摘要:

THE QUARTERLY JOURNAL 0El THE CHEMICAL SOCIETY VII.-On some Compounds 01 Iodide and Bromide of Mercury with the Alkaloids. BY THOMAS B. GROVES,F.C.S. WEYMOUTH. I BEG leave to direct thc attention of the Chemical Society to a class of compounds that I believe has not hitherto been noticed and which I think deserves attention as likely to afford materials whose investigation may throw additional light on that gomewhat obscure but highly interesting subject the Alkaloids. The compounds in question are €or the most part crystalline. Their composition is represented by the empirical formula (Hg I, Alk.) and (Hg Br, Alk.). (Hg.=100 and Alk. represent- ing morphine codeine strychnine quinine cinchonine &c.) I first observed the reaction that led to this investigation on adding to a solution of iodide of mercury in iodide of potassium a small quantity of hydrochlorate of morphia.A bulky white pre- cipitate was formed which when tested revealed the presence of mercury iodine and morphia and was then found to be crystal- lisable from alcohol and water. Morphine I observed was not the only alkaloid liahle to this reaction but that all the alkaloids proper I had access to viz. VOL. XI. H GROVES ON quinine cinchonine codeine veratrine aconitine brucine and strychnine also narcotine and a similar body I have separated from the capsule of the English poppy and termed diacodine were equally so. Salicine and aloine however were unaffected. The iodide of potassium and mercury may therefore be regarded as a general precipitant of the alkaloids; and seeing that these com- pounds are nearly if not entirely insoluble in cold water and have a high atomic number I conceive they may be aclvantage- ously applied to the determination of their atomic numbers and ah be highly useful in medico-legal investigations.I append the individual characters of a few of the combinations containing iodine. That of morphine is soluble to a small extent in boiling water especially if slightly acidulated and separates in the crystalline form on cooling. It dissolves much more rcadily in hot alcohol. That of quinine is almost perfectly insoluble in boiling water but dissolves in almost any proportion in boiling alcohol from which the greater part again separates as a soft resinous mass on cooling.When however the cold solution is allowed sponta- neously to evaporate it crystallises beautifully. That of cinchoniire behaves very similarly. Its crystalline character is however something different as also its solubility. These two last are both fusible at about 200° and when cold are very brittle with conchoidal fracture. That of strychnine is insoluble to any appreciable extent either in hot or cold water and dissolves very sparingly in boiling alcohol. From this it crystallizes in a triangular form. The crystals are quite microscopic very brilliant and make good polariscope objects. That of codeine is soluble in and crystallizes from hot water and alcohol I think more freely than any that I have observed.That of bruciiie is slightly soluble in water and generally less refractory than that of strychnine ; and like it becomes gritty soon after precipitation. The others I need not particularise as they have offered no details of interest. None of them as far as I have observcd contain water of crystallisation Their crystalline form is usually acicular with I think in most cases a triangular section. They are not decomposed by dilute acids cold or hot or by IODIDE AND BROMIDE OF MERCURY. iodide of potassium and are only affected by Boiling solutions of the fixed alkalies. In obtaining them for the purpose of analysis I have precipitated one equivalent of the alkaloid by a solution of three equivalents of iodide or bromide of potassium and one equivalent of chloride of mercury.I have not been able to produce a corresponding ammonia com- pound. Their analysis was effected :-(1.) By dissolving a carefully dried and weighed quantity in boiling alcohol and adding thereto an ex- cess of recently prepared sulphide of ammonium to precipitate the mercury as HgS. The heat is kept up 'a few minutes to avoid the precipitation of the compound by the cooling agency of the reagent; a slight excess of nitric acid added and the sulphide of mercury separated and v-eighed in the usual manner. From the filtrate deprived of sulphretted hydrogen by the cautious ap- plication of heat the iodine is thrown down by nitrate of silver and the alkaloid is estimated by difference.(2.) By precipitating first the iodine by nitrate of silver re- moving the excess of the precipitant by hydrochloric acid and then as before. (3.) The strychnine salt which could not be got into convenient solution was digested for half-an-hour with sulphide of ammonium and then treated as before. When caustic potass is added after the sulphide the sulphide of mercury is dissolved by the sulphide of potassium formed and the liquid is immediately filled with crystals of strychnine fully +th of an inch long. In no case have I directly estimated the alkaloid. The concur- rence of the analyses I doubtless owe to the ready and complete desiccation of the compounds. The following are the results of analyses of the iodine compounds of morphine and strychnine which appear to justify the formula I have ascribed to them within the limits of error :-Analyses of the Morphine Salt.-No.1. Calculation. Analysis. NO. l.-Hg,=Z00 2-04! 2-617 I =381 3.88 3.636 Morphia =285 2*91 3-177 -866 8.83 8.830 H2 100 GROVES ON CaIculation. Analysis. NO.2.-Hg2 = 200 1.57 1.543 I,=381 3.00 2.820 Morphia= 285 2.25 2.45 7 866 6-82 6.820 Centesimal Comparison. No. 1. No. a. Mercury=22.85 = 22.63 Todine=41-18 = 41.35 Morphia= 35-97 = 36-02 1UO~OO 1oo*oo Analyses of the Strychnine Salt. No. f.-Hg2= 200 2.99 3.155 1,=381 5-71 5.996 Strychnine= 334 5m00 4.549 915 13.70 13.700 2nd Analysis of the Strychnine Salt. Calculation. Analysis. Hg =2OO 2.19 2-267 I =281 4-19 4.486 Strychnine= 338 3868 3-307 915 10.06 10.060 Centesimal Comparison.No. 1. No. 2. Mercury. . =23*03 = 22.54 Iodine . . =43.77 = 44.59 Strychnine= 33.20 =32.87 100*00 1@0*00 On submitting however the compounds of quinine and cincho-nine to the same treatment I was annoyed to find a very consider-able discrepancy which I first thought was occasioned by defect of drying; but this having been proved not to have been the case I IODIDE AND BROMIDE OF MERCURY. considered it just possible that the compound I had analysed (the amorphous mass deposited by the cooling of its alcoholic solution) had been rendered basic by the action of the solvent; that the crystals obtained from the mother liquor were possibly acid and the first precipitate neutral.Samples of each of these were carefully analysed and the results obtained were identical. Cinchonine was found to present the same difficulty both yielding about as much of their respective alkaloids as would be expected were their equivalents one-fourth less than they are believed to be. Thus-Analysis of the Quinine Salt. Calculation. Analysis. NO.1.-Hg =200 3-66 3.82 I =381 6.96 7.70 Quinine =324 5-93 5.03 905 16-55 16-55 NO.2.-Hg2=200 1.302 1-38 I,=381 2.479 2.75 Quinine =324 .%lo9 1.76 -205 5.890 5-89 Centesimal Comparison. No. 1. No. 2. Mercury =23.08 =23.43 Iodine. . =46*52 =46.69 Quinine =30.40 =29.88 1oo*oo 100*00 Analyses of the Cinchonine Salt. Calculation.Andysia. NO.1.-Hg2=200 3.39 3.62 1,=381 6.47 7-16 Cinchonine =308 5.23 4.31 8-89 15-09 15-09 102 GROVES,. ON IODIDE AND BROMIDE OF MERCURY. 2nd Analysis of the Cinchonine Salt. Calculation. Analysis. Hg,= 200 1.70 1-80 I,=381 3.26 3-55 Cinchonine=308 2-64 2.25 889 7.60 7.60 Cent esim a1 Cornparison. No. 1. No. 2. Mercury. . =23.99 =23-69 Iodine .. =4’7-45 =46.71 Cinchonine =28.56 =29:60 100.00 100*00 Taking these facts in connection with the anomalies experienced by Dr. Bir-d Herapath in his late experiments on his interest- ing discoveries the iodo-sulphates of the cinchona alkaloids (“ Pharmaceutical Journal,” March 1858) and more especially since the equivalents of Dr. Her ap at h approach somewhat nearly those I have referred to I would venture to suggest whether it would not be advisable to re-open this question by thoroughly investigating Dr.He rap at h’s iodo-sulphates in connection with the double iodides. I will here just observe in conclusion that the iodide of mercury and potassium was suggested by Dr. de Vry as a precipitant for strychnine ; the knowledge that it is not specially so will prevent dangerous possibilities. I have also suggested the use of the com- pounds as internal remedies in cases where the simultaneous exhi- bition of mercury iodine and some alkaloid is indicated and they are now undergoing a trial at the hand< of several Weymouth practitioners.

ISSN:1743-6893    

DOI:10.1039/QJ8591100097

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年代:1859

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103 VIK-On a new method of preparipg Prwpionic Acid :vix. hy the action of Carborcic acid upma an EthyE compound. By J. A. WANKLYN, Esq. IN the course of experiments made on the action of highly electro-positive metals upon zinc-ethyl I obtained some time ago crystalline compounds containing the metal employed in union with ethyl. These bodies of which a detailed account will shortly be published react most energetically upon bodies containing an electro-negative constituent. Such indeed is the electro-positive energy of the sodium com-pound that dry carbonic acid itself is thereby decomposed with evolution of heat the resulting product as will further on be proved being propionate of soda. I proceed to describe the experiments with carbonic acid and the new body containing ethyl and sodium.Sodium-ethyl* was prepared by acting upon zinc-ethyl with sodium whereby metallic zinc was precipitated and a crystalline compound containing sodium-ethyl and zinc-ethyl was podnced. This body which dissolved readily in excess of zinc-ethyl was introduced into a bulb so constructed as to admit of the passage of a gas. On attempting to free the crystalline compound from adherent zinc-ethyl by the transmission of carbonic acid great evolution of heat occurred zinc-ethyl distilled off and the contents of the bulb formed an amorphous white solid. This latter effer- vesced with water forming a solution which when treated with sulphuric acid evolved the odour of propionic acid. In proof that this heating and solidifying were due neither to free oxygen nor to moisture I may mention that an experiment was made with the same apparatus in which hydrogen was substituted for carbonic acid and that no such effects occurred as had been noted in the former case.Different samples of sodium-ethyl prepared from zinc-ethyl as aforesaid were exposed to the action of carbonic acid. In one case the subsequent treatment of the amorphous solid was as follows:-it was put into water distilled with dilute * Sodium-ethyl cannot be obtained by the action of sodium upon iodide of ethyl. siilphuric acid and the distillate subsequently redistilled alone in order to separate anything which might have been mechanically carried over during the first distillation.The second distillate containing the dilute pure acid was warmed with carbonate of baryta filtered and evaporated to dryness in the water-bath. The residue which was crystalline and completely solublc in water mas afterwards dried in the air-bath at about 13OOC ;until it no longer lost weight. A baryta determination-made by moistening the salt with strong sulphuric acid and afterwards igniting cautiously to expel the excess of sulphuric acid and the organic matter gave this result--288grm. of the substance yielded *237grm. of sulphate of baryta. The substance therefore contained 48.38 per cent. of barium. Propionate of baryta contains 48.41 per cent. of barium. From another sample of sodium-ethyl the amorphous mass given by the action of carbonic acid was treated thus :-First with a little moist ether whose purity had been well ascertained.The object of this deviation from the plan followed in the former case was to avoid a troublesome elevation of temperature which occurs when zinc-ethyl (adherent to the propionate of soda) is suddenly acted upon with water. After the addition of water and the expulsion of the ether which had been added by heating in the water-bath a distillation with dilute sulphuric acid was made as before. The distillate after supersaturation with carbonate of soda was evaporated to dryness in the water-bath; and an endeavour was made to obtain concentrated propionic acid from this soda-salt by distillation with strong sulphuric acid. This operation was care- fully conducted in the air-bath the materials being contained in a small bulb retort.Neither carbonization nor evolution of sul-phurous acid was observed and the resulting distillate had the smell of propionic acid. From it a silver-salt was made by the use of pure oxide of silver. This salt forming beautiful but exceedingly light crystals was crystallised by cooling its solution in hot water. The crgstals were separated from the mother-liquid and dried in vacuo. I. 00466grm. of the substance gave OH cautious ignition *Of272 grm. of nietallic silver. TI. A combustion was made by heating the substance placed in PROPIONIC ACID. a small platinum boat in a stream of dry air freed from carbonic acid. The products of combustion were led over red-hot oxide of copper and in fact the arrangement was essentially the same as that which gives remarkably accurate results in the hands of Hofmann and others.So treated -0632grm. of the substance gave -0447 grrn. of carbonic acid. -0154 grm. of water. ,0377 grm of silver. Here follow the collected results compared with the com-position of propionate of silver. Propionate of Silver. Calculated Found. ..____JL_c? I. TI. C 36 19.89 -19-29 H5 5 2.76 -2.71 0 32 17.68 -18.35 Ag 108 59.67 58.4 59.65 181 100.00 100~00 The reaction which takes place between carbonic acid and sodium-ethyl admits therefore of the following expression :-Propionate of Soda. C2 O4 + Na C H5 = C 0 C H 2 4N;}o2 And since there can be no doubt that homologous bodies would give analogous results with carbonic acid-that for instance sodium-methyl would give acetate of soda-we may write the following as a general formula expressing the reaction which has been realized.Inspection of the formula will at once show that a synthesis exactly corresponding to the well-known and beautiful analysis of the series of volatile fatty acids '2 '2 'n Hn+& } 0 made by Kolbe some years ago has now been effected. In fact such a reaction as that described here is what that distirrguished chemist in conjunction with Frankland predicted in his memoir' of last year. * Ann. Ch. Pharm. ci. 2G5. 106

ISSN:1743-6893    

DOI:10.1039/QJ8591100103

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年代:1859

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106 IX.-Notice of another New Maximum and Minimum Mercurial Thermometer. BY JOHNG. MACVICAR, D.D. Moffat. THEmaximum and minimum thermometer described by me at page 221,volume x of this journal is not the only one in which mercury may be used to give the minimum as well as the masi- mum for any interval of time between two successive adjustments. A rnoie elegant instrument at least for meteorological purposes may be constructed thus :-Let a mercurial maximum thermometer of the ordinary Ruther- ford's construction be taken and let 50" or 60' in length of a suitable liquid be introduced into the stem immediately above the mercury and into this liquid let two indices be inserted first one which shall obey the magnet as in Rutherford's maxirniim ther- mometer and then one ol' enamel as in Rutherford's minimum.Let the instrument be then sealed in the usual may and on the plate let two scales be engraved one taking its points from the top of the mercury for a scale of maximum temperatures and the other taking its points from the top of the liquid for a scale of minimum temperatures and the instrument is completed. To prepare for an observation let the enamel index be brought as in Rutherford's minimum to the top of the liqiiid; then holding or placing the instrument horizontally let the steel index be brought by the mag-net to the top of the mercury. The thermometer is now fit for use. It is obvious that the upper end of the enamel index will give the minimum and the lower end of the steel index the maxi- mum temperature since the last adjustment.I had contrived this instrument before that described at page 221 volume x but passed from it at the time in apprehension of not finding a liquid suitable for the suspension of the minimum index. Spirit and azlalogous liquids tend to dlffuse with the mer- ATOMIC t7rEIG;RTS OF OXYGEN AND WATER. 107 cury when in a horizontal column and each breaks the continuity of the other. And thoiigh when this occurs the instrument still remains a good mercurial minimum yet it destroys its complete- ness and beauty. I am now satisfied however that a liquid having no diffusive tendency or chemical action between it and mercury as also a sufficiently low freezing point and high boiling point may be found.In fact between twenty and thirty years ago Mr. Adie the opti- cian in Edinburgh merely to prevent oxidation in the tubes of Rutherford’s maximum thermometer introduced above the mer-cury naphtha ;and I saw the other day one of these thermometers which during that long interval had preserved the mercurial column unbroken and the steel index pure and all right. It is certain however that it is not every kind of liquid that passes in commerce under the name of naphtha that will do so. But the fact that a hydrocarbon was found which has continued to function well for a quarter of a century shows that a suitable liquid may be foulrd. Residing however as1 do among the mountains of Scotland far away from all facilities for accurate experiments I must leave further determinations to those who are more favourably situated for such enquiries.

