摘要:

On the ZBasic Carbonatesof Copper. By E'rederiek Field ON adding sulphate of copper to a great excess of solution of sesqriicarbonate of soda no precipitate is obtained until a consi- derable quantity of the copper-salt has been introduced. Even then on gently warming the small precipitate of carbonate of copper is dissolved forming a bright blue solution. When this liquid is boiled for some time a green granular precipitate is obtained the supernatant liquid still holding copper in solution with great tenacity and maintaining its clear blue colour. If the ebullition has not been continued for more than half an hour on filtering the liquid from the precipitate the former is found to be capable of dissolving afurther quantity ofcopper which is preci-pitated as a green powder similar to the last.After very pro-tracted ebullition however the filtrate from tliis last precipitate yields on the introduction of sulphate of copper not a green powder but one of a dense black colour. Composition of the Green Precipitate.-After thorough washing the green compound was dried on a water-bath until it ceased to lose weight and the copper and carbonic acid were determined the water being estimated as loss. I. 11. Copper ........ 57-46 57.21 Carbonic acid ...... 19.45 19.31 This compound is identical in composition with the ordinary green dicarbonate and malachite as shown by the following numbers which for the sake of comparison are placed in juxtaposition with the results obtained in the analysis of a fine specimen of pure malachite from the west coast of Africa and some beau- tiful crystals of native dicarbonate of copper from Chili.cuu ....71.81 Green Precipitate. '71.74 Malachite. 71-69 Crystals. 72-06 Calculated. COz HO (loss) .. 12-45 .. ,. 8.74-.... 19.68 8.58 19.80 8.51 19.82 8.12 100~00 100*00 100*00 100*00 Composition of the Black Precipitate.-This compound after boiling with the strongly alkaline liquid for a considerable time was washed and dried in IL water-bath. FIELD ON THE BASIC CARBONATES OF COPPER. 71 On analysis it was found to consist of 4 equivalents of oxide combined with one of dicarbonate of copper or which is the same thing 6 of oxide of copper and 1of carbonic acid as the following numbers will show Found.Calculated. I. 11. CuO .. + , .. 91-42 91.39 91.60 CO .. .. .. 8.44 8.51 8-40 Very long protracted boiling of the alkaline liquid was necessary to convert this compound into oxide of copper. Suspended in pure boiling water it is decomposed in a few minutes. When powdered malachite is introduced into boiling water the mineral blackens in a few minutes and after half an hour's brisk ebullition is entirely converted into black oxide. Artificially prepared dicarbonate suffers the same reaction. When equivalent proportions of sulphate of copper and carbonate of soda are clissolved in water the ultimate result is the same although much retarded by the sulphate of soda in solution. I could obtain no decomposition of either the mineral or the artificial compound in a boiling solution of chloride of sodium.When sulphate of copper is gradually added to a strong solution of carbonate of soda an immediate blue precipitate occiirs on the addition of the first few drops unaccompanied by effervesence and by the further introduction of the copper-salt no more pre- cipitation takes place but a dark blue solution is formed. When this is heated it immediately darkens owing to the formation of a black powder. The addition of sulphate of copper to the super- natant carbonate of soda causes a bright temporary blue colour which is almost instantaneously changed into the black. Washed and dried this substance was found to contain I. 11. CuO 91.49 91-52 CO 8-38 8.41 and thus to have the same composition as the one mentioned above viz 4Cu0,2Cu0,C02.This highly basic carbonate can be boiled with carbonate of soda for many hours without decom- position ;suspended in pure boiling water it is speedily decomposed. Action of Carbonate of Soda upon Dicarhonate of Copper. When a solution of carbonate of soda is heated even only to the tem- perature of lZO"F and powdered malachite or artificial diearbonate is introduced decomposition quickly takes place as is shown by the darkening of the compounds. An evolution of carbonic acid always accompanies the reaction. A few minutes boiling yields the compound 4Cu0 2Cu0,C02. It may further be remarked that when dicarbonate of copper either artificially prepared or as malachite is boiled with a solution of sesquicarbonate of soda it is dissolved and a blue solution is formed which is not decomposed after long ebullition sesqui- 72 FIELD ON THE BASIC CARBONATES OF COPPER.carbonate of soda containing carbonate of copper in solution appearing to resist the action of heat far more stroirgly than it does in the absence of the latter metal. When sulphate of copper is added to a mixed solution of a sesquicarbonate and sulphite of soda no precipitate is formed. An easy and safe method of de-oxidation consists in adding a mixture of about equal parts of sesquicarbonate and sulphite of soda to a hot solution of a proto-salt of copper. After heating for some little time the introduction of a slight excess of hydro-chloric acid produces a solution which is perfectly colourless and gives with potash the clear orange precipitate of the suboxide and with ammonia no blue shade if the air be carefully excluded. With regard to the precipitation of copper from its vayious salts as protoxide it is much better to employ hypochlorite of soda than caustic potash. The precipitate subsides more quickly and is infinitely easier to wash.

ISSN:1743-6893    

DOI:10.1039/QJ8621400070

出版商:RSC    

年代:1862

数据来源: RSC

摘要:

