51 VII1.-Miscellaneous Obseruatjons. BY A. W HOFMANN. 11. (Continued from Vol. X ,p. 211.) 4. Action of Nitrous Acid upon Nitrophenylene-c~~~~e. THE experiments of Gottlieb have shown that dinitrophenyl- arnine when boiled with sulphide of ammonium is converted into a remarkable base crystallising in crimson needles generally known as Nitraxophenylamine and for which in accordance with the views I entertain regarding its constitution I now propose the name iVitro~henyZene-diamine. I owe to the kindness of Dr. Vincent Hall a considerable quantity of this substance which is not quite easily procured. In preparing it DP. Hall has in the first place followed the succession of processes recommended by Got tlie b viz. treatment of phenyl-citraconimide (citraconanile) with nitro-sulphuric acid transformation of the nitro-substitute into dinitrophenylamine and the reduction of the latter by sulphide of ammonium.In other experiments Dr. Hall has availed himself with the same advantage of phenyl-succinimide (succinanile) which under the influence of a mixture of nitric and sulphuric acid exhibits a deportment similar to that of the citraconyl-body. Dinitrophenyl-succinimide is readily transformed into dinitro-phenylamine which ultimately yields the crimson-coloured com- pound. To the accurate description which Gottlieb has given of the preparation and the properties of this substance I have scarcely to add a single word. The following remarks refer to an experi-ment made with the view of obtaining some insight into the molecular construction of the body.If bearing in mind the hUIzlerOUs analogies of the radicals ethyl and phenyl we assume that the latter by the loss of hydrogen may be converted into a diatomic molecule pheuylene C6H4,* comespondkg to ethgldne the existence of a group of phenylene-bases corresponding to the ethylene-bases camot be doubted. * H=I C=12,O=lG 8=32,etc. E2 HOFMANN ON ACTfON OF NITROUS ACID (C2H,)”] Ethylamine c2:5] N Ethylene-diamine €1 N H H2 Phenylamine ‘f?)N Phenylene-diarnine(C6g’’1N2. H H2 The compound known as semibenzidam or azophenylamine which Zinin obtained by exhausting the action of sdphide of ammonium on dinitrobenzol agrees with the last-named body in composition.Tliose chemists however who have had an opportunity of becoming acquainted with the well-defined properties of ethylene-diamine will not easily be persuaded to consider the uncouth dinitrobenzol -product sometimes appearing in brown flakes sometimes as a yellow resin rapidly turning green in contact with the air as standing to phenylamine in a relation similar to that which obtains between ethylene-diamine and ethylamine. We much more readily admit a connection of this description between phenylamine and Got tlieb’s crimson-coioured base in which the clearly pronounced character of the former is still distinctly visible although of necessity modified by the further substitution which has taken place within the radical. ‘6H51 Phen ylamine H N [“3 ” > ] *,* Nitrophenylen e- di amine H2 H2 Does the latter formula really represent the molecular constitu- tion of the crimson needles? The degree of substitution of this body might have been determined by the frequently adopted pro-cess of ethylation.But even a simpler and shorter method appeared to present itself in the beautiful mode of substituting nitrogen into the place of bydrogen lately discovered by P. Griess. The red crystals undergo indeed with the greatest facility the transformation which he has proved already for a great many derivI?tives of ammonia. (‘6 UPON NITROPHENY LENE-DIAMINE. On passing a current of nitrous acid into a moderately con-centrated solution of the nitrate of the base the liquid becomes gently heated and deposits on cooling a considerable quantity of brilliant white needles the purification of which presents no difficulty; being sparingly soluble in cold readily soluble in boiling water the new compound requires only to be once or twice re-crystallised.Thus purified the new substance forms long prismatic crystals frequently interlaced white as long as they are in the solution but assuming a slightly yellowish tint when dried and especially when exposed to looo; they are readily soluble both in alcohol and in ether. The new body exhibits a distinctly acid reaction; it dissolves on application of a gentle heat in potassa and ammonia without however neutralizing the alkaline character of these bases; it also dissolves in the alkaline carbonates but without expelling their carbonic acid.The new acid fuses at 211O C. and sublimes at a somewhat higher temperature with partial decomposition. The sublimate consists of small prismatic crystals. Analysis gave the following results :-I. 0.3290 grm. acid dried at loo" gave 0*5298 , carbonic acid and 00777 , water. 11. 0-2868grm. acid gave 84 cc. moist nitrogen at 15O and 0.7583Bar. (corr.) These numbers lead to the ratio:- and the origin of the substance being taken into coasiderakkm fA the formula :-CG~4~*02* Theory. Experiment. I. 11. C 72 43.90 43-92 -fi* 4 2.44 2.62 -N 56 34.15 -34.32 LI .-. 0 32 1951 -1_1-1641 100*00 This fornd is confirmed by the analysis of the silver- and of the potassium-compound.HOPlrZAIW ON ACTION OF NITROUS ACID SiZ~er~saZt.This salt is obtained in the form of a white amorphous precipitate on mixing the saturated ammonia-solution of the acid with nitrate of silver. 1%wucuo this salt may be dried without decomposition; at 100' it becomes slightly coloured ; when gently heated on platinum foil it detonates. The silver therefore had to be estimated as chloride. 1 0.4215 grm. silver-salt gave 0*4068 , carbonic acid and 0.0487 , water. 11. cI.2984 , silver-salt gave 0.1574 , chloride of silver. The formula C,fH,Agf N402involves the following values :-Theory. Experiment. C 72 26-57 I. 26.32 11. - H3 3 1.11 1.28 - N4Ag 56 108 20.66 39.85 - L 3967 0 32 ll*81 - I_ I__ 271 100*00 Patssizcm-salt.Obtained in pretty well -formed flattened prisms by saturating a moderately concentrated boiling solution of potassa with the acid; the crystals are difficultly soluble in potassa but exceedingly soluble in pure water and in alcohol ; the recrystdization is therefore attended with very considerable loss. The aqueous solution of the salt yields a crystalline precipitate on addition of potassa. The salt even after four or five recrystal- lizations from alcohol retairis a distinctly alkaline reaction. Its composition was fixed by a potassium determination. 0.2012grm. salt dried at 100° gave 0.0857 , sulphate of potassium. UPON NITBOPEENPLENE-DIAMINE. 55 The formula C CH3K] N,O requires the following values :-Theory Experiment.C 72 35.64 -I J33 3 1*48 K 39 19.31 19.10 N 56 27.72 -0 32 15.85 -___. -202 100.00 With regard to the other salts I have made but fmv observa-tions. The ammonium-salt crystallizes in needles. It has however but little stability losing the whole of the ammonia when re-peatedly recrystallized. The solution of this salt exhibits with metallic oxides the following deportment. Barium and calcium-salts are not precipitated. Salts of copper give a light blue salts of nickel a light green precipitatc. The solution of a ferrous salt produces a deep brown-red precipitate probably with simultaneous decomposition of the acid; the solution of a ferric salt a light fawn-coloured precipitate. The salts of ~~o~ lead zinc manganese and mercury (~e~ and mercuricum) u~ furnish white flaky precipitates.The analysis of the new compound shows that under the influence of nitrous acid on nitrophenylene-diamine one molecule of nitrogen is substituted into the place of three molecules of hydrogen which are eliminated in the form of water C,H,N,O + X-INO = 2 N,O -I-C6[H4N]N,0 Nitrophenylene-New acid. diamine. I do not propose a name for the new compound which can claim but a passing interest as throwing by its formation some light on the constitution of nitrophenylene-diamine. The composition of the new acid and of its salts shows that in the crimson base four hydrogen molecules are still capable of' replacement; in other words that this body still contains four extra-radical molecules of hydrogen.These experiments appear to confirm the view which in the commencement of this note I have taken of the constitution of the body; at all events the mutual relation of the several compounds is satisfactorily illus- trated by the fol.nnulze- New acid If the admissibility of this interpretation be confirmed by further experiments the reaction discovered by Gri e ss furnishes a new and valuable method of recognising the degree of substitu-tion in the derivatives of ammonia. The new acid differs in many respects from the substances similarly produced from other nitrogenous compounds. As c2 class these substances are remarkable for the facility with which they are changed under the influence of acids and more especially of bases.The new acid exhibits remarkable stability ; it may be boiled either with potassa or with hydrochloric acid without undergoing the slightest change. Even a current of nitrous acid passed into either the aqueous or alcoholic solu- tion is without the slightest effect. The latter experiment was repeatedly performed; for if the action of nitrous acid in a second phase of the process had assumed the forin so frequently observed by Piria and others it might have led to the formation of the diatomic nitroph~nylene-alcohol according to the equation It deserves to be noticed tliat