ISSN:1743-6893    

DOI:10.1039/QJ8591100106

出版商:RSC    

年代:1859

数据来源: RSC

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ATOMIC t7rEIG;RTS OF OXYGEN AND WATER. 107 X.-On the Atomic Weights of Oxygen and Watei.." BY WILLIAM ODLING,M.B. SECRETABY TO THE CBEhfICAL SOCIETY. WHETHER an atom of water contains the same quantity or double the quantity of hydrogen that is corttained in an atom of hydro-chloric acid and whether the atomic weight of oxygen is 8 or 16 are concrete examples of the many disputed questions which lie at the very basis,of scientific chemistry. These many prirnary ques- tions are so intimately connected with one another that if the answer to nearly any one of them were fully agreed upon that * Extract from a lectiire ''On dtoms Mplecules and Equivalents," delivered April 15 and May 6 1858. 108 ODLING ON THE single unanimity might almost determine an entire unanimity.But to arrive at such a desirable consummation it is neces-sary for some one or other of these questions to be fairly argued out upon premises that are admitted by all to be indis- putable. And herein lies the great difficulty because in reality each one of us has formed his opinion upon the single ques- tion rather by its bearings upon all the other disputed ques-tions than from well defined premises of any kind. Mach party has assumed instinctively certain points that are not proven or are disallowed and from these assumptions has deduced in great measure his conclusion upon all the questions. Moreover to no one question can there be given an answer the correctness of which is proveable to demonstration. Almost every fact may be interpreted in several different ways; and it becomes an argu- ment from probability from analogy from simplicity from come- qnences as to which interpretation is most exact.But apart from the absolute accuracy or falsity of any explanation it is evidently most inconsequent to interpret as many chemists do a certain set of facts in one special manner and a precisely similar set of facts in an opposite manner. Now it is to this time-honoured inconsistency that I wish particularly to direct your attention. Allow me for a few moments to occupy your time with such an elementary introduction to the doctrine of combination in definite proportions as we might all agree to put before a student commencing the study of chemistry. Thus we are acquainted with about sixty different kinds of matter which have hitherto proved unclecomposable and which we consequently term simple bodies or elements.These elements unite with one another in certain fixed or definite proportions to form an infinite variety of compound bodies. We can illustrate our meaning very well by reference to hydrogen Chlorine and sodium ; three elements that are possessed of highly character- istic properties. We find by experiment that 1part of hydrogen unites with 35.5 parts of chlorine to form the compound body chloride of hydrogen or chlorhyilric acid; and that 35.5 parts of chlorine unite with 23 parts of sodium to form the compound body chloride of sodium or common salt. We take the numbers 1 35.5 and 23 to represent the combining proportions of hydro-gen chlorine and sodium respectively and in a similar manner there have been assigned to other of the elements certain num- bers which express respectively the least proportion of the ele- ATO.MiC WEIGHTS OF OXYGEN AND WATEK.rnent that unites with 1 part of hydrogen,-or that replaces 1 part of hydrogen to unite with 35.5 parts of chlorine. Thus 3595 parts of chlorine or 19 parts of fluorine, 1 part of hydrogen unites with or 80 parts of bromine or 127 parts of iodine and 1 part of hydrogen 7 or 23 parts of sodium unite with 35.5 parts of chloriiie. or 32.5 parts of zinc or 108 parts of silver J The proportion in which hydrogen enters into a combination being less than that of any other element is assumed as unity; and as the quantity of sodium or zinc or silver that displaces 1 part of hydrogen from its combination with 35.5 parts of chlorine also displaces it from its combination with 19 parts of fluorine or with 80 parts of bromine or with 127 parts of iodine it is evident that the numbers 1,19 23,32.5 35.5 80,108 and 127 indicate generally the proportions in which the elements hydro- gen fluorine sodium zinc chlorine bromine silver and iodine unite with one another.The above proportional numbers result from a common well defined relation to the standard of compari-son; they are mere results of experiment uncontrolled by any theory whatever. So far as we have yet gone our idea of the combining proportion of an element is the least quantity of the element that can unite with or replace 1 part of hydrogen.But this simple idea has very speedily to receive an important modification. We find the smallest quantity of nitrogen that can unite with 1part of hydrogen to be 4.7 parts but the corn-bining proportion of nitrogen is fixed not at 4.7 parts but at three times that quantity or 14 parts. We find that 1part of hydrogen unites with 35.5 parts of chlorine to form the com- pound chlorhydric acid and that one part of hydrogen unites with 4-7 parts of nitrogen to form the compound ammonia. We take 35.5 as the proportional number for chlorine why do we not take 4.7as the proportional number for nitrogen? Why do we not express the compound body ammonia by the formula HN precisely as we express the compound body chlorhydric acid by the formula HCl? To avoid the confusion that would arise from using the same letter to express two different quantities we will take the symbol Az to represent 4.7 parts of nitrogen; so that ODLING ON THE 3 HAz = H,N.Now the formula HAz is in accordance with all the considerations hitherto presented to our notice it is more simple than the formula H,N and by its mcans ammoniacal com- pounds in general might be represented as analogous to chlorine and fluorine cornpounds j thus Ammonia .. .. 13Az HC1 Trizincamide .. .. ZnAz ZnCl Trimercuramide .. HgAz HgCl Potassamide .. .* KAz.2HAz KCl.2HgCl Sal- ammoniac .. HC1.3HAz KI. 3HgC1. Why then have chemists unanimously rejected the formula HAz and adopted the formula H,N ? Now although this last formula may have originated in part from accident and have been retained in part from habit yet we have no lack of real arguments to show the necessity or at any rate advisability of maintaining it.I believe the principal arguments are the following :-lo.Because it is found that a given bulk of gaseous ammonia contains three times as much hydrogen as the same bulk of chlorhydric acid. 2". Because it is found that a given bulk of nitrogen combines with three times as much hydrogen as does the same bulk of chlo-rine; and that the relative weights of equal bulks of nitrogen and chlorine and hydrogen are as 14 :35.5 1. 3'. Because certain undoubted analogies and ratios of nitro-genised bodies are concealed by formule in which Az=4*7 and are manifested by formulae in which N=l4.4". Because in ninety-nine cases out of a hundred the quantity of ammonia which is the agent or resultant of a reaction must contain three units of hydrogen or some multiple of three units of hydrogen; and consequently fourteen or some multiple of fourteen parts of nitrogen. 5". Because in the majority of the compounds which ammonia forms with other bodies the ammonia must be represented with three units or some multiple of three units of hydrogen. 6". Because although the composition of some few nitrogenised bodies may be repreFented most simply by formulae in which Az=4*7; yet the great majority are represented most simply by formuh in which N =14.7". Because in ammonia the actual or potential replacement of hydrogen takes place definitely in thirds by three successive stages. Although the above arguments cannot be considered to prove AlOAIIC WEIGHTS Ok' OXYGEN AND WATER. 111 absolutely to demonstration that the atom of nitrogen or the smallest indivisible quantity of nitrogen that can enter into B corn-bination is really fourteen times as great as the atom of hydro-gen yet they present so great a sum of probabilities in favour of that conclusion that chemists have been unanimous in accepting it. With one exception all these arguments apply with equal force to the elements phosphorus arsenic antimony and bismuth ; and we consequently find that all chemists have agreed to accept for the respective atomic weights of these bodies three times the smallest quantity of the body which unites with 1 part of hydro pen or with 35.5 parts of chlorine.The excepted argument is that relat- ing to the vapour densities of the elements in question. But in default of this argument we can bring forward another of a most cogent nature in behalf of the triplication of the atomic weights of phosphorus arsenic antimony and bismuth namely that derived from their gradational analogies to nitrogen. I€the atomic weight of nitrogen is 14 and not 4.7 the atomic weights of phosphorus arsenic antimony and bismuth must be respectively 31 75 12C5 and 213 and not the thirds of these numbers. From the above considerations concerning nitrogen and its con- geners in which all chemists are agreed it appears that while the determination of the smallest proporbionof an element that can unite .with or replace one part of hydrogen is a question purely experi-mental the determination of the atomic weight of an element or of the smallest indivisible quantity of an element that can enter into a combination is a question for the judgment and one that can only be decided by an intimate knowledge and due cousidera- tion of very many circumstances connected with the body.Now although the judgment of chemists has been unanimous with re-spect to nitrogen and its congeners such unanimity has not pre- vailed in reference to many other elements. Thus with regard to silicon Th om son represented chloride of silicon by the formula Si C1 wherz the atomic weight of silicon = 7-12 G meli n by the formula Si Cl, where the atomic weight of silicon=l4.25 Berzelius by the formula Si Cl, where the atomic weight of &con=21-37 Whereas in my opinion the balance of argument is in favour of the formula Si Cl, where the atomic weight of silicon=28.50 112 ODLINQ ON THE In reference to a body of such doubtful analogies as silicon whose combinations moreover are remarkable for their complexity it is fit and natural that differences of opinion with regard to its atomic weight should be entertained by different chemists according to their particular modes of viewing the subject; and not only with regard to silicon but to boron to gold to uranium to tantalum and indeed to all elements the analogies of which have not been well established.Rut in reference to such well known elements as oxygen sulphur and carbon there certainly ought to be the same unanimity that obtains in the case of nitrogeu; though in reality we find the discord even more violent than in the case of silicon. The majority of English chemists represent the atomic weight of carbon by 6 that of oxygen by 8 and that of sulphur by 16. Dr. Frankland would double the atomic weight of carbon but would retain the old atomic weights of oxygen and sulphur. Mr. Griffin who lays claim to priority in doubling the atomic weights of carbon and oxygen ridicules the notion of doubling that of sulphur. Dr. Williamson Mr. Brodie and myself have for a long time past advocated the doubling of all three.Let us now proceed to investigate from undisputed data the atomic weight of oxygen and of its most important compound with hydrogen namely water. Is the atom of water HO=9 or H@= 18? All chemists admit firstly that the atom of chlorhydric acid con- sists of 1 part of hydrogen united with 35.5 parts of chlorine; secondly that the atom of ammonia consists of 3 parts of hydrogen upited with 14 parts of nitrogen; and that as compared with 35.5 parts of chlorine 14 parts of nitrogen is the smallest quantity of nitrogen that can enter into a combination. Now I wish to show firstly that if the atom of chlorhydric acid consists of 1 part of' hydrogen united with 35.5 parts of chlorine and if the atom of ammonia consists of 3 parts of hydrogen united with 14 parts of nitrogen then the atom of water must consist of 2 parts of hydrogen united with 16parts of oxygen ;secondly that if 35.5 parts of chlorine constitute the smallest indivisible quantity of chlorine tlrat can enter into a combination and if 14 parts of nitrogen con- stitute the smallest indivisible quantity of nitrogen that can enter into a combination then 16 parts of oxygen constitute the smallest indivisible quantity of oxygen that can enter into a combination; or in other words that the atomic weight of oxygen is 16 when ATOMIC WEIGHTS OF OXYGEN AND WATER.compared with the atomic weight of hydrogen as I of chlorine as 35.5 and of nitrogen as 14.Every argument that induces us to accord to the atom of nitrogen the number 14 rather than the number 4.7 should also induce us to accord to the atom of oxygen the number 16 rather than the number 8. I propose to review briefly all the arguments we hme admitted in the case of nitrogen and to prove that they are equally applica- ble in the case of oxygen; or to show why it is that ammonia must be written H,N and water H,8 as compared with chlor- hydric acid IIC1. NITROGEN. OXYGEN. a. Because it is found that a a. Because it is fGund that a given bulk of gaseous ammouia given bulk of gaseous water ron-contains three times as much tains twice as much hydrogen as hydrogen as the same bulk of the same bulk of chlorhyilric chlorhy dric acid. acid./3. Because it is found that a /3. Because it is found that a given bulk of nitrogen combines given bulk of oxygen combines with three times as much hydro- with twice as mzich hydrogen as gen as does the same bulk of does the same bulk of chlorine ; chlorine and that the relative and that the relative weights of weight of equal bulks ojnitrogen equal bulks of oxygen and of and of chlorine are as 14 to chlorine are as 16 to 35.5. 36.5. I attach very great importance to these first two arguments which applymitli equal force to the duplication of oxygen and the triplication of nitrogen ; to the binhydric character of water and the terhydric character of ammonia. y. Because certain undoubted y. Because certain undoubted analogies and ratios of nitro-analogies and ratios of oxidised genised bodies are concealed by bodies are concealed by formula? formule in which Az= 4.7 and in which 0=8 and are mani- are manvested by formule in fested by formula! in which which N= 14.0-16. These reasons apply with about equal force though in a some-what different manner to nitrogen and to oxygen respcctively. Thus with Az=4*7 the analogies of nitrogen and chlorine com- pounds would be concealed by the formulte for we shoiild have-%OL. XI. I ODLTNG ON THE Nitrous acid. Chlorous acid. HAz,Q instead of HNQ analagous to HCW,. Nitric acid. Chloric acid. HAz30 instead of HNQ3 analagous to HClCI,. Pernitric oxide. Perchloric oxide. Az60* instead of N2Q4analagous to Cl@,. With 0= 8 the relation of water to the alcohols as the undoubted vanishing point of the series would not be manifested as it is in the formulze with c1= 16.Thus if me write alcohol C4H602 wood spirit C,H,O, and water HO the relation of water to the alcohols does not appear but in the following series of formulze it is perfectly apparent :-G5H1,Q Amylic alcohol. G3HIoQ Butylic , G3H80 Propylic , GzH6 U Ethylic , .6 H 8 Methylic , H Q Hydric , The relation of water to the alcohols as shown in the above formulae is not a mere paper relation but has its foundation in experiment. When alcohol and water respectively are acted upon by potassium by chloride of benzoyl by pentachloride of phos-phorus and by a host of other re-agents the reactions are acknowledged by all to be precisely parallel.All chemists no matter what formulae they employ recognise the fact that the quantity of water which in a reaction corresponds to one propor-tion of alcohol must contain two units of hydrogen. Similarly with regard to the hydrated bases and acids. If we write hydrate of potass KHO, hydrated hypochlorous acid HClO, and water HO the relation of the formulze as representing comparable quantities does not appear. But in the following series it is perfectly evident :-K K 43 Potass oxide. K H U Potass hydrate. H IT # Water. H C18 Hypochlorous acid. K C1 Q Potass hypochlorite. C1 C1 .c1 Hgpochlorous anhydride. ATOMIC WEIGHTS OF OXYGEN AND WATER. 115 The following reactions among many others show that the quantity of water which corresponds to one proportion of hydrate of potass or of hypochlorous acid must contain two units of hydrogen :-1.Action of Chloride of Benxoyl. KHO+G,H,ClQ=KCl +eyH6Q2' H,8+G7H5Cl€J= HCl +c,H6a2. 2. Action of Chlorine. KHB+ C1 = HC1Q + KC1. H2Q+ el2=HClQ + HC1. 6. Because in ninety -nine 6. Because in ninety -nine cases out of a hundred the cases out of a hundred the quantity of ammonia which is quantity of water which is the the agent or resultant of a re-agent or resultant of a reaction action must contain H3 or some must contain H, or some mul- multiple of H,; and conse-tiple of H,; and consequently quently 14 or some multiple of 16 or some mult$le of 16parts 14parts of nitrogen. of oxygen.This argument is one of the most cogent that can be adduced. It is well illustrated in the case of nitrogenized but infinitely better in the case of oxidised compounds. Let u9 adduce some uitrogenous react ions. 1. Formation of Ammonia from Xal Arnmoniac. NH,Cl+CaHB =NH +CaCl+H,B; or Az3H,C1 + CaH02= Az3H3+ CaCl -+ H,02. 2. Formation of Ammonia from Nitrate of Potass. KNQ3+8H=KH8 +NH +2H2Q; or ~Az306+8~=KH0,+Az,H,+4H0. 3.Formation of Cyanogenfrom Uxalate of Ammonia. 2NH3..6,H2Q4 -4H28=f2.6N; or 2Az3H3.C4H,08-8H 0=2C2Az ; or Az,H,.C,H 0,-4H 0= C2Az3. ODLING ON THE Express the above reactions howsoever you please you cannot represent any one of them with a proportion of ammonia contain- ing less than 3 units of hydrogen nor consequently with less than 14 parts of nitrogen.And whenever morc than 3 units of hydrogen are required you must take some multiple of three units of hydrogen and some multiple of 14 parts of nitrogen; and ninety- nine cases out of a hundred will yield the same result. As an example of those cases in which it is possible to represent the acting or resulting proportion of ammonia with less than three units of hydrogen I may adduce the- 5. Formation of Triethylamine. NH +3G2H,I=N.3C2H,+3HI; or Az,H +3C411,1=3AzC4H +3HI; or Az H + C,H,I= AzC,H,+HT. And similarly with trirriercuramine NI-Ig3= 3 AzHg ;though no one really thinks of writing the formuh of these bodies with only one unit of ethyl or of mercury respectively. Let us now revert to oxygenous reactions.I wish to show that in ninety-nine cases out of a hundred where water appears as the agent or resultant of a reaction it is impossible to represent that water with less than two atoms of hydrogen. lo. Whenever an alcohol ketone or other oxidised organic coin-pound yields a hydrocarbon by dehydration the water eliminated contains two or some multiple of two units of hydrogen. 1. Formation of Olefiant Gasfrom Alcohol. C,H6~-H2Q=G21-14; or C4H602-2H0 =C4H,. 3. Formatton of Cymene from Camphor. GloHlsQ-EI,&J =G10H14 ; or CzoHI60,-2IIO =C,,Hl,. Other compounds than hydrocarbons result from similar eqm? tions thus- ATOMIC WElGHTS OF OXYGEN AKD WATEK. 4. Formation of Acrolein from Glycerin. .6,HsB3-22H2Q=G3H48 j or C6H806 -4H0 =C6H,02.2" Whenever an organic acid yields a pyroacid or other pyro-genous product by dehydration :-1. Formation of Carhonic Oxide from Formic Acid. GH2Q2-H2Q=W ; or C2H20,-2HO= C20,. 2. Formation of Maleic from Malic Acid. G4H6Q5-H28=C4H4Q4; or C,H60,,-2H0 =C,H,08. 3. Formation of Pyruvic from Tartaric Acid. G4H686-H2B-M2=G3H4Q3; Or CSH60,,-2HO -2CO2=C6H4O,. 4. Formation of Aconitic,from Citric Acid. G6H8Q -H28=.6,H686; or C12H,0,4 -2H0 =C12H6012. 5. Formation of Pyromucic,from Muck Acid. C6H1,Q -3H28-&$ =C5H4U3; Or C1,H1,016- 6H0 -2CO2=C10H406. 3>.Whenever two compounds act upon one another to form a new compound with simultaneous elimination of water. ODLING ON THE 3.Kitro-naphthaline. HN8 +clOEi -H2Q=GloHp(XQ,) HNO +C,,H -ZHO =C2,H7 (NO4) Action of an Acid upon an Alcohol. 4. Phosphovinic Acid. H3P8,+C,H@ -H2Q=H2 (G2H5) PB,; or H,PO +C,H602-ZHO =H (C,H,) PO,. 5 Benxoic Edher. C7H@ +G2H@ -H,B=G,H5.G7H,8 ; C,,H604 +C4H602 -2HO=C,H5.C14H50,. 7. Nitraniline. HNG +G6 H,N-H2Q=G6 H (NQ,) N ; HNO6+C12H7N-2HO=C,,H6 (NO,) N. Action of an Acid upon an Acid. 8. Nitrosalicylic Acid. HNB,+C H6Q3-H,CS=C7 H5 (N8,) 03 ; HN06+Cl4H6O6-2HO =C14H5(NO,) 0,. Action of an Acid upon an Aldehyd. 9. Nitro-benzoic Aldehyd. HN83+C7 H6Q -H28=G7 H (N02) Q ; or HNO +C14H602-2H0 =C14H5 (NO,) 0,. Action of an Alkali upon an Aldehyd. 10. Hydrobenzamide. 2NH 3e7H@ -3H20=c21 H,,Na ; or 2NH,+3Cl,H60,-6H O=C,,H,,N, ATOMIC WEIGHTS OF OXYGEN AND WATER.119 4'. Whenever a salt of ammonia aniline or other volatile alkali loses water. 1. Formation of Cyanhydric Acid. NH,.CH20 -ZH28=C N.H; or NII,.C,H,O -4HO =C,N.H. 2. Formution of Benzanilide. c6 H7N.G7 H6Q2-H20=c6 H6 (e,H5@)N ; or C12H,N.C,,H60 -2HO=Cl,H6 (C1,H,02) N. 3. Formation of Aceto-nitrile. NH3 aCzH482 -ZH2Q =62H,N NH3.C4H40 -4H0 =C4H3N In all the illustrations hitherto brought forward the water has been the resultant of the reaction. Many of these reactions are capable of being reversed and the water then appears as the agent of the reaction. But we can also adduce an abundance of other and most varied instances in which water is the agent of a reaction. 