Contributions to fbe History of the Phosphorus Bases. By Auyusfus William Hofmann F'.R,S [Abstracted from ft series of papera read before the Royal Society June 21,1860.J SECOND MEMOIR. Theory of Diatomic Bases Diphosphonium-Compounds. INsurveying the rich harvest of discoveries which of late years have rewarded the exertions of chemists with reference to their general effect on the progress of the science we cannot avoid recognizing as one of the most valuable amongst these acquisitions the development of the theory of polyatomic compounds. Seldom has a theory diffused a clearer light on previously established facts or exerted a more fructifying and inspiring influence on the labours of chemists. First coming into notice in the classical researches of Graham and Liebig on the polybasic acids and afterwards extended and generalized by the experiments of Ge rh a rd t and Williamson it has acquired in Berthelot's beautiful investi- gation of glycerin a new field of discovery the active cultivation of which has already brought to maturity a great variety of fruits.An important step in the development of these ideas was made by H. L. Buff in showing that dibromide of ethylene can be con- verted into a corresponding sulphocyanate and in the conclusions which he drew from this observation until in the brilliant experi- mental researches of Wurt z the doctrine of polyatomic corn-pounds has received its clearest and most elegant expression. Considering the untiring activity with which chemists have devoted themselves to the study of the polybasic acids and within the last few years of the polyatomic alcohols it cannot but appear remarkable that so little attention should hitherto have been bestowed on the polyacid bases.It is true that we are already in possession of many valuable observations relating to these bodies ; but they are isolated and the facts which they have established can scarcely- be looked upon as more than accidental acquisitions. Regarded in the scientific sense as a class and in their relations to other groups of bodies the polyatomic bases have hitherto been left without examination. Respecting the constitution of these compounds and the con- ditions under which they would be produced no doubt could be entertained. For as from a single molecule of water a monatomic alcohol a monobasic acid or a monacid base can be produced according to the nature of the monatomic radical by which the hydrogen is replaced so likewise must it be possible by a proper VOL.XIV. 0 selection of polyatomic radicals to link two or more molecnles of water so as to form one molecule of n poly~cidbase just as the introduction of other polyatomic radicals gives rise to the formation of polyatomic alcohols or polybasic acids. It remained only to submit these ideas to the test of experiment. Material for building up this group of bodies appeared to present itself unmistakeably in the chlorine- bromine- and iodine-com- pounds of ethylene and its homologues. Having succeeded some years ago in converting the corresponding ethyl-compounds by the action of ammoniil into the rnonacid ethyl-bases I xas justi-fied in expecting that by treating the ethylene-compounds with ammonia diacid bases might he formed.Respccting some of the bodies which are produced in thcse reactions investigations had already been published by CloGz,* and more recently by Natan- son,i whose results appeared at first sight to give but little encouragement to any such attempt. But a careful examination of these researches soon convinced me that at the time when they were undertaken che mica1 knowledge had riot sufficiently advanced to afford a correct interpretation of the results elicited. 1 have oncc more studied them reactions aud have obtained experimental confirmation of the correctness of my anticipations.But the action of ammoni;t on the chloride bromide and iodide of ethylene presents uriespected complications quite independent of those indicated by theory and for which I was not altogether prepared. Consider for a moment the manner in which the reaction between ammonia and a diatomic bromide-dibromide of ethylene for instance-may take place Just as bromide of ethyl acting as it does on a single moleculc of amnionin gives rise to the formation of the four bromides so likewise may dibromide of ethylene acting on two molecules of ammonia be expected to produce four diatomic bromides viz.-These however are by no means the only compounds which in accordance with OUF present conception of diatomic compounds may be formed in this reaction.It appears from the researches of Wurtz th%t dibromide of ethylene does not pass into ethylene-nlcdhol at ;z single bound but * Instit. 1853,p 213. + Ann. Ch. Pharm. xcii. 45 and xcviii. 291. 2 H=l; 0=16; 5~32;C=12,&~. IIISTOltY OF THE PFfOSPfIOItUS BA8T.S. that there exists ail intermcdiate member of the series still con-taining half the bromine. (C2H4)” {FO (‘2’’4.)’’ fc,H,>” { ;; { Eg Dibromide of Jntermed ate Ethylene-Ethylene. Bromide alcohol. There could therefore be no doubt that dibromide of ethylene mould under certain conditions likewise react vith ammonia as a monatomic compound giving rise to another wries of bodies in which the hydrogen would be more or less replaced by the mon- atomic radical C,H,Br viz.-[( C2H4Br) I-I,Jd] Br [(C2H,Br),I-I,N] Br c(C2ww3H N1Br, and [(C,H4Br) N] Br.Further if the reaction took place in presence of water it was to be expected that the bromine wholly or partially eliminated as hydrobromic acid would be replaced by the molecular residue of the water ; and thus independently of any mixed compounds con- taining bromine und oxygen a series of salts might be looked for in which a molecule C,W,HO =C2H,0 would enter moiiatomically viz.-[(C2N50) H3N1 Br> [(C2H5O),H2N]Br [(C2H50)3H N1ur, and [(C2E150) N] Br. Lastly remembering the tendency exhibited by ethylene-corn- pounds to resolve themselves in presence of alkalies into vinyl-compounds it appeared not improbable that a fourth series of bodies would likewise be formed viz.-[(CgWJ H3NI Br [(C2I-13) 2H2N1 Br C(C,H,),H Nl Br and C(C2H314 NIBr ; and thus was presented the not very inviting problem of separating from a great mass of bromide of ammonium no fewer than sixteen different bases.In the experiments on the action of dibromide of ethylene on ammonia and its homologues which I intend to publish in a special paper I have indeed by no means met with the whole of these compounds; but in place of the deficient members of the groups new products have made their appearance whose forma-tion in the present state of our knowledge could scarcely have been predicted Without entering into details respecting these products I will merely observe that I was induced by the compli- cation of‘ this reaction to subject dibromide of ethylene to the 62 A.w. HOFMANN’S CONTRIBUTIONSTO THE action of ethylamine diethylami tie and finally of triethylamine instead of ammonia; for it could not be doubted that with the progressive substitution of ethyl for the hydrogen in ammonia the process wotild be simplified the number of pqssible products of rraction being considerably diminished. Ammonia indeed-omitting secondary products-is capable of prodiicing not less than siztcen compounds whereas ethylamine cannot yield more than twelve diethylamine not more than eight and in the re-action between triethylamine and dibromide of ethylene the number of compounds possible under the most favourable circumstances is limited to four.Experiment has verified this anticipation ;in the same proportion as the substitution advances in the aminonia sub. mitted to the action the number of prodizcts generated diininislics; nevertheless the experiment Yith triethylamine from which I had expected the simplest and clearest solution of my problem did not entirely satisfy me inasmuch as I did not succeed iri obtairiing more than three of the compounds out of thefour which are indi-cated by theory. It was not indeed ti\l I repeated the experiment in the phosphorus-series using instead of triethylainine the cor- responding phosphorus-base that I succeeded in obtaining all the compounds and that the results appeared as the pure expression of theory undisturbed by accidental products.In its reaction with dihromide of ethylene the sharply defined characters of triethyl- phosphine exhibit themselves with aelcome distinctness ; and in the products resulting from the action the peculiar relations between monatomic and diatomic bases become perceptible with a degree of clearness and gencrality such as T have never observed in any similar reaction among bodies of the nitrogen-series. It is the smoothness of these reactions which renders it desirable to commence an account of a more general irivestigation of the diatomip bases with a description of the bodies belonging to the phosphorus- series ETHYLENE-GROUP. Action of Dibrornide of Ethylene on Triethylyhosphine. When these two bodies are brought together in quantities not too large the liquid becomes turbid but no rise of temperature takes place to indicate the occurrence of chemical action.The mixture after being left to itself for a few hours deposits white crystals the formation of which contiiiues till the entire liquid is cmverted into a white saline mass. If the mixture be even gently heated the crystallization takes PJace instantaneously and rz violent reaction sets in which is very apt to project a poition of the resulting salt from the vessel. In operating on rather a large scale in vessels filled with air the heat evolved on agitation in consequence of the oxidation of the phosphorous-base is often sufficient to start the reaction. HISTORY OF THE PHOSPHORUS BASES. In preparing considerable quantities of the white crystals T have thtxefore found it convenient to add to the triethylphosphine twice its volume of ether to mix the ethereal solution with the dibro- mide of ethylene in a flask filled with carbonic acid gas and to heat the mixture in a water-bath the flask being provided with an inverted cooling apparatus so that the vapours which escape may be condensed and returned.Or the misture of triethylphospliinc. dibromide of ethylece and ether may be introduced into long tubes previously drawn out and the tubes after sealing immersed for some hours in boiling water As the value of dibromide of ethy-lene is trifling in comparison with that of triethylphosphine I alF+ays in commencing the study of this reaction used the former substance in excess.The triethylphosphine is quickly fixed by the dibromide of ethylene and the action may be considered as terminated when the presence of the free phosphorus-base in the mixture is no longer indicated by disulphide of carbon. As soon as this point is attained the crystalline bromides may be throwu on a filter the ether allowed to drain ofT and the crystals freed from excess of bromide of ethylene by washing them for a while with anhydrous ether in which they are quite insoluble. The crystals thus obtained dissolve with great facility in water and in ordinary alcohol somewhat less readily in boiling absolute alcohol. This solution on cooling deposits well-developed crystals which sustain a heat of 100°C without decomposition but show a slight tendency to deliquesce in the air.The anaiysis of these crystals and their behaviour with reagents showed unmistakeably that in the action of dibromide of ethylene on triethylphosphine at least two bromides are formed. The determination of the bromine by meaiis of nitrate of silver in the products of different preparations purified by successive crystallizations from alcohol gave percentages of bromine varying from 32.1 to 25-94 On again repeating the crystallization the amount of bromine precipitated by nitrate of silver did not exhibit any further dimi- nution. The complete analysis of the crystals purified by a great number of crystallizations from alcohol has led me to the simple expression C,H,,PBr2= CGH,,P+C2H,Br, whence it appears that the body is produced by the combination of one molecule of triethylphosphine with one molecule of the bromine-compound.Tile purification of the second substance yielding with nitrate of silver a larger proportion of bromine which remains in the mother-liquor of the compound just described is soniewhat com-plicated. As I shall have to return to this body in the description of the individual compounds I content myself in this place with just setting forth the general character of the reaction by quoting the fGrmula deduced from its examination. The analysis of this A. w. HOFMAX’N’S CONTRIBUTIOKS TO IIIE bromine-compound together with those of a whole series of bodies derived from it has led to the formula C,,H,,P,Br = 2C6€I,,P +C,H,Br, showing that the body is a compound of two molecules of trietliyl-phosphine and one molecule of dibrornide of ethylene.These observations are sufficient to establish the peculiar nature of the reaction in question. Tliere are clearly two successive phases to be distinguished according as the bromide of ethylene laps hold of one or two molecules of triethylphosphine; secondary products may likewise be formed nhich for the present may be left out of consideration as 1shall have to allude to them in the course of the memoir. It is however worth nhile to mention in this place that when the experiment is made with pure substances and under the conditions above mentioned the two bromides described are almost the only products of tlie reaction.These two bodies have become the starting-points of two exten- sive groups of compounds which may even now be distinguished as the series of monatomic compounds and the series of diatomic compounds. \c 1 now proceed to the detailed description of the individual members of these series. OF MONATOMIC SERIES COMPOUNDS.MOXOPROSPHONIUM-COMPOUNDS. Salts of Bromet~~iyl-triethy~hos~honiuna. Bromide of BromethyI-triethy~hosphonium.-B y this long name I designate the crystalline substance which is produced by the union of one molecule of dibromide of ethylenc and one molecule of trietliylphosphine. The preparation of this compound has already been given in the prececliiig paragraph. It is the chief prcduct of the reaction when the dibromide of ethylene is in excess.The equation C,H,Br + C,H,,:P = C,H19PBr requires ahont 1 vol. of dibromide of ethylene to 1.5 vol. of triethylphosphine; but even when a larger quantity of the bro- mine-compound is heated with the phosphorus-base either in presence or absence of ether or alcohol we always obtain an appreciable quantity of the second bromide. It is only by allowing an immense excess of dibromide to act at the GO~~OB temperature upon triethylphosphine either in presence or absence of ether that the formation of the second bromide is altogether avoided. In this reaction mhich is not complete in less than twenty-four hours a considerable quantity of gas is evolved which does not appear n lien the substances are heated together.To purify the product 11 hich contains appreciable quantities of the second broinidx it is necessary to crystallizc it at least three or HISTORY OF THE PIIOBPHOltUS BAPES. 79 four times from absolute alcohol; in the last crystallization it is desirable to mix the alcoholic solution with a moderate quantity of ether. The solution if lcft to itself frequently deposits separate well-defined crystals which may he dried without decomposition at loo" and which melt at about 235"C with partial decomposition hydrobrornic acid being abundantly evolved. A simple experiment showed that nitrate of silver precipitates from this compound only part of the bromine. When the liquid filtered from the precipitated bromide of silver was mixed with carbonate of sodium to remove the excess of silver and evaporated the residue when ignited with lime and dissolved in nitric acid gave on addition of nitrate of silver a fresh quantity of bromide of silver.I therefore endeavoured to obtain the entire quantity of bromine by means of recently precipitated oxide of silver a process which I had previously found serviceable in similar cases. The result confirmed my anticipation. Digestion with oxide of silver removes the whole of the bromine and shows that the quantity precipitated by nitrate of silver is only half the total %mount. The analysis* of this substance led to the formula already quoted c H,SP Br,,? the interpretation of which presents no difficulty. The crystals are evidently the bromide of a monophosphonium in which 3 eqs.of ethyl are substituted for 3 eqixivs. of hydrogen the last equivalent of hydrogen being replaced by a secondary radical C2H4Br,which for the present I will call ~o~o~ro~~~~a~e~ ethyl or bromethyl. The molecular formula UCABr) (C,w3Pl Rr represents the constitution of this salt. I have already observed that this bromide is occasionally obtained in tt ell-defincd crystds. They were examined by Quintin o Sella lCSystem monometric (regular). The crystals exhibit the form of the rhombic dodecahedron 110 (Fig. a$).$ They are sometimes elongated so as to present the aspect of dimetric crystals as in Fig. 29. Sometimes it even happens that one of the faces i 1 0 is much more developed than the parallel face I,i 0 (Fig.30)) so that scarcely more than half the crystal (Fig. 29) appears to exist. Sometimes the faces exhibit strize parallel to the adjacent edges of the rhombic dodecahedron. * The details of the analytical determinetion are given in the original papers published in the Philosophical Transactions for 1860. t H=l; 0=16; S=32; C=12. 2 The figures are numbered consecutively with that in Dr. Hofmann's former paper on the phosphorns bases vol. xiii p. 289 of this Journal. A. w. HOFMANN'S CONTRIBUTIONS TO THE Fig. 28. Feb. 29. Fig. 30. Lustre fatty. Hardness inferior to that of gypsum. The crystals have no action on polarized light." By treating the bromide with silver-salts in the cold the bromine external to the phosphonium- metal is replaced by the acid-radical united with the silver while the bromine belonging to the yhos- plionium remains untouched.In this manner we obtain the salts of the new metal which exhibit an inclination to unite tvith excess of the silver-salts in the form of double compounds The chloride and the nitrate prepared from the bromide by the action of cliloride and nitrate of silver are extremely soluble in water and alcohol and crystallize indibtinctly The subhate forms long white crystalline needles likewise very soluble in water and alcohol. It is very easily obtained by the action of sulphuretted hydrogen on the double salt which is formed by treating the bro- mide with sulphate of silver ; on adding alcohol and ether to the concentrated liquid containing free sulphuric acid it is precipitated in crystals.The sulphate treated with iodide of barium yields the iodide a salt which dissolves sparingly in water and crystallizes in scales of a pearly lustre. I have not examined these salts more particularly as they scarcely present any theoretical interest and as the composition of the bromide mhich forms the starting-point of tlie series is sufficiently corroborated by the analysis of the platinum- and gold- salts. PZatinum-saZt.-The chloride obtained by digesting the bromide with excess of chloride of silver is mixed with dichloride of plati- num when the platinum-salt is deposited on cooling in light orange-yellow prisms frequently an inch in length. This salt is somewhat sparingly soluble in cold more readily in boiling water and may be crystallized without decomposition.During the re-crystallizations this salt under circumstances not yet clearly made out is occasionally obtained in crystals of an octahedral habitus This platinum-salt though somewhat sparingly soluble is nei ertheless essentially different from the platinum-halt of the HISTORY OF THE PHOSPHORUS BASES. diphosphonium to be described hereafter which accompanies the bromethyltriethyl-phospl~onium. The latter is nearly insoluble in water and is precipitated from tlie most dilute solutions. This character forms a means of testing the purity of the monophos- phonium-bromide in the succession of crystallizations to which it has to be submitted for the sake of purification.The salt is pure when the dilute solution after being treated with chloride of silver no longer gives a precipitate with dichloride of platinum. The ulatinurn salt contains :-C8H19BrP Pt C1 = [(C,H,Rr) [(C,H,),P] Cl Pt C1,. The crystalline form was likewise determined by Quin tino Sella. Fig. 31. I' System monoclinic :-100 10 kli5'59'; 001 10 1,= 33' 3'; 010 1 1 1=60° 37'. Forms observed :-iiw loo 010 110 101 ioi 011 11 1 i 11 2 11 (Fig. 31). Fig. 32. Fig. 33. Fig. 34. Combinations observed :-11 0 0 11 100; 101 701 (Figs. 32 33). 110 011; 100 ill ioi (Fig.34). 110 011; 100 7 11 301 211 (Fig.35). 110 111; 100 -1 0 I 0 1 I 11 1 (Fig. 34. 110 011 100 111; 101 ill fl I (Fig.37). 110 011 100; 010 011 301 211 (Figs.38,39).Fig 35 Fig 36 The fdces 0 1 1 are often very irregularly developed as seen in Figs. 32 33 and 38 39 under these circumstances some of the faces of the forms 1 1 1 111 % 1 1 aie apt to disappear as may be seen in Figs. 38 and 39 Fig. 37 Fig. 38. Fig. 39 ..........." I Cleavages 100 110 Colour orange with a tint of yellow in minute and of red in larger crystals. The plane of the optical axes is parallel to the axis of symmetry [o 1 03 for rings aie observed across the faces of the prism 1 10 symmetrically with [0 101 " GoEd-saEt.-Light yellow needles difficultly soluble in cold water recrystallizable from boiling water containing C,HlgBr P Au. C1 = [(C,H,Br) (C,H,),P] Cl, Au C1 I have in vain endeavoured to prepare the hydrate C H2 BrP 0 = c('2 H4 Br) ('2 H5)3 '1' 0 Hi-belonging to these salts HISTORY OF TIIE PROSPIIORUS BASES.In quoting the analysis of the bromide I have already mentioned that this salt when treated with oxide of silver gives up the whole of its bromine. On mixing the caustic liquid filtered from the silver-salt with hydrochloric acid and dichloride of platinum we no longer obtain the sparingly soluble platinum-double salt crystal- lizing in the characteristic needles; but the liquid after being considerably concentrated by evaporation yields well-defined reddish-yellow octahedra belonging to another base. An exactly similar result is obtained OD attempting to separate the base from the sulphate by means of baryta.After filtering off the sulphatc of barium there remains a strongly alkaline liquid which liliewise yields only the octahedral platinum-salt while the presence of bromide of barium in the solution indicates the transformation of the original molecular system. The elimination of the second equivalent of bromine by silver-salts which tales place instantly and completely in alkaline liquids may likewise be effected by continual ebullition in neutral and even in acid solutions though always slowly and incompletely. If the bromide be precipitated by excess of nitrate of silver the filtered liqiiid on being boiled arid evaporated dcposits a fresh quantity of bromide of silver; but in most cases even after long-continued boiling a considerable quantity of bromine remains latent and may be immediately recognized by again filtering the liquid and slightly supersatu- rating it with ammonia the whole of the remaining bromine being then precipitated as bromide of silver.This deportment furnishes in fact a characteristic distinction of the bromethylated bromide by which this substance may often be conveniently recognized. It deserves to be remarlred that the fixed caustic alkalies exert but a slight action on the bromethylated bromide; the compound is precipitated by the alkalies from its coid aqueous solution in the crystalline state and without decomposition and it is only after some time that alterations take place probably affect- ing its intimate constitution. The nature of these alterations has not yet been made out.The crystals may be boiled for some time with alcoholic solution of potassa without decomposition. The bromide lilrewise suffers no alteration by continued digestion with water or alcohol at 100". SALTSOF OXETHYL-TRIETHYLPHOSPHONIUM Iodide.-When the caustic liquid produced by treating the bromide of bromethyl-triethplphosphoriiumwith oxide of silver is neutralized with hydriodic acid and the solution evaporated an iodide is obtained which crystallizes in needles and dissolves very readily in water and alcohol. The finest crystals are obtained by mixing the alcoholic solutioii with ether till it becomes opalescent and then allowing it to crystallize. If too much ether has been added the new iodide is precipitated as an oil which solidifies but A.W. IIOFMANN'S CONTRIBUTIONS TO THE slowly to a crystalline mass. The salt becomes coloured at loo" and must therefore be driedfor analysis ir8 vacua It was fouiid to contain :-C,H,,OPI = C~C,H,O)I(c2H5)3p~1. The transformation of the broniethylated phosphonium takes place therefore exactly as might be expected from analogy the bromine being eliminated as bromide of silver and its place being taken by the molecular residue of the water :-Hydrate.-The caustic solution of the oxide exhibits the usual characteristic properties of this class of bodies. Over sdphuric acid the solution thickens to a syrupy extremely deliquescent mass from which the base separates in oily drops on addition of potassa. Its decomposition by heat is characteristic; at a rather high temperature it is resolved into oxide of triethylphosphiue ethylene and water :-[('2 H5 O) ('2 H5)33] 0 = (C HJ3P 0 + C H + H 0.The oxide of triethylphosphine was identified by the preparation of its platinum-salt; the ethylene by converting it into the bromide. The above equation represents the final result of the action of heat ;this final result however is preceded by several intermediate changes to which I shall return in a subsequent section of this payer. Bromide.-Extremely soluble. Dries up over sulphuric acid to an indistinct crystalline mass. Chloride.-This compound resembles the bromide in every respect. Both these salts readily form double compounds with iodide and bromide of zinc.The ellloride under the influence of pentabromide and pentachloride of phosphorus undergoes remark- able transformations to which I shall presently recur. Perchlorate.-Laminae somew hat sparingly soluble in cold water I have not analysed any of these salts inasmuch as the com- position of this series of compounds is moreover sufficiently established by the analysis of the platinum- and gold-salt. PZuatinurn-suZt.-The alkaline solution from which the iodide was obtained yields when saturated with hydrochloric acid mixed with dichloride of platinum and evaporated the above-mentioned platinum salt containing- C H2 0 P Pt Ctl = [(C H5 0)(C H5) P] Cl Pt Cl,. This salt is easily soluble in boiling water and may be recrys- tallized without decomposition.It forms splendid octahedra which were measured by Quintino Sella HISTORY OF THE PHOSPHORUS BASES. Fig. 40. ‘‘ System rnonometric :-Form observed :-111 (Fig. 40.) No sensible influence on polarized light. Colour orange.” GoZd-salt.-Golden-yellow needles sparingly soluble in cold readily in boiling water in a quantity of boiling water not suffi-cient to dissolve them they fuse to a transparent yellow oil. Not decomposed by recrystillieation. Precipitated by trichloride of gold from a moderately concentrated solution of the chloride. Analysis .led to the formula C 0 P Au Cl = [(C N,0) (C H,) P] Cl AU Cl,. I Lave already alluded to the decomposition which the chloride of the oxethylated phosphoniurn undergoes under the influence of pentabrornide of phosphorus.The two bodies act iipon one another with great violence oxybromide of phosphorus and hydrobromic acid are evolved and the residue is found to contain the chloridz of the bromethylated phosphonium from which the oxethylated compound was originally produced. Nothing is easier than to obtain experimental proof of this transformation which is of coiisiderable theoretical interest. After the oxybromide and the excess of pentabromide have been removed as completely as possible by evaporation the remaining liquid yields on addition of dichloride of platinum a sparkgly soluble still impure platinum-salt which after mashing may be decomposed by sulphuretted hydrogen and thereby purified. If the chloride thus formed be precipitated with excess of nitrate of silver and the nitrate of the base filtered from the chloride of silver be mixed with ammonia and gently heated a copious precipitate is immediately formed consisting of bromide of silver.This reaction is characteristic of the bromethplated body. More-over on mixing the solution of the nitrate freed from silver with dichloride of platinum and recrystallizing the platinum-precipitate from boiling water the liquid yields on cooling the splendid needles of the platinum-salt of the bromethylxted triethylphos- yhonium. The analysis of this salt mas omitted partly because no doubt could be entertained respecting its nature and partly became I had occasion to establish by a nnrnber-as will be A.w. HOFMZANX'SCONTRIBUTIOSSTO THE noticed hereafter-the nature of the precisely similar reaction between chloride of oxethyl-triethylphosphonium and penta-chloride of phosphorus. Thus it is seen that the niolecular group C,H50 which is supposed to replace the hydrogen in the salt sufI'ers under the influence of pentabrornide of phosphorus alterations exactly similar to those which it would have undergone under similar circumstances when conceived as a constituent of alcohol. If we consider the facility with which the bromethylated phos- phonium is converted into the oxethylated compound by the action of oxide of silver and the simple re-formation of the first- mentioned body by means of pentabromide of phosphorus a great variety of new experiments suggest themselves.In reviewing the relations which obtain between the bromethylated and oxethy- lated phosphoniums who could fail to perceive that the two hydrogen-replacing radicals which constitute the difference between these two organic metals stand to one another in the same relation as bromiclc of ethyl and alcohol or bromide of acetyl and acetic acid ? But if this be so what a number of new bodies docs this coxisideration bring iuto view even if we limit our calcu- lation to the transformations of which the molecular group C2€I,0 in alcohol is susceptible ! As yet I liavc scarcely penetrated into this new field of inquiry and I must be satisfied to quote a single experiment which exhibits the above-mentioned bodies in a new light.The salts of bromethylated and oxethylated triethplphoo-phonium may be regarded as tetrethylphosphonium salts in which an atom of hydrogen is replaced by bromine and the radical H 0 respectively Bromide of Tetrethg.lphosphonium ' [ C2H4H) (C2H5)3P1Br, Rromethylitted triethylphosphonium [(C,H,Br) (C,H,),P] Br Oxethylated triethylphosphonium . [(C,H,HO) (C,H,),P] Br and the question arose whether the bromethylzted salt might not be converted by a simple process into the tetrethylphos-phonium-compound. This transformation may indeed be effected without the slighest difficulty. On acidulating the solution of the bromethylated bromide with sulphiiric acid and digesting it with granulated zinc the bromine is eliminated in the form of hydro-bromic acid its place being filled up by one equivalent of hydrogen [(C,H,Br) (C,W,),P] I3r + 233' =HBr i-[(C,H,),P] Br.By decanting the liquid from the excess of zinc and treating it wit11 oxide of silver oxide of ziiic bromine and sulphuric acid are removed and a solution of oxide of tetrethylphosphonium is obtained which when mixed with hydrochloric acid and dichloride HISTORY OF THE PHOSPIIORUS BASES. of platinum ,yields well-developed octahedra of the platinum-salt of tetrethylphosphonium. The chloride obtained in the analysis was converted by suc-cessive treatment with oxide of silver and hydriodic acid into the corresponding iodide. This characteristic salt a,ppeared on careful comparison exactly similar to the iodide of tetrethylphosphonium prepared in the ordinary way.Here then we bave an instance of the direct reproduction of an ethyl-compound from a body of the ethylene-group by a simple process of reduction. Similar transformations woiild doubtless succeed in many other cases and this is perhaps a fitting opportunity of directing attention to the interest which the employment of this reaction would have in connection with the intermediate hydrochloric glycol-ether discovered by Wur t z. Probably this compound when subjected to the action of nascent Iiydrogeii would be directly converted into alcohol C,H,C10 C,H@ ; and when considered with reference to this decomposition would aBpettr as monochlorinated a1 coh01. I& It R as chiefly the facility with which a tetrethylphosphonilam- compound may be obtained from the bromethylated bromide that induced me to designate the hydrogen-replacing molecules C,H,Br and C,H,O which we meet with in the compounds above described as bromet?byZ and oxethyl.I was anxious to submit the ideas which guided me in the selection of these terms to the test of experiment. We know from the experiments of Regnault that dichloride of ethylene and monochlorinated chloride of ethyl are essentially different bodies; and not less distinct are dibromide of ethylene and monobrominated bromide of ethyl which I have obtained in the course of these experiments by the action of bromine on bromide of ethyl. But on the other hand the allied members of these two pairs of bodies are so closely related to each other that under the influence of powerful reagents they not unfrequently yield exactly the same products of transformation I may here refer especially to an interesting experiment of Beilstein who has shown that dichloride of ethylene and mono- chlorinated chloride of ethyl when treated with alcoholic potassa undergo the same decomposition both these compounds give up hydrochloric acid being converted into chloride of vinyl.The denomination bromethyZ-triethyZphosp?r,onium,which I have adopted for the metal produced by the action of dibromide of ethylene on triethylphosphine involves to a certain extent the assumption that this body might under favourable circumstances 88 A. W. IJOFMANN'S CONTRIBUTIONS TO THE be produced also by the mutual action of triethylphosphine and monobrominated bromide of ethyl.In a subsequent chapter of this inquiry I shall have an opportunity of showing how far this assumption is established by experiment. SALTS OF VINYL-TRIETHYLPHOSPHONIUM. In tracing the history of the salts of bromethyl-triethyl-phosphonium I have mentioned that these substances lose their 'Latent bromine though slowly when boiled with silver-salts. I was curious to ascertain whether this reaction involves the same metamorphosis that the bromethylated body undergoes under the influence of oxide of silver. In the anhydrous condition the bromethylated bromide act8 but slowly on acetate of silver. In the presence of alcohol or water the reaction is rapidly accornplished at 100"C.The liquid filtered from the bromide of silver yields no further precipitate on addition of ammonia showing that the whole of the bromine is eliminated. When evaporated with hydrochloric acid the liquid abundantly evolves acetic acid. After sufficient concentration it yields with dichloride of platinum a fine octahedral salt which may be purified by crystallization. This salt contains C,H,,PPtCl = [(C,H,)(C,H,),PJCl PtCl, It is thus seen that the action of silver-salts-at all events of acetate of silver-upon the bromethylated bromide differs from that of oxide of silver. While the latter gives rise to the formation of an osethylated phosphonium the former produces a phosphoretted metal in which three atoms of ethyl are associated with one atom of the radical C,H, which may be termed vinyl.The product then which is formed by the action of acetate of silver upon the bromethylated bromide is the acetate of vinyl-triethylphos-phonium I have been satisfied to establish the formation and composition of the vinyl-compound by a careful and frequently repeated analysis of the platinnm-salt which had been obtained from the products of four different operations. The salts of vinyl-triethyl- phosphonium resemble the oxethylated compounds. I have prepared the iodide which crystallizes but is extremely soluble even in absolute alcohol. The formation of the vinyl-compound was observed in several other processes which may here he briefly mentioned although I must state at once that the experimental evidence on which these observations are based is less conclusive.The oxethylated compoiind differing from the vinyl-triethyl- HISTORY OF THE PHOSPHZTCUS BASES. phosphoninm-salt simply by the elements of one molecule of water which the latter contains less the question naturally sug-gested itself whether under the influence of heat the oxethylated compound might not be converted into the vinyl-body. The results of two experiments appear to answer this question in the affirmative. In one case the bromide of bromethyl-triethyl-phosphonicm had been boiled for a considerable time with oxide of silver. In another experiment a concentrated solution of the oxethylated base was evaporated over an open flame un?il a very appreciable quantity was en tirely decomposed.In both cases it was proved by analysis that the oxethylated base had been transformed into the vinylated compound. In a third experi- ment however in which the temperature was not allowed to rise above 150° the oxethylated compound was not altered. The vinyl-compound appears to be formed also by the action of heat upon the bromethylated bromide Torrents of hydrobromic acid are evolved and the residue yields after treatment with chloride oE silver on addition of dichloride an octohedral platinum -salt. The decomposition is however completed only with difficulty. The evolution of hydro- bromie acid continues for hours even when the salt is kept at a temperature (between 235O and Z50°) at which considerabk quantities are entirely decomposed.I have thus been prevented from procuring an amount of the salt sufficient for its identifica- tion with the vinyl-compound obtained by the action of acetate of silver. Vinyl-triethylphosphonium-saltsare formed in one or tm otbcr reactions which will be noticed in subsequect paragraphs of this inquiry. OF DIATOMIC Cors~ourj~s. SERIES COMPOUNDS.DTPHOSPHOWXUM Salts of Ethylene-t.,exethyl-d~hosphonium. Di2iromide.-The occurrence of this salt among the products of the action of dibromide of ethylene on triethylphosphine has already been mentioned iu the introduction to the experimental part of the memoir. On bringing together the materials in the proportions indicated by the equation C,H,Br + 2C6H,,P == C,,H,,P,Br2 that is to say one volume of dibromide of ethylene and three volumes of the phosphorus-base the diatomic compound is obtained nearly in the theoretical quantity.It is distinguished VOL. XIV. H A. w. ROFM.~PU”’SCONTRIBUTIONS TO TIIE from the monatomic product of the same reaction by its much greater solubility even in absolute alcohol from which it separates only after almost complcte cvaporation in ncedlcs wliicli are permanent in the air. In ether this salt is insoluble as are in fact most of the bromides of the phosphorus-bases both mona-tomic and diatomic. The dibromide obtained by the direct actioii of dibromide of ethylene on triethylphospliine always contains a mall quantity of the monatomic bromide from which it can only be purified with great difficulty.And further if the dibromide of ethylene has not been carefully purified from adhering hydro- bromic acid the resulting salt is likewise contaminated with traces of the extremely soluble hydrobromstc of the phosphorus-base the presence of which likewise interferes very much with the purification of the product. Lastly the formation of oxide of triethylphosphine can never be entirely avoided even when the operation is conducted in an atmosphere of carbonic acid. To obviate these. inconveniences the compound submitted to analysis was prepared by saturating the hydrate to be presently described with hydrobromic acid. The simplest expression of the results obtained irr the analysis of this compound is the formula C7P-I17PBr; its formation however and its deportment fully to be discussed in the following paragraphs prove unmistakeably that this expres- sion must be doubled and that the weight and composition of the molecule of this body is represented by the formula On comparing the composition of the two bromides which are formed from dibromide of ethylene by the fixation of one or two molecules of triethylphosphine it could scarcely be doubted that the monatomic compound even when already formed must still be in a condition to take up the second molecule of triethylphos-phine and thus to pass into the diatomic bromide.The correct- ness of this supposition is easily established by experiment. Thc monatomic bromide acts strongly even at ordinary temperatures on a fresh quantity of the phosphorus-base being transformed with evolution of heat into the diatomic compound C,H,91?Br + C6H,,P = C14H34P2Br2.In presence of alcohol and at looo the reaction is completed in a few seconds. With lively interest have I followed up the result of this simple experiment for its success obviously pointed to a source from which an almost incalculable number of diatomic compounds of the most varied composition might be obtained. HISTORY OF THE PHOSPHORUS BASES. For this reason I have not omitted to establish by numbers the conversion of the monatomic into the diatomic bromide and in the following sections I shall have frequent occasion to quote results which leave no doubt as to the facility of this transfor- mation.The moleeizlar constitution of the new bromide is satisfactorily represented by the formula The salt is derived from a diatomic metal a diphosphonium in which 6 equivs. of hydrogen are replaced by 6 equivs. of ethyl and the remaining 2 equivs. of hydrogen by the radical ethylene indivisible under the given circumstances. It is the diatomic character of the ethylene that links together the two molecules of triethylphosphine and gives to the new molecular system the necessary stability. The dibromide is very easily attacked by silver-compounds and in this manner an extensive series of very sharply characterized diphosphonium-salts may be obtained many of which crystallize remarlcably well. In these reactions ho\yever a tendency towards the formation of dogble compounds is frequently observed and hence it is for the most part better to prepare the salts by treat- ing the free base with the corresponding acids.In examining the dibromide I have made some observations which I may take an opportimity of pursuing further by and by. When the aqueous solution of this salt is mixed with bromine- water very beriutiful yellow needles are immediately separated consisting of a polybromide. These needles may be recrystallized from boiling water but apparently not without decomposition. They have but an ephemeral stability. On boiling the compound bromine continues to be evolved and ultimately the original bromide is left behind. Polybromides of exactly similar character are formed by the action of bromine on the bromides of all the ammonium- and phosphonium-bases that I have examined.I have already pointed out that in fixing one molecule of tri-ethylphosphine to form the compound dibromide of ethylene exhibits a deportment which might have been expected from bromide of bromethyl with which it is isomeric. It was of some interest to examine experimentally the behaviour of triethylphosphine with monobrominated bromide of ethyl. This substance hnd never been prepared. I have obtained it together with the dibrominated bromide of ethyl (C,H3Br2)Br, by submitting bromide of ethyl to the action of dry bromine under pressure at a temperature of 1800 C. Brominated bromide H2 A. W. HOFMANN'S CONTRXBUTIONS TO TIIF of ethyl is a heavy aromatic oil bailing at 110" C.and conse-quently differing altogether from dibromide of ethylene which boils at 130"C. and with which it is isomeric. The brominated bromide attacks the phosphorus-base much more slowly than tile dibromide; the final resillt however is exactly the same the bromide of the bromethylslted monophosphonium and the dibro- mide of the eth ylene-diphosphonium being produced. The former of these salts is obtained in comparatively small quttntity and I was therefore unable to identify the compound in question with the bromethylated bromide obtained by means of the ethylene- compound otherwise than by the characteristic reaction with silver-salts mentioned in an earlier paragraph of this paper.The diphosphonium-compound on the other haid is easily produced in sufficiently large quantity by means of brominated broniide of ethyl. I had no difficulty in establishing the absolute identity of this compound with the product obtained from dibromide of ethylene by ft careful comparison of the chemical and physical properties of the substances ad moreover by the analysis of B di-iodide and a platinum-salt derived from the bromide-of-ethyl- derivative. Dihydrate.-The free base is easily obtained by the action of oxide of silver on the dibromide or better on the di-iodide which latter is tf all the diphosphonium-mmpounds of this class the easiest to cbtain in the pure state. If the alcoholic solution of the crude dibromide be used in this experiment the first; portions of oxide of silver added to the liquid are conipletely dissolved and the solution which has already become alkaline deposits a white crystallized double compound of the dibromide with bromide of silver which however is complctely deccrnposcd by further addition of oxide of silver and dilution with water.In this manner there is produced an extremely caustic nearly odcur-less liquid having a strongly alkaline taste and exhibiting the bitterness which is so often observed in the analogous bodies of the nitrogen-series. In other respects the base exhibits the pro- perties which characterize the hydrates of tetrethylphosphonium~ and tetrethylammonium .t The solution when evaporated in an open vessel rapidly absorbs carbonic acid and ultimately yields a semi-crystalline mixture of dihydrate and carbonate.\Vhc:1 evaporated in vacuo over sulphuric acid the caustic solution gradually dries up to a syrupy extremely deliquescent mBss mhich exhibits no traces of crystallization. On mixing the higllly concentrated solution of the dihydrate with solution cf potassx, the base is sepalsated from the liquid in oily drcps which are however readily dissolved on addition of water. The free base like the correspondingmonopliosphonium-and even monamrnonium- * Phil. Trans 185'7 Part 11. p. 683. Chem. Foe. Qu. J. xi. 65. .t. Phil Trans. 1851 Part. IT. p. 35'7. Chem. SOC.Qu. J. iv. 304. XIISTORY OF THE PHO$PRORUS BASES. compounds cannot therefore be obtaizned in a state fit for analysis ; its formation however as well as its conversion into a series-of well-defined salts corresponding to the dibromide characterize it as an oxide derived from the type,- as the hydrated dioxide of ethylene-hexethyl-diphosphonium Complicated as the construction of this compound must appear, it is remarkable for its stability.The solution may be boiled and considerably concentrated upon the water-bath without decom- position and remains unchanged even when exposed for some time under pressure to a temperature of 150’; indeed the decompocition of the hydrate does not begin till the liquid is evaporated to dry-ness. The changes which this compound suffers under the influ- ence of higher temperatures are not without interest. They are rather intricate and I propose therefore to devote a special para- graph to their study.In its deportment with metallic salts the hydrate of the diphot- phonium closely resembles the fixed alkalies as may be seen from the following Table :-Deportment of the Igydrats of Diphosphonium with reagents. Barinm-salts Strontium-sa’ts White precipitates of the hydrates Calcium-salts Magnesium-salts I Aluminium-salts White precipitate of hydrate of aluminium soluble in excess of the precipitant. Chromium-salts . Greer precipitate of hydrate of chroaium sohb!e in an excess of the precipitant and reprecipitated on ebullition. Nickel-salts . .Apple-green precipitate of the hydrate. Cobalt-Salts . . Blue precipitate of the hydrate. Iron-salts -Pervosum .. Greenish precipitate of the hydrate. Ferricum . Reddish-brown precipitate of the hydrate. Zinc-salts . . . Khite gelatinous precipitate of the hydrate insoliible in excess. Lead.salts . . . White amorphous precipitate of hydrate of lead soluble in excess. Silver-salts . .Black-brown precipitate of oxide of silver. Mercury-salts :-Mmw.osum . Black precipitate of the suboxide. Mercuricum . Yellow precipitate of the oxide. Copper-salts . . Light blue precipitate of the hydrate insoluble in excess in presence of sugar the precipitate dissolves in excess forming an azure-blue solution from which if glucose has bzea employed a red precipitate of suboxide of copper scpnratcs on ebullition. ~~~~~~~~~~} White precipitates of the hydrates. A w.HOFMANN’S CONTRIBUTIOXSTO TIIE Tin-salts Stannosurn :-Chloride containing free hydrochloric acid .. . . Whitc aeicular precipitate of a doublc compound. Stannicufm:-Chloride . . White gelatinous precipitate extremely soluble in excess. Antimony :-Trichloride . . White acicular precipitate of a douhlc componnd. Cold -Trichloride . . Golden-yellow crystalline precipitate of a donble compound. Platinum :-Dichloride Pale-yellow slightly crystalline precipitate of a double compouod. These are with few exceptions the reactions of a solution of potassa. It is scarcely necessary to add that the hydrate of the diphosphonium expels even at the common temperature ammonia phenylamine triethylphosphine and a considerable number of other amines and phosphines from their saline combinations.The free base exhibits the deportment of caustic potassa towards iodine and sulphur. It dissolves c~ystals of iodine with facility; the colourless solution is neutral and yields on evaporation a syrup-like half-crystalline mass easily recognized as a mixture of the di-iodide with the di-iodate. Treatment with alcohol separates the crystals of the more difficultly soluble iodide from the gummy iodate. On adding concentrated hydrochloric acid to the liquid obtained by dissolving iodine in the free base a dark-coloured substance (iodine or a periodide) is separated ; after a few seconds however the liquid is decolorized and solidifies to a mass of beau- tiful lemon-yellow crystals. The diphosphonium-salts are thus seen to exhibit phenomena exactly similar to those which mere observed by Weltzien in the case of the compounds of tetra-methyl- and tetrethyl-ammonium.I hope to find an opportunity of returning to a inore minute examination of the yellow com- pound which by recrystallization from boiling alcohol may be obtained in splendid needles and which will probably be found to be a compound of the di-iodide with chloride of iodine. For the present I may remark that similar compounds are formed by all the bases of the type ammonium and diammonium which I have examined provided they belong to that class in which the sub- stitution is complete. A variety of monophosphonium- and mon- arsonium-salts and lastly of compounds of phosphammoniums and phospharsoniums submitted to the same process have furnished perfectly similar results.Hydrochloric acid occasionally produces crystalline precipitates in thc concentrated solutions of the iodates even of‘ bases of incomplete substitution ;these precipitates dis- appear however on addition of water or on gently warming and are essentially different from the compounds previously mentioned. X.u@hur dissolves in a Concentrated solution of the dihydrate Ensrow OF THE PHOSPHORUS BASES. although with difficulty to a yellow liquid which precipitates the black sulphide from lead-solutions and is decomposed by acids with separation of sulphur and evolution of siilphuretted h-j-drogen. Phosphorus is not attacked by the solution of the dioxide not a trace of phosphoretted hydrogen being evolved even by protractcd cbullition.Disu@hhydrate,-The solution of the base saturated with hydro- sulphuric acid when allowed to remain for some time over sul- phuric acid in vacuo dries up to a gummy mass which exhibits as little inclination to crystallize as the dihydrate itself. When evaporated on the water-bath in contact with the air the disulph- hydrate is decomposed the sulphur being oxidized ;ultimately an imperfect crystallization of the sulphate remains behind. DichZoride.-This salt is easily obtained by treating the dibro- mide or the di-iodide with chloride of silver and also by saturating the free base with hydrochloric acid; it is extremely soluble in water and in alcohol insoluble in ether.The concentrated solu- tion solidifies over sulphuric acid into a mass of large and highly deliquescent crystalline plates of a pearly lustre which may be exposed to a very high temperature (290’ to 300O) without the slightest alteration. The salt is precipitated unchanged from its aqueous solution br potassa; it contains-The dicliloride forms vith metallic chlorides numerous we3 crystallized double compounds some of which will be more par- ticularly described here after The dichloride of the ethylene-diphosphonium is likewise pro- duced by the action of monochlorinated chloride of ethyl prepared in accordance with Regnault’s indications by the action of chlorine upon chloride of ethyl. The chlorinated compound acts but slowly upon triethylphosphine at 100’.By digesting for twenty-four hours at 1ZOO a considerable proportion solidified to a white fibrous crystalline mass which proved to be exclusively the dichloride of the diphosphoniurri. It was identified by con-version into the characteristic platinum-salt and subsequently into the iodide both of which were analysed. Di-iodide.-This salt is perhaps the most characteristic of the diphosphonium-compounds. Cryst allizing with peculiar readiness -being easily soluble in hot but sparingly soluble in cold water,- slightly soluble also in alcohol and insoluble in ether,-it possesses all the properties which can facilitate the preparation of a pure and definite substance. It has therefore for the most part served its a starting-point in the preparation of the diph osphonium- compounds.I have already remarked that in the preparation of the mona- A. w.HOFMANN’S CONTRIRUTIONS TO THE tomic bromide the famation of the dibromide can scarcely ever be entirely Trevented. The mcther-irqtxors remaining after lzumerous preparations of the monatomic bromize were therefore crzited and treated with oxide ol” silver vhereby a caustic liquid vtas obtained containing the hydrate of the diphosphoxGum con- taminated with the hydrate of the oxethylated monophcsphonium arising from the decomposition of the broraethylated ccmpound . These hydrates were converted by saturation with hydliodic acid into the corresponding iodides the separation of which presented no further difficulty inasmuch as the iodide of the oxethylated mormophosphonium is extremely soluble in water and in alcohol.The sparingly soluble di-iodide was easily obtained in a state of perfect purity by several crystallizations. The crystals are anhydrous. Any hygroscopic moisture that may adhere to them is most conveniently removed by drying them over sulphuric acid since the salt begins to turn slightly brown at 1000. Analysis proves this iodide to be represented by the formula,- The di-iodide crystallizes from boiling water in needle-shapcd crystals which often attain a considerable size. Quin-tirmo Sella has communicated to me the following results which he has obtained on examining these crystals :-‘‘ System trimetric :-Fig. 41. iib 001 101 = 450 9’ 100 110 = 60’ x8’ Itc’orrnsobserved :-ioi lo/ Forms observed :-Combinations observed :-1 10 10 1 (Figs.42 43). 11 0 101 with other faces too much rounded for their correct determination (Fig. 44). HISTORY OF THE PHOSPHORUS BASES. Fig. 4+2. Fig. 43. Fig. 4%. Cleavages 1 10 und 10 1 distinct and easily obtained. The crystals are long needles ; the faces 110 are often but little develcped (Fig. 43) ; they hax then a monoci-inic aspect; but the measurement of the angles 1lo 10 1 and T P 0 'I0 1 has fur-nished nearly the same result ; and moreover on examining the crystals with the polarizing microscope the line [O 101 is found to be Dearly one of the axis of elasticity. The angle 10 1 10 1is so near to goo that there might appear some reason for regarding the crystals as dimehie hemi5edrals.I am not however of this opinion for I have observed only two cleavages 110 710 instead of the four corresponding to the dimetric system ; moreover the angle 1 0 1 10 1has always been found a little greater than 90". The needles when small are transparent ; the larger ones Ere rather milky and hollow inside. The lustre of the faces 10 1 is slightly nacreous that of the faces 1 10 is vitreous." The di-iodide as already observed is very much more soluble in boiling water than in cold water. 100 parts of boiling water dissolve 458.3 parts of the salt of which only 3.08 parts remain in solution at l2O. A remarkable character of the salt is its insolu- bjlitity in moderately concentrated solution of potassa ; the dilute solution.mixed with potassa immediately yields a crystalline preci- pitate; the same property is exhibited as is well known by the iodides of tetrethylammonium and of the other ammonium-and A. W. HOFMANN’S CONTRIBUTIONS TO TIIE yhosphonium-metals. The solution of the di-iodide like those of the diphosphonium-salts in general is perfectly neutral ;it is colourless wlien first prepared but on exposure to light soon acquires a tint of yellow and finally turns brown at the same time depositing a reddish compound doubtless analogous to the periodides which as I observed somc time ago are formed under similar circumstances from the iodides of tetramethyl- and tetrethyl- ammonium and which have since been so successfully studied by Weltzien.This red compound is immediately precipitated on adding a solution of iodine to the colourless solution. The di- iodide like most diphosphonium ~compounds exhibits great sta-bility It melts without the slightest decomposition at 231° and solidifies wit,h crystalline structure a few degrees lower. When more strongly heated over an open flame it is decomposed with formation of a red-bro~n substance which I have not examined On distilling the di-iodide with excess of caustic baryta in an atmosphere of hydrogen triethylphospliine passes over no gaseous product is formed in this reaction. Together with iodide of barium which remains behind and triethylphosphine which distils over probably oxide of ethylene is formed in this reaction.I should however state that I have not succeeded experi-mentally in tracing the formation of the oxide of ethylene. An attempt to decompose the solution of the di-iodide with sodium-amalgam was unsuccessful ;the salt which is likewise but sparingly soluble in solution of soda immediately separated out and no appearances were observed which might have indicated the formation of the ammonium-amalgam. It is worthy of remark that no substituted ammonium-amalgam has yet been produced. The di-iodide forms with various metallic salts crystalline double compounds among which I have more particularly examined the zinc-salt ;its analysis will be given further on. Di$aoride.-The solution of the hydrate neutralized with hydro- fluoric acid and dried over sdphuric acid leaves a colourless transparent syrup which does not crystallize even after standing for a considtrable length of time in air or in VUCUO.The fluorine- compound like the other diphosphonium-salts is soluble in alcohol but insoluble in ether. 8ihh-.uoride.-The solution neutralized with hydrofluosilicic acid likewise failed to yield crystals by evaporation. Dicyanide.-The solution of the hydrate mixed with excess of hydrocyanic acid retains its alkaline reaction ; when evaporated on the water-bath it gives off every trace of hydrocyanic acid. On digesting a solution of the di-iodide with excess of cyanide of HISTOBY OF THE PHOSPHORUS BASES. silver a double compound dissolves which crystallizes in splendid needles but is likewise decomposed by evaporation with evolution of hydrocyanic acid and separation of cyanide of silver.I)isu~hocyanate.-?~hen a solution of the di-iodide is boiled with excess of recently precipitated sulphocpanate of silver a solution of the disulphocyanate is obtained perfectly free from silver and solidifying by evaporation on the water-bath into a crystalline mass. The salt dissolves readily in water and in alcohol and is precipitated therefrom by ether. The aqueous solution is likewise precipitated by potassa the oily draps thus separated gradii ally solidifying into crystalline rosettes. Dinitrate.-This salt prepared by saturating the base with nitric acid forms laminar crystals permanent in the air extremely soluble in water less soluble in alcohol arid precipitated from the alcoholic solution by ether as an oil which gradually solidifies.The solution forms with mercuric chloride a precipitate which crystallizes in needles. Dipewhlornte.-This salt is perhaps the most beautiful of the diphosphonium-compounds. On mixing moderately concentrated solutions of the hydrate and perchloric acid the liquid is soon traversed by delictkte crystalline needles often an inch long. They may be recrystallized from boiling water and dried at looo without decomposition. At a higher temperature they are decomposed with slight detonation. The analysis of the perchlorate in which the diphosphonium was weighed in the form of the nearly insoluble platinum-salt led to the formula :-Di-iodate.-The base neutralized with iodic acid and evaporated over sulphuric acid yields an extremely deliquescent syrup which crystallizes but gradually.Solution of potassa separates the hydrate from the concentrated solution in oily drops sparingly soluble crystalline iodate of potassium being at the same time precipitated. The solution mixed with hydrochloric acid yields the lemon-yellcw crystalline compound already mentioned. Carbonate.-The solution of the oxide remains alkaline even after saturation with carbonic acid; on evaporation it leaves a mass having a slightly crystalline structure. Su@hate.-Radio -crystalline extremely deliquescent salt. Repeated attempts to produce dipfiosphonium-alums by mixing the solution with the sulphates of aluminium and chromium were unsuccessful.Chromate.-The solution of the base neutralized with pure chromic acid deposits when exposed to an atmosphere dried by sulphuric acid extremely soluble needles arranged in stellated 100 A. W. KOFMANN'Y CONTRIBUTIONS TO THE groups. With excess of chromic acid nothing but an uncrystal- lizable syrup is obtained. 0xaZnte.-Both the acid and the neutral solution of the base in oxalic acid dries up to a slightly crystalline mass. Phosphate. -Tli~ di-iodide boiled with excess of phosphate of silver yields a neutral solution of the phosphate of the diphos- phonium which remains as a slightly crystalline mass when the solution Is evaporated. Crystallization is not promoted by addition either of free phosphoric acid or of the hydrate.Tartrate.-Extremely soluble ; difficult to crystallize. Dipiwate.-Tlie aqueous solution of picric acid added to a moderately concentrated solution of the hydrate instantly pro- duces a yellow crystalline precipitate which separates from the boiling allraline solution in long needles. The di~)hosphonium-s~lts form a long series of double com-pounds most of which crystallize splendidly. Platinum-salt.-The solution of the dichloride even when extremely dilute yields with dichloride of platinum a pale-yellow precipitate which appears amorphous to ordinary observation but when examined under a microscope of rather high power resolves itself into small prisms. This salt is nearly insoluble in cold and even in boiling water so that as already observed the diphospho- nium may be quantitatively estimated in this form.The precipi- tate dissolves though with difhulty in concentrated hydrochloric acid and crystallizes from the solution by slow cooling in small but well-defined crystals of a bright orange red colour. Quintino Sella has examined thcse crystals and obtained the following results :-''System monoclinic E-100 001 = 82'36' Forms observed 100 010 0Ul (Fig. 45). Fig. 45. Fig. 46. Combinations observed :-100 010 001 (Fig46). HISTORY OF THE PHOSPHORUS BASES. Cleavages 1 0 0 0 1 0 0 0 1 distinct and easily obtained more especially 0 10. The crystals are elongated in the direction of the axis of symmetry and often hallowed out for a great part of their length when rather thick that is to say when their sides attain the width of half a millimetre.The hollow has the form of a pyramid having its base on the face 0 10 and its apex towards the centre of the crystal. The face 0 10 is often reduced to a very narrow rectan- gular rim. The opposite apex of the crystal is irregular as if it had adhered to the side of the vessel. The face 0 0 1is in general rather more developed than 1Q 0. The crystals are optically negative. The plane of the optical axes is parallel to the line of symmetry [O 101 ; the principal medium line is perpendicular to the latter and forms an angle of about 30’ with a liue normal on face 001. In fact a plate parallel to 0 1 0 stops the passage of a ray of polarized light in that direction.Moreover rings are observed through the faces 00 1 and in a plane parallel to the line of symmetry 0 10 and rather incline6 towards a line normal on each Pace. The angle of the optical axis seen in this manner through the faces 00 1 appears to be very nearly 110’. The crystals have a very fine orange-colour and a vitreous lustre.” This platinum salt by numerous analyses was found to COD-tain :-Palladium-salt. -A dilute solution of the dichloride is not precipitated by chloride of palladium. On concentrating the mixture and allowing it to cool slowly reddish-yellow prisms make their appearance by rapid evaporation a brick-red crystalline powder is obtained. Alcohol added to the aqueous solution of the two salts throws down the double salt as a chocolate-coloured crystalline magma composed of small interlaced needles.I have not analysed this compound. Gold-salt.-Beautiful golden-yellow needles difficultly soluble in cold easily soluble in boiling water and containing C,,H3,P2Au,C1 = 1(C2H4)”(c2H5)3pTC12 2Au Cl,. L (C2H5)3Pd Mercury-salt.-Delicate crystalline needles or laminae sparingly soluble in water aud in alcohol obtained by mixing the chloride of the diphosphonium with mercuric chioride. Analysis led to the formula 102 A. w. ROFNANN’S CONTRIBUTIONS TO THE Tin-salt. -This salt which is prepared like the mercury-corn- pound crystallizes from water in large well-formed prismatic crystals. According to some determinations which however gave only approximate results the tin-salt appears to have the compo- sition Di-iodide and Iodide ofZinc.-On mixing the ttro solutions a crystalline precipitate is obtained which separates in long needles when recrystallized from boiling water.The salt which is apt to assume a yellowish coloration contains Dibromide and Bromide of Siluer.-I have mentioned this salt already when describing the preparation of the hydrate from the dibrornide. Then oxide of silver which should not be mixed with too much water is added in small portions to a boiling con-centratcd solution of the dibromide in alcohol as long as it dissolves the filtered solution deposits on cooling white crystals which contain (C T€ ’ PI’’ Br2 AgBr. C,4H3,P,AgBr = [(C2H,)” (c2H5{3p_/ 2 53 The salt crystallizcs but not readily from boiling alcohol.It is immediately decomposed by water bromide of silver being separated and the bromide of the diphosphoniurn passing into the solution. In describing the general character of the action of dibromide of ethylene upon triethylphosphine I have mentioned that in addition to the monatomic and diatomic bromides which are the principal products of the reaction secondary compounds may be formed but always in comparatively small quantities. The mother-liquors generally contain oxide of triethylphosphine formed by the action of the atmosphere ; they contain moreover bromide of triethylphosphonium if the dibromide had not been carefully deprived of hydrohromic acid. The bromide of triethylphos-plonium however under certain conditions arises from the decomposition of dibromide of ethylene into hydrobromic acid and bromide of vinyl the latter producing in this case the bromide of vinyl-triethylphosphonium.I had an opportunity of establishing this fact experimentally when preparing a considerable quantity of the dibromide of the diphosphonium. The phosphcrus-base having been employed in excess in this operation not a trace of the bromethylated rnonophosphonium had been formed its HISTORY OF THE PHOSPHORUS BASES. 103 absence was carefully proved by a special experiment. The bromides were then transformed into chlorides and the latter precipitated by dichloride of platinum ; the raother-liquor filtered off from the copious precipitate of the diphosptnonium-salt was considerably evaporated when on cooling well-formed octohedra were deposited which on analysis were found to contain i(C2HJ (C,H,),P] C1 PtCI2* The formation of the vinyl-compound under these circumstances is easily explained The amount of vinyl-compound produced is but very small in proportion to that of the other salts which are formed in the mutual action between triethylphosphine and dibromide of ethy-lene.OF HEATUPON THE HYDRATE ACTION OF THE D~PHOSPHONIUM. The hydrate when submitted to the action of heat undergoes a series of remarkable changes which I have studied with lively interest. The decomposition commences at 160”; on raising the temperature gradually to 250° the whole of the hydrate passes over in the form of liquid and gaseous products.The liquid product consists of triethylphosphine and oxide of trietliylphos-phine ; the gas contains a considerable proportion of ethylene which is readily characterized by its deportment with bromine. This transformation may be represented by the following equa- tion The study of the changes however through which the hydrate runs before it is broken up shows unmistalteably that this equation can represent but one phase even of the final trans- formation of the diphosphonium-compound. The study of the intermediate changes presents unusual difficulties and I confess at once that I have failed to solve the problem to my entire satisfaction. The experiments carried out with the view of disentangling the intricacies of these reactions will perhaps be better understood if I commence by setting forth the ideas which I have ultimately formed of these metamorphoses and then describe the experiments on which they are founded.Under the influence of heat the hydrate of the diphosphonium undergoes two principal transformations which are accomplished 18% A. fv HOFNANN’S CONTRIRUTlONS TO THE side by side. A portion of this compound gives rise to the €ormation of oxide of triethylphosphine and hydrate of tetrethyl-phosphonium the latter splitting ultimately into oxide of triethylphosphine avid hydride of ethyl while a second portion is resolved into triethylphosphine and hy-drate of oxethyl-triethylphosphonium The latter may undergo at a high temperature a further trans-formation separating partially at least into water and hydrate of vinyl-triethyJphosphonlum the vinyl-compound yielding in the last stage of the reaction oxide of triethylphosphine and ethylene The separation of triethylphosphine and its oxide by the action of heat upon the hydrated diphosphonium requires no special experimental demonstration.To individualize the other compounds the following experiments mere made :-A con-siderable quantity of the dihydrate \+as evaporated in a retort in an atmosphere of hydrogen. As soon as the phosphorus-base began to distil freely-at about 190°-the operation was inter- rupted and the residuary alkaline liquid saturated with hydro- chloric acid and precipitated with dichloride of platinum.A dingy yellow amorphous precipitate was thrown down insoluble in cold water; and the mother-liquor on evaporation furnished a mass of deep orange-red octohedra which were transformed into the corresponding iodine-compound. The salt thus obtaincd proved unmistakeably a mixture of two compounds of different solubility. The less soluble mas obtained in beautiful crystals exhibiting all the characters of iodide of tetrethylphosphonium. The formation of a tetrethylphosphonium compound in this reaction was identified by the analysis of the iodide the platinum. salt and the gold-salt. The result of ar,alysis was most satisfactorily confirmed by the crystallographical examination of the salts under consideration.Q. Sella hats compared the crystals of the iodide above men- IIISTOICY OF TBE PIiOSPIIORUS BASES. tioned with crystals of iodide of tetrethylphosphonium obtained in the usual way. I have appended at the conclusion of this paper the elaborate investigation of this beautiful salt with which my friend has furnished me. Far less conclusive is the experimental evidence which I was enabled to collect in support of the opinion that the hydrate of tetrethylphosphollium formed by the action of heat on the hydrated diphosphonium is accompanied by the oxethylated triethylphosphonium compound. The principal argument in favour of this view is the abundant evolution of triethylphosphine which cannot be understood unless we assume the simultaneous formation of the oxethylated or of the vinyl-compound.I have failed in my endeavours to prepare the more soluble iodide which accompanies the tetrethylphosphonium-compound in a state of purity. Nor was the attempt to separate the two compounds in the form of platinum-salts rewarded by better success. Both platinum-salts crystallize in octohedra which differ but slightly in solubility. The experimental numbers obtained in the analysis of thcse octohedra characterize a mechanical mixture of the two platinum- salts. The action of heat upon the hydrate of the diphosphonium induces yet another transformation to which I have already allirded ,when mentioning the dingy yellow insoluble precipitate which is formed on addition of dichloride of platinum to the product of the action of heat upon the hydrate neutralized with hydrochloric acid.The follow i 11g paragraph cont ain s the fragmentary inform at ion which I have collected in studying these changes. PARADI PH0SPH0NIUM -C0A1 POUNDS. The basic compound which yields the amorphous yelIow platinum-salt repeatedly mentioned is a transient product of the action of heat on the hydrated diphosphoniarn. If during distil- lation the alkaline residue in the retort be tested from time+to time with dichloride of platinum a point is soon reached when instead of the slightly crystalline precipitate perfectly insoluble in dilute hydrochloric acid which appears at the commencement of the operation an amorphous generally dingy yellow precipitate is obtained immediately dissolving on addition of a few drops of (tilute hydrochloric acid.If the distillation be now interrupted and the residue neutralized with hydrochloric acid and mixed with a few drops of dichloride of platinum a discoloured precipitate is thrown down the filtrate from which on addition of a further quantity of platinum-solution yields the amorphous salt of a light yellow colour and in a state of purity. This salt exhibits no VOL xzv. 1 d. W. HOFJIANN'S CONTXIBUTIOXS TO TIIE trace of crystalline structure even when examined under the most powerful microscope in the perfectly dry state it is remarkably electrical flying about in all directions during trituration. The same sribst ance is obtained when tlie hydrated oxethyl- trietliylphosl~~ionium is submitted to tBc action of heat.By interrupting the process at a convenient time and adding dichloride of platinum to the neutralized residue phenomena identical with those just mentioned are observed. The compound which produces the amorphous yellow precipitate was lastly obtained under the following circumstances. While I was engaged with the study of the vinyl-compounds the examination of which is dcscribed in one of' the previous paragraphs of this paper the idea suggested itself that the bromide of ~inyl-tr~ethylpiiosp?~o~i~i~ might also be formed by the action of bromide of vinyl (C,H,Br) on triethylphosphine In performing the experiment I had an opportunity of observing the sluggishaess of action of this bromide often previously noticed in experimenting in the ammonium-series.When gaseous bromide of vinyl is passed through triethplphosphine not a trace of it i5 fixed by the p!iosp?iorus-base. Trietliylphosphine may be distilled in an atmosphere of the bromine-compound without undergoing any alteration. Bromide of vinyl freed from every trace of adhering dibromide of ethylene by repeated distillation at a low temperature and subsequelit washing with lukewarm water was therefore enclosed together with triethylphospliine in a strong glass tube. No change wa:j perceptible after two days' digestioa at 100" ;and it was only on the third day that a thin layer of viscid matter began to separate at the bottom of the tube. The digestion was then continued at a higher temperature; and after the mixture had been exposed for three days longer to a tempera-ture varying from 160" to 180" about half the fluid was found to be converted into a solid mass while a limpid liquid floated on the top.On opening the tube cooling it well at the time the liquid egervesced strongly and a gas escaped which burned with a green-edged flame and appeared to consist partly at all events of the vapour of unaltered bromide of vinyl. In subsequent repetitions of the experiment it frequently happened that the tubes were shattered by the sudden expansion of the compressed gas hence probably permanent gases are formed in the reaction. The liquid decanted from the solid proved to be a mixture of undecomposed bromide of vinyl with free phospliorus-base ; the solid niass was found to consist of several bodies.On dissolving it in water a rather small quantity of a sparingly soluble beautifully crystalline nacreous salt separated out the composition of which is at present undetermined. By treatment of the filtered solution with oxide HISTORY OF THE PEIOSPEIORUS BASES. of silver a strongly alkaline liquid was produced which when neutralized with hydrochloric acid and precipitated with dichloridc of platiuum gave at once the amorphous yellow platinum-salt easily soluble in dilute hydrochloric acid. On aiialysis this salt furnished results which characterize the platinum-compound of ethylene-hexetBy1-diphosphonium Nevertheless the two substances are not identical.In addition to the difference in the physical properties and in the behaviour with dilute hydrochloric acid the two salts exhibit other welI- defined marks of distinction. The crystdline salt is perfectly insoluble in water even when boiling. The amorphous salt dis- solves readily and is depvsited again on cooling in the same amorphous condition. In designating this peculiar molecular variety as paradiphosphonium-compound I simply wish to distin- guish it from the salt of the ordinary diphosphonium without giving any opinion respecting the nature of the difference. The existence of the diphosphonium-compounds in the crystalline and in the amorphous condition reminds us of the beliaviour of some of the native organic bases under the influence of heat.It is well known that several of these substances which are remwkable for their powers of crystallization are rendered perfectly amorphous when heated for some time above their melting-point As might have been expected the paradiphospl~onium-corn- pounds are slowly and gradually reconverted into the ordinary diphosphonium-salts.* The hydrated paradiphoaplionium when separated from the platinum-compound by successive treatment with sulphuretted hydrogen arid oxide of silver yields with hydriodic acid a gimmy mass which only gradually assumes the crystalline form. By a considerable number of recrystallizations the characteristic di-iodide was ultimately obtained with all its properties ;when con- verted by treatment with chloride of sil vert into the dichloride and precipitated by dichloride of platinum it immediately yielded the well known crystalline precipitate so frequently mentioned in this paper.Both salts the iodide and the platinum salt were identified by analysis. The transition of a diphosphonium-compound from the crystal- line to the amorphous and from the amorphous to the crystalline condition appears intelligible enought. The transformation of the oxethylated monophosphoniurn however into a diphospho-nium-compound and the formation of the latter by the action of *In sereral expeiiments the reaction between bromide of vinyl and triethylphos- phine gave rise to the formation of a mixture of the amorphous and crystalline diphosphonium-compounds. tThe diphoaphoninm-salt which is formed by the action of sulphocyanate of ethylene upon triethglphospphine (Chem.Soc. Qu. J. vol. xiii p. 320,) in the first place likewise yields the amorphous platinum-salt when precipitated by dichloride of platinurn. I2 108 A. w. HOFMANN’S CONTRIBUTIORSTO THE bromide of vinyl upon triethylphosphine claims our attention for a moment. The conversion of the hydrate of o~etli~l-triethylphosphoniu~* into the hydrated diphosphonium is readily understood if me remember that two molecules of the former coiitain the elements of one molecule of the lattex and of one molecule of ethylene-alcohol I am unable to say whether the group C2HG02 actually separates as ethylene-alcohol or which is more probable in the form of water and oxide of ethylene or even of aldehyde.Material and patience began to fail when I had reached this point and I must reserve the decision of this question to later experimentsf; The same remark applies to the final elucidation of the re-action between triethplphosphine and bromide of vinyl which as I have pointed out likewise gives rise to the formation of diphos-phonium-compounds. Two molecules of trieth ylphosphine and two molecules of bromide of vinyl contain the elements of one molecule of dibromide of the ethylene-diphosphonium and one molecule of acetylene and experiment proves that a considerable amount of permanent gas is generated in this reaction; but there are other products formed and it; would be idle to dwell any longer on the interpre- tation of these unfinished observations.In conclusion I append Q. Sella’s crystallographical examina- tion of the iodide of tetrethglphosphonium to which I have * I need scarcely mention that the purity of the compound used in my experiments had been established by a Bpecial analysis. When prepared from imperfectly puri- fied bromethylated bromide the oxethylated base is apt to contain minute quantities of the hydrate of the diphospbonium. The convertibility of the oxethylated triethylphosphonium-salts into diatomic compounds has induced me to try whether the action of triethylphosphine upon them woiild accomplish this transformation ; [(C2H50) (c2H5hp1H) 0 + (C,H5),p = [(c2H4)” (C2H5)G p!21” 0 H2 1 2. Rut eren when heated up to 150”,the two bodies remain unaltered; nor is there any action when the oxide is replaced by the bromide of oxethyl-triethylphoapbo-nium.HISTORY OF THE PHOSPHORUS BASES alluded in the latter portion of this paper and also the results obtained by him in measuring the corresponding platinum-salt. Crystalline form of Iodide of Tetrethylphosphonium. Fig. 47. System rhornbohedric :-11I 100 = 59" 3%. Forms observed :-111 ioi 100 110 210 31'1 (Fig 47). Forms observed :-a' d' P b' b2 e3. Fig. 48. Fig. 50. Fig 49. OM-Ooi ? Combinations observed :-31 1; lo@,lOi (Fig. 48). 311 111 100 (Fig. 49). 3 1i 11 1 10i; 100 (Fig. 50). 311 110 100; lor 210 {Figs 51 and 52). 311 100 110; ioi 210 111. The crystals prepzred by treating triettiylphosphine with iodide of ethyl exhibit the forms Figs.51 and 52. Fig. 51. Pig. 52. The crystals obtained by submitting the hydrated diphos- phonium to the action of heat and neutralizing the alkaline residuary product with hydriodic acid have the form Fig. 48 when rather large and slightly yellow and the forms Figs. 49 and 50 when minute and perfectly white. The crystals of the form Fig. 50 are most frequent ; they seem to have adhered to the vessel with one of the larger faces of the prism ioi. Crystals distinct. Lustre on the faces except 11 1 very great. Crystals optically positive. The indices of refraction are for the ordinary ray w = 1.660 for the extraordinary ray e = 1.668. The crystals of iodide of tetrethylphosphonium are isomor-phous with those of iodide of silver.In the latter substance 111 100 = 58’ 27’ instead of 59” 32’,found in the tetrethylphos- phonium-salt. Both salts have the same hexagonal habitus and both are optically positive.” Crystallineform of the Platinum Salt of Tetrethylphosphonium. Fig. 53. c‘ System monometric :- Forms observcd :- 1 flI .. 100 111 (Fig. 53). i,i d The faces of the cube 100 are very brilliant; those of the octohedron 111are often hollow. No influence on polarized light. Colour orange-red.”