nitrophenylene-diamine although derived from two molecules of ammonia is nevertheless a decidedly mono-acid base. pot tlieb’s analyses of the chloride nitrate and sulphatc left scarcely a doubt on this point.How-ever as some of the natural bases quinine for instance are UPON NITliOl’HEEX’Y LICK E-1,I A 311h’li capable of combining either with one or with .two molecules of acid I thought it of sufficient interest to confirm Gottlieb’s observations by some additional experiments. The crystals depo- sited on cooling from a solution of nitrophenylene-diamine in concentrated hydrochloric acid werc washed with the same liquid and dried in vacuo over lime. 0.3975 grm. substaiice gave 0.3005 , chloride of silver = 18.70 p. c. of chlorine. The formula requires 18.73 p. c. of chtorinc. The dilute solution of the previous salt is not precipitated by dichloride of platinum; nor could the double salt of the two chlorides be obtained by evaporating thc mixture of the two solutions which just as Got t 1ie b observed was readily decom- posed with separation of inetallic platinum.I had hornever no difficulty in preparing a platinum-salt crystallizing in splendid long brown-red prisms by adding the platinum solution to the concentrated solution of the hydrochlorat e. Q*4225grm. of the platinum-salt dried in uucuo left on ignition 0.115 grni. = 27.22 p. c. of platinum. The theoretical percentage of the formula is 27.48 p. c. of platinum. These experiments prove that even uiider thc most favourable circumstances nitrophenylene-diamine combines with only 1eq. of acid while the ethylene-deriyatives are decidedly diacid. The diminution of saturating power in uiti~~vhenglene-diamin~ at the first glance seems somewhat anomalous ; but the anomaly disap- pears if the coustitution of the body be more accuratcly examined.It cannot be doubted that the diminutioii of the saturating power is clue to the substitution which has talten place within the radical HOP1MAXN ON ACTIOX OF NITROUB ACID of the diamine. J pointed out some time ago,* that the basic character of phenylamine itseif is considerably modified by suc- cessive changes induced in the pheny l-radical by substitution Chlorphenylamine though less basic than the normal compound still forms well-defined salts with the acids; the salts of dichlor-phenylamine on the other hand are so feeble that under the influence of boiling water they are split into their constituents; and in trichlorphenylamine the basic character has entirely dis- appeared.Again on examining the nitro-substitutes of pheny-lamine we find that even nitrophcnylamine is an exceedingly weak base whilst dinitrophenylamine is perfectly indifferent. What wonder then that a molecular system to which in the normal condition we attribute a diacid character should by the insertion of special radicals be reduced to monoacidity? The normal phenylene-diamine which remains to be discovered will doubt- less be found to be diacid like the diamines derived from ethylene. Even now the group of diacid diamines is represented in the naphtyl-series. Napht ylamine "''g7] N monoacid. H 10 6 Naphtylene-diamine N, diacid.'' &)] 1% The body which I designate by the term naphtylene-diamine is the base which Zinin obtained by the final action of sulphide of ammonium upon dinitronaphtalin This substance originally designated as seminaphtalidam and subsequently described as naphtalidine corn bines according to Zinin's experiments with two equivalents of hydrochloric acid.? I must add a remark suggested by the perusal of ail interest- ing paper lately published by Kolbe.1 In this paper Kolbe refers to an outline of the history of ammonia and its derivatives which in the form of an evening lecture I gave to the members of this Society and which was subsequently printed in this journal.$ Kolbe regards many of the ammonia-cornpounds from a different point of view and expresses them by molecular * Mem.of Chem. SOC.,ii 298. C Ann. Ch. Pharm. lxxxv 328. $ Ueber den naturlichen Zusammenhang der organischen rnit den unorgwniscben Verbindungen.-Ann. Ch. Pharm. cxiii 293, $ Cbem. SOC.Qu J. xi 65% UPON NITROPHENYLENE-D;iAMIME. 50 formulae different from those which I have adopted. It is not my intention to refer in detail to the several qnestions which he discusses mQre cspecially since many of the theoretical views in which we differ were brought forward by others and mere simply introduced into the sketch with the view of rendering it as complete as possible; yet I must riot allow this opportunity to pass without a word or two in elucidation of a question on which we differ more in appearance than in reality.In classifying the basic ammonia-derivatives I proposed to designate the substances formed by the coalescence of more than one molecule of ammonia in accordance with the nomenclature adopted for the neutral derivatives and to distinguish as mona- mines diarnines and triamines the bases derived from one two or three molecules of ammonia. In a classification of this kind the circumstance could not be left unnoticed that inany of the diamines and triamines combine with one equivalent of acid only instead of saturating as might have been expected from their construction two or three equivalents. I was thus natu- rally led to subdivide again and to distinguish for instance monoacid and diacid diamines and I added It is obvious that the question whether a diamine is capable of uniting with one or two equivalents of acid must be intimately connected with the molecular construction of the basic system As yet the nature of this connection remains unknown.” In the paper quoted Kolbe remarks lCThere appears no reason why among the bodies derived from two molecules of ammonia there should be side by side with the diatomic sub- stances others yielding monoatomic ammonium-compounds.I cannot therefore consent to regard the ureas melaniline and other bases containing two atoms of nitrogen as true diamines.” It is scarcely neceswp to state that I entirely agree with my friend if he views as true diamines those bases which unite with two equivalents of acid; for it is proved experimentally that the ureas and melaniline combine with oiie equivalent of acid only All depends upon the definition of the word diamine.X had de- signated by this name basic compounds dmived from two molecules of ammonia without reference to the degree of saturating power ; and even now it appears to me somemhltt arbitrary to limit this term to those substances which unite with two equivalents of acid especially since there are diatomic bases which are capable ctf combining either with one or with two equivalents of acid. NOFXA" ON T11X ACTION OF BISULPEIIDE OF 5 Action of Bisulphide of Carbon upon Amylamine. In a note on the alleged transformation of thialdine into leucinc communicated some time ago* to the Chemical Society I alluded to a crystalline substance observed by "Vagner when he sub- mitted amylamine to the action of bisulphide of carbon.Wagner had not analysed this substance but considering its mode of formation he had suggested that it might posaibly be thialdine A simple comparison of the properties of thialdine with those of the substancc produced by the action of bisulphide of carbon upon amylamine had enabled me at once to recognise the differ- ence between the two bodies; and satisfied with the result I had not at the time examined more minutely iuto the nature of the latter substance. The new interest conferred by recent researches upon leuciiie and its homologues has recalled my attention to the sulphuretted derivative of amylamine. This body may be readily procured by mixing anhydrous amyl- amine with a solution of dry bisulphide of carbon in anhydrous ether.The inixture becomes warm and deposits on cooling white shining scales which are insoluble in ether and may there-fore be purified by washing them with this liquid. The new body is likewise insoluble in water but readily dissolves in alcohol; when dry it may be exposed for a while to a temperature of 100"C. without fusing; after some time however the substance begins to be liquefied and to undergo complete decomposition sulphuretted hydrogen being evolved. The same change occurs although more slowly at the common temperature; a mixture of free sulphur with a new crystalline body extremely fusible inso- luble in water but soluble both in alcohol and ether remaining behind.I. 0.274grm. of the amylsmine-body burnt with a mixture of oxide of copper and chromate of lead gave 0.535 grm. of carbonic acid and 0.2535 grm. of water. * d'hem. Soc. Qu. J. H 103. H-1 C=l% O=16 8=32. CARBON UPOX AMPLAMIPI’E. GI 11. 0.429 grm. of substance dissolved in alcohol and boiled for some time with nitrate of silver gave 0.837 grm. of sulphide of silver. These numbcrs lead to the formula Theory. Experiment. I. 11. C, 132 5.2.8 53.25 -10.28 -I-I!26 26 10.4 I N2 28 11.2 -s!2 -64 25.6 -25.17 -250 100.0 The new substance then is formed simply by the union of two mole- cules of amylamine with one molecule of bisulphide of carbon. 