1. Decomposition of Hippuric Acid.ggH,NQ3+H,Q=C H6Q2+C,H,N8,; or C,,HgN06 +2HO=C,,H60 +C4H,N04. 2. Decomposition of Pentachloride of Phosphorus. PCI +H,Q= PBCI +2 HC1; or PCl +2HO =P02C13+2HC1. 3. Decomposition of Chloride of Benzoyl. C7 H5ClQ-F H2Q=.6 H6Q2 +HC1; or C14H5CI02+ZHO = C14H6044-HCl. 4. Decomposition of Zinc-ethyl. G2H,Zn+ H243=.6,H6-t ZnHQ ; or C4H,Zn +ZHO= C4H6 +ZnHO,. The circumstance that 2HO are invariably associated is strongly suggestive of their being inseparably associated of their constitut ing in fact but one atom. 120 ODLXNG ON THE 6. Because in the majority of e. Because in the majority the compounds which nmmonia of the coinpumds which wutter forms with other bodies the ma-forms with other bodies the monia must be represented with water must be represented with three units or some multiple of two units or some multiple of three units of hpdrogen.two units of hydrogen. We may take aldehyd-ammonia G,H,B,.NH, and ammofiiacal sulphate of zinc Zn2S0 .4NH, as nitrogenous illustrations. The oxygerious illustrations are innumerable including nearly all cases of water of crystallization We may take as examples :- Fructose .. Gt3H12Q6; or cI,H 120 12' Glucose .. .66H12~6.H,~ or Cl,H120,2.2H0. ; Destrine .. WWh or c12H10010' Lactine .. G6HloU5.H2CT; or C12Hl,01,.2H0. ; or C,,HI6.6HO. Hydrate of' turpentine ~10~~16.3H28 Hydrate of alloxan G4 H2 N,.Cs,.FI2c) ; or C,H2N,0,.2H0. y. Because although the c Because although the formule of some Jew nitrogen- formule of some few oxidized ized bodies may be represented bodies may be represented most most simply byformulce in which simply by formulce in which Az =4-7,yet the great majority 0=8 yet the great majority are represented most simply by are represented most simply by formula.in which N= 14. formule in which 8=16. This argument applies strongly in the case of nitrogenized but much more strongly in the case of oxydized compounds. Ammonia and all derivatives of ammonia in which the whole of the hydrogen is replaced by one single kind of' metal or hydro-carbon or haloid might be represented more simply by formuh in which Az=4.7 than by formulae in which N=l4 Thus triethylaniinc is written most simply Az G2H5 though most cor-rectly by N 3G2H,.I believe that all other nitrogenized bodies are necessarily rcpresented most simply by formulz in which N= 14. With regard to oxygen all hydrated oxides double oxides hydrated acids oxy-salts aldehyds ketones alcohols pseudo- saline ethers and various other descriptions of compounds doubt- ATOMIC WEIGHTS OF OXYGEN AND WATER. I21 less forming together 99 per cent. of all known compounds of oxygen cannot be represented so simply by formulze in which 0=8 as by formulae in which /\= 16. I have contended that if the comparable atoms of nitrogenized bodies were correctly formulated they would all of them be repre- sented more simply by formulae in which N =14 than by formuh in which Az=4-7; and I now contend that if the comparable atoms of oxidized bodies were correctly formulated they would all be represented more simply by formulae in which @=16 than by formulae in which 0=8.But precisely as there are some few nitrogenized bodies which with the symbol Az=4i7 may be divided into thirds and can thus receive simpler formulae than with the symbol N=14 so are there some comparatively few oxidized bodies which with the symbol 0=8 may be divided into halves and can thus receive simpler formulae than with the symbol Q= 16. These bodies are the following :-lo.Most compounds in which oxygen is united with one kind of matter only including nearly all the simple metallic oxides. Thus with 0=16 water and lime must be written respectively H,4 and Ca,Q analogous to hydrate of lime CaHB; but with 0=8 they may be written thus-H,O and Ca202 analogous to hydrate of lime CaHO,; or thus-HO and CaO.T do not propose to argue the point whether CaO or Ca202(= Ca20) is tlie correct expression for a metallic oxide lime; any more than I have argued the point whether HgAz or Hg,Az (=Hg,N) is the correct expression for a metallic nitride mercuramine. We are at present discussiug whether the formula of water is HO or H,O (= H2Q,) and the decision upon this point will determine that of the metallic and other simple oxides. It may be observed however that many strictly cornparable reactions can be effected by means of lime hydrate of lime and water respectively and that in these cases we always require 2H0 or 2Ca0 to effect the reaction. Of course if Ca,O is the correct expression for the atom of lime the formula with Q=16 is simpler than that with 0=8 and similarly with other homogeneous oxides.2O. Bodies analogous to ordinary ether and the homogeneous anhydrides. With 0=16 ether and benzoic anhydride must be written respectively- Et,Q analogous to H Et 8 and MeEt c) Ether. Alcohol Methyl-ethyl-ether ; 122 ODLING ON THE and Bz,B analogous to H Bz Q and Ot Bz 8 Benz-anhydride. Benzoic acid 0thyl-benz-anhydride; but with 0=8 they may be written thus :-Et 0 analogous to H Et 0 and Me Et 0,; and Bz 0 analogous to H Bz 0 and Ot Bz 0,; or thus :-Et 0 and Bz 0. Now all arguments founded on mode of formation on reactions on vapour-densities on seriated position and properties &c.tend to show that EtO and BzO are not correct expressions of the nature of the bodies represented;++ and if Et,02 and Bz,Oz are the correct expressions it is at once eviderit that in these cases formulae with 0=16 are simpler than formulae with 0=8. 30. Certain acids and their salts of one metal heretofore usually considered monobasic but which in reality are bibasic. Thus with .8=16 the hydrated carbonic sulphurous and sulphuric acids must be represented respectively by the formulae :-H24=3 H2w3 J32=** But with 0=8 they may be represented thus H2C206 H2S206 H,S,OS ; Or thus HCO HSO HSO,. But in these cases we can adduce strong evidence to show that the simple formulae HCO, HSO, and HSO, are not correct ex-pressions of the nature of tlie bodies; and if the correct expres- sions are H2C206 H,S,06 and H2S208 that is to say if the acids are bibasic then the formulae with 8=16 are evidently more simple than those with 0=8.We shall presently advert to the distinctions between monobasic and bibasic acids. * I mean to say that ether by its mode of formation and chemical reactions by its vapour density and other physical properties belongs to the following series of strictly comparable substances and that its formula is not C H 0 but c H 0 4 5J 8 10 2 =c4~,,@, wide Williamson Journal of Chemical Society vol. iv. Vinic Et1hei.s. H 0. C4H50 H . G2H5Q Hydro-ethylic. C H 0. C4H50 f2 H . G2H.58 Methyl-ethylic. C H 0. C,H50 G2H5 . G2H,8 Ethyl-ethylic. c'16 H 0. C,€150 G3H .G2H,8 Yropyl-ethylic. C H 0. C4H50 G4H . G2H5Q Butyl-ethylic. C,,H,,O. C,H50 G5Hile G2H58 Amyl-ethylic. ATOMIC WEIGHTS OF OXYGEN AND WATER. actual or potential replacement tual or potential replacement of hydrogen takes place de$-of hydrogen takes place dej- nifely in thirds by three SUC-nitely in halves by two suc-cessive stages. cessive stages. i We have no definite nitride that can be represented as ammonia in which one-half the hydrogen is replaced as we might expect if the atomic weight of nitrogen were 4.7. We have no definite oxide that can be represented as water in which one-third the hydrogen is replaced as we might expect if the atomic weight of oxygen were 8. Thus Chloride. Oxide. Nitride. KC1 KO HAz KC1.HgCl KO.HO Wanting KC1.2HgC1 Wanting HAz.2PtAz If we write water N we at once see the H necessity or reason for the vacancies. In water me can replace a half but not a third. In ammonia we can replace one-third or two-thirds but not a half; whereas in marsh gas H replace one-fourth two-fourths or three-fourths but not one-third or two-thirds of the hydrogen. We are acquainted with many amrnonias in which 1 2 and 3 thirds of the hydrogen are replaced such for instance as NH,K Potassamide NHI Biniodamide NHg Triinercuramine But the most striking illustration of replacement by thirds is afforded by Hofrnann’s researches on the volatile alkaloids in which he successively replaced 1 2 and 3 atoms of hydrogen by a mere continuation of one and the same process.Ammonia. Ethylia. Diethylia Triethylia. aniline. ODLING ON THE We are acquainted with many oxides that may be considered as derivatives of water in which one half the hydrogen is replaced or in which both halves are replaced by different elements or groupings. Thus Water. Alcohol. Ether. Methyl-ether. Phenyl-ether. Ethylate of potw. Hydrate Oxide Zinc oxide Hypochlorite Hypochlorous Hypochlorous of potass. of potass. of potass. of potus. acid. anhydride. In many cases we can effect the total replacement by the same element or grouping at two successive stages. Thus Water and potassium yield Q {z Hydrate of potass Hydrate of potass and iodide of ethyl 0 {it yield Alcohol Alcohol and potassium yield 0 (E" Ethylate of potass Ethylate of potass and iodide of ethyl a {:: Ether yield Ethylate of potass and iodide of methyl (Eelll'Iethylateof ethyl yield Hydrate of potass and potassium yield -(r Oxide of potass.-E This brings to a conclusion my arguments upon the atomic weights of oxygen and water founded on a comparison of the arguments which apply in the case of nitrogen and ammonia. The point that I urge is not so much the absolute point namely that the atomic weight of oxygen must be 16 as the relative point namely that if the atomic weight of nitrogen is 14 and not 4.7 125 ATOMIC WEIGHTS OF OXYGEN AND WATER. the atomic weight of oxygen must be 16 and not 8. Every argu- ment that applies to the first case applies with equal if not greater force to the second.T know very well that some of the argu- ments I have adduced as that from analogy for instance may be apparently subverted by the subterfuge of writing water H202; but I also know that chemists who make use of the formula H202to represent water act most inconsistently if they do not also make use of the formiike H,Az to represent ammonia. There are three consequent methods of formulating chlorh-ydric acid water and ammonia in respect to one another namely I. 11. HC1 HC1 HO H202 HAz H3Az3 The first method was that employed by Dalton who wrote ammonia Om=1+ 5 and water 00=1+‘7. But both the following modes are most inconsequent and therefore reprehensible :-IV. V. HC1= 2 vol. HC1 =2 1701.HO = 1vol. H20,=2 vol. H3N= 2 vol. H3N=2 vol. Series IV. represents irrelative quantities and series V. accords irrelative formuh to cornparable quantities. I would observe in reference to series I. II. and IIT. that the selection of one or other of them involves both a question of fact and a question of convenience. Whether the first or the second series really repre- sents comparable quantities that is to say whether the atom of water or the smallest proportion of water that is the agent or re-sultant of a reaction contains twice as much hydrogen as the atom or smallest reacting and resulting proportion of hydrochloric acid is a question of fact. Whether the formula in the second or that in the third series is the most appropriate mode of ex-pressing the fact may be to some extent at least a question of convenience though at the same time it is one of very consider- able importance.The same remarks apply to the formulz for ammonia. But we have an additional arguinent iu favour of the duplication of the atom of oxygen derived from the series into which it ODLTNG ON THE enters. Thus in all compounds of oxygen with two other kinds of matter as particularly instanced by ox-acids and oxy-salts the oxygen increases by 16 parts; and in none of these compounds can we add subtract or replace a less quantity than 16 parts of oxygen. Why this should be unless the 16 parts constitute an indivisible proportion or chemical atom I am at a loss to con-ceive. The following are illustrations :-Chlor-hpdric acid ...* .. HC1 or HC1 Hypochlorous acid .. .. HClQ or HC10 Chlorous acid . . .. .. HCW or HClO Chloric acid .. .. .. HClG or ~~10 Perchloric acid .. .. .. HClQ or HC10 Phosphuretted hydrogen ,. .. H3P or H3P Chlorophosphoric aldehyd .. CI3P8 or C13P02 Hypophosphorous acid Phosphorous acid . . Phosphoric acid .. .. *. .. .. .. .. H3PQ3 H3PQ4 H3p82 or H3P04 or H3POG or H,PO Ethylene .. .. .. H4.c=2 or H4C4 Aldehy d .. .. .. H&@ or H4C 0 Acetic acid .. .. .. H4G2u2 or H4C,04 Glycolic acid . .. .. H4W3 or H,C406 Chloride of carbon .. .. C12G or C12C Phosgene .. .. .. Cl2a or Cl,C,O Formic acid .. .. .. H2-2 or H2C204 Carbonic acid {hydrated) . . .. H24=3 or H2C206 Precisely as the triplication of nitrogen necessarily leads to the triplication of phosphorus and its cougeners so must the duplica- tion of oxygen lead to the duplication of sulphur and its con- geners.Every argument that applies to the duplication of oxygen applies with almost equal force to ihe duplication of sulphur even that argument derived from the combinink volume of sulphur vapour provided the researches of Bineau are trustworthy. One important consequence arises from the duplication of the atomic weight of sulphur namely the necessary representation of the sulphurous and sulphuric acids as bibasic. Now the question of basity is a purely experimental one. If we find the sulphurous ATOMIC WEIGHTS OF OXYGEN AND WATER. and sulphuric acids to have the properties of bibasic acids we have a strong corroboration of the high atomic weights of sulphur and oxygen.But if we should find the sulphurous and sulphuric acids to have the properties of monobasic acids that single cir- cumstance would be of itself almost sufficient to discredit the view which accords to oxygen sulphur the atomic weight 32. I. Certain oxacids have the following pro- perties :-a. Each of them can form bat one kind of ether. This is neutral in its properties. Within two volumes of its vapour there is contained bzct one volume of ethyl or alco- hol residue. p. Each of them can form a chloride or rather chloraldehyd within two volumes of the vapour of which is contained but one volume of chlorine. Each chloral-dehyd can exchange chlorine for peroxide of hydrogen to reform the normal acid bnt there is not any compound interme- diate between the chlomldehyd and the normal acid.y.. Each of them by reacting with am- monia can form bzct olae primary amide. This is neutral in its properties. 6. They cannot any of them form stable well-defined acid salts or salts with two or more metallic bases. 6. They cannot any of them form the atomic weight 16 and to TI. Certain other oxacids have the follow- ing properties :-a. Each of them can form two ethers the one neutral the other acid; for ex-ample sulphatic ether and sulpho-vinic acid. Within two volumes of the neutral ether there are contained two volumes of alcohol residne. B. Each of them can form a chloral-dehyd within two volumes of the vapour of which are contained two volumes of chlorine.These chloraldehyds can each exchange chlorine for peroxide of hydro- gen to reform the normal acid ; but there is a compound intermediate between the chloraldehyd and the normal acid so that the conversion may be effected at two successive stages. Thns chloro-sulphuric aldehyd can produce first chlorhydro-sul pliuric acid and then normal sidphuric acid. y Each of them by reacting with am-monia can form two primary amides the one neutral the other acid; for example sulphamide and sulphamic acid. 8. Each of them canform st,able well- defined acid salts exactly intermediate in composition between the neutral salt and the free acid such for instance as the bisulphate of potass.Each of them can form well defined double salts in which either one-half or one-fourth the basic hydrogen is replaced by a basylous metal the quantity of reacting acid however being twice as great in the second case as in the first. Common alum is an ex- ample of the second variety potass-sul- phate of nickel an example of the first The acids of this class moreover produce various ill defined hybrid salts in which the basic hydrogen of the acid is replaced by an indefinite number of metals in in-definite proportions. E. Each of thein caN form double 128 ODLING double or multiple ethers that is ethers with two or more varieties of alcohol residue. (. They carmot any of them form double or multiple amides that is amides with two or more varieties of aniuioniacal residue.7. They cannot any of them form etheramides or compounds containing both alcoholic and aminoniacal residues. 8. They cannot any of them form coni- plex acids by reacting with hydrocarbons. 1. As a general rule the acids of this class are more volatile than those of the succeeding classes while their salts are more soluble. They very rarely yield anhydrides by direct dehydration or forin anhydro-salts. They do not forin distinct varieties of salts such as have received the prefixes para- nieta- iso- &c. Acids which have the properties described mi- der the above heads are classed as matzo-basic acids. K. It is observable that when a mono-basic acid reacts upon another monobasic acid to form a new acid by the elimina- tion of water the new acid has also the properties of a monobasic acid; for ex-ample nitro-benzoic acid.ON TIIE ethers that is ethers with two varieties of alcohol rcsiduc in equal proportions; for example the double sulphxte of ethyl and methyl the double carbonate of ethyl and amyl &c. (. Each of them culz forin double amides that is amides wi,h two varieties of ammoniacal residue in equal propor-tions ;for example anilo-sulphamide or anilo-carbamicle. v. Each of them can form double ctheraniidcs that is compounds with an alcoholic and an aminoniacal residue in equal proportions ; for example sulplla- methane or sulphamethylane.8. Each of them can forin complex acids by reactkg with hydrocarbons ;for example the sulpho-benzidic and sulph- ethylenic acids. I. As a peiieral rule the acids of this class are less volatile than those of the preceding class while their salts are less soluble They yield anhydrides by direct dehydration;they form anhydro-salts and also distinct varieties of salts such as have rwcived the prefixes para- inch- iso- &c. Acids which haw the properties described iinder the above heads are classed 3s bibasic acids. K. It is observable that when a bibn- sic acid reacts upon a monobasic acid to form a new acid by the eliminat,ion of water the new acid has also the proper- ties of a bibasic acid ;for exaiiiplc sulpho-benzoic acid.There are many other distinctions between the two classes of acids but the above are the most important. Sulphurous and sulphuric acids therefore are considered to be bibasic simply because they are possessed of certain properties which arc charac- teristic of bibasic acids without any reference whatever to their formulze. The circumstance of their bibasity as far as it goes is in favour of the duplication of the atoms of sulphur and oxygen from which such bibasity follows as a necessary consequence inas- much as with these high atomic weights it is impossible to repre- sent the acids as being other than bibasic. With 0=8 and S=16 the formulze for the bibasic acids would be H,S,O and H2S208respectively than which the formulze H2SQ3and H2SQ are evidently more simple.Moreover we are thus enabled to formulate two natural series of acids. ATOMIC WEIGHTS OF OXYGEN AND WATER. Chloric HCQ FIClO Perchloric Sulphurous H,W H2SQ4 Sulphuric Phosphorous H,PQ H,PO Phosphoric The properties of tribasic and quadribasic are as well defined as are those of bibasic acids. Thus a tribasic acid can form three ethers two of them acid and one neutral. Also a chloraldehyd which within two volumes of vapour contains three volumes of chlorine. Also three amides two of them acid and one neutral. Also acid and double and treble salts in which the hydrogen and bases are related to one another by thirds. Also treble ethers treble amides treble etheramides &c. &c. In reference also to the basity of sulphuric acid I might start from another point and show by parallel arguments that for every property of phosphoric acid which causes it to be recognized as tribasic there is a similar property of sulphuric acid which must cause it to be considered as bibasic precisely as I have shown that the accord- ance of a terhydric character to ammonia necessitates the accord- ance of bi-hydric character to water.With regard to the duplication of carbon it is found that car- bonic and sulpho-carbonic salts have bibasic properties and must consequently be written HMC,06 &f,c,06,M,C,S6 &c. Also that the smallest quantities of carbonic oxide carbonic anhydride and sulpho-carbonic anhydride that are the agents or resultants of reactions contain twice the quantity of substance usually repre- sented by their respective formuh; or in other words that their real formulz are C,O, C20, and C,S,.By making these few alterations all compounds of carbon become formulated with an even number of carbon-atoms so that nothing is easier than to substitute one large carbon atom G having the value 12 for two small carbon atoms C having each the value 6. In this way the anomaly of the increment of carbon in homologous series always taking place by two inseparable atoms is done away with as is also the anomaly of the atomic heat of carbon.