ISSN:1743-6893    

DOI:10.1039/QJ8621400073

出版商:RSC    

年代:1862

数据来源: RSC

摘要:

111 IX.-On the Ice foutzd uizder the surface of the t;f/aterin Rivers called Ground Ice. By RICHARD ADIE. Liverpool. THEice found in the bed of a river or running stream under the surface of the water is a subject which has engaged the attention of men of science to endeavour to account for its occur- rence in an apparently unnatural position while it has also forced itself on the attention of practical men on account of the mischief vhich an accidental obstruction such as a branch of a tree lodged in the bed of a mill-course has been foGncl to occasion when the mter is charged with ice particles. I believe that I was among the first to state that ground-ice is formed in the coldest part of a stream and that the small crystals immediately after they are formed are carried along by the current submerged and entangled by plants or other obstriictions in the bed of the stream suitable for their detention.In the recent frost of December and January 1860-62 I searched for ground-ice where in past years I had found it. Yet though this frost was the most severe that has visited us during the sixty years of the century I found ground-ice only in one locality,-a shaded place where I was induced to search for it from seeing bundles of ice-crystals floating down the stream; for I had beford observed that where ground-ice exists some of it is constantly breaking off from the moorings. In this imtance the ice sur- rounded a stone covered over by the water of a rivulet which leaves the Marquis of Abercorn’s grounds at Duddingston near Edin- burgh.The other streams which I examined in the neighbourhood of Edinburgh shewed no floating crystals or other indications of the presence of ground-ice; they appeared to be well supplied with water which coming from underneath a covering of snow was unfavourable for showing this kind of ice. In the frosts of 1854 and of 1855 I found ground-ice in a number of rivers. These frosts differed from the recent om by penetrating into the ground to a greater extent. In 1854 the 112 ADIE ON GROUND ICE. frost entcred into the ground to the depth of 113 il?ches and thnt of 1855 to 13; inches. In 181iT)-l tlie earth had merely a crust of frozen soil under the snow,* 'l'he general calmness of the weather must lilrewisc have had influcncc; for in an espsed district in the neighbourliood of Liverpool I have repeatedly found quantities of ground-ice after two days' moderate frost accompanied by a dry brisk wind.Those who have examined ground-ice appear to think that the ?water has frozen in the bed of the river the current preventing it from freezing in its natural place-the surface. The appearance of tlie masses formed do not favour this view for many shady positions in streams are noted for exhibiting collections of ice that could never have frozen there. To ascertain the nature of ice when formed under water on the sides of a containing vessel I produced it rapidly by a freezing mixture when the ice assumed a very hard form A small stream about twelve miles from Liverpool where it joins the river Alt is extremely favourable for showing the phe- nomena of ground-ice in an open exposed district.I first saw it there in December 1846; and as I have since often examined the ice iu the beds of streams I wish to mention that the circumstance which appears to me most favourable for its formation is wind accompanying the frost. On 13th December 1846 the ground- ice was plentiful; my note at the time states that the frost had not been severe but the air had been very dry with a brisk wind. Ground-ice is capricious both in its time and place of settlement. On 3rd January 1854 I saw it in very large quantities in the bed of the Eden a little above Carlisle. In February 1855 after a frost which had gone deeper down in the grounci than the one of the previous year I searched the same part of the Eden without seeing any; there were a sufficient number of loose ice crystals floating down the stream to rcnder it probable that ground-ice existed higher up.On the same day I had seen ground-ice in th'e Ribble above Preston but none in the Lune above Lancaster. After I had become satisfied that the position of ground-ice is * Since the above was written the writer has been informed by a friend residing fifteen miles west of Edinburgh where the snow was not so deep that the frost in that locality penetrated the ground to the depth of an inch; and in a very few places where the ground had been denuded of snow by the wind the earth was frozen to the depth of thirteen inches.ADIE ON GROUND ICE. one of lodgment merely I have been in the habit of searching for it where the streams pass under stone arches and places most unfavourable to freezing and in these localities I have several times found it. The masses I have referred to as seen in the Eden in 1854 must have been lodged there for thy contained throughout their substance a few water-worn pebbles and they were all inclined towards the current from whence they were receiving continual supplies. I could not get at the collections of ice to measure them as they were all under the surface in a deep- flowing part of the stream; but one rose so near the surface as to give a ripple to the current and appeared to be from 4 to 6 feet high.Note on Mr. Adie's Paper On Ground Ice." By E. FRANKLAND, F. R. S. THE formation of ground-ice has excited considerable interest amongst the observers of natural phenomena and various sugges- tions have been made to account for its production. One of the most ingenious of these assumes that in rapidly-flowing streams the eddies and currents cause such a constant intermingling of the upper and lower mater-strata as to render the whole mass of the stream of one uniform temperature. When such a stream becomes cooled down to the freezing-point the usual surface-layer of cold water below 39.5' F. cannot of course be formed. The rocks and other solid bodies in the bed of the stream continue however to radiate heat through the water into the atmosphere and thus become reduced in temperature below the freezing point ; the necessary consequence of such a state of things being the forma- tion and gradual accumulation of ice around such solid bodies.The latter part of this hypothesis appears to be untenable inas- much as water is absolutely intranscalent to rays of' obscure heat consequently the passage of such rays from the bed of the stream through a stratum of water is absolutely impossible. It appears to me that the formation of ground-ice which is well known to take place only in rapidly-flowing streams depends upon the fact that ice like other crystalline bodies deposits itself more readily upon rough surfaces,--freezes in fact at a somewhat higher tem- perature when in contact with such surfaces than within the masF 114 DR.T€IUDICEIU&1 ON THE of liquid itself. Hence when a rippling stream is cooled to the rreezing point ice-crystals attach themselves to the pebbles and other objects in the bed of the river these crystals forming equally inviting nuclei for the further deposition of larger quantities of' ... ground-ice. The tendency of ground-ice to form in shady places as mentioned by Mr. Adie is an interesting observation which may probably find an explanation in the circumstance that water and ice although perfectly unable to transmit obscure rays of heat are yet to a certain extent transcalent to luminous heat. Tyndall has shown that certain interior portions of a block of ice may be melted by lumi- nous hcat which has already passed through a considerable thick- ness of ice; and it is well known that if a mass of ice containing an embedded pebble be exposed to the solar rays the ice around the pebble soon becomes melted.Any exposure therefore of ground-ice and its supernatant water to solar radiation would have the effect of warming the non-icy nuclei; thus renielting during the day a portion at least of the ground-ice which had been formed during the previous night consequeiitly such an exposure must be regarded as presenting an obstacle to the formation of this kind of ice although it is well known to favour the pro- duction of the ordinary surface ice.