2C,H13Ni-CS = C11H26N2S2 Amylamine. New cornpound.A glance at this formula suffices to characterize this substance as amyl-sulphocarbamate of amylammonium This view is readily confirmed by experiment. Addition of hydrochloric acid to the crystalline compound immediately sepa- rates an oily liquid which gradually solidifies and the acid soln- tion then contains amylamine which may be liberated by potassa. The oily substance is obviously amyl-sulphocarbamic acid. This body is readily soluble in ether by which it may be separated from the chloride of amylammonium; it dissolves in ammonia and in potassa ; mixed with amylaiaine it reproduces the origind crystal- line compound. Experiments with ethylamine have furnished perfectly analogous results. I have been satisfied to establish qualitatively the analogy of the reactions.It is of some interest to compare the deportment of amylamine under the influence of bisulphide of carbon with that of phenyl-arnine in the same conditions If them two bodies gave rise to HOFXANN ON similar changes we should expect in the case of phenylamine the formation of phenyl-sulphocarbarnate of phenylammonium. But experiment proves that phenylamine produces diphenyl- sulpliocar- honyl-diamide (sulphocarbanilide) sulphuretted hydrogen being evolved :-2C,H,N + CS = C,,H,,N,S + H,S. Phenylamine Diphenyl-sulpho-cahon9-diamide Nevertheless it is extremely probable that further experiments will establish the perfect analogy in the deportment of amylamine and phenylamine with bisulphide of carbon.Diphenyl-sulpho-carbonyl-diamide is probably the product of decomposition of a very unstable phenyl-sulpliocarbamate of phenylammonium-C,,H,,N2S = H,S + C1333,2NgS Phenyl sulphoearba- mate of phenylam-monium. Diphengl-sulpho-carbon yl-diamide. while a more minute examination of the crystalline substance obtained by the action of heat upon amyl-sulphocarbamate of amylammonium cannot fail to characterize it as diamyl-sulphocar-bonyl-diamide. C,lH,fP,S2 = H2f3 4-________ C,lH24N,S Amyl-aulphocarba-Dismyl-sulphocar-mate of amylani-bonyl-diamide, monium. The apparent dissimilarity of tlie two reactions would thus be reduced to the unequal stability of the sulphocarbamic acids of the amyl-and phenyl-series. 6. On the use of Pentachloride of Alztimo~yin the Preparation of Chla.l.ine-coi~~o~~~s Under a cloudless sky nobody wsuld think of preparing the tetrachloride of carbon by any other process than by acting with chlorine upon chloroform.Exposed to direct sunlight chlom- form when [distilled in an atmosphere of chlorine is rapidly csuverted into htmhloride of carbon. A London November sky iS however rather unfavourable to this process anif ps’ihert.requip- PENTACHLORIDE OF ANTIMONY. ing lately for some experiments a small quantity of the tetra- chloride I was compelled to have recourse to another method. A well-known process for which we are indebted to Prof. Kolbe consists in submitting the bisulphide of carbon to the action of chlorine at a red heat when chloride of sulphur and chloride of carbon are formed.I have repeatedly availed myself of this procem which when a large quantity of chloride of carbon is to be prepared leaves nothing to be desired. When however a small amount is rapidly required the apparatus involved in this process becomes rather inconveniently troublesome. I have therefore endeavoured to substitute chlorine in a state of combination for the free chlorine. Pentachloride of phos-phorus as is well known exerts so little action upon bisulphide of carbon that it has been found convenient to prepare the penta- chloride of phosphorus by saturating a solution of phosphorus in bigdphide of carbon with chlorine gas. There is likewise no reactiun between pentachloride of phosphorus and bisulphide of carbon at 100"under pressure ;it is only at a higher temperature that an action takes place.A. very different result is obtained when the latter compound is submitted to the action of penta-ehloride of antimony the chlorinating properties of which wewe first noticed by Wijhler. On adding pentachloride of antimony to bisulphide of carbon a tmnsparent mixture is obtained which exhibits after a few minutes a powerful reaction becoming very hot and assumiug pd dark reddish-brown colour ; the mixture deposits on cooling a oopious crystallization of terchloride of antimony interspersed with well-kmed sulphur-crystals. The liquid poured off from the crystals consists chiefly of tetrachloride of carbon retaining some bisulphide of carbon chloride of sulphur and terchtoride of antilposy 3-CS + 2SbC1 = CC1 + RSbCl + S, I had expected that the reaction mould give rise to the forma- tion of a compound SbC1,S; but I have always found that the terchloride of antimony and the sulphur are separately deposited ; and the same observation was made by Mr.H. McLeod who has frequently carried out this reaction in my laboratory modifying the proportiours and the carditions of the experiment to a consi-derable extent. The small quantity of chloride of sulphur .d.Erich is ahultaneously formed appears to be the prodnet of a secondary reaction a portion of the pentachloride not yet acted upon being reduced by the separated sulphur If the experiment be made with a couple of ounces the two liquids must be mixed in a flask provided with a vertical cooling apparatus ; the reaction is so powerful that a considerable quantity of the material would be lost without this precaution.Whilst studying this process I have allowed the two liquids to act upon each other in various proportions on employing 1 eq of bisulphide of carbon (1 part by weight) and 2 eq. of penta- chloride of antiniony (8 parts by weight) the decomposition is pretty complete; on account of the foriiiation of chloride of sulphur however thc theoretical quantity of chloride of carbon is never reached. The process yields a much more copious result when the pentachloride of antimony is mixed with a considerable excess of bisulphide of carbon and the mixture whilst boiling irm a retort is submitted to the action of a current of chlorine gas In this manner large quantities of bisulphide of carbon may be transformed into the tetrachloride by the intervention of a com-paratively small quantity of pentachloride of antimony.In order to purify the tetrachloride of carbon the product of the reaction is submitted to distillation; the liquid passing over below 1C3O is boiled for some time with a solution of potassap which removes terchloride of antimony and chloiide of sdphm together vith any undecomposed bisulphide of carbon. From the product boiling at a higher temperature a considerable quantity of pure terchloride of antimony may be recovered. The tetrachloride obtained by this process exhibits all the properties of the product obtained by other modes of preparation It boils at 77".The determination of the chlorine gave the following results :-0.195 grm. of substance ignited with lime furnished 0*7W chloride of silver. c-Theory. Experiment. -c 12 7.79 c1* 142 92.21 9256. 154 100*00 Pentachloride of antimony may be used with &antage in many-cases as a carrier of free chlorine. On heatmg a veqr moderate quantity of pentachloride of antimony in a retort cmnected with an inverted cooling apparatus and passing simultsneously currents of dry olefiant gas and chlorine through the boiling liquid a very large amount of Dutch liquid may be obtained in an exceedingly short time. In an atmosphere of pentachloricle of antimony tlie combination of the ethylene and the chlorine goes on with the greatest facility.As soon as the retort is filled with the Dutch liquid the access of the two gases is interrupted and the liquid distilled. The portion boiling below 100' requires only to be once more rectified in order to farnisli perfectly pure bichloridc of ethylene. The reaidaxe in the retort consists of a mixture of terchloride and pentacliloride of a?ztimony which may serve for a new experiment. The preparation of large quantities of pentachtoride of antimony presents no difficulty whaterer since aiitiniony combines readily with chlorine at the common temperature. &4 simple mode of proceeding consists in introducing the antimony coarsely pox- dered into a combustion-tube from 5 to 6 feet long rising at ail angle of 10" or 15' one end of which is fitted into one tubu-lature of a two-iiecked glass globe the othcr neck of the globe communicating with a tube supplying dry chlorine gas.The combination taking place in the tube the product flows baclrn ards into the globe whilst the long layer of itntimony preFents tlic escape of any chlorine. Being engaged in some experiments on the action of chloride of' carbon CC1 on the phosphorus-bases I thought it desirable to study likewise the deportment of these substances under the influence of the corresponding iodide. Bearing in mind tlic facility with which chloroform is conmrted into chloride of carbon I had some hope of procuring the iodide by thc action of dry iodine upon iodoform :-CHI3 + I = HI 3.CI (2) When a mixture of iocloform and iodine in thc equivalent pro-portions of the above equation was exposed in scaled tubes to n temperature of from 140" to 15QQC.,the iodoform was fwimd to bc changed after the lapse of some hoirrs. On opening the tubes ail acid gas was erolrccl; and on distilling the (lark solid rcsidiir with \oi. xIrr. 1' HOFMASN ON water an aromatic body passed over whicIi collected in the receiver in the form of heavy oily drops. Decolorized by potasstl and freed from water by chloride of calcium the oily body boiled at about 18Qc,a considerable portion being decomposed with evolution of liydriodic acid and the distillnte reassuming the red coloration. The liquid was therefore distilled in uacuo; it then passed over colourless and vithout decomposition at a tempera-ture scarcely higher than the hiling point of water.I. 1.222 grm. of substame burnt with chromate of lead gave 0°2077 grm. of carbonic acid and 0.0800 grm of water. 