ISSN:1743-6893    

DOI:10.1039/QJ8591100107

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

130 HERGPATH ON THE XI.-& the Geizeral Characters of the lodo-Sulphates of the Cinchona-AAaloids. BY W. BIRDHERBPATH M.D. F.R.S.E. IN a paper recently presented to the Royal Society entitled “Researches on the Cinchona Alkaloids,” the author has hail tlie honour of communicating the discovery of a class of‘salts analogous to the sulphate of iodo-quinine first described in the Phil. Mag. March 1852 and the crystallography of which was subsequently more fully elicited in a paper which appeared in the Proceedings of the Royal Society vol. vi. The optical and chemical characters of these remarkable new bodies present many points of striking similarity; yet a careful examination will disclose differences more especially in their optical properties sufficient to iriduce the author to propose the foimation of these optical salts as a means of recognizing each of the cinchona alkaloids or as a method of ascertaining their purity for which and for a complete description of these beautiful compounds the author begs to refer to his original paper or to the abstract of the 2nd part read at the Royal Society Nov.126 ultimo. In the present communication only a brief abstract of the principal optical properties will be given so as to enable each salt to be recognised and the general chemical characters of the class will be enumerated; but the main object of the present paper is the communicatio~i of the details of the author’s analytical results obtained in his investigations; from which he has been led to infer that these alkaloids during their formation experience some remarkable change not analogous to substitution however but more allied to a splitting up of the constituent molecules and re-arrangement of these amongst themselves.This however is a matter still open for confirmation and requires further research from other experimentalists. They all contain sulphuric acid iodine and an organic base more or less modified in character. They are very soluble in boiling alcohol sp. gr. 837 and crystallize on cooling with striking physical characters by which they can be readily distinguished optically. 1st. The quinine salt is characterised by its brilliant can- IODO SULPHATES OF THE CINCHONA-ALKALOIDS. 131 tharidin-green reflected tint and strong tourmaline powers of absorption on light; the traneniitted light is polarised in one principal plane and when analyzed by any medium as a Nicol's prism or tonrmaline or by two similar plates superposed when the axes are parallel appears nearly colourless having merely a slightly pale greenish tint but when polarised perpendicularly to the axes exhibits a position of maximum polarisation and absorp- tion marked by a reddish light or body colour.The salt is characterised crystallographically by being derived from a right rhombic prism obtuse angles 115' and acute 65O having planes of truncation parallel with and perpendicular to the long axis by which prisms are produced a and p which exhibit appearances of maximum absorption when the planes of their length are at right angles to a plane polarised beam as in the a prism or parallr.with the plane polarised beam as in the case of the p prism." 2nd. The quinidine salt is known by crystallizing in long quadrilateral prisms possessing a deep garnet red colour with a purplish superficial reflcction tint and having a very slight double absorption or tourmaline power the body colour being a dark brownish red. 3rd. The cinchonidine optical salt by having equal tourmaline powers with the quinine salt; being also derived from a rhombic prism but with angles of 137' and 43O. It presents its maximum degree of absorption when the long axes of the primary rhomboid lie in a plane parallel with that of the polarised beam therefore vertically if examined by light polarised by reflection; in this case it agrees with the quinine salt.If these plates are very thin the transmitted tint or body colour is violet blue or indigo- coloured; but thicker plates wholly absorb light. The tint transmitted when the plates of polarisation are parallel is slightly coloured only pale olive-green as in quinine when very thin but yellowish green if thicker plates are examined. The reflected tint is golden or brassy yellow; and is a beam polarised in a plane parallel with that re- flected from glass; it is exhibited when a plane bisecting the long axis of the primary rhombic crystal is in a plane parallel with that of the incident light and also of reflection. The truncation planes are the same as in the quinine salt and produce a and p prisms.This salt when observed in mass in contact with fluids or glass exhibits a green tint compounded from the blue body cdour and the brassy yellow reflected rays. * Vide Proceedings of Royal Sociejy vol. vi. et sequent. K2 HERXPATII ON THE 4th. The cinchonidine of VSTittstein differs from that of Past eur in producing an iodo-sulphate having a deep yellow or siena brown transmitted light and an olive brown or dull reddish brown reflected tint. This salt is strongly doubly absorptive like quinine and cinclionidine; but its body colour is siena brown or deep bistre. The quantity did lid admit of analysis. 5th. The cinchonidine of Pasteur forms two other iodo-sul- phates one characterised as long silty golden acicuh possessed of slighter optical powers which on dissolving in boiling spirit cry-stallizes as the optical salt (No.3) ; and a dry dark olive-green re- sidue; this is derived by drying the silky salt over sulphuric acid at 62' or on exposure to 212'. This also by being re-dissolved in spirit crystallised as the optical salt whilst the optical crystals are reconverted into the silky by repose in an acid spirituous solution. 6th. The cinchoiiine salt is characterised by its long acicular form deep purplish red colour by transmission and dark purple blue reflection tint like iodine. Thin plates transmit a leinon yellow ;the transmitted light is polarised in one plane principally ; the body colour is deep siena or bistre browii according to thick- ness.* Chemically these salts are all more or less soluble in spirit giving a deep sherry-brown solution from which water precipitates them in an amorphous form as dark brown cirinamoii brown or purplish brown precipitates.They are only very slightly soluble in dilute spirit and scarcely at all in water or ether turpentine or chloroform. Acetic diluted sulphuric or hydrochloric acid has but little action upon thcm ; whilst hydrochloric or sulphuric acid concen- trated decomposes them. Nitric acid rapidly acts on them even cold-with violent evolution of nitrous acid and production of heat-iodine being liberated in a crystalline form. Alkalies decompose them also. Sulphuretted hydrogen soluble sulphides sulphurous acid and sulphites together with chlorine water instantly discolour their alcoholic solution with production of hydriodic acid.In dilute alcoholic solutions &arch gives immediate evidence of iodine. Nitrate of silver gives a yellowish white precipitate of iodide of silver and some organic basic compound which can only be * Fide Proceedings of Royal Society for fin-ther descriptionof the optical properties. IODO-SULPNATES OF THE CINCHONA-ALKALOIDS. 13.3 removed by the action of concentrated nitric acid ; this reaction is accompanied by the disengagement of nitrous acid vapours with vehemence; but it requires boiling to wholly decompose the com- pound. Baryta salts exhibit the existence of sulphuric acid which in all instances is an essential constituent in their formation.The Quinine Salt.-The analyses formerly published of this salt being defective in many respects and incomplete from the absence of any combustion or estimation of carbon hydrogen and nitrogen it has long been in contemplation by the author to re-examine this subject. Circumstances having lately greatly increased the necessity of doing so in consequence of the discovery of other salts belonging to the same class ; but one more especially iiz. the cinchonidine salt so closely similar to it that considerable proba- bility existed of the former substance having been impure.* To avoid a similar inconvenience it was first necessary to pro- duce some perfectly pure di-sulphate of quinine. For this purpose the purest commercial di-sulphate was selected by the ether test ; and the last traces of cinchonidine and quinidine were removed by first preparing the mixed alkaloids; dissolving in ether evapo- rating nearly to dryness dissolving in alcohol and slow spontaneous evaporation.As no crystals separated under either of these pro- cesses the salt mas again converted into di- sulphate and re-cry- stallized from very large quantities of distilled water. Two ounces of the di-sulphate were originally employed and as these were re-crystallized from two quantities of three pints of boiling distilled water and a third time from one and a half pint it is prcsumable that all the extraneous sulphates were entirely removed more especially as the non-crystallization from the ethereal and alco- holic solutions showed no evidence of their previous existence in any quantity.In the former process employed by the author,? a mixture of acetic acid and alcohol was employed to dissolve the di-sulphate of quinine and convert it into the neutral salt which is alone necessary for the production of these crystals. It mas thought desirable to omit the acetic acid in the present instance and employ diluted sulphuric acid which attained the same end and at the same time prevented the loss of half the quinine as acetate which occurred before and at the same time got rid of * Phil. Mag. Sept. 1852. t Phil. Nag. Sept. 1852. HERAPATH ON THE all idea of acetic acid or its elements entering into the composition of the crystals.(a).I took 60 grains of the purified di-sulphate ; dissolved it in one ounce of water acidulated with 14 drops of pure sulphuric acid 1.845 sp. gr. ; assisted its solution by heat; when fully dissolved added four ounces of water and nine ounces rectified spirit; raised the temperature to 130" Fah.; and then added 40 grains of iodine previously dissolved in four oimces of hot rectified spirit. The mixture having been well agitated was set in repose to cry- stallize. After twelve hours repose the crystals were separated on a filter and well washed with cold dilute spirit (4spt.) until they no longer presented an acid re-action; the crystals were then dried by expression between folds of bibulous paper. This mass was dissolved in 20 ounces of rectified spirit -837 by boiling and filtered rapidly; on cooling and repose the salt again sepkated.The crystals were collected on a filter washed with cold spirit dried by expression as before and again re-dissolved in 20 ounces of spirit to which a little tincture of iodine mas added in order to correct the last trace of sulphate of quinine and facili- tate the washing ; then set in repose separated on a filter washed with cold dilute and weak spirit; then with water; dried by expression and exposure to the air ; and then further dried in a hot water oven at ZOO" Fah. after being finely powdered; it was thus exposed five hours; about 64 grains mere obtained. ,6 and y. A second and third quantity were prepared by similar processes. The plan followed by the author in all the analyses was the following :-a.Iodine.-The salt was dissolved in alcohol by boiling and nitrate of silver added whilst hot ; time given for subsidence; the clear fluid decanted and passed through a filter; the residue in the beaker treated with concentrated nitric acid as before described; the resulting iodide collected on the same filter well washed dried and fused the ashes of the filter being deducted as usual. To the filtered acid solution pure cliloride of sodium was added and the resulting chloride of silver removed by filtration kc. p. To this chloride of barium was added in excess and time given for the sulphate to deposit which was collected with great care washed dried and ignited. Some of the analyses were made with nitrate of baryta which accounts for the slight excess.IODO-SULPHATES OF THE CINCHONA-ALKALOIDS. 135 y. The combustions were all most carefully made with chromate of lead and copper employed to arrest any iodine. The potass bulbs had an extra bulb &c. attached containing fused potass and the last portions of carbonic acid were swept out of the combustion tube by a current of dry and pure oxygen gas which was retained in a gasometer and passed through a t-tube filled with potassa and chloride of calcium the stream being perfectly under con-trol by carefully regulating the pressure and by a stop-cock interposed. 6. The water of crystallizstion was obtained in some instances only by the method previously used,* viz By mixing weighed portions of the dry salt with pure iron reduced in hydrogen gas and by exposing the mixture in an oil bath at 400" Fah.to a current of dry hydrogen the water being caught in a counter-poised chloride of calcium tube. E. The iiitrogen was determined by M. Yeligot's process- An acid was employed having a sp. g. of 1.01494 at 60" Fah. 510 gr. measures of which gave 24-91 grs. sulphate of baryta =-8.516 sulphuric acid dry. Now 200 measures were always carefully employed with every precaution against loss and exactly saturated by 1000 gr. measures of a standard soda-solution. The 200 measures = 3-338 sulphuric acid = 1.1683 nitrogen. The ammonia = X acid measures-these are all given in the results the formula being ZOO 1-J683 X N.Having prepared some perfectly pure optical iodo sulphate of quinine it was dried very carefully at 62O then exposed over sul- phuric acid during many days until it ceased to lose weight then submitted to Liebig's drying bath during four hours; 29.68 grs. lost *74grs. water = 2.49per cent. water Dry residue gave the following results :-I. 20.26 of the dry residue gave iodide of silver 11-32grs. sulphate of baryta 6.02 grs. 11. 6.01 grs. gave iodide of silver 3.35 grs. , sulphate of baryta 1-63. 111. 8.25 grs. burnt with chromate of lead and oxygen gas gave carbonic acid 12.57grs. , water 3.54 grs. * Phil. Mag. 1852. 136 HERAPATH ON THE IV. 11.43 p.burnt with soda-lime gave iodide of silver 6.45grs. V.14.37grs. gave iodide of silver 8.43 grs. , sulphate of baryta 4.05 grs. VI. 8.15grs. gave iodide of silver 4.78 grs. , sulphate of baryta 2.33grs. VII 6.65 grs. burnt with chromate of lead and oxygen. gave carbonic acid 10.080grs. , water 2-85grs. VIII. 10.33 grs. gave carbonic acid 15.71 gra. , water 4.225 grs. IX. 9.445 grs. gave by Peligot's process for nitrogen ammonia = 60"gr. M.acid (XOOO = 1.1683N.) = *35049N. X. 8.432grs. gave by Peligot's process ammonia = 48 acid measures (200= 1.1683 N.) = -285592nitrogen XI. 9-78grs. gave burnt with chromate of lead &c. carbonic acid 14.72grs. water 4.17 grs. Quinine-salt analyses leading to the following centesimal re-sults :-a P 7 I I1 111 IV v VI YII VI11 IX X XI Mean.Iodine . 30195 30033 -3050 31'729 31.69 --30.8295 Bul. Acid 102$6 9352 -9631 9.854 --9.7705 Carbon . -41.554 --41.34 41.456 -41.048 41-3496 Hydrogen -4766 --4'762 4.544 -4'731 47025 Nitrogen ----3-711 -3.5455 Oxygen. -----9,8024 1OO~oooO I11 VII VIIl XI Carbonic Acid . 152.3636 151.58 152.004 150.511 151.614 Water . . . . 42.911 42.867 40.90 42.638 42.326 and they produce the following ratio :-Iodine . . . . -24275= 2* atoms. Sulphuric acid . . 024426= 2.012 , Carbon . . . . 6.8582 = 56.546 , Hydrogen . . . 4.7025 = 38.74 , Nitrogen . . . . *2532 = 2.086 , *2764 = 2.27 ,, Water at 212" . IODO-SULPHATES OF THE CINCHONA-ALKALOIDS. 137 and lead to the following composition :-Theory. Expt. Means. 57 Carbon .342 = 41.606 = COz 152.55 41.3496 38 Hydrogen 38 = 4623 = HO 41.607 4,7025 2 Nitrogen. 28 = 3.409 10 Oxygen . 80 = 9.730 9,8024 2 Iodine . 254 = 30.900 30.8295 2 Sulp. acid 80 = 9,732 9.7705 822 100*000 1oo*ooo which with two 2 atoms of water additional constitutes the optical salt dried over sulphuric acid at 60” Fah. 1 dry residue as above . . 822 = 9’7.857 2 water . . 18 = 2.143 840 100.000 possibly arranged thus (C57H33N205 + 12)2S03H0 + 5H0 = 840 which appear to show that the alkaloid does not enter into its constitution as quinine; but that it receives an affix during the production of the salt of carbon and hydrogen and oxygen the amount of which can only be known upon determining the true composition of quinine. If with Laurent we assign to quinine the formula C3sH22N204 to be added toge- we require C19H’606 ther with 2 iodine and 2 sulphuric acid in order to constitute the dry residue and 2 atoms more water to produce the green optical crystals.Thus quinine ~38~22~204 t2S03H0 + 3H0 = 822 ~19~1~0 which with 2 atoms of water constitute the beautiful optical salt already described by the author C38H22N204 ) 2SO’HO + 5H0 = 840 ~‘9~11120 which would give the following results Modified alkaloid . . 52.738 Iodine . b 0 . . . 30.900 Sulphuric acid . 1 . 9.732 7 Water . . . 6.75 1oo*ooo I-IEIiAPATII ON THE These results differ some what from those previously published by the author; bnt may be easily accounted for by the discovery of an iodo-compound so remarkably similar as the iodo-sulphate of cinchonidine proves to be which contains more iodine.The purity of the substance formerly analysed is therefore very problematical -especially as in the production of that salt the author merely selected the purest commercial di-sulphate and employed it without submitting it to any preliminary puri- fication. In the former communication abundant evidence of a change in constitution was elicited by the examination of the optical proper- ties of the restored alkaloid and at that time tlie author was disposed to refer these appearances to molecular re-arrangement of the base whereby it became analogous to the ?/-quinine having lost 2 atoms of basic HO-thus becoming a monohydrate of the organic radical C20H12N02 of which a-quinine was considered the tri- h y drat e quinidine (P-quinine) the bi-h y dr ate and pi-quinine the mono-hydrate by Van Heiningen.* These speculations of the author’s must however give way to the result obtained in the foregoing analyses which have been made with great care and in a much more perfect manner than before and upon sub-stances as pure as could be obtained made at different times and yielding very concordant results.He therefore ventures to hope that the present idea of its constitution will eventually prove cor- rect in the hands of other experimentalists; he is the more con-fident in this matter as the above theoretical constitution receives additional support from his examinations of the three salts of cinchonidine which appear to be parallel and homologous salts.But in what manner these affices are obtained the author cannot presume to say in the present state of the question but ventures to suppose that during the production of the salt a splitting of an atom of alkaloid occurs the group Cl9H”O passing over to the quinine &c. to form the optical salt and the C1gH11N*03 existing in the solution in some other state of Combination water being also assimilated. This view is not discordant with the idea gaining ground i,n the chemical world that the organic alkaloids are nitrile bases in which in quinine kc. theC3*H2*04 are repre- sentatives of 3 atorus of hydrogeu. If we decide with Gerhardt however that quinine contains * Scheik Onderzoek v 319 aid Pharniac.Centralblatt lS50 p. 90 IODO-SULPHATES OF THE CINCHOh'A-ALKALOIDS. 139 C401-324N204, it follows that the affix contains C2H2lees than that previously assigned to it herein. On these assumptions we have two different formulae for the optical salt. With L au rent and with Liebig and Gerhardt Both formulze containing the same numbers of each different ele- ment and leading to the same atomic weight and centesimal results and derived from the splitting of 1 atom quinine and the assimila- tion of 7 water 5 of which are simply water of crystallisation and 2 me inherent to the sulphuric acid. The recent investigations of Strecker would appear to fix the atom of quinine as that given by Gerhardt,* &c.It is quite evident on inspection that ethyl or any of its compounds cannot enter into the constitution of this salt; we must therefore assume the derivation of the group from the split- ting of the alkaloid itself into its constituent groups and the re-arrangement of these groups amongst themselves without any substitution of hydrogen or formation of hydriodic acid. The further study of this interesting class of salts seems pregnant with important matter bearing on the real constitution of the natural alkaloids in question. SULPHATE OF IODO-QUINIDINE. Process for manufacture in quantity.-240 grs. of quinidine of Pasteurt were dissolved in 1ounce of diluted sulphuric acid con- taining 14th part oE acid 1.845 the solution being assisted by heat; the liquid was then mixed with 10 fluid ounces spt.%37 and 20 fluid ounces of distilled water the temperature raised to 130' Fah. and then 13.5 grains of iodine dissolved in 1 ounce of spt. -837 gradually added stirring well after each addition ; on cooling a mass of acicular crystals was produced; these were removed by filtration and the operation was successively repeated a dozen times; by these meaiis a large crop of crystals was at length obtained all perfectly uniform in optical characters. They were first purified by well washing with diluted spirit then with distilled water and recrystallized repeatedly from rectified spirit ; * Vide Quart. Journal of Chemical Society 1856. f-The quinidine of Leers is the cinchonidiie of Pa st eur.HERAP-4TH ON THE on the third recrystallization they were considered sufficiently pure for analysis. Water must not be employed in washing the crystals after recrystallization cold spirit only should be employed. Iftoo much iodine be used at each attempt at production an amorphous and resinoid mass is obtained mixed with the crystals from which it is difficult to purify them. The alcoholic mother-liquids from these recrystallizations furnish a further crop of similar crystals on diluting with equal quantities of boiling distilled water and setting in repose. On drying these crystals whole they decrepitate on again exposing them to atmospheric air. The solubility of the iodo-sulphate of quinidine was determined thus 65-79grs.were boiled in 2250 gr. measures of alcohol having sp. g. a837 at 62' Fah. in a retort; the condensed spirit re- turned from time to time then filtered rapidly whilst hot on a counterpoised filter which was washed with a little cold spirit dried at 212' and weighed = 4.525 grs. remained. :. 2250 gra. alcohol at 180' (omitting expansion by boiling) dissolved 61.265 :. 