ISSN:1743-6893    

DOI:10.1039/QJ8621400111

出版商:RSC    

年代:1862

数据来源: RSC

摘要:

DR. T€IUDICEIU&1 ON THE 114 X.-On the Putrefaction of Rile and the Anatysis and Theory of Gallstones. By DR.THUDICHUM In October 1859 I communicated to the Medical Society of London a Paper in which I described casts of the biliary ducts which I had discovered in the centre of human gallstones. As these casts consisted principally of brown colouring matter of bile or that modification of cholochrorne termed cholophaeine I first studied the chemical nature of that substance in order the better to understand its bearing on the processes in which it played so conspicuous a part. The results of these inquiries I Communicated to the Physiological Section of the British Association for the Advancement of Science at the Oxford Meeting in ISSO and an PUTBEFACTIOX OF BILE.abstract of my communication has appeared in the ‘‘British Medical Journal” for July l4th 1860. I proved that cholochrome is an amido-acid ; that it is decomposed by nitrous acid with evolution of nitrogen and yields a new acid--cholochromic acid,-which is free from nitrogen and in its crystallized state resembles the sub- stance termed by Vircho m ‘‘ hEmatoYdine,” but nevertheless differs from it in many particular properties. I described several other products of decomposition and reactions of cholochrome and among them the most important one viz, that it is precipitated during the putrefaction of bile from the solution in which it was field by the healthy fluid. This led to the re-investigation uf the process of putrefaction of bile which had already been instituted by former observers; and I was not merely enabled to confirm the principal features of the description given by Gorup-B esanez but also to add some new facts explain the origin of some substances discovered by him and construct a theory of this process of decom- position which led me up almost in a straight line to the theory of gallstones.On subjecting large quantities of material to chemical analysis these concretions yielded the same substances as those which made up the deposit of putrid bile with the sole exception of mucus of which little or none could be found in gallstones. Of these researches I gave a short account to the British Medical Association at their Annual Meeting held in 1860 at Torquay.While able to accompany the leading ideas by the exhibition of specimens progressively proving every step of my analyses the limitation of the time imposed upon me by circumstances on that occasion did not permit me to do justice to the subject. I there-fore more fully expounded my ideas before the Medical Society of London in a Paper read before them on October 8th 186Q,and reported in abstract in the rc British Medical Journal” for Octo- ber 13th and the contemporaneous numbers of the other medical periodicals. I then exhibited cholachrome cholic acid and earthy salts as essential constituents of gallstones in man and animals. I characterized the cholesterine in gallstones of man as a secondary ingredient calling for new analyses to prove the freedom from cholic acid of concretions reported to have consisted of pure chole- sterine Having come to the conviction that the binding material of gallstones is cholic and choloidic acid I eliminated as untenable the idea of an inspissation of mucus in the formation of these con-cretions which had hitherto been the groundwork of all speculations upon their origin.116 DR. THUDICIIUM ON THE In the present communication I propose to give a short analysis of my results as a preliminary guide to the reader and then to describe the chemical proceedings which I adopted for the purpose of ascertaining the composition of human and bovine gallstones and of ox-bile Theory of Gallstones In some examinations of human gallstones I had found a resinous biliary matter ; but owing to the small quantity and the refrac- tory nature of the substance and particularly to the difficulty of separating it I had not been able to identify it.The examination of some ox-gallstones afforded an opportunity for settling this point. I extracted a large quantity of cholic and choloidic acid fromethem,-a quantity such as could never be derived from any bile with which the calculi might be supposed to have been soaked at the time they were taken out of the gall-bladder. There could be no doubt that both cholic and choloidic acids had been deposited together with the cholochrome during the pathic process in the living animal. The presence in almost all biliary concretions of some earthy and alkaline salts points in the same direction.They are and were in my analyses either present as phosphates and carbonates of lime and magnesia and could be extracted by hydrochloric acid or they were combined with the colouring matter of bile and with stearic and palmitic acid. In gallstones from man the colouring matter was accompanied by a larger proportion of inorganic salts; but in gallstones of the ox the quantity of cholochrome preponderated to so extraordinary a degree over the earthy matter that it must be assumed to be present in the free state and not as Bramson supposed it to be always viz. combined with lime. Cholochrome cholic and choloidic acids and earthy salts thus present themselves as substances without the concurrence of which the more common forms of gallstones would rarely be formed; they are in other words essential ingredients of gallstones.In man gallstones contain a large amount of cholesterine in most cases but that is a secondary ingredient as the phosphatic crust is of the uric acid or oxalate of lime calculus from the urinary bladder and is mostly crystallized around the other matters forming the nucleus. There are human gallstones which like those from the ox contain 110 cholesterine. Others are said to consist entirely of chole- PUTREFACTION OF BILE. sterine,-a statement which has to be verified by fresh analyses which must prove the absence of cholic and choloidic acid. In gallstones from man stearate and palmitate of lime are mostly present; and it remains to be seen how far those substances can assist in effecting the coricretion of the detached particles of cholo- chrome which 1 now ascribe to the cholic and choloidic acid.Let us therefore dismiss the hypothesis of the inspissated mucus or the inspissated bile which figure in our pathogeny as the mortar which combines the particles of the nucleus mucus is not found in gallstones; and an inspissation in the midst of fluid bile is quite incomprehensible. Moreover even an indubitable inspissation of bile could not lead to an insoluble concretion. We may therefore reject this hypothesis and admit that the binding material of the nucleus of gallstones is cholic mid or choloidic acid or both. The process by which gallstones are formed appears analogous to that which produces that rare description of calculus in the urinary passages,-t!ie phosphatic or fusible calculus.It is a decomposition of the bile akin to putrefaction. The compound amido-acids split up into their constituents under the influence of a cause which remains to be ascertained but is probably a putrid ferment absorbed from the intestinal canal. Under the influence of a little acetic acid formed out of glycocoll and some other new acid produced by the putrefactive change perhaps valerianic acid cholochrome a quantity of cholic acid and a portion of choloidic acid together with some salts and little fat are deposited. This is the process in the ox and sometimes in man. But the bile of man differs in this respect from that of the ox that it contains cholesterine while that of the ox contains at the most only a very small quantity as compared to the other.This cholesterine is dissolved in the taurocholate of soda. But as soon as the acid of this salt is decomposed the cholesterine is set free crystallizes and deposits upon any particle that may happen to be wjthiu easy distance in the manner of all crystals which like to post them- selves upon prominent bodies. Numerous are the modifications which this process may iindergo ; but their discussion must be reserved for future occasions. The presence of chloride of sodium iron copper and other inorganic matters in gallstones has no doubt a significance in each case but a subordinate one. In some gallstones from the ox I have again found a sulphurous compound already observed by Bolle in 1852.W-hen boiled with hydrochloric acid they gave out vapours which IIR TIlUDICHUM ON THE smelt like sulphuretted hydrogen and blackened lead-paper. coilected them in caustic potassa mixed with some solution of arsenious acid. On subsequent acidification a yellow somewhat orange-coloured deposit of a sulphur-compound of arsenic was formed; but after drying it had become brown and hard and on sublimation yielded tersulphide of arsenic besides leaving a quaii- tity of charcoal; thus proving that the gas was a compound of a carbonaceous and a sulphurous body in a volatile form or a mix-ture of two analogous substances. Putrefuction of Bile. Some large bottles full of bile and well stoppered had been allowed to stand for the period of two years and one year respec- tively.The bile had assumed a fecbly acid reaction a bright pork wine colour and had deposited a copious flaky green and brown deposit mixed with white chalk-like particles and greenish crystals. This deposit on analysis was found to cousist of cholochrome cholic acid phosphate of lime and magnesia irr dichroic crystals and mucus. The fluid part of the bile was found to contain prin- cipally choloidate of soda with little clioiate taurine valerianate and acetate of soda and ammonia phosphate of soda but no glyco- coll nor any glycocholic or taurocholic acid. It mas quite clear that the bile had spontaneously undergone a decomposition similar to that which is effected by boiling with acids or alkalies,-a decomposition wliicln in its main features has already been described by Gorup-B esanee Glychocolic and taurochdic acids had split respectively into glycocoll taurine and cholic acid.The cholate probably or some other decomposing substance had yielded valerianic acid which had combined with soda or with ammonia which latter probably originated in the decom- position of glycocoll. This compound being the amido-acid of acetic acid no doubt in this process as in the putrefaction of urine yielded the acetic acid which combined with the necessary amount of soda and precipitated a portion of the cholic acid while the greater portion of this acid remained in solution combined with soda and became further metamorphosed into choloidic acid and perhaps other products of decomposition of an acid nature.The cholochrome had no doubt been precipitated by the new acid before cholic acid as its acid properties are much less pronounced. PCTREFACTION OF BILE. The port wine colour of the fluid was probably due to some rneta- morphosed cholochrome possibly cholochromic acid or a derivate. That cholochrome cholic acid and crystallized phosphates are precipitated in this process had not been observed by Gorup- B e s an e z who had also neither found valerianic acid nor explained the origin of the acetic acid which he undoubtedly discovered.* These observations then and the theory of the process are my own additions to the doctrine. Gorup-Besanez extracted also a mixture of fatty acids from putrid bile among which he believed to have recognized margaric acid.This acid or its fellow stearic acid is a component of the first deposit formed in putrid bile. But like cholesterine in ox-bile this ingredient is too easily lost sight of‘ in consequcnce of the small quantity in which it is present. When Gorup-Besanez allowed bile to decompose at a tempe- rature of from 25O to 30”R1exposed to the free access of the air for a period of three weeks he obtained choloidic acid as the prin- cipal product of decomposition. When however he exposed bile to the air for three months in a cellar at a temperature varying between looand 12’R he found cholic acid instead of choloidic. In both cases the decomposed mass had an offensive ammoniacal smell and a marked alkaline reaction Taking into consideration only one element viz.that of time he concluded that choloidic acid was the forerunner of cholic acid ; that the latter was produced from the former; that the prescnce of cholic acid was evidence of a more advanced stage of decomposition than that of choloidic acid. But he omitted to take into consideration the most important fact -that the specimen of bile which yielded the cholic acid had been subjected to a much lower temperature than the specimens which yielded the choloidic acid and had thus bcen influenced by cir- cumstances which above all others retard the decomposition of animal matters. His assumption therefore while unsupported by any direct proof is opposed by the fact that we know choloidic acid only as a product of decomposition of cliolic acid; that we cannot reproduce cholic from choloidic acid; and further by the results of my own investigations which showed that bile after one year’s and after two years’ decomposition contained principally choloidic acid; a portion of this biliary element only being preci- pitated in the form of cliolic acid.This precipitnte it is but right * Ann. Ch.Pbarm. lix 129. 120 DR. TRUDICRUM ON TIIE to conclude was produced at a time when cholic acid prevailed for had choloidic acid prevailed at the time of the formation of the new acid (acetic valerianic and. others) the deposit must have consisted of choloidic acid or at least contained some clioloidic acid while in fact it contained hardly any or none.No cholic acid remained in solution. On account of these facts I believe that we must reverse the order of succession assigned to those acids by Gorup-Besanez giving to cholic acid priority in time to choloidic acid ultimate supremacy and ascribing to its break-tip into the fatty acids above-mentioned the destruction of the biliary state. Bile decomposed at a moderate temperature during nine months mas found by Gorup-Besanez to exhibit an acid reaction due to the presence of acetic acid in a free state. It consequently had the same reaction as the specimens examined by myself He does not state in what condition the biliary acid was present; which is much to be regretted as free acetic acid could not be present so long as any cholate or choloidate remained in solution the acids of which salts in his analyses he always precipitated by acetic acid.Diagram exhibiting the Decomposition of Bile. First Stage. The bile is neutral or alkaline. Taurocholate of soda yields {Cholate Taurine,of soda. (Cholate of soda. Glycocholate of soda yields ~Glycocoll. Margarate (Palmitate) and stearate of lime Phosphate of lime and magnesia Second Stage. The bile becomes acid by tlie supervention of a new (valerianic 3) acid whose origin is undecided. Cholate of soda deposits cholic acid. Soda-salt of new acid is formed. Cholochrome (Cholophaeic acid) is precipitated aud partly trans -formed into soluble cholochromate (3) (Acetic acid.Glycocoll yields Amlnonia. PUTREFACTIOS OF BILE. Third Stage. The bile continues acid. Cholate of soda is transformed into choloidate. The latter deposits some choloidic acid (?). Choloidate of soda yields fatty acids products of decomposition ; among them probably derived from glycocoll acetic acid in the free (?) state. The alkaline condition during the first stage observed by Gorup- Besanez occurs only when bile putrefies at a high temperature SO that the mucus uiidergocs active decomposition and produces ammoniacal compounds. The bile upon which I operated at low temperatures and with moderate access of air T could not at any time discover to be alkaline. In one case Gorup-Besanez observed the acid reaction to give may to a second alkaline reaction but did not notice any corresponding essential changes.Owing to these uncertainties I have not distinguished as stages the neutral alkaline acid and last alkaline conditions. Gorup-Besanez is of opinion that the decomposition of the primary biliary acids is not effected until an acid reaction of the bile appears; because only at that juncture does acetic acid produce a precipitate of cholic or clioloidic acid. But this negative test appears to me only relative because the acids may be decomposecl and yet acetic acid may produce no immediate precipitate more acetic acid being required to cause a precipitate at the period when the bile is yet neutral or alkaline and when no adventitious acid has yet taken the edge off the alkaline phosphate of soda which is invariably present in bile and though not very evident to test-paper neutralises some acid before an acid reaction can become established.To the naked eye the first stage is characterized by the deposition of white gra- nules partly on the top of the fluid partly at the bottom partly against the walls of the vessel whieh consist of palmitate stearate and phosphate of lime. All the stages no doubt gradually pass into each other; and the above diagram while considered useful for illustration must not be considered as an absolute syllabus of a variable process. Analysis of human gallstones. I must here distinpish between the general analysis of gall. stones by which the essential constituents are found and those special processes which are directed to the isolation of certain less VOL.XIV. K DR. TIIUDICHUM ON TIKE frequent ingredients such as copper manganese sulphides or uric acid. Those human gallstones which consist principally of cholochrome are to be analysed by the process which will be detailed lower down as applicable to gallstones from cattle. For the analysis of the cominon cholesterine concretion from man the following process will be found suitable. The powder of the calculi is gradually thrown into hot benzole contained in a flask placed on a sand-bath. The cholesterine and biliary matters are dissolved while cholochrome earthy phos- phates earthy salts of fatty acids and any other ingredients remain suspended and unchanged.Solution and residue are separated by filtration. The matter on the filter is washed with repeated quantities of benzole lastly with cold alcohol and dried. It then presents itself as a brown powder which is very delicate to the touch imparting an almost velvety feel. Treated on the filter with absolute ether containing little nitric acid it yields fatty acids to the ether which on distillation of the ether from the filtrate are deposited in a granular and crystalline form. If the residue on the filter is next treated with water phosphate and nitrate of lime and magnesia are extracted and remain as phos-phates and carbonates sometimes coloured blue by copper on evaporation of the solution and incineration of the residue. The colouring matter extracted with ether and nitric acid and water is free from fatty matter but retains some earths which can only be obtained by burning the cholochrome or by dissolving it in carbonate of alkali when the earthy and other insoluble inor- ganic and organic matters remain behind.They are then inciner- ated and the ashes added to the earths extracted by aFid and water. The carbonate of lime may be recognized by the effervescence which takes place on dissolving the earthy salts in hydrochloric acid. The subsequent addition of ammonia in excess precipitates the phosphates while the lime which before had been as carbo- nate remains in solution and may be precipitated by phosphate of soda or oxalate of ammonia. From the original benzole solu- tion cholesterine is best obtained by evaporating the solvent and treating the residue with boiling spirit of wine.On cooling the cholesterine which before had been greenish crystallises in the usual glistening white plates while the solution retains the brownish-green coloured biliary matters. On evaporation a small quantity of a mixture of cholesterine and fat is deposited. That PUTRl$FAC'ITON OF BILE and the rest of the alcohol being removed there remains a brown resinous mass insoluble in water soluble in alcohol and soluble in caustic potassa; an excess of caustic ley added to the solution causes the separation of a resinous salt which floats on the top of the caustic fluid. From the solution in potassg it is pre-cipitated by hydrochloric acid It combines with lime and baryta forming insoluble compounds and is therefore choloidic acid though brown and impure and perhaps as suggested by the analysis of ox-gallstones mixed with some cholic acid.It yields a small quantity of matter to boiling water ;but the nature of this extract could not be determined by crystallization as was the case in the analogous extract from ox-gallstoues. Tn his directions for analysing human gallstones Sim on refers hypothetically to the presence of biliary resin without however stating its presence as a positive occurrence or grasping its signi- ficance. In the ordinary analysis of gallstones which began with the extraction of the powder :by means of caustic potassa,--a pro-cess mainly directed to the purification of cholesterine choloidic (and cholic) acid remained with the cholochloine produced from which it could afterwards be scarcely separated.When the ana- lysis of gallstones had however for its principal object the pre- paration of cholophaeine the spirituous mother-liquor of chole-sterine was not thought of sufficient importance to deserve further scrutiny; and even if it had been granted it is possible that the fatty salts dissolved by the boiling spirit (which in the analysis with benzole remain undissolved and are subsequently decomposed with acid and extracted with ether and water) would have made the separation of the choloidic acid a matter of considerable difi- culty. Analysis of ox-gallstones. The gallstones are powdered and boiled with water during three hours.The dark-brown extract is removed by filtration and the residue on the filter washed during three days with boiling water -that is until the filtrate comes away colourless. The powder is then dried in the water-bath. The water-extract is evaporated. It is then boiled for several hours with alcohol of 80" strength which also acquires a dark colour and is separated by filtration. The residue is for several days washed with boiliug alcohol and dried. The primary filtrate is allowed to cool by itself and the DR. THUDlCHUM ON THE washings are evaporated by thcmselves. The alcoholic extract is further analysed as mill be detailed lower down. Thc powder is next mixed with water in a flask and a quantity of hydrochloric acid added.A slight frothing ensues and the smell of sulphuretted hydrogen is at once perceptible ; lead-paper is turned black by the gas. It is therefore necessary to perform the extraction with hydrochloric acid in a gas-evolution bottle with funnel for the addition of the wid and two tubes one for passing a current of air through the acid fluid the other for con-ducting the gases through an alkaline solution of arsenious acid coloured blue by litmus. In my first analysis this alkaline solu- tion was contained in two bottles and as soon as the acid va- pours had coloured the litmus red the first bottle was removed the second bottle put in place of the first and a new bottle in the place of the second.All the sulphuretted hydrogen was driven out of the mass by boiling and a cur-rent of air was passed through the fluid and absorbed in the alka-line fluid. The united solutions on addition of an excess of hydrochloric acid precipi- tated yellow flakes of a sulphur-compound of arsenic which collected on a filter mashed and dried weighed 1.8 grains corre-sponding to 0.743 grains of hydrosulphuric acid. On drying this precipitate became brown arid hard and on sublimation yielded tersulphide of arsenic as already stated besides a quantity of charcoal. That so small a quantity of this sulphur-compound should have been obtained from about six ounces of gallstones is explained by the experience of Bolle who analyzed two gall-stones ouly one of which yielded sulphuretted hydrogen.The residue which remains after the removal of the hydro- PUTREFACTlON OF BILE. chloric acid extract consists of cholochrome with traces only of the original admixtures. The water-extract on evaporation yields a syrup of a faintly acid reaction mainly bile. It is soluble in water and spirits and no crystalline organic compound is deposited from it even after months of repose. But it has the remarkable property of holding in solution and at length depositing in well-defined large crystals phosphate of lime. The alcoholic extract on cooling deposits a small quantity of white granular matter which is collected on a filter washed with alcohol and dried. It consists of cholic acid containing some fatty acid not easily separated.The filtrate has the property of ambergris being amber in reflected and green in transmitted light. It also has a most agreeable odour of musk. After a part of the alcohol has been distilled off and $he fluid has been again allowed to cool flakes of crystalline matter are deposited. They probably consist of cholesterine. After further evaporation a biliary acid is deposited in drops,-amorphous cholic acid. After prolonged standing crystals of the same character as those obtained by alcohol from the deposit in rotten ox-bile are deposited,-crys- tallised cholic acid. Most of them are mixed with a syrup from which they cannot be separated mechanically. This syrup is insoluble in water and becomes resinous after contact with it it has all the properties of choloidic acid.This mixture of acids is boiled for a long time with water which dissolves cholic acid and a light yellow matter,-perhaps choloidic acid though this acid is reported to be quite insoluble in water. However that may be the watery decoction when left to spontaneous evaporation which takes months owing to the formation of a pellicle on the surface at last deposits the very characteristic splendid needles of cholic acid mixed with a granular brown deposit which does not give the cholochrome reaction and may be choloidic acid. The hydrochloric acid extract is of a light brownish colour and perfectly transparent. Evdporated on the water-bath it deposits a black matter which after mixing with water becomes brown and consists of cholochrome yielding the usual reaction.Several subsequent evaporations each yield some of this deposit which ultimately becomes mixed with earths. The earths are phosphates of lime and magnesia which are deposited in a crystalline state when the solution containing but little acid is allowed to stand. By calcination they are freed from organic matter. Ultimately DR. THUDICHUM ON THE there remains a saline mass containing chloride of calcium chloride of ammonium and perhaps some traces of other matters yet to be ascertained. The ingredierits of ox-gallstones according to analyses upon the above plan are the follomirig Bile a residue of the fluid in which the concretions are formed. Cholochrome cholic and choloidic acids cliolesterine a sulphate in some cases phosphates of lime and magnesia carbonates of the same and some ammonia- compounds possibly a sulphate.* Analysis of Putrid Ox Bile.It is necessary to separate some of the white granules from the Auiil in order to show by combustion and treatment with acidu- lated ether that they contain phosphate and palmitate or stearate of lime. The free fatty acid forms an emulsion on boiling with phosphate of soda ’ The principal step in the analysis of this fluid is the filtration and separation of the deposit. A bag of twilled calico is best used for that purpose. When the fluid has percolated the smeary deposit in the bag must be kneaded with cold water as otherwise it is impossible to wash it.When well washed it is mixed with boiling alcohol and boiled with it for some time; it is then again put in the washed calico bag. The filtrate on cooling deposits a large quantity of crystallized cholic acid. The mother-liquor on evaporation yields little cholic and some choloidic acid. That part of the deposit which boiling alcohol did not dissolve is well mashed with alcohol and extracted with a boiling solution of carbonate of potassa. This solution takes up the wliole of the colouring matter cholophaeine and leaves behind a white mass of coagulated mucus mixed with greenish crystals of phosphate of lime which are separated by levigation. From the soda-solution the cholochrome is obtained as the green modification choloctdo-ine by precipitation with hydrochloric acid.The deposit therefore is made up of stearate and palmitate of lime cholic and choloidic acid cholochrome phosphate of lime in crystals and mucus. The port-nine-coloured fluid part of the bile is treated with sulphuric acid in slight excess a large quantity of choloidic acid * I may here allude to the discovery of sulphide of ammonium which Lehmann states to have made in the bile of a boy. PUTREFACTION OP BILE is then precipitated as a pitchy mass which is easily soluble in Rarm alcohol and contains but little cholic acid deposited in crystdine granules after long standing of the alcoholic solution. The excess of sulphuric acid is removed and any free acid neutralized' by boiling the fluid residue with carbonate of baryta.Wheh evaporated this solution deposits resinous cholic acid (which does not decom- pose carbonate of baryta) to be extracted by alcohol. The alcohol causes a crgsta1lizat;ion on standing with the fluid. The crystals consist of sulphate of soda phosphate of soda and taurine to be separated mechanically and in the ultimate mother-liquor of the decrystallized substances some triple-phosphate is obtained as also some chloride of ammonium to be obtained pure by sublima- tion. The alcohol retains the acetate and valerate of ammonia which salts after evaporation of the alcohol yield their acids on distillation with sulphuric acid The addition of this latter acid still precipitates some resinous biliary matters. The fluid part of putrid bile therefore contains choloidate of soda a little cholate a red colouring matter perhaps cholochromic acid taurine valerate and acetate of ammonia phosphate of soda chloride of ammonium and some other as yet undetermined matters.Putrefaction and Analysis of frilumaia Bile. c As human bile can only be obtained in quantity from persons who have died from disease it will not easily afford the materials with which to repeat the experiments instituted with ox-bile which is fresh healthy and normal. Human bile promiscuously collected in the dead-house even allowing it to contain the normal ingredients is mostly vitiated by a large amount of albumen Tyhich enters the gall-bladder by endosrnosis during the interval between death and obduction This albumen coagulates in part during evaporation of such bile on the water-bath,another part remaining dissolved.If then such bile be subjected to putrefaction the process takes place under different conditions and yields therefore different results. 'This difference mainly consists in the circumstance that the alkaline products of decomposition of albumen either neutralize the acid products of the decomposition of bile which mould pre- cipitate insoluble compounds or dissolve them again should they have been precipitated. Deducting the products of the putre- faction of albumen the products of the putrefaction of the bile GUTHRIE ON SOME PERIVATIVE itself are the Same as those obtained fr:orn ox-bile althongh they are k~a different form.Human bile is mostly neutral. When dissolved in alcohol it parts with the mucus and albumen and the filtrate after evaporation of the alcohol 'leaves a residue which is entirely soluble in water and such solution is neutral and not pre- cipitated by oxalic or acetic acid. Sometimes however human bile exhibits an acid reaction; this en similar treatment with alcohol and re-solution in water of the residue yields a plastery precipitate of choloidic acid. When complete precipitation has been effected the filtrate evaporated and the concentrated fluid treated with alcohol prismatic crystals of taurine are sometimes obtained. The solution always yields ammonia. Human bile which has been allowed to putrefy in a stoppered bottle emits a horrible odour is of a reddish brown colour and apart from the deposit perfectly clear it has an acid reaction.With acetic acid it becomes troubled and deposits a resinous precipitate; but the supernatant fluid remains thick and does not become clear even on boiling and standing; the addition of hat alcohol resolves the turbidity.