11. 0.705 grm. of substance burnt with lime furnished 1.243 grm. of iodide of silver. These numbers represent the composition of di-iodide of metlip-lene-CH,I only recently discovered by Routlerom,* Theory. Experiment. 1. IT. c 12 4.418 4.63 -%? 2 0.74 0.73 -I 254 94.78 __. 95.27 268 1oo.oc) The compourid analysed mas indeed pure di-iodide of methylenc. At a temperature near the freezing point of water it solidified in large crystalline plates and exhibited in every respect the pro- perties described by Boutlerow.The analysis of the substance received moreover additional confirmation in a variety of substi-tutions in which it was subsequently employecl. The idea naturally suggested itself that the free iodine had i10 share in the formation of the di-iodide of methylene in the process described but that the transformation of the iodoforrn was ex-clusively due to the action of heat. Experiment has verified this anticipation. Iodoforxn when heated by itself in sealed tubes at a temperature of 150OC. for several hours furnished on subsequent distillation with water a very appreciable quantity of di-iodide of methylene. A comparative experiment in which I followed the plan recommended by Boutlerow (1 eq. of iodoform and 3 eqs. of ethylatc of sodium) leads me to think that the action of heat * Cotnpt.rend. xlvi 595. yields a larger product and involves on the whole a far less troublesome operation. The inequality of the amount of pro-duct in my experiments however may possibly be ascribed to the circumstance that I have repeatedly prepared the methylene- compound by exposing iodoform to the action of heat alone while Boutlerow's process mas only once or twice adopted. The transformation of iodoform into di-iodide of methlene by one or other of these processes is strange enough and as yet remains entirely uiiexplained ;there is formed together with the methylene-compound a quantity of a brown substance the nature of which appears anything but attractive. 8. Dibrowide of Ethylene.The usual mode of preparing this compound which of late has acquired considerable interest consists in pstssing ethylene into bromine covered with a layer of water. This method is extremely tedious since in order to avoid the loss of both bro-mine and of ethylene the gas can be but slowly transmitted through the liquid. The compound may however be rapidly obtained without the slightest loss by an exceedingly simple modification of the process. A strong glass bottle of 2 or 3 litres capacity is provided with a perforated cork through which is fitted a glass tube open at both ends one of mhich reaches nearly to the bottom of the bottle whilst the other slightly projecting over the cork communicates by means of a flexible ilridia rubber tnbe with the gasholder con- taining the ethylenc.To start the operation the bottle is cletached and filled over water with ctliyleiie gast into which are then poured from 100 to 130 grm. of commercial bromine and about half that quantity of water the cork with the glass tube being immediately replaced. On gently agitating the bottle the ethylene is rapidly absorbed and on turning the stopcock of the gasholder the gas rushes into the bottle exactly as into a vacuum. If the agitation be continued a very large volume of ethylene may be thus united with bromine in an cxceedingly short space of time without the loss of a particle of the constituents or of the com- pound. As soon as the absorption becomes languid the bromine is renewed and the process continued in this manner until the accumulatioiz of the dibromide renders it desirable to interrupt 1' 2 the operation.When working upon a very large scale it is con.. venierit to insert between the absorption-bottle and the gasholder a wash-bottle filled with water or dilute potassa which serves as a gauge for the rapidity of the gas-current purifying the gas at the same time if necessary and intercepting moreover any bro-mine-vapour that may har-e risen into the iiidia rubber tube if the mixture should linve become hot in consequence of too rapid absorption. Rquantity of t-nonobrominated ethylene (bromide of yinyl) was sealed up in a glass tube with the view of preserving it. After the lapse of n night the colonrless extremely mobile liquid w8s found to have become a white porcelain-'ii!ic mass aid on opening thc tube all pressure liad disappeared.'I'he white substance was perfectly amorphous arid inodorous mid proved insoluble in water in alcohol mid in ether. When heated it was chairrecl with abundant evolution of hydrobromic acid. Analysis showed as might have been expcetec-l that the altern- tion of the monobroniinatecl ethylene had been simyly molecular. 0.2954 grm. substance burnt with chromate of lead gw'e 0*2178$ grm. of carbonic acid aid 0.0'780 grm. of water. The values corresponding to the formula C,I-f,Br are :-Theory. Experhelit. c 24 22.43 32-87 €1 3 2.80 2.93 I_ lifr 80 74-77 107 100.00 The chemical relations of broiiiide of vinyl are as yet but slightly examiiied.From its formula the body might be consi-dered as the hydrobromic ether of an alcohol homologous to allylic alcohol; this mode of viewing it however is not supported by thc general deportment of the cornixxiiiil The peculiar molr-cular transformation which it undergoes points ratIier to aldehydic relatiom aldehyde being isomeric with the alcohol in question. As in the case of aldehyde the coiiditions involving these trans- formations are utterly unknown; I have minlg tried to fix the circumstances uuder which the solid modification of bromide of vinyl is formed. In some cascs the liquid bromide was pre-served for weeks without the slightest change when suddenly the liquid was found to have been traiisforined throughout its entire mass.At one time I thought I had observed tht the presence of water favoured the metamorphosis but I hmc convinced nipsclf by special experiments that this is not the case. The change takes place as capriciously in the presefice as in the absence of' watcr. It cleserves to be noticed that other bodies derived from ethylene by substitution are prone to similar trsusformations. Thus R e gn au1t * many yeam ago olrmrved analogous pbeiio- men&in the case of dichlorimted ethylcne The reaction generally used for the preparation of this com- pound is so siniple and elegant that it would be difficiilt to propose a better inethod. Indeed all the processes which have been sug- gested differ only as to the proportions of iodine phosphorus and alcohol or as to the manner in wliicli these substances are to be brought into contact with each other.Iodide of ethyl bcing extensively .used as substitution-material in all laboratoricg every observation which is calculated to facilitate the preparation of this body may prove acceptable The common plan of gradually introducing fragnients of phosphorus into the mixture of alcohol and iodine has the disad-vantage of occasionally giving rise to powerful reactions involving considerable loss of materials even when great care is taken to add the pliosphorus slowly and in little fragments. Tliis incon- venieiice may be readily avoided by introducing the phosphorus together with about it fourth of tlie alcohol to be used into a retort connected with an efficient cooler into the tubulus of w'hicli is fitted a glass globe proviclccl with tube and stopcock.-f The rest of the alcohol is then poured upon the iodine and tlie solu-tion thus obtained is introduced through the globe into the retort tvhich is heated on a sand-bath or in a water-bath.Iodine is but sparingly soluble in alcohol but excessively so in iodide of ethyl; it is therefore only necessary to pour thc first portion which distils upon the residuary iodine which is readily dissolved and to allow the concentrated iodine solution thus obtained to flow through the globe into the retort where it is instantaneously converted into iodide of ethyl. This process is especially conve- riient when the iodide of ethyl is to be prepared on a rather large scale.In this case I find it convenient to dissolve the iodine at once in iodide of ethyl and to introduce it slowly through the globe into the retort The stopcock being appropriately adjusted the process requires but little attention and being continuous yields a very large product in a comparatively limited time. The iodide generally distils at once perfectly colourless and requires only to be washed with water in order to become free from traces of alcohol. It deserves to be noticed that the process may be carried out in a very moderate-sized retort since there is only a very limited portion of material at a time under operation. Convenient proportions for iodide of ethyl are 1000 grammes of iodine 700 grammes of alcohol of spec.grav. 0.84 (83 per cent.) and 50 grarnmes of phosphorus. From 96 to 98 per cent. of the theoretical quantity of pure iodide of ethyl are obtained. It deserves to be noticed how small a quantity of phosphorus is necessary for the etherification of the iodine the quantity stated being less than one-half of the amount given in the majority of prescriptions. Iodide of methyl and iodide of amyl may be prepared in the same manner. In the case of iodide of methyl the following proportions have been found by experiment to work well. 1000 grarnmes of iodine 500grammes of methylic alcohol (the fraction boiling below 74*) and 60 grarnmes of phosphorus. The product owing to the volatility of the compound is somewhat less than in the previous case amounting to from 94 to 95 per cent.of the theoretical quantity. 