2250 x -837 = 30.73 61.265 Consequently 1grain of this salt requires nearly 31 parts by weight of alcohol (*837),at 180"to dissolve it. The greater portion recrystallized on cooling 1000 grs. by measure of the alcoholic solution at 62O Fah. were treated with nitrate of silver and the precipitated iodide boiled in nitric acid until all reaction ceased; the iodide washed and fused weighed 5.4 grs.A second experiment gave 4-78 grs.; mean 5.09 = iodine 2.750; which at 39.874 per cent. = 6.897 grs. salt. and 1000 x -837 --= 121 grs. to dissolve 1 gr. 6.897 The deep marone or garnet red coloured crystals had at 62' Faht. sp. gr. 1.7647. Analyses of the Sukhate of Todo-Quinidine. Salt dried at 212O Faht. during six hours:-I. 1452 grs. gave iodide of silver 10.633 = 73.23 per cent. , sulphate of baryta 2,7023= 18-611. IODO-SULPHATES OF THE CINCHONA-ALKALOIDS. 141 11. 15.82 grs. gave iodide of silver 11.63 =73.54. ,,sulphate of haryta 2.915 =18'426 111. 20.12 grs. gave iodide of silver 14.85 =73.80. IV. 11.55 grs. gave sulphate of baryta 2-12?=18.355. V. 7.32 grs. burnt with chromate of lead gave- carbonic acid- water 2-62 grs.=35,695 per cent. VI. 8-35 grs. burnt with chromate of lead and oxygen gave- carbonic acid 10.07 =120.598. water 2.975 =35.629. VII. 12-66 grs. burnt in the same manner gave- carbonic acid 15.14 =119.59. water 4-59 =36.256. WIT. 9.53 grs. burnt as before gave- carbonic acid l1.457 =120.22 grs. water 3.418 =35.865. IX. 11-32 grs. gave with iron and hydrogen in oil bath at 400' Faht.-water -803 =7.092 water per cent. X. 15.61 grs. also dried at 212' gave with iron and hydrogen in oil bath at 400'Faht.-water 1.145 =7-334water per cent. XI. 4.91 grs. burnt with soda-lime by M. Peligot's process for nitrogen (acid sp. g. 1.01493 at 60' Faht. 200' =N 1.1683) =37.4 gr. measures S03H0 =ammonia =N ,21847 =4.44 per cent.N. The above results of the analysis of the quinidine salt lead to the following centesimal computations- IIerapath Muspratt . \ \ I I1 IIJ 11 V YI V11 1111 IX I 11. 111 IV. Iodine ..3957 3974 3988 ---3973 39 831 -Sulphuric acid 639 6 326 -6306 -- - -6263 -Carbon . _--32 S9 32 615 32787 --31998 32311 Hy&ogen .--3966 3958 4025 398.5 --4001 3 937 h'itrogeii .----444 --Oxygen The author having supplied Dr. Sheridan Muspratt with a quantity of this salt has been most obligingly furnished with the results of his examination; from which it will be seen that those previously obtained by the author have been confirmed in the most satisfactory manner by that experienced analyst. RERAPATH ON THE The subjoined is an ahstract of his results :-After three hours' exposure to 218' in a hot water bath with a current of dry air it suffers no further loss at the same tempera- ture after seven hours' additional exposure to the bath.Two determinations of iodine gave- I. Iodine 39.73 II. , 39.831 Mean 39.780 Sulphuric acid 6.263 per cent. Two combustions of this salt dried at 212O for seven hours gave-111. Carbon 31.998 Hydrogen 4.001 TV. , 32.311 > 3.937 Herapath. Muspratt. Mean of 3 determinations of-Carbonic acid 120.136 11 7.8995 4 Water . 35-861 35.721 These results give the following ratio :-Carbon . -5.4606 = 34.91 Hydrogen . . 3.9245 = 25.1 Nitrogen . . *3170 = 2.027 Iodine . . -3128 = 2. Sulphuric acid . -15597 = 1.Means of Theory. Experiment. Muspratt. 35 Carbon . . 210 = 32.9670 32.764 32.154 25 Hydrogen . 25 = 3.9244 3-984 3.969 2 Nitrogen . 28 = 4.3956 4.440 -10 Oxygen . . 80 = 12.5592 12.743 -2 Iodine . 25%= 398744 39.730 39.780 1 Siilphuric acid. 40 = 6'2794 6.339 6.263 637 100*0000 1oo*ooo and would require-Carbonic acid . * . 120.879 Water . . 35-32] and probably produce the follofling formula-C35H19N204 I 2}i so3130 + 5 HO = 637 IODO-SULPHATES OF THE CINCHONA-ALIZALOIDS. 143 The formula herein given does not accord with the constitu- tion of quinidine as given by G er ha r dt . It requires the addition of C5H5to the organic base to pro-duce C40H24”204. The process for producing the Cinchonidine optical salt is the following.-The alkaloid should be dissolved in a slight excess of diluted sulphuric acid-as shewn by litmus paper; to this should be added about 16 times the bulk of rectified spirit and warmed to 100’ Faht.then tincture of iodine should be added in considerable quantity continuing the agitation after each addition. On cooling golden sparkling crystals are deposited in radiating bunches if suffered to remain in repose. These crystals have a golden greenish appearance in contact with glass and fluid and are different to a practised eye from the deep blue green of quinine salt. The cinchonidine employed must give no reaction of quinine or quinidine with chlorine and ammonia and must be wholly soluble in warm ether crystallizing on cooling in hard shining rhombic prisms.The following proportions answer admirably :-120 grains of pure alkaloid were dissolved in half a fluid ounce of diluted sulphuric acid (1 to 9) to this was added 10 fluid ounces of rectified spirit and raised to 100’ Faht.; with these were then mixed 48 grains iodine dissolved in 3&fluid ounces of warm spirit the whole having been xell agitated it was placed in repose; after 8 hours a beautiful crop of golden sparkling greenish crystals were deposited ; these were very thin and presented the beautiful blue body colour so indicative of this salt. On treating the mother-liquid after filtration with a second quantity of‘ iodine as before another crop of crystals formed on cooling. These were collected on the same filter pressed dry then expressed on bibulous paper as strongly as possible.The whole was then boiled in sufficient spirit to redissolve it and agaiii crystallized on cooling ; again filtered and now well washed with dilute spirit (1to 3) until free from acid reaction. A second and third time was this operation performed in these latter adding a little tincture of iodine to ensure eonversion of all the sulphate into the crystals and facilitate the washing which was at length completed by cold distilled water. The mass dried at 2lZo,weighed 53.7 grains but the alcoholic liquid still con- HERAPATH ON THE tained a considerable quantity in solution as nearly one pint of spirit was employed at each recrystallization in order that the salt should be obtained as pure as possible.The acid alcoholic mother-liquid on repose gave a large crop of golden-yellow silky acicular crystals in long radiating prisms very like to asbestos and of a golden colour ; these are almost opaque to transmitted light but when broad enough transmit a yellow colour ; they are very slender delicate and excessively bulky. This salt was removed by filtration mashed with dilute cold spirit until free from all acid reaction and pressed dry in bibulous paper; then again broken up in dilute spirit and well agitated filtered washed and again pressed and dried by exposure to air until it cease to lose weight. For analysis this must be spread out in thin films on a coun- terpoised capsule over sulphuric acid taking the weight from time to time then subsequently exposing it to the drying appa- ratus.It cannot be recrystallized except in an acid solution; in alcohol it forms the optical salt after redissolving. The dry olive-coloured residue also becomes the optical salt after re-solution. Several of the analyses of theoptical salt mere made from such converted specimens due care being taken to purify them as before. The substances analysed in the accompanying schedule were made at diRerent times a.nd as described obtained by various methods. Analyses of the Sukhate of lodo-Cinchonz'dine. Purified as described dried in a hot bath at 212' during 4 hours until the weight remained constant. I. 17-17 gra. gave iodide of silver 12.63 = 73.511 per cent., sulphate of baryta 4.19 = 24.461 per cent. 11. 18.34grs. gave iodide of silver , sulphate of baryta 4-63 = 25.26. 1x1. 16-35 grs. gave iodide of silver 11.92 = 73.021. , sulphate of baryta 4.23 = 25.871. IV. 14.37 grs. gave sulphate of baryta 3.7075 = 25.80. V. 11.18 grs. gave iodide of silver 8.12 = 72.62. , sulphate of baryta 2.88 = 25.352. I7I. 10,906grs, gave carbonic acid 13.97 = 128.1. IODO-SULPITATES OF THE CINCHONA-ALKALOIDS. 145 VII. 6-17 grs. gave carbonic acid 8.09 = 131.118. , water 2.40 = 38.894. VIII. 5.73 grs, gave carbonic acid 7-52 = 131.239. , water 2.22 = 38.708. IX. 8.33 grs. gave with iron and hydrogen at 430 Fah. 4 hours. water *65 = 7.803 per cent. X. 8.535 grs. gave water as before *68 = 7.967.XI. 11-36grs. gave iodide of silver 8-12 = 71.479. , sulphate of baryta 2-88 grs. = 8.593 SO3. XII. 5.30 grs. burnt with soda-lime by M. Peligot's process ammonia = 27' m. acid (200O acid sp. g. SO'HO = 1.1493 at 60" = 1.1683 N) 27" = N.15782 = 2976 per cent. These results lead to the percentage computations for the cinchonidine optical salt- A B -+-I 11. 111. IV. v. YI. VII. YIII. HI XII. Mean. Iodine . . 39727 -39.462 -39246 --38488 -39 476 Fulphuricacid 839 8673 8882 8858 8704 -_i -8.593 8 701 Cnrbon . ---34936 35.73 35-792 -35 486 Hydroden . ---4321 4'301 -4 311 Nitlogen. -----2.976 2 976 Ouygen . _-----9 058 and produce the following ratio-Iodine . 3.111 or atoms 3 Sulphuric acid . 2.175 , 2.097' Carbon .. 59.14 , 57.013 Hydrogen . . 43.112 , 41*57 Nitrogen . 2.12 , 2.045 which produce the following formula provisionally- Theory. Experiment 57 Carbon . . = 342 = 35.367 35 -486 40 Hydrogen . = 40 = 4.147 4.3112 2 Nitrogen . . = 28 = 2.884 2.976 12 Oxygen . . = 96 = 10.052 9.0388 3 Iodine . = 381 = 39.297 39-478 2 Sulphuric acid = 80 = 8.294 8-701 967 100*000 li 146 IIERAPATH ON THE and would give- Theory. Experiment. Carbonic acid . 129.68 130.152 Watcr . . 37.323 38.708 C57H33N2052S03H0+5H0 = 967 * 73} The author has rejected the determinations of the water of crystallization in this salt by means of iron and hydrogen gas as only approximative as quinoline distils at the same time and unless the temperature be well regulated the water appears very considerably increased in amount from this cause; some experi- ments have given as much as 32.22per cent.The yellow silky salt of cinchonidine may he produced without the optical salt at one operation. Thus 60 grains of cinchonidine were dissolved in half a fluid ounce of diluted acid containing 35.00 grains of dry acid; on solu-tion 5 ounces of spirit -837 were added and the whole was raised to 80’ Fah. to these were introduced 47.5 grains of iodine dis- solved in 3+ ounces of spirit. After 12 hours’ repose the beaker was filled with a dense fibrous mass of the yellow silky salt with only a few optical crystals sparingly disseminated ; after 3 days’ further repose these were wholly converted into the silky salt.They were separated by filtration and purified by washing and expression as before described; when thoroughly free from acid they were dried on a porous brick and after some days’ exposure to the air properly protected were placed over sulphuric acid in a counterpoised vessel. From the formula employed it is easily found that the acid was 1-08per cent. in the original fluid out of which nearly half the acid was necessary to combine with the cinchonidine as acid sulphate (C38H22N202 +2SO3HO). This would at first sight lead us to imagine that the salt may contain double the quantity of acid. But the analysis of the dry residue obtained by heating the salt in Liebig’s apparatus does not warrant such a conclu-sion whilst water alone is lost during this operation.Moreover the behaviour of these three substances with alcohol proves that the acid iodine and base are in the same relative propor- tions. Analyses of the dry olive-colourecl residue dried during six hours in Liebig’s apparatus. * This formula requiiec 6.432 per cent water. TODO-SULPHATES OF THE CINCHONA-ALKALOID& 147 I. 5-03gra. gave iodide of silver 3-77' grs.=74*95 per cent. , sulphate of baryta 1.345 grs.=:26*74 per cent. IT. 7-91 grs. gave iodide of silver 5.915 grs =7477 per cent. , sulphate of baryta 1-91 grs.=24- 14 per cent. XII. 4.505 grs. gave carbonic acid 5.96 grs. =132.30. , water 1-64 grs.=:36.404. IV. 4.92 grs. gave carbonic acid 6-44 grs.=130.8943. , water 1.785 grs.=36.28. V. 6557 grs. gave by Peligot's process Ammonia=32 grs. measures acid=*18696 N (200'~1.1683 N) =2*851 per cent. nitrogen. VI. 9.43 grs. gave when burnt with chromate of lead , water 3-45 grs.=36-685. CINCHONIDINE. These analyses give the following composition for the dry olive-coloured residue I. 11. 111. IV. v. VI. Mean. Iodine 40 504 40.407 -I-40,455 Sulphuric acid 9.064 8.324 --8'699 Carbon -36'082 35.689 -35.8855 Hydrogen -4.045 4'031 4.065 -4.0470 Nitrogen ---2'851 2.851 Oxygen ---8.0625 giving the following ratio Iodine .318 = 3 atoms so3 -2174 = 2.050 Carbon 5.9809 = 56.42 Hydrogen 4-0470 = 38.18 Nitrogen 20364 = 1.921 numbers which very closely correspond with the following formula Theory. Experiment.57 Carbon 342 = 36.037 35.8855 38 Hydrogen 38 = 4.004 4.0470 2 Nitrogen 28 = 2,950 2.8510 10 Oxygen 80 = 8.433 8.0625 3 Iodine 381 = 40147 4.04550 2 Sulphuric acid -80 = 8-429 8.6990 949 1m*ooo 100~0000 L2 HERAPATH ON THE and may thus be prodsionally rendered C57H33N20.5 0 13)2 ~ 0 3 +~3 HO = 949; a formula which closely corresponds with that of the optical salt but contains 2 atoms less water ;it will be shown to bear an equally simple relation to the yellow fibrous silky crystals from which this greenish black residue was obtained thus The yellow silky fibrous crystals air-dried on subsequently heating in Liebig's apparatus during six hours lost water and were converted into the olive-coloured residue.I 38.55 grs. air-dried dried at 212' lost 2.25 grs. HO =5.86 grs. per cent. This experiment was slightly in excess as the yellow salt was not quite dry. 11. 50.54 grs. more carefully air-dried at 62'' then exposed over S03H0in a powdered state during nine days ceased to lose weight gave water 2-32 grs. becoming dark olive-coloured as if it had been heated at 212O. This residue after a further exposure during six hours in Liebig's drying apparatus experienced a loss of 0.3'1 grs. therefore 2.32 +0.37 = 2.69 = 5.322 HO per cent. which will give the following composition for these crystals :-Residue previously examined 94.678 = 949 = 1atom. Water . 5.322 53.3 = 6 atoms. loooooo probably 1atom residue 949 = 94.616 6 atoms water 54 = 5.384 water 1003 100.000 From the percentages obtained by the analyses of the dry residue the following proportions will give the subjoined results :-In the silky crystals.Iodine . . 100 40.455 : 94.678 37'914 Sulphuric acid 100 8.699 : 94.678 8.216 Carbon . . 100 35.856 : 94.678 33.947 Water . . 100 36.423 : 94678 34.485 +5*322 Nitragell . 100 2.851 : 94.6'78 2.700 IODO-SULPHATES OF THE CINCHONA-ALKALOIDS. 149 We cith now compare the results derived from the formula, + 6 atoms water. Theory. Experiment. 67 Carbon . = 342 34.097 = 33.947 44 Hydrogen = 44 = 4.386 = 4.423 2 Nitrogen = 28 = 2.791 = 2.700 16 Oxygen . = 128 = 12.764 = 12.800 3 Iodine . = 381 = 37.986 = 37.914 2 Sulphuricacid = 80 = 7.976 = 8.216 1003 1oo*ooo 100~000 giving Experiment.Carbonic acid . . 125.022 124.472 Water . 39.474 39.807 and of course giving the following formula for the yellow silky fibrous crystals C57H33N2052 ~0 ~03 +9 HO =1003 We are now therefore in a position to compare the formuh for the three varieties of iodo-sulphate of cinchonidine. a. The optical salt. 6. The silky yellow fibrous variety. 'y. The dry residue derived from the latter by 1st. A temperature of 212'. 2nd. By exposure over sulphuric acid. a. Optical. C57H33N205 13}2 SO3HO+5 HO=967 p. Silky. C57H33N205 ~0 13} 2 ~03 + 9 HO =2003 y. Dry Residue. C57 H33N205 13) 2 S03H0+ 3 HO =949 ; consequently the silky crystals are the optical salt + 4 atoms of water which under the influence of' excess of sulphuric acid an$ HERAPATH ON THE prolonged delay at 62’’ are assimilated by that salt; this addi- tional water is lost on boiling in spirit and the optical salt cry- stallizes on cooling.If the temperature be not too high at Jirst the silky crptals may be produced without the appearance of the optical salt; and the silky crystals lose 6 atoms of water at 212’ and become the dry residue or tri-hydrate which when boiled in spirit -837 also assimilates 2 atoms water and becomes the optical variety. Upon reference to the results of the re-examination of the optical salt of quinine it will be seen that a very striking relation- ahip exists between these salts thus :-The formula therein given was- Quinine SaIt.C57H33N205 r} 2 S03H0+5 HO=840 Cinchonidine Salt. J Whence it appears that the only difference between them is the existence of 1 atom of iodine more in the latter salt In the case of quinine it has been shown that there mas some probability of the introduction of a group CI9H”O or CI7H9O into the organic base of the salt to constitute it thus-with Laurent or with Gerhardt But we have three different formulze for cinchonidine. 2. Gerhardt’s aud Laurent’s formed on the assumption that cinchonine and cinchonidine are isomeric and Leer s’ from direct analysis of the alkaloid and its salts thus Ger h ar dt s C40H24N202=308 Laurent’s C38H22N202=294 *Leers’ . C36H22N202=282 * Ann. Ch. Pharm. lxxxii 147-a translation of which appears in the Pharmaoecl-tIcal Journal December 1852 page 295.IODO-SULPHATES OF THE CINCHONA-ALKALOIDS. 151 taking Gerhardt's there will be an affixed group of C17H903to constitute the salt thus-c40 {,"l:K.,.,I3)-N202,2 S03+7 W0=967 according to Laurent the affix will be C19H1*03,thus-but according to Leers the group will be C2'Hl1O3,thus It will be seen that under each formula we have O2 more in the affix than in the corresponding group in the case of quinine; this of course is in consequence of the two alkaloids cinchonidine and quinine originally differing to that extent in their constitution. It is clear that to obtain these from the splitting of cinchonidine alone would be impossible as the whole formula contains O2only on either supposition; but we have already assumed and proved the assimilation of water; there are therefore 2 atoms more water assimilated in this salt which must be deductedfrom the true affix derived from the alkaloid itself; they are probably more closely basic than as water of crystallization whilst the moveable group under either formula differs from that of the quinine salt.In the present condition of the question it is impossible to decide upon the true arrangement of the atoms or even the possible constitution of the salt. One thing is apparent the striking similarity in the mode of production. The analysis of the compound with iodide of silver may throw considerable light on this subject. Process for the preparation of Subhate of lodo-Cinchonine.The alkaloid examined was proved to be free from quinine or quinidine by not showing the slightest green tint with chlorine and ammonia and to be incapable of producing any golden optical crystals when treated with iodine and sulphuric acid; the difference in its solubility in hot ether distinguished it also from cinchonidine. Two drachms were dissolved in half an ounce of diluted sul- phuric acid then diluted with 9,000 grs. water and 10,000 grs. measures spirit *837,it was then raised to 100' Faht. and 81 grs. iodine dissolved in six ounces of spirit. On repose black shining prismatic crystals presented themselves these were allowed some days to fully deposit and gradually HERAPATH ON THE develope themselves and then carefully removed without disturb- ing a black resinous mass which was also deposited on the sides and bottom of the vessel.This was easily accomplished as the latter subatance was very tenacious and hard. It was probably the same body deposited whilst the fluid mas warm as these crystals melt into a pitchy looking substance in hot spirit. These crystals having been collected on a filter and well washed the operation was repeated and the same quantity of iodine added and a second crop thus obtained. These were not re-crystallized but washed repeatedly with cold dilute spirit ; their large size rendered this an easy process especially after removing the half-dried and washed crystals to a clean filter whereas they do not re-crystallize readily Analyses of the Cinchonine-salt,-dried at 212O in Liebig's bath during six hours.I. 8.073 grs. gave iodide of silver 7.52 grs.=93*15 per cent. , sulphate of baryta. 11. 7.812 grs. gave iodide of silver 7-32grs. =93*606. , sulphate of baryta 1.19 grs. = 15.217. 111. 11-27 grs. gave iodide of silver 10*59=93*079. , sulphate of baryta 1.72 grs.= 15.261. IV. 9.27 grs. gave when burnt with chromate of lead aud oxygen carbonic acid 9.57 grs.= 103.236. water 2.95 grs. =31*71. V. 5.61grs. gave carbonic acid 5-67 grs.=101*07. , water 1.76 grs. =31*37. VI. 8.51 grs gave carbonic acid 8*54=100.352. , water 2.645 grs.=31.081. VII. 9-54grs. burnt with soda-lime by Peligot's process gave 54 measures acid (200= 1.1683 N.) = -315441N.= 3-3065per cent.The foregoing analyses of the cinchonine salt lead to the com- position :-I. IL 111. IV. v. VI. VII. Mean. I Iodine . 50.34 50.587 50.302 --50.4096 Sulphuric acid -5.247 5.217 -I -5.232 Carbon . --28'156 27-57 27.37 -27.698 I Hydrogen . -3'523 3.485 3454 -3.487 Nitrogen . ---3.306 3'306 Oxygen . ----9.8679 PODO-SULPHATBS OF THE CINCHOKA-ALKALOIDS. 153 probably producing the ratio Iodine *3968 or 3 -3 -1 Sulphuric acid . *1308 or -99 -Carbon 4*6163 or 34.9 = 35 Hydrogen . 3.487 or 26.36 = 26 -2 Nitrogen . -236 or 1.79 -Means of Theory. Experiments. 35 Carbon . .-210 = 2707410 = 27.698 26 Hydrogen .-26 = 3.4346 = 3.487 I 2 Nitrogen . .-28 = 3*7000 -3.306 9 Oxygen . .-81 = 9,5103 -9.8676 3 Iodine ..-381 = 50.3301 - 50.4096 -1 Sulphuric acid .= 40 = 5.2840 -5.232 7 -757 100~0000 C35Hl9N202 Ia) S03HO+6 HO=757 and theoretically requiring Expt. Means. Carbonic acid . 101.717 101.552 Water . 30.9114 31.383 The production of the cinchonine salt appears to depend on the abstraction of carbon and hydrogen from cinchonine and the introduction of iodine but in this case 3 atoms of iodine exist for one of sulphuric acid. Its analogy with the quinidine salt is therefore very close indeed as may be seen by comparing the two proposed formula The ruby coloured quinidine salt has been shown to consist of C55H19N204 12) SO3 t.6 HO=637 The purple red cinchonine salt is ~3511~202 Iaj S03+7 HO='157 and consist individually of the alkaloid as given by GerBartit minus C5H5,respective17 assimilating in the case of quinidiiic 2 iodine in that of cinchonine 3 iodine and in each instance tlie salt is a mono-sulphate.The bases further differ by the existence of 2 atoms of oxygen additional in the quinidine salt but in this case merely keeping up the difference originally existing betmeeii the two isomeric groups 1.54 IIANCOCK ON POISON If with Laurent we assume C3*HZ2N2O2 as the composition of cinchonine we of course oiily halie to account for the loss of C3H3from the organic base in order to constitute the new iodo- base. We have two cases therefore strikingly different from the quinine and cinchonidine salts in their method of constitution.In conclusion the author begs publicly to express his thanks to Mr. John Eliott Howard who most liberally placed at his dis-posal the necessary quantities of the purified alkaloids most of which entailed the loss of considerable time and labour in their perfect purification.