ISSN:1743-6893    

DOI:10.1039/QJ8621400114

出版商:RSC    

年代:1862

数据来源: RSC

摘要:

GUTHRIE ON SOME PERIVATIVE XI.-On some Dei*iuatiuesfrom the VleJines By FREDERICK GUTHRIE. IV. A CONSJDERABLE number of the substances whose formation and properties I have had the honour of describiiig to this Society in Memoirs I 11 and 111 are non-volatile and uncrystallizable liquids. Hence with regard to them the two so-frequently adopted criteria of honiogencity are inapplicable ;viz. constancy of boiling point and crystalline form. Although this want is shared ' by a yast number of bodies both organic and inorganic-solid liquid and gaseous,-whose homogeniety is never called into question get additional evidence in this direction is not super- fluous. A method peculiarly applicable in such cases is that of fractional FROM THE OLEFINES.solution. It has been already successfully employed in determining the homogeneity of pses; and may be thus proposed. "When a solvent has prtly dissolved a body and the entire body has the same composition as either of the parts (dissolved or undissolved) or if the latter have the same composition as one another then the original substance is simple or homogeneous." No mixture can show this property unless its constituents are isomers or polymers of one another. The lam itself enjoys of course nearly the same amount of truth as the proposition that no two substances are soluble to exactiy the same extent in the same medium under the same conditions unless the solubility of both be infinite. The inverse of the law is untrue to the extent that solution may effect decomposition.The substances which I have submitted to this test arc the two of the substances previously described which seemed most prolific of derivatives ;viz. *Bisulphochloride of ethylene C,H,S,Cl. *Bisulphochloride of amylene C,,H,,S,Cl. * M. Wurz (RBpertoire de Chimie pure ii 337) in noticing these bodies and the two C,H,S,CI,. C1,H&3,CIp remarks :-"SC12 corresponding to SO2 being diatomic it follows that SC12- C1; that is SC1 ought to be monatomic. Nevertheless it is to be observed that the constitution of these bodies may be regarded in another manner by supposing them to contain the diatomic groups,- Sulphide of ethylene (C,H4Sd)" and Sulphide of amylene (CIOH1,,SLY) corresponding to the oxides.These groups on combining with 2 atoms of chlorine form the two following chlorides :-Dichloride of sulphethylene (C4H4SJ)'f C12. Dichloride of sulphamjlene (C,,H "C12. As for the chloride CloH,SIC1 we double its equivalent representing its con-stitution by the formula,- *(Itis known that 2 atoms of oxide of ethylene may unite in order to combiue .with 1atom of water. Hence it is not extraordinary that 2 atoms of sulphide of amylene should join together in order to combine with 2 atoms of chlorine. If this way of looking at the matter is exact we should represent the constitution of tho oxide of disulphamylene aud that of the hydrate of the oxide of disulphamylene by the formulze- Oxide of sulphamylene c H GIOH1O$'}9. "02. I0 10 1 GUTEIRIE ON SOME DERIVATIVES The method was applied as follows :-A few grammes of the bisul -phochloride of ethylene were warmed with alcohol of about 85" until nearly half dissolved.The alcoholic solution was then poured off and the alcohol removed by evaporation on a water-bath and washing with water. The product after drying in vacuo over sul-phuric acid gave the results- I. 0.4436 gave 25*27%C and 4-36H. 11. 0.4280 gave 33*88%S. 111. 0.2838 gave 36.00%C1. Comparing this with the analysis given before of the entire substance me find,- Hydrate of sulphamylene 10 10 2 H2 In reply I would observe :-1. That SCIBhas not yet been formed ; and that therefore speculations as to what its ;'atomicity" might be are premature. Still more so must considerations be as to the effect which the withdrawal of chlorine would have on the hypothetical atomicity of this hypothetical body.2 That in such bodies as ~lO~lOS2~~2~ it seems preferable to suppose that the halogens are arranged in two Lt monatomic' groups than to imagine with M.Wurz that there are two stages of saturation each stage being a biatomic one. This applied to glycols would give,- C,,H ;% instead of {(CI,Hn)/IOd }"2HO &c. 3. Concerning the bodies CnHnS,C1. I admit in regard to some of their reactions we have reason (neither more nor less) to double their formulae than to double the formulae of the ethers. But to write the hydrated oxide of bisulphamylene C1oH~os~{ "O, instead of C,,H,,S,O,HO or CloH, a. , C,OHI*f% 2 H2 is I think a useless complication.It does not represent the formation or properties of the body more clearly thsn the older formula ; and moreover involves the idea of a mixed type," which I have never been able to understand. But I must again insist here upon the uselessness of seeking to establish the formula of a body;- if formiih of bodies at chemical rest are to express their potential recompositions. (See I.) FROM THE OLEFINES. 131 C,H*S’Cl Entire Dissolved requires Substance Portion. C= 25.13 25.93 25-27 H= 4-19 4.32 4.36 S = 33.51 33.47 33.88 c1 = 37.17 36.29 36.00 1oo*oo 100.01 99.51 About the same qusntity of the bisulphochloride of amylene was treated in exactly the same manner. The dissolved portion on analysis gave the following results :-I.0.3934 grm. gave 23*81%S. 11. 0.2677 , gave 25*66%C1 Whence coiparing as before with the composition of the whole substance we have,-C,,H,,S,Cl Entire Dissolved requires Substance. Portion. C = 43.64 43*80 tt f-F = 7%” 7*47 33 S = 23.27 23.93 23.81 C1 = 25.82 24-73 25*66 100*00 99.93 Hence it appears that in both cases the entire substance has virtually the same percentage composition as the dissolved por- tion ; and accordingly under the limitations above specified the homogeneity of both bodies is established. We have already seen the curious relation existing between the bisulphochloride of chlorethylene and the bisulphide of ethyl in regard to the action on both of chlorine.The product in either case is the chlorosulphide of bichlorethylene or the sulphide of terchlorethyl. This identity of product extends also to the bisulphochloride of ethylene. If a few grammes of the bisulpliochloride of ethylene be exposed to a current of dry chlorine the action being carried on for a few hours and assisted at last by the heat of a water- 132 GUTHRIE ON SOME DEKIVATlVES bath a product is obtained which after expulsion of the excess of chlorine by a current of carbonic acid showed the following composition :-I. 0.3824 grm. gave 70a69%C1. 11. 0.438Q.grm. gave 10.63% S. The sulphide of terchlorethylene requires 71.73 % Chlorine 10.63 % Sulphur. So that the action of chlorine is to convert the bisulphochloride of ethylene into the sulphide of terchlorethyl.Towards chzorine therefore bodies of the form CnHnS C1 behave like sulphides of chloriferous radicles inasmuch as the bisulphides of the radicles CnHn+Irgive rise to the same products. On treating CloH$32Cl with oxide of lend or with hydrate of potash we have already seen the chlorine replaced by 0 and by HO,. Doubtless C,H,S,Cl would give rise to C,H,S,O on treatment with PbO. As yet I have only examined the action of hydrate of potash upon C,H,S2 C1. If C4H4S2 Cl and KOHO be both in alcoholic solution the reaction between them on slightly warming is both immediate and complete. The KOHO being employed in slight excess and the filtrate from the precipi- tated KCl having been freed from alcohol by evaporation and washing with water the hydrated bisulphoxide of amylene is obtained piire.On analysis I. 0-4333gave 31.33 % C and 6-67% H. 11. 0.2984 gave 42.26 % S. C,H,SLOHO C reqnires = 31.17 I. 31-33 11. t> H = 6.49 6.67 >> S = 41.56 > 42*26 0 = 20i8 3) f 100*00 FROM THE OIJCFIPr’ES. The hydrate of bisulphoxide of amylene is a yellowish liquid of curious smell ; like the body from which it is derived it acts violently upon the mucous rnembrance. It dissolves in alcohol and ether but is insoluble in water. Further transforiiiations intimately connected with the above and with others previously described are afforded by the replace- ment of the chlorine in by cyanogen and sulphocyanogen.The methdd used in both cases is similar to that employed for the oxygen and peroxide of hydrogen replacements viz digestion of the CloHl,S C1 with cyanide or sulphocyanide of potassium respectively in alcoholic solution. The reaction is very neat. The precipitated chloride of potassium having been separated by filtration the filtrate is evaporated on a water-bath washed with water and dried over sulphuric acid in vacuo. Both products are liquids which can scarcely be distinguished by smell or other physical property. They have however evidently different densities. The first gave on analysis I. 0.2432gave 55.65 % C and 7-60% H. 11. 0.3881 gave 24.66 % S. CIOH18,CY requires I. IT. C = 56.25 55-65 ?9 H= 7*81 7*60 99 S = 25.00 >) 24.56 N = 10*91 > The specific gravity of this body is 1.07 at 13’ C.Since there can be little doubt but that the sulphur and cyanogeii in this substance are not in the same relation as in the sulphocyanides (for if so S,Cy2 would be required to saturate. C,oHlo),it is advisable to call the above body the bithiocyanide of amylene rather than the cc sulphocyanide ” or ‘‘bisulphocyanide.” The product obtained by the action of the sulphocyanide of GUTHRIE ON SOME DERIVATIVES potassium upon the bisulphochloride of amylene gave the following results on analysis I. 0.2336 gave 44.46C and 6-54H. 11. 0.37'68 gave 39.32 S. CloHILS~S~@ requires I. 11. C H = = 45.00 6.26 44.46 6-54 J > S = 40*00 J 3932 N = 8.75 J> 100~00 The specific gravity of this body at 13OC is 1.16.The least ambiguous name which can be given to it is perhaps the bithio-bithiocyanide of amylene. If we now compare the above and previously described beha- viours of the bodies C,H,S,Cl and C,,H,,S,Cl with that of the halide of a radicle of the form CnHn+,X we must at once admit the parallelism of the recompositions in the two cases and therewith admit that bodies of the form CnHnS,C1> behave like the chlorides of the form %Hn+ lC1 towards oxides hydrated oxides cyanides and sulphocyanides. CnHn+,X + IMO = CnH,+,O C,HnS,C1 + MO = C,H,S,O ++MxI MC1 CnHn,,X + MHO = CnH,+,H02 + hlX C,H,S2C1 + MHO = CnHnS,H02 + MC1 I CnHn+,x -t MCy = CnH,+,Cy + C,H,S,Cl + MCy = C,HnS2Cy + MC1I CnHn+,X + MS2Cy = CnHn+,S2Cy + MX CnH,S,C1+ MS,Cy = CnH,S2S2Cy + MCl Hence the rational formula of C,HnS2C1.FEOM THE OLEFINES. towards oxides hydrated oxides etc ,may be written wherein we have the chloride of a subhuryerous radicle for in presence of these bodies the sulphur and hydrocarbon remain together. We here then see a prominent example of the varia- tions in the re-agent producing a corresponding variation in the rational formula. According to this view the bodies ~nI-TIlSP and CnH,S,HO, represent an ether and an alcohol. An additional argument for considering C,oHloSlH02as an alcohol will be found in the fact that on dropping it into a large excess of strong sulphuric acid which is kept cold a conjugate acid is produced having n soluble baryta-salt.This acid will be described subsequently. Again it would appear from a few experiments performed in this direction that the peroxide of acetyl may replace the chlorine in C1,H1,S2C1 by the action of acetate of potash the acetate of bisulphamylene being produced a body which is an analogue of acetic ether. Such derivatives must for the present be reserved. The body C,,HloS2C1 being thus prolific it becomes important to examine the formation and properties of the bodies formed by the union of amyvlene with the separate halogens S and Cl viz ClOHlOS2 and C,oHloC12 The first of these bodies or the bisulphide of amylene is easily obtained by the direct reduction of CloHloS2Cl,by means of metallic zinc.Nascent hydrogen which was at first tried effects too profound a reduction by withdrawiiig a portion of the sulphur. To prepare C10H10S2 an ounce or two of ClOH~,S2Cl is dissolved in alcohol and boiled for some hours with granulated zinc the alcohol being condensed and allowed to fiow back. The greater quantity of the alcohol is then distilled off and the residue washed with water. A coiourless liquid product collects on the surface of 136 GUTHRTE ON SOME DERIVATIVES the water which after washing and drying over chloride of calcium may be rectified. It boils constantly at about 2QQOC. 1. 0*8012gave 30.60 S. 11. 0.2833 gave 58.32 % C and 10.26 H. 111. 0.3270gave 58.26 o/o C and 10.24 H. ClOHlOSL requires I.11. 111. C = 58.82 7 58.32 58-26 58.29 H = 9.80 , 10.26 10.24 10.25 S = 31.38 30*60 7 Y 30.60 100*00 99*14 The specific gravity of the bisulphide of amplene is 0.907 at 13°C. Considerable difficulty attends the formation of bichloride of amy lene. c1OH1oc4 Amylene absorbs clilorine with the greatest eagerness ;but when the two are brought together alone as' also when cold chlorine- water acts upon amylene floating on its surface large qtiantities of hydrochloric acid are formed which points to the occurrence of some chlorhydrogen replacement. The formation of Dutch liquid by the action of pentachloride of antimony upon ethylene suggested the possible formation of C,OHlOC1 by an analogous process. Pentachloride of phosphorus was finely pounded and treated with perfectly dry amylene.No hydrochloric acid escaped a few degrees of heat were evolved and the whole became nearly dry. After having stood for twelve hours the mass was placed in a basin and floated on water. At the end of another twelve hours two layers were found the lower consisting of phosphoric and as experi- ment showed phosphorous acid and hydrochloric acid,-the upper of bichloride of amylene. From the fact that the amylene and pentachloride of phosphorus produced in the first instance a solid it would appear that the complementary PC1 re-united with the amylene to form the unstable body clOH,OPC1, which subsequently underwent decomposition. After washirig FRO31 TIXE OLEFINES.with water and drying the upper layer was rectified. A product was thus obtained which boiled at 141°-147OC. On aualysis I. 053366 gave 49-22% C and 7.40 H. 11. 0.4279 gave 50.88 C1. ClOHlOCf requires I. I I c = 42-55 43.122 39 EI = 7.09 7-10 J CI = 63-36 60*85 ?f 100*00 3 00.50 At 9" C. 'tPiiAdor;de of arnylene has the specific gravity 1.058. It is not improbable that bichloride of amylene may give rise to bicyanide of amylene on treatment with cyanide of potas-sium. Kicganide of amylene may however be prepared in another and wery singular manner It will bc remembered that the gas NO unites directly with amylene to form the body C1,H,,.2N0 (see 111). This fact was used to support the view of NO being a true halogen. The same conclusion is also suggested by the behzlviour of C,,H,,.2N04 towards cyanide of potassium.If C1,H1,.2N0 be dissolved in alcohol at a gentle heat,* and added to an alcoholic solution of cyanide of potassium an immediate precipitate is produced which after washing with alcohol and drying gives a precipitate with nitrate of silver soluble in nitric acid and which on treatment with sulphuric acid gives an amount of sulphate of potash corre-sponding to the nitritc of potash (nitroside of potassium). The alcoholic solution from the nitrite of potash is evaporated on a water bath at about 60°C until the greater portion of the alcohol is expelled The residue is then repeatedly washed with small quantities of water and dried over sulphuric acid in wacuu.The composition of the liquid product was found by analysis to be as follo.\vs:-0.2760 gave 9-16o/o of H. 0.3500 gave 9.16 % of H and 51.26 of C. 0.3079 gave 16-00o/o of N. * An alcoholic solution of CloHloZWO is decomposed on boiling. Chloroform dissolves CloHlo 2N0 abundantly as also does glarial acetic acid. Strong sul-phuric acid instantly decomposes it. VOL. XI\-* L GTTTIIRTE ON SOXE DERIVATIVES The body according to this analysis is the pentahydrate of bicyanide of amylene. The water attached to the cyanide is to be compared to water of crystallization. It is given off on heating the hydrate but remains combined when the hydrate if exposed for any time over sulphuric acid. It may be sufficient here to notice-(1) That five equivalents of water would be essential to the conversion of the cyanide of amylene into pimelate of potash by the action of caustic potash.(2) That my few experi-ments to prepare pimelate of potash from the cyanide have not been successful. The binitroxide of amylene appears also to exchange its NO for 0 1-10 S and S,Cy. Most of these bodies will probably be soon described by those chemists who are engaged in researches on tlie diatomic alcohols.* A body intimately connected on the one hand withC,,H,,2NO, and on the other with the chlorine-derivatives of C10~10S2C1, is the product of the action of HOBO upon Cl,WloS2C1 On warming HO.NO with C,,H,,S,Cl a tempestuous and in some respects complicated reaction is established. One phase of the reaction results in the formation of the products SO, HC1 and C,HO,.showing that a part of the C,,H1,S2C1 has suffered complete dis-organisation. Moreover a copulated sulphuric acid is formed which has a soluble baryta-salt but has not been further examined. The other and more easily applicable reaction is thc formation of II,S NO,NO,' or the nitrosulphide of nitroxamylene. * Dr. Siinpson's preparation of cyanide of ethylene and thence of succinatc of potash will I expect on publication of his analpses throw light on this subject. FROM TFIE OLEFINES. It is this body which appears in the distillate when C,,H,,S,Cl is warmed in a retort with HO.NO, as a heavy liquid of green colour insoluble in water. After washing with water and drying it is pure.grms. 0.2579 gave 34*82%Cand 4*82%H. 0.2620 gave 34-26XC and 5.25o/,H. 0.1838 gave 9*39%S C,,H9S2 NO requires. t. C = 33.89 34.82 3426 J H = 5.08 41.82 5.25 32 S = 9.04 3 ,> 9-39 The nitroxisulphide of nitroxamylene is soluble in ether and alcohol and suffers apparently very easy reduction by sulphide of ammonium. Before leaving this part of the subject it may be in place to offer a view connecting the two nitroxiolefines described with some known bodies. Such connection at mce appears on looking at the following list which might be much extended. Example. CnH, or C,H,(C,Hn Olefiant gas. Ethyl. Zinc-ethy1. CnHn{'m%+1 Ethyl-amyl. Hydride of ethyl. Chloride of ethyl. Dutch liquid.Ether. 22 GUTHRIE ON SOME DERTVATIVES Alcohol. Ethylenic ether. Glycol. Rinitroxide of amplene. Nitroxisulphide of nitroxamylcne. fc Sulphate of carbnnyl.” Ql y cocine. To which might be added the much-formulized acid series :-Hydrated acetic acid. Acetic anhydride. A series such as the above may assert a claim rather as a device for classification than as a method of accomplishing what most formuke profess to perform viz. an index to molecular arrange- ment. To many of what are called homologous aeries methylene plays the same part chemically as the common difference plays in an arithmetic series. Hence the question forces itself upon us Is it possible by means of the successive chemical additions of methylene to advance from an inferior to any superior term of such a homologous series? The doubt as to the existence of methylme and even in the eyes of some as to the possibility of its existence puts a practical end to this question at present.A moment’s consideration shows that the successive formation of all higher terms could be effected by means of ethylene pro-vided two consecutive homologous terms were taken that is terms differing by methylene. Further by means of propylene we could effect the same FEOM THE OLEFINES. 1-41 purpose provided that three consecutive homologous terms were at our disposal to begin with. And so mutatis rnutandis for the othcr olefines. The suggestion as to the possibility of this method of building up was already given in Memoir I wherein the action of zinc-ethyl upon C,,N,,S,Cl was suggested.The subsequent experi- ntents which have been described as to the easy replacement of the C1 in Cl,HloSzC1 by other halogens only confirmed this idea. In zinc-ethyl as far as it consists of zinc and ethyl the ethyl is the halogen. Can then the ethyl froin zinc-ethyl be made to replace the chlorine C,H,S,Cl? aiid what relation will the body thus pro- duced bear to the bisulphide of cenanthyl? If an excess of ethereal solution of zinc-ethyl (as it comes from the digester) be allowed to fall upon the bisulphochloride of arny-lene considerable heat is developed. It is best to allow the heat to moderate itself by the evaporation of the ether and not to cool artificially.Two layers are formed. These are treated separately with water the oil which floats on the surface is taken off and the solid body (oxide of zinc) is exhausted with alcohol. The alcoholic solution and the oil are mixed freed from alcohol by gentle eva- poration washed with water dried and rectified. The product boils almost constantly at about 24Oo-25O0C. It gave on analysis 0.2730 gave 65*310/,Cand ll.22H. 0.4152 gave 65-4%2C and ll.26H. 0.4186 gave 23*72%S C',,H,,S2 requires I. 11. 111. C 64-12 65.31 65-42 I3 H 11.46 11.22 11.26 JJ s 24-42 39 >> 23.72 I__ 1oo*oo 100.32 so that the product has in fact the percentage-composition of bisulphide of Enanthyl. Although I believe by this means to have found the key to the problem of the successive synthesis of ascending terms of' a homo- 142 GUTHRIR ON SOME DERIVATIVES FROM OLEFINES.logous series; it will be more generally acceptable if the above body be termed for the present the bisulphethide of amylene. An examination of the products of recompositiun of this and similar bodies I reserve for a future communication. The bodies which I have had the honour of' bringing before the notice of the Society in this and previous Memoirs are the fol-lowing :-From Ethylene. C4H*S2C1 Bisulphochloride of ethylene. C4H4S2C12 Bichlorosulphide of ethylene. (4 C4H2Sc1 Chlorosulphide of bichlorethylene. (6)C,H,SC1 Sulphide of terchlorethyl. Hydrate of bisulphoxide of ethylene. C4H4S2H03 From Amylene cIOH1of32Cl Bisulphochloride of amylene.c1OH1OS2C4 Bichlorosulphide of amylene. 1OH. c14 Chlorosulphide of terchloramylenc. c1OHlOS20 Bisulphoxide of amylene. C,oHloS2H0 Hydrated bisulphoxide of amylene. ClOH9S2 Bisulphide of fusyl. ClOHlOS2 Bisulphide of amylene c,OHlOC12 Bichloride of' amylene. CloHloCy2+ 5H0 Penthydrated bicyanide of amylene. ~IOHlOS2CY Bithiocyanide of amylene. Bithiosulphocyanide of am ylene. clow1OS4Q C,0H10.2(N04) Binitroxide of amylene. C $3.2(NO,) Nitroxisulp hide of ni troxamylene. C,,Hl0S2C4H5 Bisulphide of oenanthyl. The above are of course merely the equivalent formnlE. The formulae of dl these compounds are on the type C,€I,XX"

ISSN:1743-6893    

DOI:10.1039/QJ8621400128

出版商:RSC    

年代:1862

数据来源: RSC

摘要:

143 XII.-Ot& the ainount of Water displaced fiom the Hydrates of Potash Soda and Barytu by Boraeic and Silicic Acids. By CHARLES L. BLOXAM. INa communication which mas printed in the Society’s Journal of July 1859 I described a series of experiments upon the action of boracic acid on the carbonates of the alkalies and alkaline earths at high temperatures from which it appeared that at a bright-red heat one equivalent (34.9) of that acid is capable of expelling from carbonate of potash one equivalent (22) of carbonic acid from carbonate of soda two equivalents ;from carbonate of lithia two and a half equivalents; from carbonate of baryta two and a half equivalents ;and from carbonate of strontia three equivalents of carbonic acid. It would be inferred from these results that one equivalent of boracic acid is capable of combining with three equivalents (and perhaps even with more) of a basic oxide of the type MO and that its capacity for bases could not be fully satisfied by its action upon the carbonates of the more powerful bases on account of the energy with mhich they retained their carbonic acid.It might be expected that since the water is more easily expelled from the hydrates than the carbonic acid from the carbonates the former would allow the boracic acid to satisfy its capacity for bases far more readily and it might be hoped that a limit would be found to the displacing power of thisacid for water. In the experiments made to determine this question with the hydrates of potash and soda fair specimens of the fused hydrates were heated to dull redness in a silver tray enclosed in a glass tube through which a current of air was drawn by an aspirator the air having traversed before entering the tube a wash-bottle with strong potash a wash-bottle with oil of vitriol a U-tube with fragments of fused potash and a second U-tube with pumice and oil of vitriol.The composition of the hydrates fused under these circumstances until of constant weight having been carefully determined fresh quantifies were fixsed in the tray and weighed in the corked tube at intervals of ten or fifteen minutes until their weight ceased to vary to any important extent. A weighed quantity of freshly fuscd boracic acid was then introduced a$ rapidly as possible the tube and its contents being again weighed in case a little water or carbonic acid should have been absorbed from the air.Heat was their gradually applied to the tube and the boracic acid fused with the hydrate in the current of pure and dry air iintil the weight of the (corked) tube arid its corrtents ceased to vary to any extent capable of afl’ecting the result of the experiment. At the conclusion the tenipatnre was always high enough to soften the hard glass tube an Argand gas-lamp being employed and a hood of sheet platinum being placed over the heated part of the tube. Since in this way tlie boracic acid was allowed to act upon the same sample of hydrated alkali which had already been subjected to the same conditions until it ceased to lose weight any loss which was suffered during the fusion with the boracic acid must represent the amount of water displaced from the hydrate by that acid.In many of the experiments a weighed chloride of calcium tube was introduced between the fusion-tube and the aspirator and after this had ceased to gain any water from the fused hydrate alone the boracic acid was introduced arid the expcrimerit continued until the drying tube suffered no increase of weight. The gain of the chloride of calcium tube was found to corrF-spond almost exactly with the loss of the fusion-tube. Action of Horacic Acid upon Hydrate of Potash at n Fed heat A somewhat unexpected difficulty arose in the course of these experiments from the tendency of the fused hydrate of potash to absorb oxygen when heated in a current of air.When 50 grains of the hydrate which had been heated to fusion in the silver trap and maintained in fusion for half an hour in the stream of dry and pure air were allowed to cool and dis- solved in water 0.4 cubic inch of oxygen escaped with rapid effervescence and grey spangles of silver separated. The loss suffered by the silver tray in the course of the experiment amounted to 0.14 grn. arid the corrosion of the tray was evident soon after the commencement of the fusion from the appearance of lustrous spangles of silrer in the clear fused hydrate. The fused masses obtained with hydrate of potash arid boracic acid effervesced very rapiclly with water from tlie evolution of oxygen and allowed inky black flakes to scpamte wliiclr appearetl to be simply silver in a finely divided state.~i:ox HYDRATES OF POTASH mc. In order to ascertain to what extent this absorption of oxygen would interfere with the determination of the amount of water displaced by the boracic acid the tube containing the fused mass was heated until its weight was very nearly constant and a weighed drying tube was then attached to the fusion-tube; on continuing the application of heat for half an lzour in a current of dry and pure air the fusion-tube with the hydrate had lost only 0.02 grn. whilst the drying tube had gained 0.17 grn. of water showing that the absorption of oxygen by the fused hydrate was attended by a disengagement of water.Oil dissolving the fused mass in water 0.5 cubic inch of oxygen was collected the weight of which would be 0.17 grn. so that it would have exactly counterbalanced the loss of water. Doubtless the oxygen absorbed is not exactly equal to the water expelled; but it was proved by several experiments that the difference between the two weights was not sufficient to agect the result of the experiment. In no case of the fusion of boracic acid with hydrate of potash was more than 0-5 cubic inch of oxygen disengaged when the mass mas dissolved in water. In order to ascertain the composition of the specimen of hydrate of' potash employed and to prove that when subjected to the con- ditions of the experiment the potash remained in combination with a single equivalent of water the following experimerits were made.1. 29.16 gras. of a good specimen of the fused hydrate were fused in the silver tray in a current of pure dry air for fifteen minutes till the hydrate began to vokttilise slightly. The loss amounted to 3.56 grns. or 12.2 per cent. representing the extraneous water. On further heating for ten minutes it gaincd 0.03 grn. 25.04 grns. of this fused mass dissolved in water and tile carbonic acid determined in Fresenius and Will's apparatus gave 0.8 grn. carbonic acid or 3-19 per cent. 2. 27.96 grns. of the hydrate which had been fused till it ceased to lose weight were dissolved in water and the total amoiint of available alliali determined by neutralising with hydrochloric acid of known strength.The (alkaline) potash present amounted to 22.79 gms. or 81.5 per cent. Deducting from this the weight of potash required to combine with the carbonic acid viz. 6.8 grns. there are left 74.7 grns. of potash present as hydrate which would give 89.0 per cent. of hydrate of potash. 146 ELOXAM ON WATER DISPLACED The solution neutralised with hydrochloric acid was evaporated to dryness the residue ignited and weighed; it gave 36.64 grns. which contained 0.37 grn. of sulphate of' potash and 0.36 grn. of chloride of calcium leaving 35.91 griis. of chloride of potassium representing 22-65 grns. of potash or 81.0 per cent. Deducting from 100 parts of the hydrate the sum of the constituents thus determined (t7iz. potash carbonic acid sulphate of potash and lime) amounting to 85.24 grns.there are left 14.76 grns. to represent the water of hydration. The amount of water required by theory to combine with the 74.7 of potash present as hydrate would be 14.3 grns. Since the sample contained small quantities of alumina silica and chloride of potassium it map fairly be concluded that one equivalent of potash was combined in the fused hydrate with one equivalent of water. The hydrate of potash fused till it ceased to lose weight con- tained therefore in 100 parts Hydrate of potash 89.00 Carbonate of potash 9.99 with a little lime alumina sulphuric acid silica and chlorine. Three experiments were made upon the action of boracic acid on the hydrate of potash with the results exhibited in the sub-joined table.Actual weights in grains. Nun,ber of equivalents.* Boracic Acid. Hydrateof Potash$. Katcr expelled. Boi acic Acid. Hydrateof Pdtash. Water expelled. I. 9-92 41 90 5.01 1 2.60 1.96 11. 9-28 41-69 4.76 1 2*iO 1.98 111. 4.96 31.78 2-69 1 3.98 2 02 In the last experiment the air after leaving the tube in which the fusion was conducted passed through a bottle containing lime- water which gave not the least indication of the presence of carbonic acid. The mean of the last two experiments would give exactly two equivalents (18) of water displaced by oric equivalent (34.9) of boracic acid from an excess of hydrate of potash. * Fquivalcnt of boracic acid = 34.9 ;liydrate of potash = 47 ;water = 9. + Calculated from thc result of the prcliminnry mdjsis.FROM HYDRATES OF POTASH ETC. Action of Boracic Acid upon Ilydrute of Soda at a red heat. Hydrate of soda attacked the silver tray very slightly its wcight in some experiments not having perceptibly diminished ; and the fused mass evolved hardly a trace of gas when dissolved in water. The sample of hydrate of soda employed when fused till its weight was constant lost 1.27 per cent. of extraneous water. The hydrate ihus freed from water was analysed as in the case of hydrate of potash and was found to contain in 100 parts Hydrate of soda 90.41 Carbonate of soda 4.02 with a little alumina silica lime chlorine and sulphuric acid. The subjoined table exhibits the results of three experiments upon the action of boracic acid on the hydrate of soda.Actual weights in grains. Pu’nmber of eqrrivalents*. Boracic Hydrate Water Boracic H-j-drate Water Acid. of Soda.$ expelled. Acid. of Soda,. expelled. I. 4.89 31.91 3.71 1 56 2-95 11. 4 46 35.78 3.43 1 7.0 2.98 *7 J> 1II.S 2-67 2 I0 1 3 04 The mean of these experiments would give exactly three equivalents (27)of water displaced by one equivalent (34.9) of boracic acid from an excess of hydrate of soda. Action of Boracic Acid upon Hydrate of Baryta at a red heat. Since it was pro-ved by experiments described in a former com- municationf that hydrate of baryta when fused in a silver crucible till of constaut weight is represented by the formula BaO.HO the experiments upon the quantity of water displaced from it by boracic acid were made in a closed silver crucible.Crystallised hydrate of baryta the purity of which had been ascer- tained by a quantitative analysis was efliorescedin vacuo over oil of vitriol until it was converted into the compound BaO.HO + Aq.$. The proportion of water having been verified by direct * Equivalent of soda = 31 .t-Calculated from thc result of the preliminary analysis. $A fresh quantity of boracic acid was added to the fused mass in 11 and the cxperimcnt continued. ‘jQuarterly Journal Chem. Eoc. April 1SGO. experiment a .cveighect quantity of the hydrate was rapidly and intimately mixed with a weighed quantity of pure boracic acid dried at 212"Fah. which had been previously slio.vlrn to have the composition €10.H0,.The crucible was then covered and heated until it ceased to lose weight. By subtracting from the loss of weight suffered by the contents of the crucible the meiglit of water known to be expelled by heat from the effloresced hydrates of baryta and boracic acid the amount of water really displaced from the hydrate of baryta by the boracic acid mas inferred. In the following table the results of four experiments of this description are recorded. Actual might in grains. Number of equivalents*. Boraoic Acid Hyclrttte of Rarjta Water Boracic Hydrate Water (H0,B03). (IhO HO + Aq.) espelled. Acid. of 13iuytn. expelled+. I. 317 27.36 ti 36 1 4 00 2 92 TI. 3.00 22.93 4 86 1 3.55 3 12 TII. 2.51 21 60 6-17 1 4.00 3 11 IY.2-96 25.47 4.S7 1 4.00 3 03 From the mean of these experiments it appears that almost exactly three (3.045) equivalents (27) of water are displaccd by one equivalent (349)of boracic acid from an excess of liyclrate of baryta . If the equivalent of boracic acid be taken as 34.9 it displaces from Lydrate of potash two equivalents and from the hydrates of soda and baryta three equivalents of water. Now it was found in the experiments cited above that one equivalent of boracic acid displaced only two and a half equivalents of carbonic acid from the carbonate of baryta though it displaced three equivalents from the carbonate of strontia whicb stands in the same position with respect to the carbonates as hydrate of baryta does to the hydrates that is the next in the series of carbonates (carbonate of lime) is decornposible by heat alone just as hydrate of strontia (the next in the series of hydrates).If it be granted that the watcr in hydrate of barpta is more easily displaced than that in hydrate of soda it ^follows that since boracic acid displaces no more water from the former than from the latter its capacity for bases must be satisfied by the three equivalents of soda or baryta with which it tlieii combines as by * Equivalent of bnryta = 76 ti. .1-After dciluctirig that clue to tile iuatcrini5. F ROX HYDRATES OF POTAS€T ETC. the three equivalents of strontia with which it combined when heated with the carbonate. If the number 34.9 be retained for the equivalent of boracic acid it must therefore be regarded as a tribasic acid ;a view which may be thought to receive some support from the following con- siderations.Boracic ether is represented upon the ethyl hypothesis as 3C,H,O.'BO, and its analogues in the methyl and amyl series have a similar composition. Crystallised boracic acid bas the formula 3HQ.BQ3. Borate of magnesia obtained by Rammelsberg by boiling a solution of borax with sulphate of magnesia had the composition 3MgO. BB,. Octohedral borax and common borax dried at 212' I?. have the composition NaO.fLB0 + 5H0 which may be represented as a tribasic salt if the water be considered to play the part of a base. Thc biborate of potash according to Laurent has a similar composition K0.2B0 + 5130.A terborate of potash obtained by Laurent had the composition K0.3B0 + 8H0 which would also be a tribasic salt if the mater were admitted into the formula The tendency of boracic acid to form acid salts and double salts is not observed in acids which are undeniably monobasic. Action of Silicic Acid upon Hydrate of Potash at a red heat. The experiment was conducted in exactly thc same manner as in the case of boracic acid. The fused mass of silicate of potash dissolved in every case entirely in water with the exception of a few white lustrous flakes of silver disengaging oxygen with rapid effervescence The largest quaiitity of oxygen disengaged (from a mass containing 40 grains of hydrate of potash which had been fused for about an hour in all) mas 0.9 cub.in. which would weigh 0.31 grn. and wonld be at least partly compensated for (as shown by the experiment previously cited) by a corresponding dis- placement of water from the fused hydrate. The annexed table contains the results of four experiments. Actiial weights in grains. Number of equivalents." Silicic Acid. Hxdrate of Potash?. Water expelled. Silicic Acid. Hydrateof Potash. Water expelled. I. 4.65 31.46 2-15 1 3-6 1.54 ir. 4.64 41.23 2.26 1 4.7 1.62 rn. 5.20 32.17 2.44 1 3.3 1.45 IV. 4.97 31-21 2.29 1 3.3 1.53 * Equivalentj of silicic acid (SiO-) = 30. .t.Cdculated from the result of :lie preliminary analysis. BLOXAN ON WATER DISPLACED The silicic acid used in these experiments had been prepared by the fusion of sand with carbonate of soda and carefully purified from all soluble ingredients by the usual processes.It appears from these experiments that the proportion of water expelled increases to a slight extent with the proportion of hydrate of potash employed; but if the mean of experiments I 111 and IV be taken we have almost exactly 1.5 eqs. (13.5) of water displaced by one equivalent (30) of silicic acid from an excess of hydrate of potash at a red heat* Action of Xilicic Acid upon Hydrate of Soda at a red heat The same specimen of silicic acid mas used for these experi- ments together with the hydrate of soda employed in the case of boracic acid Actual weights in grains. X'umbcr of equivalents. Silicic Acid. Hydrateof Soda+.Water expelled. Silicic Acid. Hydrateof Soda. Water expelled. 1. 4.83 35.75 2-94 1 5.5 2-02 11. 491 34-04 3.03 1 52 2 05 These results indicate that almost exactly two equivalents (18) of water are displaced by one equivalent (30) of silicic acid from an excess of hydrate of soda at a red heat,* Action of Xilicic Acid upon Hydrate of Baryta at a red heat. The experiments with hydrate of baryta and silicic acid were attended as might be expected with more difficulty partly from the want of fusibility of the silicate of baryta and partly from the disparity in the equivalent =lumbers of these bodies. The first three experiments in the table were made in a covered silver crucible and the fourth i; the silver tray heated in a current of dry and pure air.In experiments I1 and 111,the silicic acid (in 11,prepared from sand in 111pure rock-crystal) mas mixed with effloresced hydrate of baryta the extraneous water having been determined by pre- liminary analysis and allowed for in the calculation. In I and IV the hydrate of baryta was fused till it ceased to * Col. Y or be found that 30 parts of silicic acid expelled 8.76 of water (0.97 eqs.) from hydrate of potash and 15.7 of water (1'74 eqs.) from hydrate of soda the fusion being effected in a deep crucible. -tCalculated from the preliminary analysis. lose weight the silicic acid then added and the fusion continued till no further loss was perceived. The fused mass in every case gelatinised when treated with dilute hydrochloric acid.Actual weights iii grains. Number of equivalents. Silicic Acid. Hydrate of Baryta(BaO.HO). Water expelled. Silicic Acid. Hydrateof Baryta. Water expelled. T. 1.9’7 21.30 1.09 1 3-8 1-84 11. 3.31 30-47 1.83 1 3.2 1-85 111. 3.61 30.49 1.97 1 3-0 1.82 IT. 2.85 31.78 1.61* 1 3.9 1-85 It may I hope be fairly inferred from these experiments that one equivalent (30)of silicic acid does not displace more than two equivalents (18) of water from hydrate of baryta at a red heat Silicic acid then like boracic appears to have satisfied its capacity for bases in its action upon hydrate of soda when it combines with two equivalents of that alkali since it refuses to displace a larger proportion of water from the hydrate of baryta. If the formula SiO (= 30) be accepted for silicic acid it would be a bihasic acid a conclusion to which the following considerations lend some support.The disilicate of ethyl has the formula BC,H,O.SiO,. The ordinary specimens of crystallised finery-cinder and of the slag from copper-smelting furnaces (melting for coarse metal) have the composition 2 FeO.Si0,. It is also commonly asserted that the most fusible slag from the blast furnace is that in which the oxygen contained in the bases equals that in the silicic acid which is the case in silicates of the bibasic type (2M0.Si02) Berzelius obtained the salts- KO. Al,O,.ZSiO and NaO.A1,0,.2 SiO which are obviously bibasic since A1,0 is equivalent to 3M0. Scheerert has recently found that 30 parts of silicic acid fused with a large excess of carbonate of soda at a high temperature expel 44 parts of carbonic acid.Col. Yorke had previously * Increase of weight of the chloride of calcium tube. The loss of weight suffered by the fusion tube was 1.63 which would give 1-91eqt. of water displaced by 1eqt. of silicic acid. On the supposition that 1eqt. of SiOt had displaced 2 eqs. HO the actual weight of the water should be 1.71 gms. +-Ann. Ch. Pharm. cxvi 129. shown that 30 parts of silicic acid expelleci 44 parts of carbonic acid from carbonate of lithia at a high temperature. The clisposition of silicic acid to form acid salts and double salts does not belong to a monobasic acid. The fonxulze of some of the chief natural silicates constituted upon a bibasic type are herc given.Villarsi t e 2(2Mg0.Si02) i-Aq. Batrachite 2CaO.Si0 +-2M go.SO2* Cerite 2CcO.Si0 + 2Aq. Bucholzite 2A120,.3Si0 Pholerite 2A1,03.3Si0 + Aq. Vesuvian 3340.N20,.3SiO,?. Garnet 3MO.hf20,.3Si0 Scapolite 1 CaO.AI,O,.ZSiO, Anorthite J Sodalitc 3(Na0.Si02-I-Al,O,.SiO,) + NaCI. 7’ _Incon 2Zr0.SiO Ph enaliite 2G10. SiO Helvine G10.Mn0.SiO Hyclrosilicateof nianganese BMnO. SiO -+ 2Aq. ILrpIiolite Mn0.A120,.2Si0 + 2Aq. Electric Calaminc 2ZnO.Si0 + Aq. Hplosiderite 4xgO.2Fe0.3 SO,. Knebelite MnO.FeO.Si0 Cyanite 2A1,0,.3SiO2 (Klaproth) Nisingerite Fe0.Fe,03.2Si0 + 6Aq. Ollivirie 2(MgFe)O.Si0 Several points of resemblance between carbon boron and silicon as well as between their acids lead many chemists to associate them as a natural group.But the atomic weights (6,10*9,and 14) do not exhibit any such simple numerical relation as is frequently to be traced in other groups of elements presenting similar analogies. If the group BO which appears by the above experiments to * According to Mi tscherlich. many fiirnace slags having .the crvvstalline form of olivine have the same composition as batrachite (Gmelin). MOreyrcsenting CaO FeO MnO or Afg-0 md JI-O,,Pe_O or S1-O1. FIELD OK SOME NINERALS FiCOIIl CHILE. represent 3H0 be supposed really to contain 3 atoms of boracic acid the atomic weight of the latter would be -+-%or 11.6 and that of boron 3.6. Again if SiO be supposed to represent 2 atoms of silicic acid the atomic weight of the latter would be +Qor 15 and that of silicon 7.The atomic weights of the three elements would then be Boron . . 3% Carbon . . 6 Silicon* . . 7 The atomic weight of boron added to twice that of silicon would then give (1 7%)nearly thrice that of carbon. If boracic acid be regarded as BO, the atomic weight of boron would be 7.3 or almost exactly half that assigned by Berzelius to silicon (14.8). According to this view the numbers would be CarbonL .6 Boron . . 7.3 Silicon . J4.8 an arrangement more in accordance with our knowledge of the gradations observed in the properties of carbonic boracic and silicic acids such as their displacing power over water their physical states solubility acid character &c.

ISSN:1743-6893    

DOI:10.1039/QJ8621400143

出版商:RSC    

年代:1862

数据来源: RSC

摘要:

FIELD OK SOME NINERALS FiCOIIl CHILE. X1II.-On some MineraIs from ChiZe. By FREDERTCK FIELD. A SHORT paper published in the Journal of this Society (Vol. sii p. 8) on some minerals containing arsenic sulphur and copper from Chile was concluded by the observation that I was then engaged in the investigation of a mineral containing sulphur antimony copper and iron with small quantities of silver the ore being thickly sprinkled mith bisulphide of iron no specimen could * Tf the atomic weight of silicic acid be taken according to Berzelius as 30-8 that of silkon upon the above hypothesis M odd be i.2 ;or if' that given by Pe IOUze (30.2) be employed the atom of silicon would be 7.1 almost exactly double that of boron. VOL. XI\ . nr FIELD ON SOME MINERALS be obtained pure enough for analysis.After much time had been bestowed upon this substance no formula could be deduced as the iron pyrites seemed to be intimately blended with the mineral itself. The discovery of the compound Cu,S ASS analogous to the beautiful silver mineral AgS,AsS rendered it very interesting to find a corresponding Cu,S,SbS to the dark antimonial silver ore AgS,SbS,. All endeavours however as just observed were unsuccessful. The pentasulphide of antimony in com-bination with 3 equivaleirts of disulphide of copper correspond- ing to Guayncanite (the new mineral I described in the papcr above referred to) which consists of pentasulphide of arsenic with 3 equivalents of disulphide of copper is also unknown at present.Further investigations however led to the discovery of many singular specimens some of which though not altogether new to mineralogical science may prove interesting to the Society. Pyotoxide of Copper.-The combination of one equivalent of copper with one of oxygen as a mineral production is rather rare. The suboxide of copper so frequently encountered where the native metal prevails appears upon exposure to the atmosphere or from other causes more difficult to explain to pass at once to the dicar- bonate assuming at the same time both oxygen and carbonic acid. The black earthy looking belt which so frequently surrounds masses of ruby copper and which is described in some works as the protoxide contains as far as my own experience extends a very large proportion of sulphur and although not perhaps a true definite oxysulphide can by no means be regarded as a pro- toxide; in fact it contains no protoxide whatever but is a mixture of disulphide and suboxide of copper.The black oxide of copper had only been lmown as existing in the Vesuvian lavas until the great discoveries in North America both in the valley of the Mississipi and on the borders of lalie Superior revealed this mineral in comparatively large quantities. Quite recently exten- sive veins of copper ore have been discovered in the extreme north of Chile (at longitude 25O S.) consisting essentially of pro- toxide of copper associated with carbonate of lime and a dark lustrous mineral apparently a variety of hornblende.The ore which has a dark brown earthy aspect effervesces strongly upon addition of hydrochloric acid so that at first it might be supposed to be a combination of the metal with carbonic acid; but that this is not the case is evident upon a closer investigation of FROM CHILE. 155 the mineral as well as from the fact that it can be ignited to low redness and maintained at that temperature for some little time without suffering much diminution in weight whereas the car-bonates of copper are deprived of their carbonic acid almost instantaueously when exposed to high degrees of heat. A qua-tat& examination showed the presence of oxide of copper sesqui- oxide of iron carbonic acid lime chlorine water and a substance insoluble in acids. A quantitative analysis gave the following numbers :- Copper .. 36-34 Lime . . 11-61 Peroxide of iron . . 7-87 Carbonic acid 9.32 Chlorine . . 0.25 Water . . 0.28 Residue . . 25.23 90.90 The chlorine in the mineral was associated with copper oxide of copper and water forming the oxychloride of the metal and the carbonic acid with the lime as 11*61of that earth requires 9-12 of carbonic acid to form a carbonate and analysis shews 9.32. The greater part of the copper evidently exists as protoxide and the constitution of the mineral may be thus expressed:- Oxide of copper . . 4292 Oxychloride of copper (3Cu0 CuCl 4HO) . 2.89 Carbonate of lime . 20.73 Peroxide of iron . . 7.87 Residue . . . 25-23 Loss . . 0.36 100*00 If the impurities be removed viz.the residue insoluble in acids peroxide of iron and carbonate of lime we obtain Oxide of copper . . 93.69 Oxychloride of copper . 6-31 100.00 1c3. 2 FIELD OW SO%E NINERATAS Black Amorphous Sukhate of Lead.-An exceedingly curious form of sulphate of lead was found in a mine a few leagues W.W. of Coquimbo. It occurred in large black masses in the centre of which a small vein of finely grained galena was running. The sulphate having a black earthy appearance with no trace of metallic lustre was rejected by the miners as worthless. Its high specific gravity proved however that it consisted essentially of a compound of one of the heavier metals and analysis shewed that it was sulphate of lead colonrcd with a small percentage of pro-toxide of iron.Hydrochloric acid at the boiling temperature decomposed it errtircly formitig a pale green solution due to pro- tochloride of iron or rather perhaps protosulpfinte as free sul- phiiric acid existed in the liquid and on cooliiig the greater part of the lead was deposited as chloride. Sy. gr. of the mineral 6.20 100grs. yielded Sulphate of lead . * 96.73 Protoxide of iron . 3.16 Silver . . traces 99.90 The galena which formed as it were the nucleus of the mass contained (as is generally the case with the fine-grained sulphide of lead) appreciable quantities of silver far more so than the exterior sul ph ate. Basic PersuZphate of Iron.-Tflis bcautiful mineral has been described in mineralogical treatises as Jibrofeerrite.As however niirnerous sulphates appear to exist among which may he men-tioned Fe203 SO, generally cited in chemical works as the one found natiie in South America an account of the true fibro-ferrite may not perhaps he out of place. This mineral is found in botryoidal masscs each rounded nodule being built up of innumerable silky fibres diverging from the centre and of a pale golden green colour. It consists of two eqiiivalents of sulphuric acid in combination with one of sesqui- oxide of iron (Fe,O, 2SO,) and 10 of water. Calculated. Found. Sulphuric acid . . 32.0 31.94 Peroxide of iron . . 32.0 31.89 Water . . 36.0 35-90 lCO.0 99.73 FROM CHILE. 157' After exposure to the air for afew weeks it loses two equivalents of water and becomes Fe20,,2S0,,8H0 and does not decrease further in weight even after many months.Heated in a water bath at 212"E. it loses 7 atoms of water the residue consisting of Fe20,,ZS0,,3H0 and it requires a very high temperature for the expulsion of the last 3 equivalents. When subjected to a temperature of between 500" to 600' F. for some hours the whole of the water is expelled and a pure bisulphate of peroxide of iron perfectly aiihydro us re mains. Calculated. Found Peroxide of iron . 50.00 49.87 Sulphuric acid . -50.00 49-98 1OO*QO 99-85 When fibroferrite is digested in cold water it is partially dis- solved the solution containing both iron and sulphuric acid and having a slightly acid reaction to test paper.The phenomena produced by the action of boiling water are interesting. The mineral becomes decomposed at a temperature of about 120" F. into an ochreish yellow amorphous substance arid a soluble salt the solution of which is strongly acid. 10.00 grains of fibroferrite were digested in boiling water for an hour and the residue dried on a water bath at 212. This insoluble portion weighed exactly 3.00 grains and yielded an analysis 2.100 peroxide of iron -528 sulphuric acid and -368 water being evidently n combination of 2 equivalents of peroxide of iron with 1 of sulphuric acid and 3 of water Calculated. Found. 2Fe,03 . 70.49 70.00 1S03 . . 17.61 f 7.60 3H0 . . 11.90 12.26 _--100~00 99-86 or 2Fe20,,S0,31Z0. The sulphuric acid in the filtrate was found to weigh 2.640 and the peroxide of iron 1.06 the loss agreeing very closely with the 7 equivalents of water which separated at 212".Sulphiiric acid evidently exists in a free state as well as in combination with peroxide of iron as the persulphate Thus it 158 FIELD ON SOXE MINCRALS appears that 3 equivalents of fibroferrite have split up into 1 equivalent of a very basic sulphate 1of ordinary sesquisulpfiate 2 of free sulphuric acid and water. 3(Fe,0,,2SO3,1OHO) =2Fe,O,,SO + 250 + Fe,0,,3S03 +~€10. The insoluble compound described above is found native and very oftcn associated with fibroferrite. Should the sesquisuiphate of iron and free sulphuric acid come in contact with sesquioxide of iron and water; fibroferrite might he reproduced.2(Fe,0,,3S03 + 280,) + 3Fe,O,f 50€IO=5(Fe,0,,2S03 4-IOHO) It is somewhat singular that from Fg,03 2SO, in which two atoms of acid are united with one of base a compound with two of base with one of acid should be derived. Bournonite.-Bournonite was unknown in South America and I believe in the New World until the year 3838 when I met with it in a mine near Huasco in the northern part of Chile. The specimen was crystallized. Hardness 2.5 ; specific gravity 5.80. It resembled in every respect the samples found in Cornwall and some parts of Germany. 300 grains yielded- Sulphur . . 20.45 Antimony 26.21 Lead . . 4Q.76 Copper . . 12.52 A specimen from Cornwall gave- Sulphur . 20.30 Antimony .. 26-30 Lead . 40.80 0 Copper . . . 12.70 100.10 This mineral is mentioned in the present memoir not only as being the first of the kind found in America but also for the purpose of introducing a few remarks relative to the separation of arsenic and antimony from lead copper and other metals of that group. In 1854 MiV. Rivot Reudant and Daguin published a very interesting paper in the Comptes Bendus wherein it was pro- FROM CHILE. 159 posed to separate antimony arsenic and sulphur from many other elements by digesting the mineral in a warm solution of potash which after a time dissolved the arsenical and antirnonial sulghides and passing a stream of chlorine through the potash solution by which mere formed sulphuric arsenic and antimonic acid.By adopting this means the authors remark the whole of the antimony arsenic and sulphur may be removed from lead copper &c. I have repeatedly tried this process and although in my experiments the mirrerals mere in a very finely divided con- dition complete decomposition especially when antimony was present could not be effected. In most instances much of that element and nearly all the arsenic were dissolved but even after many days digestion antimony was invariably found in the residue. Hypochlorites of the alkalies or alkaline earths do not answer better. Dr. Aug. Streng (Ann. Ch. Pham. xcii 411 and Chem. Gaz. xii p. 269) endeavoured in his volu-metrical determination of lead to decompose galena with hypo- chlorite of lime but without success.I also have tried hypo-chlorite of soda upon that and many other minerals with equally unsuccessful results. Streng however acted upon the galena with strong nitric acid thus converting it into sulphate of lead and then after neutralizing the fluid with potash digested at a tempe-rature a little below 212"F.,with chloride of lime when after some time decomposition was complete the whole of the sulphate of lead having passed into the state of peroxide. When bournonite is treated in the same way chloride of soda being employed instead of the lime-salt a considerable quantity of antimony passes into solution but 2 or 3 per cent. dways remains in the residue. The process answers admirably in the analysis of copper or lead minerals containing arsenic and sulphur.For guayacanite (3Cu,S,AsS5) for example the mineral is finely pulverized digested in fuming nitric acid and evaporated nearly to dryness; hypo- chlorite of soda is then added in considerable excess and the whole boiled for about 20 minutes. All the arsenic and sulphur pass into the filtrate pure oxide of copper remaining undissolved. The same is the case with the sulpho-arsenides of cobalt and niclrel. The stronger solutions of potash and soda in very great excess and after violent ebullition fail to decompose the arseniates of these metals completely; but if a stream of chlorine be passed through the alkaline liquid previous to boiling or which is simpler 160 FIELD ON SOXE MINERALS FXtOM CHILE.a hypochlorite be at one employed no trace of arsenic can be detected in the residual oxides. Double Subhide of Copper and Lead.-This very rare mineral which I discovered in a mine near the silver district of Arqueros consists of three equivalents of disulpliide of copper and one of sulphide of lead differing entirely from CuproplumbiteCu,S 2PbS also from Chile which was analyaed by Plattner many years ago. 100 grs. of the new double sulphide yielded- Copper . . 53.28 Sulphur . . 17.69 Lead . . 28.81 99-78 or 3Cu,S,PbS Calculated. Found. 3cu . . 53.34 53.28 4s . . 17-78 17.69 1Pb . . 28.88 28-81 100~00 99.78 It may be mentioned that this mineral has received the name Alisonite in honour of Mr. Robert E. Alison a gentleman who from his extensive smelting operations in no less than five different points in the Republic of Chile has effected very much in the development of the mineral riches of South America.I observe that the great American Minerologist Dana to whom I sent a short note upon the mineral in question has published it under the name Alismite in his supplement to the last edition of his work. This mineral adds another to the list of the tribasic sulphides vhich have been already discussed in the two papers I have had the honour of transniltting to the Society. Arsenical Rosicler . . 3AgS ASS Antimonial do . . 3AgS SbS Sulphide of copper and arsenic . . 3Cu,S,AsS Guayacanite . 3Cu,S,AsS Alisonite . . 3Cu,S,PbS Mr. David Forbes on his retnrn from Chile published an DAVIDSON ON DIBROMIDE OF ETHYLENE ETC.161 account of a new arsenide of copper in the Philosophical Magazine for last December and has namedit Darwinite. This adds another to the list of arsenides the first of which is Dorneykite and the second Algodonite of which I published an account in the Journal of this Society in 1857. Domeykite . . Cu,As Algodonite . . Cu,,As Darwini t e . Cu,,As.