11. On the deportment of Cyanate of Ethyl with Btkykute of Sodium. In a former note* I have stated that cyanate of ethyl when heated with ethylate of sodium is converted into triethylamine and carbonate of sodium. lout I Imve pointed out at the same time that owing to the facility with which the ethylate of sodium Chein. SOC.,(&I. J ,Y 20 undergoes decompasitioii at ’eompnratively moderate temperatures the process in question appeared to be of limited application. I have lately had occasion to resume the study of cyanate of phengl which I described several years ago.* It appeared to me to be af some interest to apply the above reaotion to the prepara-tion of triphenylarnine On performing the experiment I found however that phenylate of sodium and cyanate of plienyl give rise to a different reaction; no triphenylamine was obtained in this process This unexpected result iuduced me to repeat the experiment on the aetion of ethylate of sodium upon cyanate of ethyl.1 have found that in this CaSe likewise the reaction frequently assumes a form different from that which I had previously observed aid which excludes the production of triethylarnine. I am engaged in the study of this transformation the result of which I propose ta lay before the Society on some future occasion. Before the nature of this interesting compound had been finally established by B er the1 ot’ s remarkable inquiries it had been freqqently surmised that the mponification of the several fqtty bpdies which are found in nature did not irivariably furnish the $&mekipd of glycerin.This view appeared to receive nem support in the researches of Wur%ra,who has rendered it probable that glyceriu is but the type of a Glass of homologous triatomic alcohols As a pontribution towards the eluoidation of this question an experiment may be briefly mentioned which arose from a conversa-tiou with my friend Mr. George Fergnson Wilson the technical director of the great establishment well known as Price’$ Patent Candle Company. &Iany hundred weights of glycerin &ga weekly separated in these works by simple steam-saponification from a eoiisiderable variety of fatty bodies ; and My Wilson who has studied with predilection the preparatisn asd purifioation of glycerin on a large scale has acquired a suin of practical information upon this subject such as will not easily be found again.To my question whether there is inore than one kind of glycerin Mr. Wilson replied that in his opinion a11 the fatty bodies wliich he had examined contaiviccl the same * Chem. Soc. Qu. J. ii 363. variety of glyccriii with tlie exception of cocoa-nut oil the g1;tycerin-lilre constituent of which differed iii many respects SO mucli from ordinary glycerin that lie mas inclined to consider it as a special variety. Since this question admitted of a simple experimental solution Xi*. Wilson kindly supplied me with a quantity of glycerin obtained by the saponification of cocoa-nut oil.This substance although prepared iii the same manner differed in colour and odour from the glycerin furnished by other fatty substances. But notwithstanding the colouring matter and an odorous principlc which adhered with great pertinacity it was not difficult to identify the cornponiid under examination with ordinary glycerin. Distilled with iodide of phosphorus it ftxmished iodide of allyl which exhibited the same boiling point as that obtained from ordinary glycerin and was also transformed under the successive irifluence of oxalate of silver and ammonia respectively into oxalate of ally1 and allyl-alcohol. These experiments appear to solve tlie question as far as cocoa-imt oil is concerned. 13. Dinitrotoluic Acid.The nitro-substitutes of the aromatic acids are but slowly transformed into dinitro-compounds. -Whoever has made the experiment in thc benzoyl-series has had an opportunity of experiencing this difficulty. The same remark applies to the toluyl-series Noad,* to whom ~1-eare indebted for the first know- ledge of this group found that nitrotoluic acid may be dissolved in a boiling mixtnre of nitric and sulphuric acids without undergoing any alteratioii. TYhitst studying some reduction plienomeiia of nitro-compounds I felt an interest in procuring if possible a small quantity of dinitrotoluic acid and by my desire Mr. William Temple has prepared this substance. Pure nitrotoluic acid was digested for two days with three times its weight of equal parts of fiming nitric aid sulphuric acids.The solution being mixed with an equal volume of water a crystallization of dinitrotoluic acid was obtained on cooling. It was waslzecl recrystallized from water and sub-mitted to analysis. I. 0.582 grm. of acid burnt with oxide of copper gave 0.908 grm. of carbonic acid and 0.152 grin. of water. * 31~~. C~I,S(C,,111. 43’1 11. 0-396grm. of acid gaye 0.61& grm. of carbonic acid and 0.103 grm. of water. Thebe numbers prove that the acid consisted of dinitrotoluic :reid CbHGN2OG = C,[ll,(N02),10 in 8 state of purity. This result is fully confirmed by the analysis of the silver-salt which is obtained in the form of a white precipitate on addition of aiitrate of silver to a solution of dinitrotohate of ammonium.The silver-salt contains I. 0'609 grm. of silver-salt gave on combustion 0643 grm. of carbonic acid and OW4 grm. of water. 11. 0.130 grm.of silver-salt gave 0.042gvm. of silver. Theory. fi;xperiment. I. 11. c8 96 28-83 28.78 - HEl 5 1-50 1.71 - ATa 0 Ag 28 96 108 8-1,11 23-83 32.43 -__c 1_1 32.30 _. - -/c___ 333 100.00 Few bodies have fixed the attention of chemists more generally than indigo. But have their experiments led to a satisfactory view regarding the nature of this colouring matter ? The brilliant labours of Erdmnnii and of Laurent have brought to light a rich HOFMANN harvest of the most interesting derivatives of indigo but they ham left us in uncertainty with regard to the constitution of this group of eompaunds.With the hope of throwing some light upon this subject 1have endeavoured to eliminate the nitrogen from these compounds by processes likely to act without producing too powerful alterations. The mode o€ action peculiar to nitrous acid appeared to promise some results; and since indigo owing to its insolubility is but little adapted to this reaction I have made some experinients with isatin which is so closely allied to indigo. Supposing isatin to undergo a transformation analogous to that first observed by Piria in similar cases and consisting arithme- tically in the exchange of HN for 0 there appeared some hope of obtaining in this manner iiaphtalic anhydride and of thus open-ing a passage from the indigo-group into the naphtalin-series.Isatiii . . C,€I,N02. Naphtztlic anhydride . C,H,O,. The history of these two bodies prcsents some features which conferred a degree of probability on such a transformation. Both isatin and naphtalic anhydride readily assimilate the ele- ments of water being converted respectively into isatic and naphtalic acids which when submitted to the action of alkalies give both rise to the formation of phenylic derivatives isatic acid yielding phenylamine arid naphtalic acid being converted into hydride of phepyl (benzol) . Experiment however has not confirmed my anticipation and it might seem superfluous to waste another word upon the subject; nevertheless I will briefly mention the result of this unsuccessful experiment since it may probably save some trouble to others.When studying the deportment of isatin with nitrous acid I observed the following facts. If finely powdered isatin be sus-pended in from ten to twenty times its weight of water and the misture be then submitted to the action of a current of nitrous acid (disengaged by the action of arsenious acid upon nitric acid and partially freed from nitric acid by sending it through an empty wash-bottle) the liqliid at once begins to effervesce and the isatin is soon entirely dissolved. The nearly colourless solutioii invariably contains a considerable quantity of nitric acid generated by the contact of the nitrous acid with the water. To avoid the action of this acid upon the product of the transformation of the OX ISATIN.’a5 isatin the liquid mixed Kith much water was evaporated upon the water-bath the water being repeatedly renewed so as to prevent the iiitric acid from getting concentrated. The liquid thus evaporated deposited crystals of an acid which once or twice recrystallized from boiling water appeared to be perfectly pure. On analysis the following numbers mere obtained-I. 0*4305grm. of the acid gave 0.7203 grin. of carbonic acid and 0.1098 grm. of water. IT. 0.3164 grm. of the acid gave 0.5306 grm. of carbonic acid and 0.0874 grm. of water. These numbers lead to the expression which is the formula of nitrosalicylic (indigotic) acid. Theory. Experiment. I. Ir. C 84 45.90 45.60 45.73 H 5 2.73 2-81 2*86 N 14 7.65 -0 so 43.72 -L -c-183 lQO*OO Assuming the iiitrosalicylic acid to be a product of osidatian of the body directly formed from isatin under the influence of uitrous acid the solution before evaporation was neutralized by means of nn alkali.The result remained the same. la another experiment pea-sizcld pieces of marble were introduced into the mixture of water and isatin beEore the iiitrous acid nas passed in order to rcrnove