ISSN:1743-6893    

DOI:10.1039/QJ8591100130

出版商:RSC    

年代:1859

数据来源: RSC

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1.54 IIANCOCK ON POISON XII.-Some remarks on Poison obtainedfrom Arrows. BY HENRYJ. B. HANCOCK, Esq. THE accompanying specimens are of a novel form of what I believe to be the urari curare or wourali poison of Giliana men- tioned in the year 1857 by Sir R. H. Schomburgh (Pharm. J. Trans. xvi SOO) and earlier by Mr. Waterton in his ‘(Wan- derings” (3rd edit. p. 84). The idea of extracting it was first suggested to me by my friend Mr. Pepper in the summer of the year 1856;and I proceeded to extract it from some poisoned arrows brought from Guiana by Mr. Echlin who was travelling secretary to Sir R. H. Schomburgh. I deem it curious-Firstly. On account of the novel form in which it appears. Secondly. On account of the large quantities in which it was extracted from the arrows.Thirdly. On account of its preserving to a great extent (as will afterwards appear) its properties during the many years which elapsed between the arrival of the arrows in England and my experiments. My method of proceeding was very simple. I steeped the arrows in boiling chloroform and then scraped them carefully in the same liquid; after evaporating off the chloroform I obtained the poison mixed with small particles of iron from the scraping; and eventually getting rid of the iron I obtained a quantity of crystals. OB'f'AINED PROM ARROWS. On examination I found that the crystals were uearly insoluble in water but readily dissolved by chloroform and acetic acid. On testing I found slight in fact hardly perceptible traces of the presence of strychnine but could eliminate nothing further by any test I employed.I will now proceed to detail its action upon those animals which I have submitted to it. Some being administered to a frog no effect mas perceptible for the first ten minutes but after that time the aminal became lan- guid and died in about thirteen minutes from the time of adminis-tering the poison apparently without pain. After death there was none of that rigidity of the limbs which is to be observed after poisoning by strychnine nor was there anything worthy of remark in the external appearance. And this I take as a proof that the amount of strychnine in the poison is very small although there may be a slight trace as pointed out by the tests. The poison being introduced through an incision in the skin of the back of another frog the same results followed but in a shorter time the frog dying in eight minutes after the operation. Some of the poison being administered to a cat the animal walked about as usual for about twenty minutes and then became languid repeatedly stretched itself and at length lying down died quite quietly without the least appearance of pain in about half an hour from the time of administering the poison. After death there was no more rigidity than if the cat had died from natural causes.

ISSN:1743-6893    

DOI:10.1039/QJ8591100154

出版商:RSC    

年代:1859

数据来源: RSC

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OBTAINED PROM ARROWS. XI1I.-On the Composition and Analysis of Black Ash or Ball Soda. BY JOSIAHW. KYNASTON TJTUDENT IN THE LIVERPOOL COLLEGE OF CHEMISTRY. THEimmense importance and extent of the soda manufacture will it is hoped be considered a sufficient reason for the publication of the following remarks on the composition of one of the intermediate products. The process of Leblanc although so extensively and so successfullypursued is nevertheless as to several of the products of decomposition not even now after the lapse of nearly sixty years thoroughly understood. 156 KYNASTON ON THE COMPOSITION Having at the suggestion of Dr. Muspratt undertaken an investigation of the whole process so as if possible to lead to improved modes of manufacture it appeared of’ the utmost impor- tance to ascertain with accuracy the exact composition of black ash or crude carbonate of soda.Several analyses of this highly complex mixture have appeared from time to time among which may be mentioned those of Richardson Unger Brown Dan- son and more recently that of Samuelson late of this college. The most striking discrepancy in the several analyses is in the composition assigned to the insotuble calcium compound. The exact constitution of this has also been a question to which several distinguished chemists have devoted much attention and on which scarcely two have agreed. Thus Dnrnas assumes it to be a com-bination of two equivalents of sulphide of calcium with one equiva- lent of lime 2 CaS + CaO.Uiiger reviewing Dumas” theory of the process of its formation considers it much mom probable that it is a compound of three equivalents of sulphide of calcium with one equivalent of lime 3CaS + CaO a formula also assigned to it by Payen and adopted by the above mentioiied analysts; while Rose regarded it as composed of one equivalent of sulphide of calcium with one of hydrate of lime CaS + CaQ HO. illy ana- lysis appears to me to prove decisively that no such salt as any of the above has any existence in fact; and certainly that the insolu- bility of the calcareous compound cannot be attributed to its being contained in the ash in such a state of combination. Before stating the reasons for arriving at such a conclusion opposed as it is to the opinions of such eminent chemists I will give the method pursued for the determination of the several ingredients and the calculations founded thereon.The ash examined was kindly supplied to me by Mr. Edmund Knowles Muspratt and was produced under his superintendence at the Liverpool Vauxhall Alkali Worlrs. I would here express my acknowledgments to this gentleman for his kindness in explaining to me anything connected with the execution of the process of manufacture. The methods of Brown were adopted in those cases where they yield accurate results but in many instances they were proved to be quite erroneous. To estimate the relative proportions of the soluble and insoluble salts a portion of the ash was digested for some time in cold water afterwards thrown on a weighed filter and washed.The rcsults Can only be considered as approximate as by continued affusioq AND ANALYSIS OF BLACK ASIl &C. after the extraction of the salts of soda the filtrate still continues alkaline. This alkalinity is owing to the presence of caustic lime produced by the decomposition of the sulphide of calcium which by exposure to the air is gradually decomposed into sulphide and hisulphide of calcium and caustic lime 3 CaS + 0= CaS + CaS, + CaO. If the washing with exposure be still further continued the sulphur becomes oxidised giving rise to sulphite and hyposul- phite of lime and lastly to sulphate of lime all of which pass through the filter. In the estimation the washing was discontinued on the first appearance of lime in the filtrate.The residue dried at 212" gave 59 per cent. as the amount of insoluble matter and conse-quently 41 per cent. of soluble salts. To determine the respective quantities of lime and soda 1.954 grammes were taken and treated with hydrochloric acid. The filtrate was neutralized with ammonia and again filtered. From this solution the lime was thrown down by oxalate of ammonia and the oxalate of lime collected washed dried and ignited yielded 1.225 CaO CO = 35,109 per cent. CaO. This lime as subse-qnently calculated exists in the ash as follows:-22.307 = 15934 Ca as CaS 1.8564 as CaO CO 0-2344 = 0.1674 Ca as CaS 0.4245 as CaO S,O 1.0164 , CaO SO 9.2703 , CaO 351090 The filtrate from the oxalate of lime was acidulated with hydro-chloric acid and evaporated to dryness to remove silica.The chloride of sodium was converted into sulphate and the weight of the latter was 1-075 = 24.024 per cent. NaO contained in the ash as follows :-21.5705 as NaO CO 1.348 = *0994 Na as NaCl 0.1726 as NaO SO 0.6734 , NaO SiO 0.2595 ,,NaO A1,0 24.0240 KY NASTON ON THE COMPOSITION The centesimal amount of soda as carbonate silicate and alumi- nate was also estimated volurnetrically by means of a test acid. It yielded 22.5 per cent. Another larger portion of the ash 6.562 grammes was taltcn and in this quantity were determined the ultramarine silica char- coal protoxide of iron (as FeS) alumina (as NaO A1,0,) and magnesia. This was digested with successive portions of warm water until the soluble portion was completely extracted.The dark green aqueous solution was boiled until the ultramarine had deposited. This was filtered off washed dried and ignited and gave 0.9589 per cent. The filtrate from the ultramarine was acidulated with hydro- chloric acid and boiled then neutralized with ammonia. The precipitate of alumina thus obtained gave 0-4291 per cent. The filtrate from the last precipitate was again acidulated with hydro- chloric acid and evaporated to dryness and the residue treated with water left silica amounting to 0-5086per cent. The portion of ash insoluble in water mas then treated with very dilute hydrochloric acid and after expulsion of sulphide of hydro-gen thrown on a weighed filter.From the filtrate oxide of iron alumina and phosphate of lime were thrown down by ammonia. In this precipitate the iron was estimated by means of perman- ganate of potassa and yielded 0,3372per cent. of Fe,O,. After having removed lime from the filtrate by means of oxalate of ammonia the magnesia was precipitated by phosphate of soda and afforded 0.8537 per cent. of MgO. The residue undissolved by hydrochloric acid was dried at 212O and the weight noted. From this the charcoal was removed by long continued ignition and calculated from the loss of weight sustained. It gave 7-007 per cent. In another portion of ash 5.543 grammes the sand and total amount of sesquioxide of iron alumina and phosphate of lime were determined.In this case the ash mas treated with dilute hydro- chloric acid and after expelling sulphide of hydrogen the liquid was decanted. The residue was then boiled with aqua regia until only the sand remained. The latter dried ignited and weighed gave 0.901 per cent. The two acid solutions were then mixed and precipitated by ammonia. From the precipitate redissolved in hydrochloric acid the alumina was removed by excess of potassa. The preci- pitate of sesquioxide of iron and phosphate of lime thus obtained gave 2.9952 per cent. From this is subtracted the sesquioxide of AND ANALYSIS OF BLACK ASH &C. iron obtained by solution of the ash in dilute acid and which is assumed to exist as FeS; the residue 2.658 expresses the quantity of anhydrous sesquioxide of iron and phosphate of lime.The alumina was thrown down from the potassa solution by ammonia after treating with hydrochloric acid and chlorate of potassa. The percentage was 1.5609. Subtracting from this the alumina existing as NaO A1,0 which is soluble in water the residue gives 1.1318 as the proportion of anhydrous alumina. In another portion of ash 21.4 grammes sulphuric acid was estimated after treating with hydrochloric acid by precipitation as sulphate of'baryta and gave 0.2228per cent. SO,. The total amount of sulphur was determined by fusing 2.131 grammes of ash with three or four times its weight of nitrate of yotassa treating the fused mass with dilute acid and water and precipitating sulphuric acid from the filtrate by chloride of barium.The total percentage of sulphur was 14.565. The amount of sulphur existing in the insoluble state was also determined in the same manner as the preceding the soluble por-tion having been previously extracted by repeated washing. 1.546 grammes were taken and yielded 12.882 per cent. The process adopted for the estimation of sulphur as solublc bisulphide hyposulphite and sulphite was founded upon the following reactions. Carbonate of cadmium is decomposed by a solution of alkaline sulphide yielding sulphide of cadmium and carbonate of the alkali. Nitrate of silver mixed with solution of hyposulphite of soda affords hyposulphite of silver. When heated in water the latter is decomposed into sulphide of silver and sulphuric acid Ago S202= AgS + SO,.The same salt added to a soluble sulphite gives sulphite of silver; and this also on heating with water is decomposed yielding sul- phuric acid and metallic silver Ago SO = SO + Ag. In the two latter decompositions it will be observed that a quantity of sulphuric acid is produced one equivalent of which is equal to one either of sulphite or hyposulphite. The analysis was conducted as follows :-3.463 grammes of ash were exhausted with cold water. To the filtrate a quantity of freshly prepared and still moist carbonate of cadmium was added and the mixture was digested with frequent agitation till the alkaline sulphide was decomposed. The precipitate of sulphide and carbonate of cadmium was then filtered off and treated with dilute acetic acid to remove undecomposed carbonate; the residual 160 KYNASTON ON THE COMPOSITlON sulphide was oxidized by fuming nitric acid water added and the sulphuric acid produced was then estimated as sulphate of baryta ; calculated as sulphur it gave 0.267'9 per cent.To the filtrate from the cadmium salts nitrate of silver was added and the mixture maintained at a temperature approaching ebullition until the sulphite and hyposulphite were decomposed indicated hy the successive changes in the colour of the mixture. The precipitate of carbonate sulphide and metallic silver mas then filtered OR and treated with ammonia to remove the carbonate. The sulphide was then oxidized by fuming nitric acid and the sulphuric acid precipitated as sulphate of baryta; from the weight of the latter the quantity of hyposulphite was calculated; it gave 0.4852 per cent.of sulphur existing in this condition. In the filtrate from the silver precipitate the sulphuric acid was estimated as BaO SO,; and deducting that originally existing in the solution and that formed from the decomposition of hyposul-phite the residue was calculated as sulphurous acid giving 0.5808 per cent. of sulphur existing in this state. The several determinations of sulphur therefore give the fol- lowing results :-Total percentage of sulphur 14.565. Sulphur insoluble . . 12.882 including 5 as FeS , as soluble bisulphide . 0.2679 > , hyposulphite 0.4852 I> , sulphite . 0-5808 ?> , sulphate . 0.0891 14-3050 The amount of carbonic acid was arrived at by two distinct operations.3.531grammes of ash were digested with successive portions of water to remove the soluble salts. In this solution the carbonic acid was estimated by a Fresenius' and Wills' apparatus with addition of a quantity of neutral chromate of potassa to oxidize the sulphur compounds. It yielded 9.6832 per cent. The residue insoluble in water was transferred to a retort and treated with hydrochloric acid. The gas evolved was passed into a mixture of chloride of calcium and ammonia. The precipitate AND BNA1,YSIS OF HLACIC ASEX &C. of carbonate of lime thus obtained was collected washed and introduced also into a Fresenius’ and Wills’ apparatus and the carbonic acid liberated by nitric acid.It gave 8.6698 per cent. The above was found to be the only practicable method for effecting this determination. An attempt was made to estimate this acid at once in a Frescnius’ and Wills’ apparatus; but the addition of a large excess of cliromate of potassa and even of perrnanganate failed to oxidize the sulpliur compounds. Nor could the operation be effected by treating the ash at once with acid and conducting the evolved gases into a solution of chloride of calcium and ammonia as the sulphite of lime formed would introduce another error. The sulphur salts existing in the aqueous solution were readily and completely decomposed by chromate of pot assa. Another process suggested was to oxidize the sulphite of lime formed when the evolved mixture of gases was conducted into the chloride of calcium solution and to deduct the sulphite found from the original weight of the precipitate; but as it was necessary to ascertain exactly the poportion of carbonic acid in the state of carbonate of lime the process already given was adopted.Chlorine was estinaatecl by treating 2-841 gramrnes of ash with nitric acid expelling sulphide of hydrogen &c. and precipitatirig the filtrate by nitrate silver. It gave 1.533 per cent. Lastly the hygroscopic moisture was determined by heating a portion of ash to about 300O. It indicated 0.2158 per cent. From the above analysis now given in a tabular form the per- centage composition was calculated. Soluble salts .. .... .. 41 Insoluble matter and salts .* .. 53 100 Lime .. .. 35-109 Soda .. .. 24.024 U1tram ari ne .. 0.9589 Silica . *. 0.5086 Magnesia .. .. 0.2537 Charcoal .. .. 7.007 Sand .. .. 0901 Sesquioxide of iron illad7 2,9952 { including 0-3372 phosphate of lime I Fe,O existing as FeS &I KYNASTON ON THE COMPOSITION including 0.4291 Alumina .. * 1*560g( as NaO A1,0 Sulphuric acid .. 0-2228 Total amount of sulphur .. 14.565 Carbonic acid .. 18.353 {soluble 9.6832 insoluble 8.6698 L Chlorine .. . 1.533 Water .. .. 0.2158 Percentage Composition. Carbonate of soda .. .. .. 36.8786 Chloride of sodium . . .. .. 2-528 Sulphate of soda .. .. .. 0.3954 Silicate of soda .. .. .. 1.182 Aluminate of soda .... .. 0.6886 Sulphide of calcium .. .. .. 28.681 Carbonate of lime . . .. .. 3.3151 Bisulphide of calcium .. .. 0.4353 Hyposulphite of lime .. .. 1.1523 Sulphite of lime .. .. .. 2.1 78 Caustic lime .. .. .. .. 9,2703 Magnesia .. .. .. .. 0.2537 Sulphide of iron . .. .. 0.3710 Sesquioxide of iron and phosphate of lime .. .. .. .. 2-658 Alumina .. .. .. *. 1.1318 Charcoal .. .. .. .. 7.007 Sand.. .. .. .I .. 0.901 Ultramarine .. .. .. .. 0-9589 Water (hy droscopic). . .. .. 0.2158 100.201s It will be seen in the preceding analysis that the lime is calcu- lated as existing in several combinations of sulphur and as carbo-nate and caustic lime. The reasons for this will be apparent from a study of the analysis. Thus it will be observed that in the determination of the carbonic acid 8-66 per cent.was found to exist in the compound after treatment with water as carbonate of lime while 22.307 per cent. = 15.93B of calcium is shown to AND ANALYSIS OF BLACK ASH &C. exist as sulphide of calcium CaS the proportion of sulphur remaining insoluble after deducting that combined with iron as FeS being the quantity required to produced CaS. Therefore it is evident that in the portion of the ash insoluble in water-that is to say in soda waste no lime exists either combined with CaS or in the free state. It must however be acknowledged that this analysis does not disprove the presence of some such compound in the ash as removed from the furnace and before treatment with water.But why assume the existence of such a compound and what end is to be served? Dumas when showing the necessity of adding a quantity of lime above that required to produce CaS says:-“But it must yet be observed that if only two atoms of chalk be used on dissolving in water the sulphate of lime converted into sulphide of calcium by the charcoal will be decomposed by the carbonate of soda and the result will be the reproduction of the the chalk together with sulphide of sodium. On this account three atoms of chalk are used because then one atom of lime remains free and uniting with the two atoms of sulphide of cal-cium produces a compound insoluble in cold water. Thus only the carbonate of soda dissolves and entirely escapes decomposition by the sulphide produced.” From the above extract it is evident that Dumas assumes the existence of his 2CaS + CaO because the additional atom of lime has the effect of rendering the CaS insoluble; and this fact is generally adopted by others as a proof of the existence of this or a similar compound and certainly the conclusion seems a very plausible one.But if by treatment with water in contact with the alkaline carhonate it is found that the lime supposed to be combined with sulphide of calcium is removed from it and coil- verted into carbonate with simultaneous production of the objectionable compound then what becomes of the theory when the very fact that led to its adoption is shown to be erroneous? Unger besides the above reasons from analogy and con-siders that because Rose on leaving a baryta solutionfor some years in a bottle obtained a compound having the formula 3 Bas + BaO + 28 HO that therefore the compound 3 CaS +CaO might reasonably be supposed to exist.But what analogy is there between the two compounds? Were the above baryta com- pound known in the anhydrous condition 3 Bas -+ BaO then we might reasonably assume the existence of the corresponding salt 3r 2 KYNASTON ON ‘rm CONPOSITTON 3 CaS + CaO. But this is unknown and therefore the analogy falls to the ground. But it will be asked horn then does the additional atom of lime render the CaS so insoluble? I must confess I am not quite prepared with an answer to this question; but would say iu reply is it not as rational to suppose that an atom of carbonate of lime may unite with the CaS to produce a difficultly soluble compound 2 CaS -j-CaO CO,? If we adopt this opinion and suppose that combination immediately ensues on treating the ash with water all difficulty is at once removed.In the examination of another sample of ash the annexed results were obtained :-Carbonic acid as carbonate of lime 8,993 per cent. Total quantity of lime . . . . 35,348 , Sulphiu in the insoliible state 12.768 , These determinations give the followiiig results :-Lime = 15.96 calcium as sulphide 22*344= 28.728 CaS , as carbonate of lime. . . . 11.445 = 20.438 CaO CO 1. , , caustic . . . . 1.659 The above although a small quantity of lime remains free is another proof of the non-existence of any of the hitherfo assumed conzpounds but is not inconsistent with the theory broached above the quantity of CaS there given requiring 19-95 CaO CO to form 2CaS + CaO CO,.Another explanation of the fact why the additional quantity of lime sliould prevent the solution of the sulphide is by sup-posiiig that the excess of lime prevents the formation of bisulphide as in my opinion only the bisulphide and not protosulphide of calcium is decomposed by the solution of alkaline carbonate. If the supposed compounds of Dumas and Unger are more stable than sulphide of calcium why are they so readily decomposed by exposure to the air as is shown in the decomposition proved to take place in the extraction of the soluble salts and how is it that the products of this metamorphosis are precisely those which occur in CaS under similar circumstances ? By Unger and others a large quantity of hydrate of soda has been found; I believe no caustic soda can possibly be produced and certainly from Unger’s own results none is proved to exist although he has calculated it in this condition.It has been AND ANALYSIS OF BLACK ASH &C. suggested that NaO may be produced by the expulsion of carbonic acid from the carbonate of lime and a subsequent decomposition of the CaO and sulphide of sodium; CaO + NaS = CaS + NaO. But according to the theory of Dumas the sulphate of soda first decomposes with carbonate of lime forming carbonate of the alkali and sulphate of lime and this salt is afterwards reduced to sulpliiile of calcium by the charcoal.111 this case no sulphide of sodium can have been formed and as carbonic acid once corn- bined with soda cannot be again removed by simple heating of course no caustic soda can beproduced. Whether a sulphite and hyposulphite actually exist is a ques- tion that hardly adinits of proof though my researches would certainly lead to the conclusion that they do; for on treating with cold water the first washings were found to contain sulphide sulphite and hyposulphite though I allow the possibility and even probability of the formation of these subsequent to the removal of the black ash from the furnace. In the experiment last given another curious fact was observed yiz.the existence simnltaneously of sulphurous acid and sulphide of hydrogen. Sulphurous acid was distinctly perceptible by its pungent and peculiar dour on adding hydrochloric acid while lead-paper was blackened by the gas eliminated. Of course the two gases col-lected would mutually decompose in the subjoined manner :-IA 2HS + SO 2HO + 3s +’ L-7--’ + + Sulphide of hydrogen. Sulphurous acid. Water. Sulphur. Many eminent chemists have asserted that the two gases could not be collate~ally evolved ; but this as Dr .Muspr att affirms is placed beyond a doubt by his own experiments and by mine NOTE.-The sample of ball-soda operated upon by the author had probably beerr exposed for a considerable time to the s1r ; since it is well known that the lixivium obtained in the ordinary mode of tre king ba!l-sods always c ntsins a cocsiderable proportion of caus ic alkali the presence of which woiild probably interfere with the application of the author’s new methods of analysis to the determination of the sul- phidefi hyposulphites &c.in such lixivium.-[Er~]

