and soon the whole mass becomes a thick nearly solid yellow paste4 ,continuous heating at the same temperature causes no further apparent change4 ,this mass1 which on cooling is made up of yellow crystals imbedded in a red vitreous matrix1 is then dissolved in hot water forming a clear red solution or at most one containing but a small quantity of a brown flocculent precipitate4 ,this solution is filtered if necessary and evaporated to a small volume from which the substance separates on cooling in reddish yellow radial crystals4 ,these are filtered and washed with ether till the washings are perfectly colorless4 ,the substance on repeated crystallization from water has a pale straw yellow color and when deposited slowly forms transparent crystal blocks from #bf mm long1 arranged in radial groups4 ,a considerable amount of resorcin is lost by sublimation during the reaction especially if the operation is carried on in a beaker so that some excess should be added4 ,but even when the resorcin is present in excess at the end of the reaction some free acid is always left which may be obtained from the mother liquid in the characteristic colorless orthorhombic crystals4 ,the water of crystallization and sulphur were determined in the new compound4 ,in estimating the water1 the substance was heated to #ajf-abc for about ten hours till it attained a constant weight4 ,on standing in the air it quickly regains its original weight4 ,when heated to #acj-adj for some time it turns slightly reddish and loses over #aj of its weight which is not regained by standing in the air4 ,estimation ,no4 ,i4 was made by fusion with ,,koh and ,,kno#c4 ,nos4 ,,ii and ,,iii were made by ,mr4 ,mindileff by ,morse's method1 oxidizing with ,k,mn,o#d in ,,koh solution4 #chhb gr4 heated to #ajf-abc lost #jcjb gr4 #he ,calculation for #b;,h#b,o - ,c#ai;,h#ab,o#f,s#b;,h#b,o #hi water4 ,i4 #bjjg gr sub4 gave #abhf gr ,ba,s,o#d #hgg ,s4 ,,ii4 gr 0 0 0 gr 0 #gia0 0 ,,iii4 gr 0 0 0 gr 0 #ghi0 0 ,calculation for ,c#ai;,h#ab,o#f,s#b;,h#b,o #gib ,s4 ,these analyses show with but little doubt that the substance has the composition indicated above i4e4 ,c#ai;,h#ab,o#f,s#b;,h#b,o4 ,the reaction therefore which takes place between ortho-sulpho benzoic acid and resorcin from its analogy to that taking place between phthalic anhydride and resorcin may be represented thus1 as shown by ,baeyer in his second paper 7,ann4 #bjb4 ,s4 #dc7 ,representing the formation of the anhydride as the first action4 ,,cooh ,,co ,c#f;,h#d ,c#f;,h#d ,o ,h#b,o ,,so#b,,oh7o7 ,,so#b and the action of resorcin on this anhydride thus4 ,,co ,,oh ,c#f;,h#d ,o #b;,c#f;,h#d ,,so#b ,,oh 7m7 ,o 7,,ho7,h#d;,c#f ,c#f;,h#d7,,oh7 ,c #b;,h#b,o ,c#f;,h#d ,o ,,so#b ,the substance thus formed would naturally receive the name ,sulphonfluorescen from its analogy with ,fluorescen4 ,,oh ,c#f;,h#c ,o ,c ,c#f;,h#c ,,oh ,c#f;,h#d,,so#b ,o ,sulphonfluorescen4 ,,oh ,c#f;,h#c ,o ,c ,c#f;,h#c ,,oh ,c#f;,h#d;,,co ,o ,fluorescen4 ,properties of ,s4fluorescen4 ,this compound shows a marked similarity to the fluorescen described by ,baeyer as would naturally be expected from its great similarity of composition and constitution1 but it also shows decided differences which may be attributed to the replacement of ,,co by ,,so#b4 ,dissolved in water it shows a weak green fluorescence which in alkaline solution becomes much deeper but not by any means so strong as that of fluorescen4 ,the dilute alkaline solution by transmitted light is almost perfectly colorless and by reflected light a clear green4 ,unlike fluorescen it is extremely soluble in water1 about one part in two or three of hot and five or six of cold water4 ,it is also soluble in absolute alcohol forming a yellow solution with weak fluorescence4 ,it is soluble with difficulty in ether but when in solution is deposited only on evaporating to a small volume4 ,it does not melt at #bej but if held at a lower temperature for a long time becomes red undergoing some decomposition4 ,if quickly heated somewhat above #cjj it melts to a deep red liquid and then solidifies4 ,if the mass is treated with water it partly dissolves leaving a dark brown flocculent precipitate which dissolves on the addition of an alkali1 the solution having an intense fluorescence1 nearly if not quite equaling that of fluorescen4 ,this change produced by heating was not further studied4 ,the crystals are very thin blades1 apparently monoclinic1 showing the clinopinacoid and a very narrow prism and clinodome 4 ,the angle #ge and the extinction angle against the axis #bj4 ,the axial ratio could not be accurately determined4 ,salts of sulphonfluorescen4 ,the influence of the ,,so#b group is shown by the fact that the substance