the free nitric acid as rapidly as it mas formed. In these experiments likewise nitrosalicylic acid was obtained. It need scarcely be mentioned that the acid derived from isatin possessed all the properties of nitrosalicylic acid prepared by the ordinary method ;it exhibited more especially the characteristic coloration with perchloride of iron.When the liquid obtained by treatment with nitrous acid was evaporated witliout liaving been previously mixed either with water or with an alkali the isatin as might have been expected was transforniecl into trinitrophenylic acid. This acid was suffi- ciently characterised by its properties and by the aiialysis of its well-known difficultly-soluble potassium-corr_l,onnd. 0.3399grm. of the potassium -salt when buriit with chromatc of lead gave 0.3293 grm. of carhonic acid and 0.0230 grm. of water. The formula CGH,KN,O7 folloving values,-Theory. Experiment. C6 72 26-97 27.14 H2 2 0.75 0.76 I< 39 14-63 -I_ N 42 15.73 0 112 41.95 -Some gtiu-cotton prepared iu. the establishment of Messrs.Hall soon after SchGnbein’s discovery and taken out of a cartridge intended for blasting had been preserved by my friend Dr. Percy since 1847 in a glass bottle provided with a glass stopper. After some time red vapours had appeared in the interior of tlie bottle and thc cotton had crumbled down to a loose powder. When lately the bottle was again examined the powder was found to be converted into a light brown semi-fluid gum-like mass nhile the side of the bottle had become coated with a net-work of fine needles. It was not difficult to collect a sufficient quantity of these crystals ; they exhibited all the chrtrac- ters of oxalic acid. In order to fix their naturc by a number they were converted first into the ainmonium-salt arid then into the silver-salt.0.2420 grm. of silver-salt gave 0.2275 grm of chloride of silver = 70-74p.c. of silver. Oxalate of silver contains 71.05 p.c. of silver. The viscid mass into which the bulk of the gun-cotton had been converted exhibited all the properties of ordinary gum; it was likewise interspersed with crystals of oxalic acid. 16. Expe?*.ime?ztnl ilkstration of tlte Composition of Amrnofaiu iiz Lectures. The deconiposition of ammonia by the spark-current exhibits in a conspicuous manner the condensation which accompanies the transformation of a niixture of liydrogcn and nitrogen iiito ammonia. It is more difficult to illustrate the relative proportion of the nitrogen and hydrogen which exists in ammonia. The €01- lowing experiment elucidates thongh indirectly this relation.A glass tube from 39 to 40 inches in length am1 9 of an inch in width is sealed at one end and divided without particular care into three equal parts which are convcnieiitly marked by papar or by india-rubber rings. The tube is then filled over water with pure clilorine and at once transferred into a test-glass half filled with mercury and half with coScentrated solution of ammonia. Tn this manner a layer of ammonia one or two inches in lreiglit and separated from the bulk of the liquid by mercury is collected in the tube. 1% lively reaction inimediately sets in the mercury rises and thc ammonia-solution floating 011 the metal effervesces with evolution of nitrogen while tlic chloriiie disappesra dense white clouds of chloride o€ammoniuni being formed.According to the equation-II,N + 3c1 = 3HC1 -/-N the 3 volumes of chlorine should be replaced by 1 iiolunie of nitro-gen and this result is actually observed. At the common tern-peratrne hornever the reaction is but slowly accomplished the disengagement of nitrogeir from the solution of ammonia becoming slower and slower but often continuing for hours. On tlre other hand the decomposition is instantaneous if tlie tube be gently inclined and the liquid floating upon the mercury be heated to ebullition. To complete the experiment it is only necessary to transfer the glass tube into a higli cylinder filled with water in which the inner and outer liquids may become level when the 3 volumes of chlorine originally filling the tulle are found to be very accurately replaced by 1 volume of nitrogen gas.Supposing the compositioii by volume of hydrochloric acid to bc known the composition of ammonia is fixed by this observation. The experiment furnishes moreover an instructive illustration of the volnme-ea_ui~ale:ice of cliforine fi yd rogen acd nitrogen HOPMANN ON SEPARATION 17. How to exhibit the hzflarnmability of Anmo~ziic. It is well known that ammoniacal gas cannot be inflamed in atmospheric air but will burn in oxygen gas with a greenish-yellow flame. This flame may be shown by allowing the gas to issue from a bent jet into a vessel containing oxygen. There is however some difficulty in lighting the gas and under the most favourable circumstances the phenomenon is very ephemeral.To avoid this inconvenience the inflamtiinbility of ammonia is gene- rally exhibited by sending a current of the gas into an ordinary flame the ammonia-gas being allowed to issue from the delivery tube into the lower opening of an Argand gas-burner provided with a glass chimney. The gas burning low and almost invisibly the high lainbent ammonia-flame becomes very conspicuous. The phenomenon may however be observed in a purer and much more brilliant form when a vide-mouthed flask containing a strong aqueous solution of ammonia is heated upon a sand-bath and a rapid current of oxygen gas from a gas-holder forced through the boiling liquid. The mixture of oxygen and ammonia-gas thus formed may be lighted and burns at the month of the flask with the characteristic greenish-yellow flame n hich continues until the ammonia is expelled from the liquid.18. Separation of Cadmiumfmua Copper. Having had occasion to perform some experiments on the rela- tive merits of the several processes which have beeii suggested for the separation of cadmium from copper I was led to observe ti property of sulphide of' cadmium which I do not find noticed in analytical manuals. Sulphide of cadmium dissolves with the greatest facility in boiling dilute sulphuric acid which has no effect upon the sulphide of copper. On precipitating by suIphuretted hydrogen a solution containing iiot more than 1 milligrammc of cadmium mixed with 1000 milligrammes of copper and boiling the black precipitate for a few seconds with dilute sulphuric acid (1 part of concentrated sulphuric acid and 5 parts of water) a colourless filtrate is obtained in which an aqueous solution of sulphuretted hydrogen produces an uninistalrable precipitate of yellow sulphide of cadmium.Another solution of the same com-position was mixed with an excess of cyanide of potassium and treated with sulphuretted hydrogen gas. A distinct yellow OF ARSENIC FROM ANTIMONY. coloration was observed a deposit likewise took place but so slowly that; in delicacy the former experiment appears to have a considerable advantage especially since a solution of pure copper in cyanide of potassium also gives rise to b yellow coloration when submitted to the action of sulphuretted hydrogen.19. Separation of Arseizicfrom Antimony. The separation of these two metals which presents uausual difficulties has been a task of predilcction with chemists and a great number of processes have been suggested the majority of which it cannot be denied admit of improvement. Among the many methods the one which is based upon the dissiniilar deport- ment of arsenetted and antimonetted hydrogen with nitrate of silver deserves to be favourably mentioned the former as is well knomn yielding arsenious acid which passes in solution H,As + GAgNO + 2H,Q = OIHNQ + 6Ag + IZAsO,. the latter giving rise to the formation of antimonide of silver H,Sb + 3 Agh'O = 3HN0 + hg,Sb which is insoluble in water. This process presents no difficulty as far as the arsenic is concerned which may be recognieed in solu-tion by ammonia if there be an excess of silver or by sulphuretted hydrogen if the silver has been entirely precipitated.It is far less easy to find according to this process minute quantities of antimony in the presence of large quantities of arsenic the silver- compound of antimony being mixed with a bulky precipitate of metallic silver. By treating this precipitate as might readily suggest itself TI ith hydrochloric acid there dissolves together with antimony a small quantity of chloride of silver which is bufficient to darken the precipitate produced in the solution by sulphuretted hydrogen to such a degree as altogether to mask the presence of antimony. This inconvenience may easily be obviated by boiling the mixture of silver and antimonide of silver after the arsenious acid has been carefully washed out by boiling water with tartaric acid which dissolves the antimony alone.The solution thus obtained yields at once the characteristic orange- yellow precipitate with sulphuretted hydrogen. In some experiments made with the view of testing the delicacy of this process 1 part of antimony in presence of 199 parts of arsenic and %ire verscf 1 part of arsenic together with 199 parts of-antimony could be easily detected. I& cii with minute quan- tities the process proved successful iiiasmuch its S milligramnies of' either metal in the presence of 100 times the amount of the other could be satisfactorily exhibited.In evolving tEic hydrogen.. compoiincls of arsenic and antimony care must be talcen to add as little nitric acid as possible to the liydrocliloric acid USCC~in dis-solving