ISSN:1743-6893    

DOI:10.1039/QJ8591100155

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

XIV.-Process foy the quantitative estimation of Sickhides Sul-phites Hyposulphites and Sulphales inpcsence of each other as adopted in the determination of these salts in ‘; Soda Waste,” as obtainedfrorn ‘‘ Black Ash.” BYJ. TIT.KYNASTON BTUDLNT IN I’Hh LlVERPOOL COLLEGE OF CHEMISTRY. THTSmethod is founded upon the decomposition of an alkaline sulphide by carbonate of cadmium ; CdO CO + NaS = CdS+ NaO CO, and on the changes produced in hyposulphite of silver and sulphite of silver when heated in water nearly to boiling which way be expressed thus:-Ago S,O = AgS + SO, and Ago SO = Ag + SO,. By means of the above reactions these sulphur salts may be estimated without difficulty and with positive certainty as is proved by the siibjoined experiments. To overcome the difficulty of obtaining a sulphide containing a definite proportion of sulphur 100 measures of a very dilute solu-tion of sulphide of ammonium were taken.In 50 measures the proportion of sulphur was estimated by precipitating as sulphide of copper. The sulphide was oxidized by nitric acid and the sul-phuric acid precipitated as sulphate of baryta and yielded 3.7364 grammes BaO SO = 1.0904of protosulphide of ammonium NH S. The other half of the solution of course containing the same amount of sulphide was reserved for estimation in admixture with the other salts. A similar difficulty arises in obtaining n sulphite of definite composition and this was overcome in a similar manner. A neutral solution of sulphite of soda was prepared and 100 rneasizres taken in half of which the sulphite was estimated- after oxidizing by means of chromate of potassa and acidifying- by precipitating sulphuric acid with chloride of barium.The weight of BaO SO obtained was 0.6502 grammes = 0.3516 of sul-phite of soda NaO SO,. The other 50 measures representing the same weight of sulphite were added to the solution of sulphide of ammonium. Afterwards 1.146grammes of crystallized hyposulphite of soda pulverized and pressed in bibulous paper were dissolved andadded to the mixture and lastly 1,213 grammes of anhydrous sulphate of soda. Thus was produced a solution containing 1.0904 KYNASTON ON SULPHIDES SULPHITEP &C. grammes NH,S ;0.3516 of NaO SO 1.146 of NaO S,O,; and 1.213grarnmes of NaO SO ;which would afford a mixture having the following percentage composition :- Sulphide of ammonium .. 28.687 Sulphite of soda . . 9.250 Hyposulphite of soda . . 30.150 Sulphate of soda . 31.913 100~000 To this mixed solution a quantityof carbonate of cadmium was added and the whole was digested for some time with frequent agitation. The mixture of sulphide and undecomposed carbonate of cadmium was then filtered off and treated with acetic acid to remove the latter salt. The residue of CdS was then treated with nitric acid. Only a portion of the sulphur was oxidized the residue was collected by filtration dried and weighed giving 0.3205 grm. of sulphur. From the nitric acid solution the sulphuric acid was thrown down as sulphate of bargta and the weight of thelatter was 1.3782 grammes.This and the separated sulphur represent 1.0833 of NH,S = 28.5004 per cent. To the filtrate from the cadmium salts nitrate of silver was added as long as a precipitate was produced. The mixture wits heated nearly to ebullition arid kept for some time at that tempe- rature. The silver precipitate was then collected washed and partially dried then treated with concentrated nitric acid. The whole of the sulphide was oxidized and the sulphuric acid formed was precipitated as eulphate of baryta giving 1.0732 grammes = 1.1423 NaO S,O + 5 HO = 30.0526 per cent. The sulphuric acid in the filtrate from the silver precipitate was thrown down as sulphate of brtryta and yielded 3.7276 grammes. Subtracting from this 1.9889=the quantity of NaO SO present and 1.0732 = the NaO S,O, 5 HO found above the residue represents the quantity of NaO SO,.Total weight of BaO SO . . 3.7276 BaO SO = 1.213 NaO SO . 1.9889 1.7387 , = 1.1423 NaO S,O + 5 HO . 1.0732 = BaO SO NaO SO remaining . . 0.6655 NAPIER OX METALLIC DEPOSITS &C. This residue 0.6655 BaO SO represents 0.3598 of NaO SO,= 9.4659 per cent There are found therefore :-Sulphide of ammonium . . 28*5004 Sulphite of soda . . 9-4659 Hyposdphite of soda . . 30.0526 Sulphate of soda . . 31,9130 99,9319 T now append the iiumhers collaterally to prove at a glance the accuracy of the methods employed :-Theory. Analysk. Sulphide of ammonium . . 28.687 2Bb5O0S Sulphite of soda Hyposulphite of soda . . . 9-250 30.150 94659 30,0526 Sulphate of sQda . 31.913 31.9130 -_I- c__L- 100-000 99.9319 This process answers equally well in presence of a large pro-portion of alkaline carbonate; but in this case it is necessary to treat the silver precipitate with liquid ammonia to remove car-bonate of silver previous to the oxidation of the sulphide.

ISSN:1743-6893    

DOI:10.1039/QJ8591100166

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

NAPIER OX METALLIC DEPOSITS &C. XV.-Bernarks on Metallic Deposits found in two Chimneys attached to Reverberatory Furnaces one being uaed for Melting an Alloy of Silver and Copper and the other an Alloy of Silver and Gold. BY JAhiEs NAPIER, ESQ,SUN. CHEMIST AND ASSAYER TO THE GUAN~XIJATOMINT MEXICO AND LATE IN THH LABORATORY OF ST. THOMAS’S HOSPITAL LONDON.* IN a paper which Dr. Thomson was kind enough to communicate for me to the society in June of last year,? I endeavoured to point out from our every day experience and from experiments that gold (even in its pure state) when fused and exposed in that con-dition to the ordinary temperature of our melting furnaces is like most other metals volatile; but Mr. C. J. Devey of Birmingham in the Mining Journal of the 31st March 1855 goes as far as to * Communicated by Robert Dundas Thomson M.D.F.R.S. .t. Chrm. SOC.Joimi. x 229. 169 NAPIER ON METALLIC DEPOSITS &C. state that gold does not require even to be melted to volatilize but to be heated only to a good red heat. This experiment I have tried repeatedly keeping thin slips of pure gold (about 2 inches in length and + an inch in breadth) at a good red heat for 10 hours at a time but never found the slightest diminution of might although the gold operated upon became very soft and as ductile as a piece of lead and the surface was covered with small blisters (if we may use the term). It is probable that the gold used by Mr. Devey for his experiments was contaminated with some other metal which carried off the gold.I hope by the following facts to be able to point out clearly the great danger of melting tbe precious metals in open furnaces without some contrivance for the condensation of the whole of the soot &c. which passcs up the chimney and also to show that volatilization is one of the great causes of loss in melting these metals on the large scale. The following table shows the analyses of deposits taken from the top middle and bottom of a chimney about 35 feet high attached to a small reverberatory furnace in which is melted almost daily for months together an alloy of silver and copper (silver coin) with z sinall portion of gold so small as not to pay for its extraction in this country (Mexico); the ayerage proportion of this metal will not exceed 3 grains per mark (8 ounces) of alloy and in no instance does the alloy contain as much as 8 grains of gold per mark.During the whole of the time from 2 to 3 hours the alloy is in the melted state its surface is thickly covered with charcoal. Substances found. Bottom. Middle. Top. Mean. -_-Metallic silver .. .. .. ,. 29.950 9.190 3.300 14.170 Oxide of silver .. .. .. .. -170 5210 '7'180 3 186 Metallic copper .. .. .. +. 2.800 -250 '1 20 1-066 Oxide of copper .. . . .. .. 1.930 940 *150 '940 Oxide of iron and alumina .. .. 7.300 '11.430 10.390 9.706 Cub. lime and magnesia.. .. .. 43.850 40.720 52.690 48.420 Silica . .. .. . . . 14.000 23.510 24.220 20.576 Carbonaceous matter . .. .. .. .. -960 1'260 -"140 100*000 100'010 99.310 98.804 Total metallic silver .... ,. 30.056 12,461 7.808 16.775 Total metallic copper .. .. .. 4.344 -842 '240 1.808 Grs. of Gold per mark of silver .. . . 8 A quantity of soot was also collected as it escaped about 4 feet NAPIER ON METALLIC DZPOSITS &C. from the top of the chimney and on examination it was found to contain 3 per cent. of silver with also a small portion of gold. Soot deposited on a wall against which the chimney stands was found to contain 4.2per cent. of silver which silver contained also gold. Such results require no comment to show the large loss of silver sustained in melting this metal in open reverberatory furnaces. On referring to the above table of analyses it will be seen that as we ascend the chimney the oxide of silver increases in amount and this from the character of the metal and taking all circum- stances to which it is exposed into consideration is what we might expect.I think there is little doubt that the silver is volatilized in the metallic state for the deposit from the three parts of the chim- ney when examined through a lense is found to be perfectly full of very small particles of silver-almost an impalpable powder ; but when this deposit remains for a time in contact with the air and is exposed only (while the furnace is working) to a gentle heat the silver is partly converted into oxide; the top of the chimney being most exposed to the action of the atmosphere and a gentler heat it is there we might expect and do find the most oxide of silver.At the bottom on the contrary we find only a small portion of oxide and this I conceive is because this part of the chimney is when the furnace is working always at a strong red heat and oxide of silver I think will neither form nor exist under the influence of a strong red heat; the sinall portion of oxide of silver found at the bottom is probably formed after the fire is extin- guished and the deposit cooled in a current of hot air. From the above analyses and frcm observation I am led to suppose that most of the copper also passes off in the metallic state combined with the silver as alloy-that is to say although copper of itself is not volatile in the metallic state it can when combined with another metal which is so such as silver be carried off in that form and like silver is partially converted into oxide after deposition; in fact there is no other way by which I can account for the presence of metallic copper as there is no circum- stance under which the deposit is placed in the chimney by which oxide of copper (had it passed off in that form) could have been converted into the metallic state the circumstances tending to the opposite result.The presence of the metallic copper is also a stronger proof of NAPIER ON nmrAu,LIc DEPOSITS &c. the silvcr having been carried away as metal and not as a cele- brated chemist has lately supposed in the form of an oxide which according to his theory would be reduced after deposition.If we suppose that the silver actually volatilized as oxide and afterwards became reduced in the chimney it would be impossible that such silver could contain copper in the metallic form for it is well known that this latter metal when alone in fusion will pass off in no other state than that of an oxide. Moreover the two metals would not be found as an alloy as they are but separate; from these facts I think it natural to suppose that both metals have been carried away in the metallic form but I have no doubt that a small portion of the copper does pass off as oxide. At the bottom of the chimney the deposit naturally contains the largest percentage of oxide of copper for the greater the heat to which this metal is exposed the greater tendency has it to oxidize.The next and perhaps the most extraordinary feature in these analyses is the presence of gold in such large quantities the amount being at least double that which originally existed in the alloy. The presence of gold in this depositwas not so much calculated to excite surprise after having proved that this metal when pure was to a certain extent volatile when kept in fusion; but I was much puzzled and at a loss to account for the pre-sence of a larger quantity than originally existed in the melted alloy. It occurred to me from results stated in my paper of last year,* that the copper was the agent which carried the gold away in such undue proportions as the affinity of these two metals for each other is very great.To endeavour to explain this however I made the following experiments. In the first place I obtained a piece of silver con- taining by assay 1116 grains of gold per mark-no other metal- and kept it in a fused state for five hours its surface being covered with charcoal; at the end of this time it was removed from the fire and again assayed for gold when it was found to have increased to 1141 grains per mark showing that the volatilized portion (for it lost in weight) did not contain so much gold as the original alloy. Secondly. I prepared a piece of alloy having- 1000 grains of gold per mark of alloy 11 per cent. of copper and the remainder silver. * Chemie. SOL Journ. x 231. 172 NAYIER ON METALLIC DEPOSITS kC. This was fused and kept so with its surface covered with charcoal for 3$ hours after which it gave of gold only a trifle under 1000 grains per mark.These experiments were repeated various times with alloys containing from 4 grains to 1000 grains of gold per mark and the same result was always obtained. Although these experiments do not clearly prove why the silver in the refuse should have more gold than the alloy melted in the furnace I am still of opinion that the copper is the cause and there may be circumstances unknown to us to which the alloy is exposed in the furnace which do not operate on the small scale. However in all cases where copper was present in the above experiments the alloy after fusion alwtays contained a little less gold than before fusion.I may here refer to a few facts observed in conducting these experiments which may not he void of interest. The above alloys when in fusion mere always as stated kept covered with charcoal; if this be avoided and the same operation gone through the result obtained is very different. For example an alloy containiIig- 842 grains of gold to the mark of alloy 20 per cent. of copper and the remainder silver mas kept in fusion for an hour and a half without charcoal or other carbonaceous matter when it was again assayed and gave 355 grains of gold per mark showing an augmentation in gold to the extent of 13 grains per mark. There was formed on the surface of the alloy during fusion a crust of oxide of copper which when examined contained a third of its meight of metallic silver-not a trace of oxide-and what is most singular onlg the smallest trace of gold; and the silver under the claust of oxide contained only a trace of copper.Here we have a proof of the little tendency which gold has to combine with oxide of copper although it is most difficult to free gold from metallic copper l~yfire. A short time since an extraordinary instance of the affinity of gold for copper occurred in a metallurgical work in this country. An ore containing sulphide of silver and copper Ivith also gold was treated by the barrel process of amalgama- tion,to obtain the gold and silver. Jn the calcinatioii of the ore \tiit-common salt some of the capper W~S convcrtcd into sulphate which when introduced into the barrels with irou was rednced to the lnetallic state and CornbinCd Wit11 t1lC nlercllry ad tht~ewas formed amalgam of coppw and silver This amalgaiii mas freed NAPIER ON METALLIC DEPOSITS &C.from mercury in the usual my by burning under a copper bel1,- but mark the result; when the burning was concluded the bell removed and the mass examiued it was observed that it had separated into two parts in burning. The outer surface or crust was white and had the form of a cauliflower and contained-Silver . . . . 74.15 Copper . . . . 25.32 Gold .. .. -33 100~00 whilst the interior part mas brown and gave by analysis-Silver .. .. 4.00 Copper .. .. 61.97 Gold .. 34.03 10@00 The next table shows the analyses of deposits taken from a chimney about 35 feet high atta.ched to a small reverbatory furnace used for melting an alloy of silver and gold for granula-tion previous to its being dissolved in sulphuric acid to obtain the gold.The melted metal is not as in the previous case covered with charcoal but there is kept floating about on its surface a number of bone-ash cupels for the purpose of absorbing small quantities of lead which at times exist in some of the silver operated upon. The deposits taken from the bottom middle and top of the chimney gave by analysis the following results :-Substances found. Metallic silver ...... .. Oxide of silver ........ Metallic copper .... .... Oxide of copper ........ Gold .......... Oxide of lead .... .... Oxide ofantimony ......Carbonaceous matter ...... Insoluble in acid ...... .. Lime magnesia iron and aluminum .. Total metallic silver .. .... Bottom. 48 950 *032 .... *750 4.250 slight trace .... trace 25 300 Middle. Top. Mean. 39.160 29.380 39 -096 3 140 1.982 1 *718 *250 *250 -166 -125 -125 333 2 640 2 +120 3 003 2 .zoo 2 .BOO 1,666 +091 -111 ,067 3 '390 4 200 2 530 26 *500 33 900 28 566 19 918 22 -304 24.332 22 *188 99 000 99'800 99 200 99 333 48 779 42 -083 31 *225 40 695 HADOW ON THE ACTION OF Here again we have an undeniable proof of the great loss sustained by the volatilization of the precious metals ; and when we remember that it is only that portion of the metallic substance which touches the sides of the chimney that lias any chance of' being recovered by deposition we can at once sec the great neces- sity there is on the part of those engaged in the reduction or melting of the precious metals on the large scale either to employ some means for the prevention of such loss or to devise some kind of condensing chambers to retain the volatilized metal.Guanhxuato Mint (Mexico) March f?6th,1858.