acts as an acid decomposing carbonates and forming salts which is not the case with fluorescen4 ,barium salt4 ,the substance was boiled with an excess of carefully purified ,ba,c,o#c for two hours4 ,the filtrate from the ,ba,c,o#c evaporated to a small volume deposited yellow crystals resembling the original substance but in shorter and thicker prisms4 ,these were twice recrystallized and had then a light straw yellow color4 ,a determination of the ,ba gave the following results4 ,the salt was dried in the air4 ,transcriber's ,note3 ,the following table was crossed out on the original4 ,a note on the previous page beside the table was3 ,all these calculations are wrong4 ,j4,r4 ,i #ajgh gr salt gave #jcjd gr ,ba,s,o#d #aegc ,ba4 ,,ii #afda 0 0 0 #jdeg 0 0 #aeec0 0 ,,iii #bdbe 0 0 0 #jfhj 0 0 #aefe0 0 ,,iv #bhfj 0 0 0 #jgih 0 0 #aeed0 0 ,v #ahdc 0 0 0 #jdih 0 0 #aejh0 0 ,,vi #bfbj 0 0 0 #jgjh 0 0 #aejh0 0 ,,vii #cbcj 0 0 0 #jijf 0 0 #aefe0 0 ,,viii #bhge 0 0 0 #jhjg 0 0 #aeff0 0 ,calculated for ,c#ai;,h#ac,o#g,s,ba #aeaj ,ba4 ,in the above determinations the salt analysed was taken from specimens made at three different times and purified in slightly different ways1 ,nos #a1 #b1 #c being washed with absolute alcohol4 ,nos ,v and ,v were made by precipitating the ,ba with ,h#b,,so#d from a solution of the salt4 ,the water was determined by heating at #aaj till constant weight was reached4 ,part only of the weight lost was regained on standing in the air4 #cidc gr salt lost at #aaj #jbhf gr #g4be ,water calculated for ,c#ai;,h#ac,o#g,s,ba#b;,h#b,o #g4ce ,although these analyses show a per cent4 of ,ba somewhat above that required by a compound having the formula ,c#ai;,h#ac,o#g,s,ba still this appears to be the most probable formula which can be assigned to the substance4 ,if this is the true composition of the salt1 then in sulphonfluorescen the anhydride condition must be broken up by boiling with ,ba,c,o#c forming the salt thus4 ,,oh ,,oh _/ _/ ,c#f;,h#c ,c#f;,h#c ,o ,o _/ _/ ,c ,c#f;,h#c ,c#f;,h#c ,h#b,o ,c ,,oh ,,oh ,c#f;,h#d,,so#b ,c#f;,h#d,,so#b,,oh _/ ,o ,,oh ,,oh ,,oh _/ _/ ,c#f;,h#c ,c#f;,h#c ,o ,o _/ _/ ,c#f;,h#c ,c#f;,h#c #b ,c ,ba,c,o#c ,c ,ba4 ,,oh ,,oh ,c#f;,h#d,,so#b,,oh ,c#f;,h#d,,so#b,o ,,oh ,,oh #b ,by treating the salt with ,h#b,,so#d the original substance is reformed4 ,calcium ,salt4 ,attempts were made to prepare the calcium salt but without success4 ,the ,s-fluorescen was boiled several hours with very finely powdered calcite1 and some salt was formed as shown by the ,,co#b evolved but on evaporating the solution and recrystallizing the substance deposited it was found to be the unchanged ,s-fluorescen4 ,some ,ca4 salt was in the mother liquors but its extreme solubility prevented a separation being made4 ,acetyl derivative of ,s4fluorescen4 ,s4fluorescen was boiled with an excess of acetic anhydride for about three hours4 ,the solution became quite dark and when evaporated on the water bath left a black tarry residue4 ,this was treated with water which dissolved a part leaving a dark flocculent precipitate4 ,the solution was boiled with animal charcoal and evaporated nearly to dryness4 ,on cooling there separated a light yellow flocculent precipitate very soluble in hot water and but slightly less so in cold4 ,this was dissolved in a small quantity of alcohol from which it separated on evaporation in small radial crystals having a light lavender color satiny luster4 ,they also have a peculiar odor resembling slippery elm which is not removed by recrystallization4 ,they show a tendency to decompose1 becoming yellow on exposure to the air4 ,the substance does not melt or change in appearance under #bde4 ,with alkalis it gives a slight greenish fluorescence4 ,from the method of its formation this was taken to be an acetyl derivative of ,s4fluorescen but whether the mono-or di-acetyl could not be determined without analysis for which the substance did not suffice4 ,bromine substitution products of ,s-fluorescen4 ,it was especially interesting to see what influence the ,,so#b group would exert upon the introduction of ,bromine into the compound4 ,in the case of fluorescen four ,bromine atoms enter easily and special precautions are necessary to obtain a product containing a smaller number4 ,the case however is different with ,s4fluorescen4 ,the latter was dissolved in glacial acetic acid in which it is soluble with some difficulty and to the solution was added a #bj solution of bromine in acetic acid1 in sufficient quantity to make eight atoms of bromine to one molecule of ,s4fluorescen4 ,this solution was evaporated on the water bath and while still having a considerable volume1 small1 red1 sharply defined crystals began to separate4 ,the solution was evaporated to a small volume and allowed to cool but nothing further separated4 ,these crystals are difficultly soluble in water1 alcohol and ether4 ,the alkaline solution shows a green fluorescence and slight red color by transmitted light4 ,these crystals were dissolved in a large quantity of alcohol which on evaporation gradually deposited very small yellow crystals1 which were dried in the air and taken for analysis4 ,the ,br4 was determined by ,carius method4 ,i4 #bcde gr sub4 gave #agah gr ,ag,br #caag ,br4 ,,ii4 #bghf gr 0 0 #ahae gr 0 #bggb ,br4 ,calculated for ,c#ai;,h#aj;,br#b,o#f,s #cjdb ,br4 ,these results1 though not conclusive1 indicate that under the given conditions it is the di-bromsulphonfluorescen which is formed4 ,whether this is due to the presence in the compound of the ,,so#b group or simply to the greater insolubility of the di-than of the tetra-brom product cannot be definitely stated4 ,when the original acetic acid mother liquor was evaporated to dryness1 a red non-crystalline substance remained which more closely resembled rosin than the crystals4 ,the concentrated alkaline solution had a deep red color without fluorescence and acted as a red dye stuff4 ,the dilute alkaline solution showed the characteristic delicate pink of rosin4 ,action of ,h#b,,so#d on ,s4fluorescen4 ,a test tube in which ,s4fluorescen was being made just at the end of the reaction broke and allowed the contents to run out into the sulphuric acid bath1 which had a temperature of #age4 ,on standing several days the solution deposited a heavy precipitate which was separated by filtering through glass wool4 ,when dry it formed a light yellow powder extremely soluble in water1 alcohol and ether4 ,the alkaline solution had an intense green fluorescence with delicate shades of pink by transmitted light4 ,on account of its great solubility it was impossible to purify it by crystallization1 hence the ,ba salt was made4 ,the substance decomposed ,ba,c,o#c with great ease forming an easily soluble salt4 ,when it was attempted to evaporate the solution of this salt to crystallization the latter came out in a hard insoluble granular form and on continuous boiling of the solution turned brown4 ,to avoid this undesirable form it was converted into the ,ca4 salt by treatment with ,h#b,,so#d and then ,ca,c,o#c4 ,this also formed a hard granular insoluble mass on boiling but did not change in color4 ,as there was no guarantee as to its purity and only a small quantity was obtained it was not analyzed4 ,action of ,h,cl on ,s4fluorescen4 ,hydrochloric acid does not dissolve ,s4fluorescen but converts it into a light yellow granular powder4 ,when recrystallized from water in which it is quite easily soluble it melts partially at #acj apparently with some decomposition4 ,this compound was not further studied4 ,reduction of ,s4fluorescen4 ,when treated with zinc dust in a strong alkaline solution sulphonfluorescen is reduced to a colorless substance probably analogous to fluorescen which is formed in the same manner4 ,on account of its great solubility it could not be obtained in the free state4 ,it is quickly oxidized to s4fluorescen by oxidizing agents as ,k,mn,o#d and ,,hno#c and passes back spontaneously on standing in the air4 ,the latter action is however much slower than in case of fluorescen4 ,conclusion4 ,the principal results relating to s4fluorescen which have been reached in this work may be briefly summarized as follows4 ,orthosulphobenzoic acid acts on resorcin at a temperature of about #ahj giving off water and forming a substance analogous to fluorescen but having the ,,co group replaced by ,,so#b4 ,this substance sulphonfluorescen crystallizes from water in light yellow monoclinic crystals having the composition ,c#ai;,h#ab,o#f,s#b;,h#b,o4 ,it is very soluble in alcohol and water and with difficulty in ether4 ,it does not melt under #bej but above #cjj melts with decomposition4 ,it shows in alkaline solution a clear green fluorescence4 ,it acts as an acid1 decomposing carbonates and forming salts1 the ,ba salt having the composition ,c#ai;,h#ac,o#g,s,ba4 ,it forms an acetyl compound when boiled with acetic anhydride4 ,it forms substitution products with ,br1 probably the dibrom-product most easily4 ,it forms a compound with ,h#b,,so#d1 probably a substitution product1 whose composition was not determined4 ,it is reduced by zinc dust and ,,koh to a colorless substance analogous to fluorescen4 ,finally in terms of the prevalent theory the substance itself may be represented thus-- ,h ,h ,c ,o ,c ,,oh 7,,ho7,c ,c ,c ,c7,,ho7 ,c#f;,h#c ,,hc ,c ,c ,,ch ,o ,c ,c ,c ,c ,h ,h ,c#f;,h#c ,,hc ,,oh ,,hc ,c ,o ,c#f;,h#d,,so#b ,,hc ,c ,o ,c ,,so#b ,h