tlic sulphides of the metals since the presence of even moderate quaiititics of this acid greatly iiiterferes with the free disengagement of the gases. If there be tin with the arsenic and antimony this metal will be deposited upon tlie plates of zinc used in evolving the hydrogeii from which it may be meclianically detached dissolved in hydro- chloric acid and tested by the usual processes. The water used for analysis was collected November 11 1858 The water p-inipecl up from the id1 is perfectly clear and colourless and almost inodorous. It has a distinctly saline taste and effervesces on agitation exliiliitiiig the presence of a coild siderable quantity of free carbonic acid.The water contains in addition to carbonic acid a minute trace of' an iiiflarnrnable carbo- netted hydrogen. The presencc of the latter becomes perceptible if a considerable quantity of the water be heated to ebullition and tlie gases expelled be passed through a solutioii of potassa. The gas not absorbed is a mixture of atmospheric air with the car-bonetted hydrogen ;it burns owing to the prepoiiderance of the air with n pale scarcely visible flame. On standing more readily on boiling the water deposits a yellowish sediment consisting of ccrbonate of callcium carbonate of magnesium sesquioxide of iron and organic niatter. Temperature of the water lZ*C tJie temperature of tlie air* being nearly thc same.Specific gravity of the water =l*C06. The analysis was performed iii the usual manner; only tllp determination of the bromine requires a passing notic?. In determining this element I have availed myself of tho method of imperfect precipitation. According to the observn- tions of Lyte and of Field nitrate of silver produces in a mixtiire of chloride bromide and iodide a precipitate first of THE SALINE W-iTER OF CHRISTIAN MALE’ORU. iodide and then of bromide and a precipitate of chloride only after the whole of the iodine and bromine have been separated ;-a method of separating chlorine bromine and iodine based upon this deportment has been proposed by the latter chemist.The amount of iodine present in the watcr of Christian Malford is so exceedingly small that the quaiititative cleterminatioii appeared useless. The task mas therefore limited to the cletermi- nation of the bromine. For this purpose 28 litres of the water ere evaporated to dry-ness and the saliiie residue was exhausted with difnte alcohol. The alcoholic liquid when submitted to distillation left a saline mass which was dissolvecl in a mmll quantity of water. This solution was measured and divided inlr two rqunl parts eneh of which represented the extract of the saline residm of 14 litres = 14084 grarnmes of the original water contaiiiing the vhofe of the bromidcs aid part of tlie chlorides Eacli of the liquids thus obtained mas precipitated by a silver-solution containing 0*4258 grslmmes of pure silver whereby the whole of the bromine and part of the chlorine was thrown down.The ti170 precipitates weighed respectively 0.6355 (I),and 0.6360 (11)grammes. If P represent the weight of the niixecl precipitate and x the amount of chloride of silver in it then P-x is the quantity of bromide of‘silver and if the total amount of the silver in the pre- cipitate be represented by tS then whence S -0.5745 P x = - 0.1781 By substituting the esperimeiital values for X and P in the above expression we find I. IT. Chloride and bromide of silver (by experiment) . . . . 0.6355 0.6350 Chloride of silver (by calcula-lation) . . . . . . . 0.3876 0.3593 Bromide of silver.. . . . 0.2’779 0.2757 Corresponding (in 14084 grms. of water) to bromine . . O*ll82 091273 Or in 1000 grms. to . . . . 0*0084 0.0083 TOL. XITT. < IIOPMANN ANALYSIS OF Direct results of analysis calculated to 1000 grarnmes of water. a. BASES. Experiment. I *. .. 0.0035 0.4234 0.1897 6.9600 0.863 6.097 t. 11. ...... 0.0035 0.4241 0.1903 6.8800 0.897 6.983 Mean.. , 0.0035 0.4238 0.1900 6.9200 0.880 6.040 b ACIDS (or denzents replacing them) Sulplinric Rromine Carbonic Carbonic Acid comliineit Carbonic Chlorine. trg:ofSilica. hid fi ee as Carbonate of EXP. anil Calcium. Acid. Iodine. combined. on3 Magnesium. Acid free. __I__.----.i. .... 0.2464 4.5630 0 *0084 0 -0150 0 *2921 0 -1050 0 1871 IT. ....0-2452 4 -5570 0.0083 0 -0145 0 *3164 0 *lo72 0 2092 Mean ,. 0.2458 4 -5600 0 *0084 0 +0148 0 -3043 0,1061 0,1982 c. RESIDUE LEFT ON EVAPORATION. Experiment. Mineral Residue. Organic Matter. Total Residue. I. ....*... a -2000 0 *0200 a -2200 JI. ........ 8*1900 0 *0200 a *2100 ---.I-----nifean ,.,. . . 8,1950 0 -0200 8 -2150 THE SALINE WATER OF CHRISTIAN MALE’ORD. VERIFICATIONS. a. VERIFICATION FOR LIME. __ .-__ -Lie precipitated Lime left in solutiou on after Total Total Experiment. ebullition. ebullition. bY bjr (Carbonate of (Sulphateand Chloride Calculation. Experwept Calcium.) of Calcium.) I-I I. . . ,. . . 0.1285 0-2895 IT. ...... 0 *1307 0.2556 0 -4163 0,4241 Mean ,. .. 0 -1296 0 ‘28’76 0,4172 0,4238 6.‘VERIFICATION FOB MAGNESIA Experiment. Magnesia ebullition. (Carbonate of Magnesium.) precipitated 011 Magnesia left in solution (Chloride after ebullition. of Magnesium ) Total Calculation.by Fatal Experiment.by ------___I I. ......I 0.0022 I 0.1852 1 0.1814 I 0.1897 11. ..*... 0 ‘0025 0 *1863 0 *1888 0 -1903 --_I_--- Mean ,. .. 0,0024 0 -1857 0 ~1881 0.1900 SALINECONSTITUENTS. In one gallon In 1000 grammea (70,000grains) of water. of water. _. _. Grammes. Grains. Su’fphnteof calcium . . 0.4179 29.253 Cmbonate of calcium . . 0.2314 16.198 Chloride of calcium . . 0.2289 16.023 Carbonate of magnesium . . 0.0050 0.350 Chloride of magnesium . . 0.4413 30.891 Bromide of magnesium (with traces of iodide of magnesium) 0-0096 0.672 Carbonate of iron .0.0051 0.35if Chloride of potassium . . 043800 61.600 Chloride of sodium . 6*0400 422*800 Silica . 0.0148 1.036 Organic matter . . 00200 1-400 8,2940 580.580 G2 The water contains 29-03 cubic inches in the gallon 01' 104.6 cubic centimetres in the litre of free carbonic scid. Tlic quantity of carbonic acid was determined at the well. It deserves to be mentioned that the water for this purpose was pumped up whereby probably a minute quantity of gas was lost. My thanks are due to Mr. 33 Millar of Christian Malford for his help in collecting the water and to Dr Leibius for his assist- ance in pe~forr~ing the experiments. 21. SpontaneousDeconposition of Chloride of Lime One morning (I think it was in the summer of.' ZSSS) when entering my labor:itory which I had left in perfect order on the px*evious evcning I was surprised to find the room in the greatdst confxxsion.Broken bottles and fragiue11ts of apparatus lay about several window panes mere smashed and all the tables and shelves were covered mitli a dense layer of white dust. The latter was soon found to be chloride of lime and ftirnished without difficulty the explanation of this strange appearance. At the conclusion of the Great Esliihition of 1851 31. Ktihl-rnann of Lille had made me rz present of the splendid collection of cheinical preparations mliich he had contributed. The beautiful large bottles were for a long time kept as a collection; gradually however tlieir contents prored too grezt a temptation and in the course of time all the substances had-been consumed.only one large bottle of about 20 litrcs capacity and filled with chloride of lime had rcsisted all attacks; the stopper had stuck so fast that nobody could get it out ; and after many unsuccessful efforts-no one rcnturing to indulge in strong measures with the handsonic vessel-the bottle had at last found a place on one of the highest shelves of.' the laboratory where for years it had remained lost in dust and oblivion until it had forced itself back on our recollection by so energetic an appeal. The explosion had been so violent that the neck of the bottle was projected into the area where it was found with the stopper still firmly cemented into it. I have not been able to learn mlrether similar cases of the spontaneous decomposition of chloride of lime have been already observcd.CARBON LN COAL GAS 22 Bisukhide of Cnrbon iiz CoaE Gas. It is well known that coal gas even when submitted to the most improved processes of purificntion retains a minute quantity of a sulphur-compound which yields sulphurous acid mhcn thc gas is burned. A commission having been appointed fur the purpose of rcportings to the Lords of the Committee of Privy Council on Education on the lighting of picture-galleries by gas and on any precautions (if necessary) against the escape of gi1s and of the products of its combustion the writer of this note undertook a few experiiiicnts with the view of determining the amount of sulphur generally present in the London coal gas.The object of the inquiry being to ascertain the quantity of sulphurous acid capable of being formed by the combustion of the gas an exceedingly small jet of gas carefully washed with acetate of lead-which showed the absence of sulphuretted hydrogen- and measured by au accurate experimental meter wits burned in a large two-necked glass globe. Through one of the necks the gas tube was conveyed into the globe whilst the other fitting iiito a condenser carried off the product of combustion into a two-necked receiver. To establish a current of air tlie receiver was eorinected with a water-current aspirator a couple of Woolfe's bottles containing water or dilute ammonia being inserted for the pur-pose of fixing any trace of sulphurous acid wliich might escape condensation with the water in the receiver.The experiment being terminated the liquids in the receiver and in the mash- bottles were uuited oxidized with chlorine and precipitated with chloride of barium. Experinients in July 1859. Order of Experiments. 