ISSN:1743-6893    

DOI:10.1039/QJ8591100168

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

HADOW ON THE ACTION OF XVL-Notes on the Action of Oxidising Agents on Xul;phocyan,idcs. BY E. A. HADOW, ESQ. DEMONSTRATOR OF CHEMISTRY IN KING’S COLLEGE. HAVING had occasion to estimate approximately the amount of sulphocyanide contained in a certain solution thc plan adopted as being most speedy was that of estimating it by its power of deco-lorising when acidulated a solution of permanganate of potash previously graduated by pure sulphocyanide of potassium. In doing so I was struck with the large amount of permanganate decolorised by a given weight of sulphocyanide compared with that required by a similar weight of metallic iron for the gradua- tion of the ores of which the solution had originally been prepared; and I was inclined to imagine at first that an entire oxidation of all the elements must have been brought about; but on actually estimating the amount of oxygen imparted by the permanganate it was found to be only between 5 and 6 atoms of oxygen for every atom of sulphocyanogen a quantity sufficient for the oxidation of the sulphur alone without any surplus for attacking the hydro- cyanic acid with which it was then not difficult to perceive that the solution abounded.It appears sui*prising that a body like hydro- cyanic acid related as it is to formic acid should resist a power- ful oxiding agent like permanganate of potash better than the sulphur with which it was in combination; but such is the case; and not only so even a strong solution of permanganate has no apparent action on hydrocpnnic acid of Sc hcele’s strength pro- OXIDISING AGENTS ON SULPHOCYANIDES.vided the mixture is acidulated by some stronger acid; if on the other hand the mixture is neutral or alkaline instant decom- position and decoloration ensues. The ease also with which the sulphur of sulphocyanides is oxidised is not less remarkable it being by no means necessary to use such a powerful agent as per- manganate of potash. Black oxide of manganese rapidly attacks the sulphur of even a very dilute solution of a sulphocyanide when acidulated and so it might be concluded would bichromate of potash afact which I had incidentally observed on a former occa- sion while estimating the carbonic acid in a sample of gas lime when in order to prevent the escape of sulphurous acid (from the hyposulphites which were present,) together m ith the carbonic acid some bichromate of potash was added to the mixture; it was then noticed while sucking out the carbonic acid after the opera- tion was over that there was a strong flavour of hydrocyanic acid in the gas drawn out.Peroxide of lead like the other reagents has no effect on neutral sulphocyanides; any acid however even acetic instantly renders it active and it immediately turns white from formation of sulphate of lead. It is necessary at the same time to remark that simple as the ultimate action of oxidising agents appears to be it evidently passes through various complex stages which are perceptible enough when permanganate of potash is used the first portion is rapidly and perfectly decolorised but after a certain point the red of the permanganate instead of in- stantly disappearing passes through shades of yellow and brown before finally becoming colourless and lastly peroxide of manga- nese is precipitated.This is not due to gradual diminution of sulphocyanide for then dilution oilght to produce the same result which it does not but to the successive oxidation of distinct products and if the solutions be used conceiitrated a yellow body (probably pseudosulphocyanogen) is precipitated. This does not however explain the decomposition ;for as sulphuric acid makes its appearance from the very first while there is but little hydro- cganic liberated until quite towards the last-there must be some cyanogen compound formed containing less sulphur than sulpho- cyanogen and yet capable of reddening persalts of iron like a sulphocyanide for even when the stage of slow decomposition of permanganate commences the addition of perchloride of iron pro- duces intense reddening; and if we may make a supposition from the amount of oxygen contained in the permanganate which has been used up to this point namely 3 atoms of oxygen for 1 at.of snl- phocj-anide which would suffice to oxidise half the sulphur tlic body remaining shculd have the composition HSCy. Gap Lussac did indeed in 1815 prppare it body by the direct combination of cyanogen and sulphurctted hydrogen to IT hirh Laurcnt assigns the above composition though othcrs have declared it to be a ses~zci-hydrosulphate of cyanogen.Should Laurent's formula be correct it appears by no means unlikely that it may be the inter- mediate body which is n anted to explain the fact-of there being at least two stages in the decomposition of sulphocpas,ides by perman- ganate of potash; it is however described as so unstable and the properties assigned to its solution are so little characteristic that no attempt has been made to prove their identity. This method of liberating hydrocyanic acid from sulphocya- nides namely by oxidation in the moist way may perhaps be pro-fitably applied by some gas companies to the production of ferrocyanides from the hitherto useless sulphocyanides contained so abundantly in the waste materials after their employment for gas purification.In the case of gas-lime the quantity of hypo-sulphites likewise present would most probably prevent its pro- fitable application but this is not the case with waste hydrated oxide of iron; here no hyposulphites are present to interfere and the sulphocyanide (chiefly of ammonium,) is likewise coii- tained in a much more concentrated form arid is extracted by water without the least difficulty so that its employment for such a purpose is in every way the best. The two requisites are of course a cheap source of oxygen and a ready mode of separating the hydro- cyanic acid for conversion into ferrocyanide. Peroxide of mau- ganese with snlphuric acid at first suggested itself as a cheap oxidizing material likely to answer and various experiments were made to determine how nearly the product obtained corresponded with what theory required.Distillation was the method employed for the separation of the hpdrocyanic acid which it effects very rapidly and easily. It was found howercr that only about 2 of the whole amount of hydrocyauic acid was actually obtained and if the mixture was too concentrated or too much sulphuric acid had been used considerably greater loss of hydrocyanic acid was sus- tained due to its partial conversion into formic acid and ammonia. Nitric acid was then tried and found to be a much more satis-factory means of oxidation; the decomposition is much more complete simple and rapid; the nitric acid is little if at all destructive to hydrocyanic acid so that from 80 to 90 per cent.of the theoretical amount is readily obtained; and on one occasion when especial care had been taken in the condensation the entirc theoretical amauut of hydrocyanic acid was collected. Again nitric acid being fluid it mixes with the sulphocyanide and thus presents no obstacle to distillation in a still such. as Coffee's contrived to admit of the continuous distillation of a flowing stream exposing a large surface for evaporation which would be a more difficult matter if any insoluble oxidizing agent were employed The hydrocyanic acid thus obtained is readily condensed by allowing the products of distillatiolnto pass into an alkali or a milk of some alkaline earth- and the cyanide produced is afterwards readily convertible into ferrocyanide by adding to the alkaline solution a proto-salt of iron as long as the protoxide at first precipitated is redissolved by stirring or the green colour of the mixed oxides changes to red Milk of lime might be used to absorb the hydrocyanic acid which could then be converted into ferrocyanide of calcium by proto- chloride of iron and separated by crystallisation from the other salts present ; and the calcium salt might afterwards be converted into the corresponding potassium salt by carbonate of potash.Were the nitric acid in its action on sulphocyanides readily to part with 3 atoms of oxygen becoming reduced to NO, nothing could be more satisfactory ; for the deutoxide separated from the hydro. cyanic acid by means of the base might afterwards be brought in contact with the oxygen of the air and thus be again rendered fit for employment for the same purpose ; unfortunately how- ever the deoxidation of the nitric acid does not for the most part proceed further than the reduction of it to NO, which is consequently taken up by the lime or other base together with the hydrocganic acid; this does not however prevent the con-version of the cyanide of calcium &c.into ferrwyanide provided the base employed be in excess. The nitrite of lime in the mother liquid after the crystallising out of the ferrocyanide though not readily available for oxidising a fresh quantity of sulphocyanide might yet be advantageously employed in the manufacture of sul-phuric acid from the sulphur likewise so abundantly contained in gas refuse for the weakest acid eufices to evolve the nitrous acid even in the cold.11. The aetion of nitric acid on sulphocyanides is attended with a reaction which scarcely seems to have been noticed in any chemical work namely that just as the action commences an intense reddening of the liquid occurs most closely resembling in H colour a solution of sulphocyanide of iron. When first observed I did not feel satisfied that because no iron could be detected in the mixture by ordinary tests there was none really present for on the one hand sulphocyanide of potassium might exceed all other tests in delicacy or an the other some cyanogen compound of iron might be present in which the properties of the metal were disguised until liberated by the action of nitric acid; that such however ’was not the case was ascertained by boiling the red liquid until it had become colourless from the destruction of the sulphocyanides and when cool adding more of the sulpho- cyanide.Had the tint been due to iron the red colour would then have been restored as it was however it remained colourless. Pure colourleas nitric acid produces no colour when added to a sul-phocyanide in the cold; if however the temperature be slightly raised coloration takes place immediately attended with simul- taneous formation of sulphuric acid; for if a little chloride of barium be previously added a cloud of sulphate of baryta will be wen to make its appearance together with the first shade of red.If however red nitrous vapours be passed into a sulphocyanide the same intense colour is produced but without the immediate formation of sulphuric acid although this soon takes place ;and if chloride of barium be added it may be observed that when the cloud of sulphate baryta begins to appear the liquid at the same time begins to lose colour. Pure nitrous acid as evolved from R nitrite on trcating it with acetic acid has no power of coloking a sulphocyanide; for when a solutiou of the latter is added to a mixture of the two former no change is observed even though the atmosphere above the liquid is coloured. The acetic acid in no way prevents the coloration by nitrous vapours whether evolved from nitric acid acting on starch or obtained by the oxidation of binoxide of nitrogen; hence it appears that peroxide of nitrogen is really the agent which produces the coloration of a sulpho-cyanide.Having ascertained that a sulphocyanide was coloured by peroxide of nitrogen but not by nitrous acid I hoped by its means to ascertain whether the so-called hyponitrate of lead obtained by hoiling the nitrate with metallic lead were really a direct compound of oxide of lead and peroxide of nitrogen or not rather a mixture of basic nitrite arid nitrate of lead concluding that if NO (an acid,) were displaceable by acetic acid NO, being as its name would lead us to infer an oxide and even stated to have no acid properties irronld at lcnst be equally readily liheraterl by acetic acid; on making the experiment with various basic nitrites and hyponitrites of lead no trace of NO could bc detected.These experiments however in reality entirely fail to settle the point; for NO, though termed an oxide behaves in all cases like a combination of NO and NO, so that if the gases which powerfully redden sulphocyanide he first passed into ail alkaline solution and the product be then treated with acetic acid and a sulp hocynnide no reddening occurs although vapours of NO appear abnndantly showing that the base has split the NO into NO and XO,; the same is the case wlien NO is passed into an alkaline acetate; here however KO only is absorbed and NO remains free and thiw we hare a method of freeing KO from NO,. The point home~er,to be noticed is that acetate of lead acts in the same way decomposing KO4 into NO, which ifi absorbed and KO, which escapes; hence it is evident that even if the lead-compound really contained NO, the latter liberated in presence of the acetate of lead then formed mould be instantly decomposed as above stated.When the product obtained by- passing NO into an alkaline solution is supersaturated with an acid stronger than acetic and then tested with a sulphocyanide the deep red is again obtained which it might be iniagincd was due to tlie simultaneous liberation of the NO and NO, and their union to form the bTO from which they were produced; neither is it a conclusive argument against this view that the acids em- ployed were too dilute to liberate nitric acid perceptibly from pure nitrates for in the former case the additional affinity of NO for NO would come into play.It wa8 found however that nitrites how-ever carefully prepared by double decomposition from pure nitrite of silver or by extraction from crude nitrites with alcohol always acted in tlie same manner when treated. with a stronger acid hence it appeared probable that NO really produces the reaction with free hpclrosulphocyanic acid though not with a sulphocyanide and that the reason why a mixture of a sulphocyanide and nitrite remained colourless when treated with acetic acid mas that the latter was a weaker acid than hydrosulphocyanic acid ad not being capable of liberating it the coloration with NO could not occur ; and this was found to be the case for on preparing pure NS,Cy and exposing it together with a sulphocyanide to the vapour evolved from a nitrite and acetic acid the former was instantly reddened while the latter remained colourlem and on adding to the reddened HS,Cj7 a solution of any acetate the dour disap.M2 HADOW OR’ SUT,PEIOCYAHIDES &C. peared in consequence of the HS,Cy entering into combination with the base in preference to the acetic acid and being thus ren- dered incapable of reacting with NO,. The action of NO on salts with weak acids explains also its behaviour with sulphoc~7an- ides; for here as in other cases we may conclude that it is split into NO and NO, the former liberating HS,Cy which is then in a condition to be coloured by the latter.Hence although sulpho- cyanides serve as a test to distinguish between KO4 and NO in a gaseous mixture it appears that the colour rroduced is really due to the mutual presence of free NO and free HS Cy. The colour does not appear to be due to any decomposition of the HS,Cy for in consequence of the large amount of HCy obtainable by the action of nitric acid on sulphocyanides (which seems to show that the whole action is expended on the sulphur) we must conclude that the very first symptom of decomposition will be the appearance of sulphuric acid for such is the case when a mixture of a sulpho- cyanide chloride of barium and nitric acid are gently heated the instaut a reddish tint appears showing that the nitric acid has under- gone reduction and parted with some oxygen a cloud of sulphate of baryta also appears.This is not the case however immediately when NO is passed into the mixed solutions of a sulphocyanide and a baryta salt the red colour remains some little time before a cloud appears and substances capable of combining with NO such as bases or even alcohol immediately decolorise the mixture the latter thus furnishes an additional means of distinguishing between the colour due to oxides of nitrogen and that due to per- salts of iron. The cornhination therefore which produces the red colour seems to be similar in the feebleness of its character to that of the black compounds which ferrous salts form with NO, which are stated to be destroyed by simply placing in a vacuum.In conclusion it may be observed that the fact of aportion of the sulphur in proteiu compounds being more difficult of detec-tion than the remainder-taken into consideration with the ap- pearance of hydrocyanic acid amongst the products obtained by the action of oxidising agents on albumen &c.,-seems to suggest the possibility that this latent condition of the sulphur may be due to its union with the hydrocyanic acid as sulphocyanide per- haps further combined with the alcohol-radicals corresponding to those acids which likewise appear amongst the products of oxida- tion of protein bodies. The fact of the exiitence of sulphocyanides in the body seems to show that such an explanation is not utterly improtmhle.

ISSN:1743-6893    

DOI:10.1039/QJ8591100174

出版商:RSC    

年代:1859

数据来源: RSC