1. .. . . . 1-98 0 0630 0 -437 6 -74 15 433 11. ....*. 2 0 0840 0 *577 8 -90 20 371 111. . .... 2 0 *0630 0 '433 6 *68 15.278 IT.,.,... 2 0 -0i40 0 *508 7 84 17 -944 t, Mean ..,. .. 1 0 488 7 -54 I7 *256 * Rcport on the subject of Liglitiiig Picture Gallerics by Gae by Professors Faraday Nofmsnn,and Tyuclsll Ah licdgrave R.A and Capt. ft'owke R,E. HOFMANX OX ‘YHE Experiments in December 1859 and January 1860.Order of Experiments. Amount of Snlpliiirin 100 cubic feet. Graiiis. 1 -Grammes. v. .... TI.,... 0 *osso 0-0953 0 *611 0 *654 9 *43 10 -10 21,585 23 -111 VIT. ,. . . VIII. . . 0*0975 0*0935 0 -669 0-642 10*33 9 91 23 644 22 *677 _I_-- Mean .,, .. 0-64.1 9 *94 22,754 I These experiments show that the amount of sulphur remaining in the Londoh gas after the removal of the sulphuretted hydrogen is very small and that in winter it is somewhat greater than in summer. This may possibly arise from the enormously increased production of gas during the winter months when it will be more difficult to regulate the several processes involved in its manufac- ture. But the result may also be purely accidental arising from a change in the nature of the coal used etc.A much more extended series of experiments would be required to decide this question. It has long been assumed that the sulphur in purified gas exists in the form of bisulphide of carbon the conditions for the genera- tion of this compound being in fact given in the ordinary process of producing gas. That coal gas really contains bisul- phide of carbon was first elegantly proved by Vogel,* who at the suggestion of Baron Liebig passed a current of purified gas through an alcoholic solution of potassa when xanthate (sulpho- carbonate) of potassium (K(C,H,)CS,O) mas formed which pro- duced in copper-solutions the highly characteristic yellow precipi- tate of xanhate of copper and yielded when boiled with a few drops of nitrate of lead in the presence of free potassa a black deposit of sulphide of lead.When engaged in the above inquiry I repeated Vogel’s experiments which I can confirm in every parti- cular. The amount of hisulphide of carbon in the London gas is however so small that a very large volume must be passed through the alcoholic solution of potassa in order to produce a sufficient quantity of xanthate of potassium. After a cubic foot of gas had been passed through alcoholic potassa in a bulb apparatus the * L i e big’s Annaleri Ixxxviii 369. C€IANGES OF GUTTA PERCI-1.4. solution gave with sulphate of copper a leek-green precipitate in which the presence of xanthate was but imperfectly indicated. Only after passing several additional cubic feet the yellow colour became more distinct although still masked to stlme extent by the hydrated protoxyde simultaneously precipitated.On the other hand the black precipitate of sulphide of lead mas obtained without difficulty even after the passage of one single cubic foot of gas. But the presence of bisulphide of carbon in coal gas may be es- hibited even more elegantly and with greater precision by means of trie~~~~~os~~ine, which produces with the bisulphide a com-pound crystallizing in splendid prisms of a ruby colour. This body is so characteristic and forms with so much facility that biswlphide of carbon has become a most valuable re-agent for triethylphosphine and its homologues. The idea naturally sug-gested itself to employ the phosphorous-base for the detection of bisulphide of carbon in gas.On distilling a considerable proportion of coal -gas-benzol I had separately collected a small fraction which came over in the commencement below 65O. When mixed with triethylphosphine this liquid solidified into a mass of the well known ruby crystals. Four or five drops of triethylphosphine were dissolved in ether the ethereal liquid was introduced into a bulb apparatus and a current of coal gas allowed to bubble through the solution. When 0.2 of a cubic foot had passed the liquid had assumed a distinctly red coloration the intensity of which increased as the passage of the gas and the evaporation of the ether continued. After 0.8 of si cubic foot had pawed the whole of the ether had evaporated and the inaer surface of the bulb-apparatus was lined with a beautiful network of the ruby crystals 28.Remarks on the Changes of Gutta Pwcha under ‘Tropical TnfEuences. [From & Report addressed to Sir W. B. O’Shaughnesay Director-General of Telegraphs in India.] The peculiar change which gutta perclia undergoes when in contact with air for some time is well known this substance gradually becoming brittle and ultimately losing all coherence. T’his effect was experienced on an undesirable scale in conatruct- ing the East Indian Telegraplis. Enormous qurtiitities of gutta percha bccame in a comparatively short time entirely useless involving a loss of thousands of pounds. At the request of Sir W. B. O'Shaughnessy I have made a few experiments with the gutta percha thus altcrcd the results of which were recalled to my mind by tIic researches on the alteration of gutta percha lately published by Oudeman.It may be of some interest briefly to inention the analytical results furnished by the chauged material submitted to me for examination. The specimcns sent home from India formed a brown exceed- ingly brittle substance softening to a plastic moss in boiling water. Since the gutta percha existing in commerce does not always exhibit the same characters it was of some importance for the inquiry that a quantity of the original unchanged substance with vhich the wires sent out to India had been coated was likewise placed at my disposal. In their deportment with solvents the changed and unchanged gutta percha exhibited a marked difference.Whilst the latter proved to be pzrfectly insoluble in strong alcohol the changed gutta percha was in a great measure taken up by this solvent. By treating the changed material first with cold then with boiling alcohol and ultimately with ether three substames were obtained which aithough very much alike in their physical properties differed considerably from each other in their chemical composition. T.-Szcbstance soluble in cold Alcohol. Cold alcohol readily attacked the outer surface of the coating and dissolved a coiisiderable portion. On evaporation a brown resinous mass remained behind which ,was dried first over sul- phuric acid and ultiinately at 100"; at wliich temperature it readily fused.*The fused mass solidified on cooling to a brittle substance yielding a highly clectrical powder and exhibiting on combustion the following percentage composition I. 11. Mean. Carbon. . . . 62.941 62-64! 62.79 Hydrogen . . 9.22 9-36 9.29 Oxygen . . . 27.84 28.00 27.92 -7- I c\o*oo 1 OU~OO 100.00 IT.-Substance soluble in boiling A7cohol. By treating with boiling alcohol the residue of the previous operation which had ceased to yield anything more to cold alcohol a fiesh quantity of substance was obtained in solution. The alcoholic liquid on evaporation left a residue very similar to that of the previous operation which when dried in the same manner furnished on analysis the following numbers.I. 11. Mean. a b Carbon . 68.13 67.29 67.72 Hydrogen. . 10.01 10.18 10.09 Oxygen. . . . 21.86 22.53 22.19 100*0O 100~00 100*00 111.-Substance insoluble in coEd and in boiling Alcohol. The residue left after repeated treatment with boiling alcohol dissolved in ether a few mechanical impurities remtiining behind. The ethereal solution gave vith alcohol a precipitate which dried ’up to a yellowish powder becoming highly electrical by trituration and caking when gently heated. It had the general characters of gutta percha being merely somewhat deeper coloured and less plastic. When analysed it furnished numbers nearly agreeing with those which were obtained by several observers for gutta percha Carbon . . 88.12 Hydrogen .12*39 The body last analysed mas obviously unchanged gutta percha; a view which is also supported by its soluliility in chloroform and benzol. The substance in question differed from specimens of gutta percha investigated by others and espccidly from that which Payen coiisiders the pure gutta percha by its solubility in ether The original substance with which the wires had been coated was however likewise soluble in ether. It cannot therefore be doubted that gutta percha exists in several modifications. The experiments which I have qnoted prove that the changes which gutta percha undergoes in contact with air depend upon oxidation. Unchanged gutta percha is free from oxygen; the product dissolved by cold alcohol contained nearly 28 per cent.HOFIh4NN ON THE CHAX'GES OF GUTTA PERCHA. and that soluble in boiling alcohol still more than 22 per cent. of oxygen. 1 need not mention that I am far from believing that these oxygenated substances are definite chemical compounds. Their mode of preparation altogether precludes such an idea the object of the experiments having been simply to establish the fact of oxidation having taken place. That the changes of gutta percha are due to the absorption of oxygen is countenanced by the expe- rience of this substance having been lrept for years under water without undergoing any alteration.