ISSN:1743-6893    

DOI:10.1039/QJ8621400153

出版商:RSC    

年代:1862

数据来源: RSC

摘要:

DAVIDSON ON DIBROMIDE OF ETHYLENE ETC. 161 XIV.-On the actio?z of Dibrornide of Ethylene on Pyridine. By JOHNDAVIDSON. RECENT researches have proved that the bromides of the diatomic radicals are capable of fixing either one or two molecules of ammonia and the monamines the bromides of a monamonium and of a dismmonium being thus produced. This fact having been hitherto almost exclusively established by experiments with the ethylated bases of the nitrogen and of the phosphorus-series it appeared desirable for the sake of generaliza-tion to extend these observations to the several other groups of' monamines. Among the numerous bases which presented themselves for an examination of this kind the group of basic compounds isomeric with the aromatic bases could not fail to attract my attention.Pyridine picoline &c. discovered by Dr. An d er son are powerful monamines the tertiary character of which is well established by their deportment with iodide of ethyl; the advanced degree of substitution rendered these substances particularly well adapted for the intended experiments. Pyridine as is well known has been obtained in the destructive distillation of coal of certain varieties of shale and of animai substances. The substance* which I had at my disposal was *I am indebted to 1Ir. Sam ue 1 C 1if t of Manchesfer for a coiisiderable supply of pyridine and all the other bases formed in the destructive distillation of coai.-d. W.H. 162 DAVIDSON ON THE ACTION OF DTBROW.DE procured from coal tar.It was separated from the picoline by distillation ; the specimen with which I worked boiled constantly at 118O.5 C. A mixture of pyridine and dibromide of ethylene gradually darkens and ultimately becomes brown ; no crystals however are deposited. On the other hand the reaction proceeds nith great rapidity at 100' C. ;and if this temperature be continued for about three hours an almost black and crystalline mass is formed from which by successive treatment with cold and crystalIisations from boiling alcohol a beautiful bromide cry stallising in silky plates may be eliminated. In preparing this bromide it is aclvisable to add to the mixture of the aiihydrous substances from one-fifth to one-sixth of its volume of alcohol and to digest at 100°C.ia sealed tubes; in this manner the whole liquid solidifies into a silky crystalline mass which being but very slightly coloured is much more easily purified. The new bromide may also be prepared by digesting at 100°C. a mixture of pyridine and dibromide of' ethylene with an equal bulk of alcohol in a flask provided with a condensing tube. This process however is less expeditious and is apt to occasion a loss of pyridine which may be carried off with the alcohol-vapour. The crystalline bromide although not deliquescent is very soluble in water; I did not succeed in getting crystals from the aqueous solution ;it is exceedingly soluble in boiling and only slightly so in cold alcohol. The boiling alcoholic solction solidifies on cooling into a pearly crystalline mass; dilute solutions on cooling or on spontaneous evaporation yield larger plates which are transparent but were never sufficiently well formed for deter-mination.I. When burned with chromate of lead 0.206 grm. of the bromide previously well dried at 100°C. gave 0,316 grrn. of carbonic acid and 0.077 grm. of water. 11. 0.4165 grm. of the bromide when precipitated by nitrate of silver gave 0.452 grm. of bromide of silver. The simplest expression representing these numbers is but the mode of formation of thenew compound shows unmistake- ably that this expression must be doubled and that the compo- *H=l; 0=16; C=12&~ OF ETHYLENE OX PYRIDINE. sition and weight of the molecule of this compound is repre-sented by the formula c12H132Br2 Theory.Experiment. I. 11. C, = 144 41.62 42.69 If H14 = 14 4.04 4.15 Y3 N2 = 28 8.10 9 Y? Br2 = 160- 46-24- , 46-16 346 100.00 Pyridrne therefore imitates tricthylamine and triethylphosphine in its deportment mitli &bromide of ethylene the new bromide being formed by the union of one molecule of the latter with two molecules of pyridine C,H,Br + 2@,H,N == C,,H,,N,Br The constitutioik of pyridine itself is but imperfectly made out. All that we know is that this substance is a tertiary monamine ;the nature of the radicles which replace the hydrogen is as yet unknown. In accordance with our present knowledge pyridine is represented by the expression (C5T1,)’”N; whence the molecular construction of the new bromide may be expressed by the formula The composition of the dibromide is confirmed by the analysis of the chloride and of platinum-salt.~1:chZoride.-Treatment of the dibromide with chloride of silver yields on evaporation of the liquid obtained the correspond- ing dichloride which is a white crystalline exceedingly soluble and deliquescent substance. 0.232 grm. of the dichloride dried at 100°C and cooled in wacuo gave 0.259 grm. of chloride of silver showing 27.62 per cent. of chlorine which is exactly the percentage required by the formula 164 DAVIDSON ON THE ACTION OF DIBBO3IIDE Platinum-salt. -The solution of tfie dichloride yields with dichloride of platinum a pale yellow and apparently amorphous precipitate insoluble in water or alcohol but slightly soluble in boiling concentrated hydrochloric acid from which on cooliug it is almost entirely deposited again in the form of little brilliant yellow plates.I. On burning the platinum-salt with chromate of lead the following results were obtained 0.415 grm. of substance gave 0.36 of carboiiic acid and 0*1006 of water. 11. 0.312 grm. of the platinum-salt on ignition gave 0.1032 grms. of metallic platinum. The formula requires the following values Theory Experiment. I. 11. C, = 144 24.120 23.63 Y? HI4 = 14 2.345 2.67 9) N = 28 4.690 9 ,Y Pt = 198 33.167 YY 33.3 C16 = 213 55.678 >Y >Y 597 1oo*oo The solution of the dibromide when mixed with freshly precipi- tated oxide of silver in the cdd furnishes a transparent colourless and powerfully alkaline liquid which contains the corresponding base viz the hydrate of ethylene-dipyridyl-&ammonium.The existence of this compound in the solution is readily proved by saturating the caustic liquid with hydrochloric acid and adding dichloride of platinum vhereupon the pale yellow salt previously mentioned is immediately precipitated. It was identified by analysis 0,185 grm. of platinum-salt left on burning 0,0612 grrn. of metallic platinum corresponding to 33.08 per cent. the theory requiring 33-16per cent. The hydrates of the diatomic pyridyl-derivatives are how- OF ETHYLENE ON PYItfDINE. 165 ever far less stable than the ethylated diatomic bases in the nitrogen- and phosphorus-series.Even at the common tem-perature and more rapidly so on heating the solution of the free base becomes pink riolct and ultimately ruby-red and deposits after some time a brown powder a peculiar odour resembling that of heliotrope being evolved at the same time. I have not examined more minutely the changes which the pyridine- compound thus undergoes. I will only mention that the solution when it had become coloured no longer yielded the difficultly soluble precipitate with dichloride of platinum a crystalline platiuum- salt being deposited only after a considerable time ; on the other hand when boiled for sowe minutes and separated from the brown compound which is deposited the liquid again gave a yellow amorphous platinum-salt.I have made also a few experiments with picoline homologous to pyridine and isomeric with phenylamine. This base is likewise acted upon by dibromide of ethylene but far less energetically than pyridine digestion for four hours at 100°C. produced but a slight change ;after digestion for several hours at about 150°C. the mixture mas black but had not deposited any crystalline matter; after several days crystals began slowly to form. I have not examined this reaction any further. The above experiments were performed in Dr. Hofmann’s laboratory .

ISSN:1743-6893    

DOI:10.1039/QJ8621400161

出版商:RSC    

年代:1862

数据来源: RSC

摘要:

OF ETHYLENE ON PYItfDINE. 165 XV.-Account of recent researches on the application of Electricity from diferent sources to the explosion of Gunpowder. By F. A. ABEL,F.R.S. Director of the Chemical Estrtblishment of the War Department. THEemployment of electricity as an agent for affecting tIie ignition of gunpowder suggested itself to Franklin,* in 1‘751,and to Priestley in 1767 but it mas not until some years after the *In his ‘‘Letters on Electricity,” dated 29th June 1’751 Franklin says ‘‘I have not heard that anybody in Europe has yet succeeded in firing gunpowder by means of electiicity. We do it in this way a small cartridge is filled with dry powder which is rammed in tightly enough to crush a few grains ;two pointed brass wirex are then fixed in it one at each end so that their points are not further apart than half an inch at the centre of the cartridge wliicli is then placed in the circuit of the electric machine ;when the communrcafion is completed the flame leaping from the points of one wire to that of the other through the powder in the cartridge fires it inst antancousl y.” 166 ABEL ON RECENT APPLICATIONS OF discovery of the electric pile by Volta that earnest endeayotirs were made to apply electricity to military and mining purposes.In 1832 the first experiments on the application of voltaic elcctri- city in this direction appears to have been made by French Military Engineers ;about twelve years afterwards that agent was first successfully enlployed in important blasting operations (such as in England the destruction of the Round Down Clif€' near Dover and of the wreck of the Royal George at Spithead) and from that period until very recently the applications of electricity to mining purposes have been almost entirely confined to the em- ployment of the voltaic current.The methods which have been most generally used up to the present time for the explosion of gunpowder by the direct agency of voltaic batteries of diflerent kinds are so well known to all who have given their attention to experimental electricity that a brief statement of the principles upon which they are based will suffice. The original method and that still principally used in military operatioas when the voltaic battery alone is employed consists in causing the current (at the place where the powder is to be exploded) to traverse a short piece of fine wire made of some metal of inferior conducting power such as platinum or iron which in consequence of the resistance offered by it to the passage of the current is raised to a red heat on completion of the metallic circuit of which it forms a portion.The thin wire is surrounded with fine-grain gunpowder an4 is generally fitted into some simple arrangement which may readily be connected with the circuit- wires and broaght into close contact with the charge to be exploded. The other approved method of affecting the ignition of a cllarge of powder by a voltaic current consists in the employment of an ingenious contrivance first introduced by Messrs.St ath am and 33 runt on and founded upon an observation made in experiments with a submarine telegraph-wire which lid been insulated with gutta-percha impregnated with aulphnr. Some amount of chemical action is exerted between the sulphur and the copper in covered wire of this description in consequence of which the surface of gutta-percha in contact with the wire becomes coated with particles of subsulphide of copper which remain attached to it on the removal of the wire. This coating of subsulphide is a sufficiently good conductor of electricity to assist the passage of a current of low tension across a small interruption in the metallic circuit ;the ELECTRICITY TO THE EXPLOSION OF GXJNPOWDER. 167 heat resulting from the retardation of th.current at such a point is however sufficiently intense to effect the ignition of some very combustible substance. It is obvious that this fact admits of ready application to the construction of an arrangement for the ignition of guapowder in which contrivance a hollow piece of gutta-percha coated .on the interior vith the sub-sulphide of copper is made to replace the fine platinum-or iron-wire above referrecl to. The Statham fuze coiistructed upon this principle has been found under favourable conditions which have been fully discussed in other memoirs relating to this subject to+ present important advantages orer the method of igniting gunpowder by meam of fine wires. Although the employment of voltaic currents for the ignition of charges of gunpowder obviously presents great advantages over the old system of firing mines or cannon (by means of slow and regular-burning matches or fuzes the length and time of burning of which was proportioned to the interval which it was desired should elapse between their first ignition and the explosion of the charge) its application especially to military purposes is attended with an amount of uncertainty which has precluded it from ever acquiring great confidence on the part of engineering authorities.This uncertainty is it need scarcely be said due mainly to the great difficulty of ensuring a sufficient uniformity of action at different periods of time even with the most efficient voltaic arrangements and of securing the safe transport and proper preservation of any battery-arrangement and of the agents necessary for its application.When it is remembered that besides these difficulties there are others not less serious which result from the uncertainty of ensuring proper attention to the numerous little points of vital importance to success connected with such an application of electricity of low tension it will be readily conceived that almost ever since the first practical application of electricity to the ignition of charges of powder the possibility of rendering electricity of high tension available in this direction and of apply-ing to military operations the valuable discoveries of Faraday in electro-magnetism has received from time to time serious attention on the part of military engineers and others specially interested in operations of this kind.Thus experiments furnishing interesting and important results have been instituted on the application of induced currents and of ABEL ON RECENT APPLICATIONS OF frictional electricity to the explosion of gunpowder in Spain France Austria Russia and otlier countries ; and in 3855 Professor Wheatstoiie suggested to General Sir John Burgoyne the institution of an experimental enquiry in this country into the relative advantages offered by electricity of high tension obtained from different sources as applied to the explosion of gunpowder. In consequence of this suggestion a long series of experiments has been carried out by Professor TVh ca t stone and myself by desire of the Secretary of State for War and at first in connection with the Ordnance Select Committee.The most interesting and im- portant of the results arrived at by those investigations will form the principal subjects of this memoir. Although our experiments with volta-induction apparatus with frictional electricity and with the currents induced by permanent magnets were conducted in great measure at the same time it mill be advisable to avoid confusion by giving under separate heads on accoiint of the results furnished with each form of electricity and of the conclusions deduced from them. EXPERIMENTS WITH ELECTRO-MAGNETIC APPARATUS. INDUCTION The first application with practical success of the form of elec-tricity furnished by volta-induction apparatus to military purposes was made in 1853 by a Spanish officer Colonel Verdu who having witnessed the firing of a gun at Dmer by the agency of a voltaic battery at Calais connected with the gun by means of il submarine cable was much struck with the inconvenience rcsult- ing from the necessity of employing very great battery-power for effecting the discharge of gunpowder at considerable distance it having been necessary on tliis occasion to use a battery of 400 of Biinsen’s cells.The first investigations of Colonel V er du were made with the assistance of M. Ruhmkorff and with the induction coil-machine which had been recently perfected by the latter. The success attending the first experiments led to further trials in Spain where Colonel Verdu succeeded with the employment of only one element of Bunsen’s battery in exploding simultaneously six mines in one circuit at a distance of 300 metres.This result was of course obtained by allowing the current to leap across small interruptions in the metallic circuits which were surrounded with a readily inflammable substance and imbedded in the charges of powder. The fuze employed was in fact that of Statham in ELECTRICITY TO THE EXPLOSION OF GUNPOWDER. 169 which the terminals were surrounded by fulminate of mercury. Still greater results were obtained by arranging the mines in groups of five so that each group formed a special circuit; by then briiiging eacb circuit in very quick succession in connection with the instrument the mines were all discharged with a rapidity which had the practical effect of a simultaneous discharge.The reason why Colonel Verdu resorted to this method of operation is that the discharge from an induction coil-machine unlike that from a Leyden jar which will pass through several hundred solu-tions of continuity producing a spark at each interruption becomes PO enfeebled by successive interruptions in the metallic circuit that it is impracticable to ignite with certainty a number of charges in one circuit beyond certain limits which with the fuzes used by Colonel Verdu were very narrow. Pig. 1. The arrangement of charges &c. upon this system is exhibited in Fig. 1 in which a and b represent the battery and coil-machine; c the wire connecting one pole of the latter with an instrument d called a rheotome provided with binding screws for receiving the separate wires c’ which lead to the mines m.These screws are fixed into small copper plates isolated from each other being either let into the wood or separated by strips of glass. The wire c from the coil-machine is in connection with a species of metal finger f,which by means of an insulating handle map be made to describe a semicircle with optional rapidity; and as its one extremity presses firmly upon the instrument at a point near any one of the binding screws it is brought alternately into contact with the several small metal plates with which they are con-nected thus bringing them (and therefore the mines) into connec-VOL.XIV. N 1 70 ABEL ON RECENT APPLICATIONS OF tion with the coil-machine. This is only one of several con-trivances which have been used for producing successive discharges of mines iipon this principle In the above arrangement the wires e’ and the plates of metal E connect the charges and coil- machine with the earth. A method of securing the practically simultaneous discharge of ~t nnmber of mines more effective than the so-called rheotomic arrangement of Colonel Verdu was afterwards devised by M. Savare who appears to have first coiiceived the idea of dividing the circuit into branches over the whole of which a current or rapid succession of currents are distributed on the completion of the circuit with an uniformity regulated by the degree of resist-ance met with in each branch.Thus on interposing one or more fuzes in each branch of the circuit those which happen to offer greater facilities in their construction to the passage of the current would explode first and the fuzes tieing so constructed that the terminals of the wires in them are forced apart by the explosion or fused by the heat generated the further passage of the current in that direction is prevented and the remaining fuzes are in their turn exploded. It is readily conceivable that with the employment of currents of high tension following each other with the enormous rapidity with which they pass off from the coil-machines the discharge of a number of fuzes may be effected by the above arrangement with a rapidity which has practically the effect of a simultaneous discharge.Experiments with this mode of discharge were made at Grenelle in 1854. The arraiige- F1g 2 r / ment of charges discharging instrument connections &c ,is illus-trated hy Fig. 2 which scaxely needs spccial explanation (the ELECTitICJTY TO THE EXPLOSION OF GUNPOWDER. 17€ letters of reference used corresponding in their meaning to those in Fig. 1 and the principal difference being that the branch- wires are connected directly with the mire leading to the machine instead of by the agency of a rheotome.) The Ruh mkorff’s coil appears without doubt to have beenused hg the Russians in their mining operations at Sebmtopol. But the most extensive application hitherto made of that instrument for the explosion of mines has been in the great operations undertaken by Messrs.Dussaut and Rabattu at the Port of Cherbourg in 1854 according to a system organized by the Vicornte du Moncel and which was a modification of Colonel Verdu’s method. At the first trial six mines containing each about 4<,400kilos. of powder were inflamed as with one detonation detaching at once more than 50,000 cubic metres of rock. T7CThen the experiments at Woolwich were first undertaken in 1856 much uncertainty appeared still to prevail regarding the descrip- tion of priming materials best adapted for employment in fuzes to be used with the volta-induction current and the maximum number of charges which could be fired with certainty by means of a powerful coil-machine and a battery of moderate power.Expe-riments were therefore undertaken to obtain information on these points and to ascertain the extent to which an electro-magnetic coil of the best and most portable construction would be likely to resist injury by ordinarily careful use and by transport. The coil-machine used in the first experiments was one of con-siderable size and recent construction prepared by M. R u hm k orff. Another apparatus of similar power but constructed for the Ordnance Select Committee by M. Rulimkorff with especial regard to its service in the field was also subsequently employed in many of the experiments. A battery of cast-iron cells and zinc plates (the dimensions of the latter being 5 in.by 3 in.) was employed as the most economical for general purposes. In the greater number of the experiments the current was made to pass to the charges or fuzes through one mile of copper wire (16 gauge) insulated with gutta-percha the metallic circuit being in many instances interrupted by an earth-connection of about ZOO yards in length. The results furnished by a large number of experiments mere briefly as follows :-Fine-grain or mealed gunpowder was found to be ignited readily by means of the induction-coil with the employment of one N% ABEL ON RECENT APPIJCATIONS OF cell of the battery. Numerous substances of a more highly exp'to- sive character were tried alone and in admixture with gun- powder in order to arrive at the description of priming material most suitable to aid in effecting the ignition of the maximum number of charges by means of the coil-machine.The best results were obtained with fulminate of mercury. The efficacy acd delicacy of the fuze were also found to depend in very great measure upon a proper adjustment of the wire-terminals which it enclosed. The number of charges placer1 in succession in single circuit which could be fired at one time by means of such coil-machines as those used and with the employment of twelve cells of the battery specified above did not exceed eight (and was generally below that number) even when priming compositions of a sensitive character containing fulminate of mercury gun-cotton sulphide of antimony and chlorate of potassa &c.were employed. The -discharge of this number could not however be relied upon wit11 any certainty; and the employment of twelve cells did not appear to offer any decided advantage over the use of only four. The ignition of two charges could be effected almost with certainty by the employment of only one cell and the result appeared to be rendered certain by the use of four cells. By employing a rheotomic arrangement for changing the direction of the current so as to bring wires connected with one or more charges successively into the circuit (as described just now) a considerable number of charges could be fired in very rapid succession. This result was however perfectly certain only when a single charge was brought into the circuit at one time.Upon employiug M. Sav are's arrangement of branch-circuits so as to allow the current wlien established to distribute itself along each divided portion of the circuit and ignite simultaneously or in rapid succession the several fuzes which were introduced five or six charges were exploded at one time and a far more considerable number ignited with a rapidity almost instantaneous ; as when this arrangement is employed the first of the very rapid succession of currents established by the coil-machine passes through and ignites those fuzes which offer the least resistance while the others are fired in their turn by the succeeding currents. This method of exploding a number of charges at once or in very rapid succcssion is undoubtedly more efficient than the best rheotornic arrangement and it renders the operator independent ELECTRICITY TO THE EXPLOSION 03’ GUNPOWDER.17’3 of the uncertainty of firing three or four charges simultaneously when arranged in a simple circuit; for in the latter case if the ignition of the whole number is not perfectly instantaneous the explosion of the first prevents the discharge of the remainder; while in the arrangement just referred to the connection of each fuze with the instrument is independent. In the course of these experiments carried on with the two coil- machines constructed by M. Ruhmkorff (one of which mas as already stated specially prepared for operations in the field) a considerable irregularity was observed in the power of the same machine at different periods although the battery-power employed was to all appearances the same on each occasion,--an irregularity which must be ascribed to defective insulation arising from the deposition of moisture on some portion of the apparatus.It was found that the arrangement attached to the coil-machine known as the condenser and upon which the intensity of the current produced greatly depends was very liable to be put out of order in the transport of the apparatus and by other trifling causes; any derangement of this part of the apparatus was fatal to its efficiency. The perfect insulation of each coil of the secondary wire and other somewhat deiicate portions of the apparatus were also found liable to injury from a variety of sources which it would be very difficult to guard against in the employment of coil-machines for field purposes and by persons not thoroughly acquainted with their somewhat complicated construction and their action.Although therefore the system of exploding charges by means of the induction coil-machines offers several very important advantages over the voltaic battery employed alone (one of the principal being the great reduction efkcted by its use in the power of battery required) its adoption as a general substitute for the old system of operation with the battery cannot be recommended with confidence principally because proper reliance cannot be placed upon the certainty and permanent uniformity of action of the apparatus. Some experiments which I have institnted quite recently combining the use of one of the coil-machines above referred to with that of the new description of fuze devised by me for employment with magueto-electric apparatus (to be presently described) furnished results greatly surpassing in magnitude and certainty any which have hitherto been obtained with volta-indue- tion currents.174 ABEL ON RECENT APPLICATIONS OF Employing only six cells of a small Smee’s battery from ten to fifteen charges were fired with certainty when arrangcd in a simple circuit; fifty charges (arranged in branch circuits in sets of ten) were ignited with the effect of one explosion and there is no doubt that this result might be considerably exceeded with the introd-uction of a larger nuFber of branches into the circuit arrangement.It must be borne in mind that these results were obtained with a coil-machine made by Ruhm korff in 1855. The very important improvementswhich have recently been effected by kadd Bent1ey Ruhmkorff and others in the construction of the induction coil- apparatus have reduced to comparative insignificance the most powerful results furnished by the Ru hnikorE coil as constructed five or six years ago. There is no doubt tliat with the combined employment of the new fuzes and of onc of the larger induction coil-machines of recent construction the simultaneous ignition of several hundred charges could be effected xithout difficulty and that in operations of very great magnitude such at1 instrument may be employed with confidence as the most efficient agcnt for effecting the explosion of mines.WITH FRICTIONAL 11.-EXPERIMENTS ELECTILKCITY. It has already been stated that as early as the middle of the eighteenth century Franklin and Priestly both directed their attention to the application of electricity from the machine to the ignition of gunpowder ; but it mas not until 1831 that an actual application of frictional electricity to mining purposes was first made by 3i3i o s e B S h a w of New York who with fuzes charged with gnnpomder and fulminate of silver succeeded in exploding several mines simultaneously dctaching large masses of rock It is stated by him in his account of the experinients that he was unable to operate during the greater part of the year on accoiint of bad weather.In 1842 and 1843 Messrs. Warrentrap of Brunswick and Got zm an n of Freiburg made more successful experiments. Having effected improvements in the insulation of the condncting wires used and employing fuzes which contained a mixture of sul-phide of antimony and clilorate of potassa they succeeded in ex- ploding from eight to ten mines simultaneously through 78.5 metres. Notwithstanding these results they were compelled to abandon the attempt to employ electricity as a certain agent for the explo- ELECTRICITY TO THE EXPLOSION OF GUNPOWDER. 175 sion of gunpowder on account of the evil influence of atmospheric moisture. In I$& the subject was again brought up by BIr. Char 1 e s Win t e r who succeeded in inflaming powder through a telegraph wire reaching between Vienna and Hetzendorf a dis-tance of 4,906 metres.In 1553 when the first successful results had been obtained in France with the Ruhmlrorff coil the Austrian Government directed the Imperial Engineer Academy to propose a system of exploding charges by electricity to be employed by the Imperial Engineers. The somewhat complicated character of the induction coil-machine and the necessity for the employment of some voltaic battery with it appear to have been accepted at the outset by the Austrian investigators as formidable obstacles to the applica-tion of the apparatus in question to military purposes. Attention was therefore again directed to the application of frictional elec- tricity ; and after three years' experiments a system of operation involving the employment of an electric machine was considered to have been sufficiently successful for introduction into the engineer service.The system in question appears to have fur-nished very important results,. and to have been frequently applied to industrial operations. The electric machine employed is arranged in a very portable form and consists of two discs of polished glass twelve inches in diameter and four lines thick fixed upon one axis within inches of each other and fitted with cushions to which springs are attached. The Leyden jar is cylindrical fifteen inches high and six in diameter (its area being 276 square inches). It is protected by flannel and fixed in a case of lacquered tin being screwed on to an iron plate which is connected with the friction-apparatus.The charging is effected by means of a steel point which projects one inch into the space between the discs and can be pushed into an arm of the conductor. The latter is inserted into a plate of hard caoutchouc which forms the cover of the Leyden jar and is connected by chains with its inner surface. The machine is always covered when in use by a case the sides of which are made of thick leather and the top of tin. A small stove is also fixed beneath it so as to dry the air inside when necessary. The mire employed as conductor is brass which is raised on insulated posts or covered with gutta-percha ;the priming material used in the fuzes was first fulminate of mercury j a mixture of chloratc ABEL ON RECENT APPLICATIONS OF of potassa and sulphide of antimony was afterwards adopted.A large number of experiments mere tried with this arrangement under the various conditions in which it might receive application. The greatest distance at which an inflammation was attempted was four German miles. On several occasions fifty mines were simultaneously discharged in the same circnit ; the fuzes were two klafters (toises) from each other and the electric machine was 140 klafters from the nearest fuze. In like manner thirty-six charges were simultaneously exploded in one of the branches of the Danube; these charges were placed six feet under water and had remained submerged during twenty hours previous to their explosion.Other operations on a large scale in marble quarries in the beds of rivers &c. in which cousiderable masses of matter were displaced are given in detail in an interesting report by Baron von Ebner published in 1855;they place the efficiency of the process beyond doubt. The objections to the system as pointed out in the report referred to are that some scientific skill is required in the manipulations; that great care is needed in the preservation of the apparatus and that the inductive action is sometimes so energetic that explosions are occasionally determined in other mines not intended to be included in the series and not connected with the machine. At the suggestion of Mr. Wheatstone a series of experiments was undertaken for the purpose of ascertaining whether the hydro- electric machine of Sir William Armstrong might not be advan-tageously substituted for the ordinary electric machine for charging a Leyden jar or battery in the field.A small portable hydro- electric machine was constructed specially for the enquiry and placed at the disposal of the experi- menters by Sir William Armstrong. It consisted of a small vertical boiler (supported on a sheet iron stand in which a grate was fixed) of two gallons capacity provided with a safety-valve by which the pressure of steam could be regulated up to 901bs. on the inch. The head of the boiler was provided with a cock to admit of the escape of steam to which was fixed a horizontal iron pipe nine inches in length and of half an inch internal dia- meter and fitted with the jet and wooden cylinder which serve for the issue of the steam and the development of the electricity.The iron pipe was surrounded by a small metal box which when the apparatus was in use was partly filled with water so as to effect a partial condensation of the vapour as it passed through the pipe ELECTRICITY TO THE EXPLOSION OF GUNPOWDER. 177 A brass fork raised to a level with the jet and capable of adjust- ment at different distances from it served the purpose of conduct-ing the electricity from the jet of steam to the Leyden jar or jars which were placed in a sheet-irou casing immediately under the steam-jet. The boiler was very well adapted to the rapid gene- ration of steam of considerable pressure.About twenty minutes after a wood fire was kindled a pressure of 60-7Olbs. was obtained the boiler being one-third full of water. To avoid the possibility of the water in the boiler priming during an operation in which case the charge of a jar with electricity could not be accomplished it was indispensable that the boiler should not contain too large a quantity of water (it was found safest to employ it not more than one-half full) and that the water should be free from solid matter iu suspension. To ensure the fulfilment of the latter conditions it was necessary not only to employ per- fectly clear water but to clean out the boiler after each experi- ment (if spring or river-water were employed) so as to remove all solid matter deposited by the boiling water.With the employ-ment of rain-or distilled water this precaution was of course rendered unnecessary. The time required to charge with elec- tricity a Leyden jar of about 1s square feet surface when the machine was in good vvorliing order was found to be from five to seven seconds. The rapidity with which the jar was charged proved under favourable conditions to be proportionate to the pressure of steam employed the most suitable being from 60-701bs. per square inch. The first experiments on the ignition of charges were conducted with the employment of ody short lengths (from 12 to 50 feet) of wire to serve as connections between the jar and the charges. The machine was worked in a locality sheltered from wind and draught.The priming composition employed in the charges was the same as that ultimately adopted in the experiments with the magnet which will be presently described. Two different plans were available for firing the charges (1.) by completing the circuit before the jar was charged and allowing the fuzes to be fired by its spontaneous discharge; (2.) by allowing a definite time (about six or seven seconds) for the charging of the jar before completing the circuit. The first method would be preferable for the ignition of a very large number of charges in the same circuit as the em-ployment of the maximum charge attainable would thus be secured If' however the ignition of the charges had to be effected at 178 ABEL ON RECENT APPLICATIONS OF a given time it would be necessary to employ the secoad method.The results obtained by this apparatus were very variable. On one or two occasions (five seconds being allowed for the charging of the jar) it was found impossible to fire six charges placed in a simple circuit simultaneously with certainty ; although when eight and afterwards twelve were connected in a similar manner seven aud eleven were fired the conditions (as to pressure &c.) being apparently the same. Oil another occasion with a pressure of 2'0 lbs. and an allowance of seven seconds for the charging of the jar forty fuzes were placed in circuit and the whole number discharged. One hundred and twenty were afterwards placed in circuit and of these one hundred were instantaneously discharged.Attempts were subsequently made under apparently the same conditions to obtain a repetition of these results but without success. Experiments made to effect the ignition of several charges in circuit through a considerable length (one mile) of covered wire and an earth-connectiou n ere only very partially successful. At first the greater portion of the wire was left in a coil for the sake of convenience aird only a short earth- cmnection (about twenty feet) was employed. Very successful though not uniform results were obtained forty and fifty fuzes (the entire number in circuit) having in some instances been ignited while in others a few were left in different parts of the circuit.Upon uncoiling tlie wire to the extent of about 600 yards and causing the circuit to be completed by the earth these results codd not be in any way depended upon and on no occasion were as many as forty charges fired the number at times not exceed- ing five or six. A feiv experiments made vith small Leyden jars charged with electricity from the ordinary cylindrical machine mere confirma- tory of the comparative imccrtainty in firing a large number of charges through an extended metallic circuit of considerable length. Forty charges were fired by means of a Leyden jar con-taining sixty square inches of surface the electricity passing through about twenty feet of wire-circuit ; but on employing one mile of wire with an earth-connection the ignition of twenty-five charges though once or twice successful could not be depended upon.Attempts were made on two occasions to employ the kydro-electric machine in the field. At Chatham the ruacliiiie was ELECTRICITY TO THE EXPLOSION OF GUNPOWDER. 179 placed in the open air on rising ground and 880 yards of covered wire were employed of whicli about sixty were extended an earth-connection of that length being used in place of a second wire. Two Leyden jars each affording about 13square feet of surface formed the battery. They were enclosed in a stout wooden box and every precaution was taken to have them dry at the com- mencement of the experiments. The time to be allowed for the charging of these jars as determined by previous experiments made in a sheltered locality was about ten seconds with the employment of steam at 70 lbs.pressure The atmosphere was dry and a slight breeze blowing on the clay of experiment. The machine was so placed that the steam-jet should be as little as possible affected by the wind. Repeated unsuccessful attempts were made to fire fifty charges in circuit; these were then gradually reduced to twenty when only five xi ere ignited in different parts of the circuit. It was found impossible to charge the jars to more than a very slight extent. This unfavourable result was ascribed partly to an interference of the slight wind with the steadiness of the jet of steam and partly to the difficulty of maintaining the Leyden jars in a suitably dry condition.The machine was removed to a trench of some depth for the purpose of sheltering the steam-jet from the wind but with no better result. On a second occasion the machine was sheltered from the mind which blew freshly by being placed under a shed. Forty fuzes were placed in circuit with 200 yards of covered wire coiled up and an earth-connection of about twenty feet. The two Leyden jars were employed and the whole of the charges were simultaneously ignited. The wire was after- wards uncoiled and the same number of fuzes were again placed in circuit but these did not fire. On reducing the number to twenty-five nineteen were exploded six being left in different parts of the circuit. These experiments appear to prove begolid doubt that the details or rather the auxiliaries of the hydro-electric apparatus employed must undergo some considerable modifications before anything like definite results can be obtained with it.Arrange-ments for securing the preservation of the jars in a sufficiently dry condition and for. screening the jet of steam fi*om the prejudicial influences of the wind or draught might readily be carried into effect and would unquestionably contribute greatly towards rendering the apparatus more certain in its action. ABEL OX EECENT APPLICATlOSS Ob’ The results above noticed were however sufficiently definite to indicate that in mining operations of a very extensive character the destruction of docks bridges &c.) where it is desirable to ignite a very large number of charges simultaneously and at which as is most generally the case full appliances arid con- veniences are at command for thoroughly fillfilling every condition of success the hydro-electric machine is susceptible of very effective application though scarcely with the same degree of confidence as could be placed in the certainty of action of volta-induction apparatus of recent construction.For general use in the field the hydro-clectric machine even if its appliances are arranged in a much more effcient manner than was the case with the one employed could certainly not be relied upon with the necessary confidence principally on account of the difficulty of ensuring in the field the fulfilment of those conditions which appear essential to the proper generation of electricity by means of the steam-jet.III.--EXPERIMENTSTHE APPLICATION OF PERNANENT MAGNETS ON TO THE EXPLOSJON OF CHARGES AND TO SUBMARINE OPERATIONS. The ignition of gunpowder by the direct magneto-electric current though well known to be practicable has never yet been applied to military or industrial operations and no satisfactory experiments appear to have beeii made before those undertaken at Woolwich shawing its practical applicability to these purposes. In the first experiments on this application of the magneto- electric current a very large powerful magneto-electric machine was employed which had been constructed by Mr Henley (aud had been exhibited by him at the Paris Exhibition in 1855). The principle of this instrument was precisely the same as that of the machine devised by Mr.TV heatstone for ringing magneto- electric bells. Its armature instead of being rotated was sud-denly detached from the magnet bp means of a lever. It was soon esta1)lished by a few experiments that even with this imtru- ment gunpowder itself coiild not be ignited with any degree of certainty. Results obtained with Stath am’s and other fuzes though superior to those furnished by gunpowder alone were still far from satisfactory. The first efforts were therefore directed to the discovery of a suitable agent to mme as a perfectly certain ELECTRICITY TO THE EXPLOSION OF GUNPOWDER. 181 medium (or priming material) for effecting the ignition of charges by means of the magneto-electric machine.For this purpose a variety of compounds and mixtures of a more or less sensitive character were prepared for trial with the magnet. The following were the principal tried mixtures of meal powder with powdered coke with sulphur with sulphur and iron filings with iron filings and carbon with fulminate of mercury and with the latter in addition to iron filings and to coke; fulminate of mercury percussion-cap composition alone and with coke ; detonating com- position (sulphide of antimony and clilorate of potassa) ; the same mixed with iron filings and with coke; gun-cotton alone and mixed with some of the above; amorphous phosphorus in ad-mixture with oxidising agents. It will be observed that the nature of the above materials was varied so as to test the sensitiveness of readily ignitable substances both alone and when mixed with bodies which would serve as electrical conductors.Many of these compositions furnished results to a certain extent favourabie a number of fuzes primed with them having been fired in succession with the magnet and from two to four charges in one circuit having been ignited in a very few instances. But no perfect certainty of discharge was attained with any one of the above materials ;the attempt to fire a fuze being frequently un- swcessful while no difference between it and a successful fuze containing the same composition could be detected by careful examination. These preliminary trials however established the fact that the sensitiveness (ready explosiveness) of a priming material was not alone sufficient to determine its success but that those which possessed a certain though not too considerable degree of conclucting power were more readily and certainly ignited than others of a far more sensitive character.Some successful results obtained accidentally with one of the experimental compositions which had become damp by exposure to air led to a trial of the effect of moisture in promoting the ignition of but slightly sensitive compositions and it was ultimately found that the impregnation of ordinary gunpowder with a small amount of moisture (by an expedient similar in principle to one adopted with considerable success by Captain Scott R.E. in con- nection with charges to be fired by the induction coil-machine) rendered its ignition by means of the magnet a matter of cer-taiiit y .Some important precantions were however indispensable to 182 ABEL ON RECENT APPLICATIONB OF the attainment of this definite result. If the slightly damp powder was employed in a iinely divided condition it very frequently became caked between the wire-terminals ill the fuze and the current would then pass through the composition without igniting it. This was found to take place occasionally even wlnen the powder was employed in its original granular condition. Several attempts were made to overcome this difficulty by modify- ing the form and position of the terminals or poles in the fuze and I at last contrived a perfectly successful arrangement in which only the sectioml surfaces of the terminals consisting of fine copper wire (0.022inch diameter) were Fig.3. exposed in the interior of the fuze (see a fig. 3) so as not to project at all. The prepared gunpowder therefore simply rested upon tlie surfaces and a perfect uniformity in the action of the fuze was attained. The priming composition con- sisted of fine-grain gunpon der which had been soaked in an alcoholic solution of chloride of calcium of a strength suffi-cient to impregnate the grains with from one to two per cmt. of that salt. The prepared powder was cxposed to the air for a short time to permit of a suffi- cient absorption of moisture by the de- liquescent salt. Upwards of 500 quill-fuzes (of the description employed for firing guns) primed with the prepared gunpowder and fitted ~itli the arrangement of the terminals above referred to (fig.3) were fired with the larger lever- magnet. The failures did not amount to more than 3 per cent. and were all proved to be due to defective manufacture. In the experiments with these ftxzes one or two simple rheotomic arrange- ments such as that referred to in the first part of this memoir were successfully employed for effecting the rapidly successive discharge of a series of fuzes. The above fuze was found to be easy of manufacture and per- manently effective. While however it presented a certain means of effecting the ignition by the aid of a powerful magnet of single charges or of a large number to be fired in moderately rapid succession it was inapplicable to the ignition with certainty of more than one charge in circuit.After a great number of experi- ELECTRICITY TO THE EXPLOSION OF GUNPOWDER. 183 ments I at length succeeded in the production of a priming material for the fuze which greatly exceeded in sensitiveness any of thc other compositions hitherto tried. A very gradual separa- tion of the armature from the large magnet sufficed to effect the ignition of the fuzes primed with this material and the induced current obtained by means of a very small magnet with a rotatory armature such as employed in Wheat st one’s magneto-electric telegraph was sufficiently powerful to produce the same result. I have recently found that the currents obtained from magnetic instruments of inferior power and less perfect construction such as the small American magneto-electric medical apparatus readily ignite this priming material and that fuzes primed with it are fired with certainty by the smallest electro-magnetic apparatus with the employment of one moderate-sized cell of S m e e’ s battery .The new priming composition consisted of a very intimate mixture of sub-phosphide of copper chlorate of potassa and levigated coke the latter substance being employed to add to the conducting power of the mixture which mas found otlierwise insufficient. In the course of experiments subsequently carried on with fuzes which contained this composition it was found that a slight residue consisting principally of the coke employed occasionally remained on the surfaces of the terminals in the fuze after its dis-charge and by forming a good conducting link between them interfered with any future effects of the magnetic current in other directions by the establishment of a complete circuit.This obstacle to the perfect success of the composition was entirely removed by the substitution for the coke of another material more easily acted on by the chlorate of potassa and answering equally well as a con-ducting medium ;namely the sub-sulphide of copper. No instance has occurred in the discharge of several thousand fuzes primed with the mixture of sub-phosphide and sub-sulphide of copper with chlorate of potassa in which the termiiials have not been found quite free from adherent residue after the ignition.The sub-phosphide of copper which is produced at an elevated temperature is a compound of very stable character and the mixture of the three constituents is quite as unalterable as the explosive mixtures which are in general use for the preparation of percussion caps &c. The stability of the mixture has already been submitted to very satisfactory tests. Fuzcs primed with it 184 ABEL ON RECENT APPLICATIONS OF have been found to have lost none of their delicacy and certainty when tried more than two years after preparation. Before passing to a statement of the results obtained by the aid of this priming composition in investigating the extent to which magneto-electricity could be applied with certainty to the simul- taneous ignition of a number of fuzes sonie little account must be given of the properties of the priming material itself and of the results which regulated the prpportions in which its ingredients were employed.The sub-phosphide of copper intimately blended with chlorate of potassa forms a mixture in a high degree sensitive to the effect of heat and possessed at the same time of some power of con-ducting electricity. With the employment however of magneto- electric machines of comparatively low power and in cases where the resistance to be overcome by the current is considerable this conducting property is not sufficient to ensure the ignition of the mixture by assisting the passage of the current across the inter- ruption in the metallic circuit (Lev across the small distance between the terminals of the wires in the fuze.) It must be borne in mind that the striking distance or the space between the terminals across which the current from even a powerful magneto- electric machine will leap is very small.With the large lever- magnet the spark could only be produced when the wires were almost in contact. Since however it is indispensable to the proper insulation of the wires in the fuze-arrangement that the terminals should be at least one-sixteenth of an inch apart it will be readily understood how essential to success in operations with these machines it is that the priming material should possess considerable conducting power.Hence the necessity of increasing the conducting power of the mixture of sub-phosphide of copper and chlorate of potassa; a result which it has been already statcd was obtained in the first instance by the employment of finely levigated coke and afterwards by the substitution of sub- sulphide of copper for that substance. Many experiments were of course required to determine the proportions in which it was advisable to employ the conducting constituent so as to facilitate the passage of the current through the mass as far as possible without interfering too much with the sensitiveness of the explosive mixture or producing an almost perfectly continuous connection between the two poles in the fuze and thus promoting the passage of the current so greatiy as to prevent the ignition of the composition.ELECTRICJTY TO THE EXPLOSION OF GUNPOWDER. 185 Considerable difficulties were encountered in the endeavours properly to balance these conditions when attempts were made which will presently be mentioned to apply the mixture in ques- tion to the ignition of several charges in circuit. The increase in the resistance of the current consequent on the introduction of more than one interruption in the metallic circuit necessitated an increase in the conducting power of the mixture which it was difficult to attain unless at a considerable sacrifice of tlie sensi- tiveness of the composition. It wm consequently found that when the proper conditions had been attained for ensuring the passage of the current through several (five or six) fuzes in circuit the absolute certainty of the fuze when applied in this manner had been sacrificed.Thus out of several fuzes tried together which had been most carefully prepared so as to be as far as possible perfectly alike the current would ignite a few passing through the others without affecting them; and would thus point to minute differences in the conducting powers and sensitiveness of different portions of one and the samc quantity of the mixture which it is almost needless to observe was prepared in such a way as to ensure the greatest possible uniformity. By a large number of careful experiments the proportions of ingredients were at length determined which furnished a mixture possessed of high conducting power attainable without detriment to the sensitiveness (ready explosiveness) of the material.The perfect certainty of its action when applied in the fuze to the explosion of a siugle charge by m eans of magneto-electric machines has been proved by the ignition of at least 5000 fmes without failure. A large number of these have been fired by means of the smaller machines already referred to. The fuzes contrived by me for use with magneto-electric appa- ratus are of two kinds the one being adapted for mining purposes and the other for firing cannon. The fuze for mining purposes (fig. 4) consists of,- a. A head for receiving the wires which connect the fuze with the magnet and the earth; b. Of the insulated wires with the terminals of which the priming material is in close contact ; c.Of a small cartridge or charge of powder enclosing the ter- minals upon which the sensitive composition rests. The wooden fuze-head contains three perforations (a a b b c c fig.5) ; the one passing downwards through the centre receives VOL. XlV. 0 ABEL ON RECENT APPLICATIONS OF 186 about two inches of double insulated wire d* The other two perforations which are parallel to each other on each side of the central one and at right angles to it serve for the reception of the circuit-wires. The arrangement for securing the connection of these with the insulated wires in the fuzes is as follows :-The piece of double covered wire above referred to is originally of a sufficient length to allow of the gutta percha being removed from about one and a-half inches of the wires.These bare ends of the fine wires which are made to protrude from the top of the fuze-head (a fig. 5) are then pressed into slight grooves in the wood provided for their protection and the extremity of each is passcd into one of the horizontal perforations in the head in which position it is afterwards fixed by the introduction into the hole of a tightly-fitting piece of copper tube so that the wire is firmly wedged between the wood and the exterior of this tube and is thus at the same time brought into close contact with a compa-ratively large surface of metal. It mill be seen that it is only necessary to fix one of the circuit-wires into each of these tubes in * This double covered mire consists of two copper mires of 0.022 inch diameter enclosed side by side at a distance of & inch apart in a coating of gutta percha of 4 inch diametcr.It has been prepared by the C-utta Percha Company for this particular purpose in considerable lengths (300 yards) from R hich the pieces of requisite length are cut off as required. ‘I he insulatlon of the tt\ o wires has been found perfect throughout the uhole length manufactured at one tlmc. ELECTRICITY TO THE EXPLOSION OF GUNPOWDER. 187 the opposite sides of the fuze-head in order to ensure a sufficient and perfectly distinct connection of each one of them with one of the insulated wires in the fuze. The pliosphide of copper fuze for firing cannon (fig.6) differs somewhat in construction from the mining fuze The head is somewhat longer and of such a form that the double-covered wires are completely enclosed in it the lower extremity of its central perforation still remaining free to receive the top of the quill-or copper-tube which is charged with gunpowder in the same manner as the ordinary tube-arrangement for firing cannon. Numerous experiments made with the aid of the detonating mixture with which these fuzes were primed established the fact that the current ob- tained by means even of a very powerful magneto- electric machine when applied to the ignition of several charges arranged in succession in one circuit is very limited in its powers. In illustration of this it may be stated that on trial being made of twenty-one consecutive sets of four charges eighteen of the sets were perfectly discharged but in the other three sets only two or three of the chArges were ignited.Out of five sets of five charges each only two sets were completely discharged ; and in several attempts made to ignite six fuzes in one circuit only four were fired in each case. In all these experiments when charges had escaped ignition the current had passed through the sensitive composition without firing it. When the discharged fuzes were removed and the remaining ones pro-perly connected they were all fired. It has been already stated that no beneficial effects were attained by modifying the propor- tions of ingredients in the priming composition so as to diminish or increase its conducting power.Three charges might therefore be considered the largest number that could be ignited with certainty by means of a powerful electro-magnetic machine when they were arranged in succession in simple circuit. The plan originally suggested by Ill. Savare of arranging the charges in divided circuits was next tried and furnished far more successful results. The simultaneous ignition of twenty-five charges arranged as shown in fig. 2 was repeatedly 02 ABEL ON RECEKT APPLICATIONS OF effected; and forty charges vere similarly exploded on several occasions. These results were all obtained with the large magnet constructcd by FI eril ey the current being established by rapidly separating the armature from the poles by means of a lever.By a simple arrangement for shifting the connection of the main wire with the exploded charges from them to a second series similarly arranged twenty-five were almost simultaneously ignited on allow- ing the armature to return to the poles of the magnet. It was found moreover that the same number could be fired by means of this magnet even if two folds of thick brown paper were interposed between the poles and the armature so that on depression of the lever the armature had no longer to be forcibly detached but simply to be removed from the magnet. The success of these results led to trials of magneto-electric machines of comparatively small size with revolving armatures. In the employment of these machines it was of course not expected that my single induced current obtained from them should distribute itself among a number of fuzes placed in divided circuit as is the case with the comparatively much more powerful current obtained with the large magnet but it was hoped that the very rapid siiccession of currents furnished by them would produce a very similar result by distri- buting themselves over the different branches of the circuit with which the fuzes were connected and that the ignition of the whole of the fuzes though it could not be so positivelyinstantaneous as when the one current was discharging the entire number might yet be effected with such rapidity as practically to amount to a simultaneous discharge.The resulCs obtained fully confirmed these expectations.With a small horse-shoe magnet 7 inches in length 1inch in breadth and 12inches in thickness provided with a revolving armature and multiplying wheels by which great rapidity of motion could be attained twenty-five charges were fired ;the effect of the discharge on the ear was however not like that of one single explosion as was the case in the former experimetits but like that of an exceed- ingly rapid volley in which the explosion of any single charge could not be distinguished. Still more favourable results VI ere obtained with a very compact arrangement consisting of six small magnets to the poles of which were fixed soft iron bars surroundecl by coils of insulated wire. The coils of all the magnets were united together so as to form mith the external conducting wire and the earth a single circuit.An axis carried six soft iron ELECTRICITY TO THE EXPLOSION OF GUNPOWDER. 189 armatures in succession before each of the coils. By this arrange- ment two advantages were gained ;all the magnets simultaneously charged the wire and produced the effect of a single magnet of more thansix times the dimensions and at the same time six shocks or currents were generated during a single revolution of the axis so that when aided by a multiplying motion applied to the axis a very rapid succession of powerful currents was produced. A single large magnet with a rotating armature could not be made to produce the same succession of currents without the application of considerable mechanical power.Another peculiarity of this apparatus was that the coils were stationary and the sofi iron armatures alone were in motion by this disposition the circuit was never broken during the action of the machine. In the usual magneto-electric machines with rotating armatures the circuit is necessarily broken twice during every revolution; and this frequently gives rise to irregularities in the production of the currents. By the construction adopted the currents can never fail to traverse the circuit. By means of this apparatus twenty-five charges were frequently fired in divided circuit with such rapidity that the effect on the ear was as of one explosion only of slightly longer duration than when the large magnet -vp.asemployed.On some occasions when a slight difference was made in the velocity with which the apparatus was worked an interval could be distinctly noted between the first and last discharge but even in those instances the effect could not be considered as otherwise than a practically simultaneous discharge. Some sets of fifty charges in divided circuit were also ignited by means of $his appa-ratus; but in those instances the interval between the first and the last discharge was naturally longer being about the same as that observed when twenty-five charges were fired by means of the small magnet above referred to. The system of firing charges by means of magneto-electricity with the aid of the phosphide of copper fuze having been thus far successfully developed a series of experiments was instituted at Chatham for the purpose of thoroughly testing its certainty and applicability in the field and subsequently for ascertaining the extent to which it admitted of application to the explosion of sub- marine charges.These experiments extended over a period of six months and were performed under various conditions of weather 190 ABET ON RECENT hPPLfCATlOXS OF It will readily be ixriderstood that the best and most simple method of connecting the fuzes enclosed in the charges with the sranch-wires and the earth of arranging the experimental charges ?or explosion and of carrying out the various small but essential details involved in the operations were only gradually arrived at; and that consequently in many of the first experiments mliich were only partially successful the fidures were traced to causes uncon- nected with the efficiency of tlie magneto-electric apparatus or the fuze.It would be superfluous in this memoir to enter into details with regard to those preliminary experiments however important they were at the period of the investigation ; the description of the operations at Chatham will therefore he confined to those which mere carried on according to the plan which was ultimately proved to be most efficient. The magneto-electric apparatus employed in all the field experiments was Rfr. Wheat stone’s arrangement of six small magnets just now described the vhole apparatus having been enclosed in a box so that the only exposed portions were the binding screws for the attachment of the wires a handle for setting the armatures in motion arid a key by the dcprcssion of wliich at a given signal the circuit could be completed.To employ the instrument at any moment orilg the following opeiations were necessary ; the insulated wire and the copper wire passing to the earth mere fixed to the apparatus by means of binding screws the instrument was raised from the ground by being placed on its packing case; at that height tt man could operate with it when in a kneeling posture. At the signal ‘‘Ready,” the handle wits turned with one hand so as to cause the armatures to revolve with the greatest possible velocity whilst the other hand was pressed against one corner of the instrument close to the key so as to steady the bax and to be rcady at the signal ‘‘Fire,” to depress the key with the thumb.The connection of the instrument with the earth was effected as follows a moderately clean spade was selected from among those used by the men in digging holes for the charges. One end of a piece of stout copper wire was plnced under the edge of the spade so that when the latter was firmly forced into the ground tlie wire was pressed by the earth on both sides against the iron surface. The protruding wire was mound once or twice round the bottom of the spade handle and then attached to the binding screw of the magnet. The gutta-pzrcha-covered wire used in the experiments having ELECTRICITY TO THE EXPLOSION OF GUNPOWDER.191 been in occasional service at Chatham for some years the coating had sustained some injury in two or three places. Such defects mere protected from possible contact with the earth by means of waterproof cloth or sheet india-rubber. The total length of wire used was 881 yards of which 600 were extended lying along the ground. To the extremity of the covered wire a number (from 12 to 25) of pieces of similar insulated wire varying in length between three and six yards and serving to connect it with the individual charges were attached in the following manner ; about six inches of the extremity of the main wire and of each of the branch wires were laid bare and cleansed; the end of the former was then surrounded with those of the latter (placed in an opposite direction) and the whole tightly twisted together by means of pliers so as to be brought thoroughly in contact with each other and with the main wire.The twisted wires were then bound round with moderately fine copper wire which was made to bring every portion of the exterior of the bundle into connection. The joint was made rigid with pieces of stick tied against it and the whole securely enveloped in a piece of waterproof cloth or canvas to protect it from damp and contact with the earth. These connections though of a very rough description and most readily prepared by any soldier were thoroughly effectual No instance occurred iii the whole of the experiments of the failure of a charge which could be attributed to an imperfect connection of its branch wire with the main wire The following was the method adopted for connecting the fuzes with their respective branch wires and with the earth.The fuzes as they were manufactured were always fitted with two pieces of covered wire twisted together (Fig. 7) which were tightly fixed into their proper positions by forcing a short pin of copper wire into the holes of the fuze-head. They were thus ready for insertion into the bag or other receptacle containing the charge Fig. 7. of gunpowder the ends of the covered wires protruding from the opening of the latter to a convenient distance for effecting the ABEL ON RECEXT APPLICATIONS OF junction with the branch- and earth-wires. The extremities of one of the fuze-wires and of a branch wire (from both of which the gutta-percha was removed to a distance of about t\.lio inches) were connected by hooking them firmly one in the other with pliers (in Fig.8. the manner shown in Fig. 8). A piece of fine copper binding wire was then twisted over the whole of the connection and the joint was finally eiiclosed in a small wrapping of oiled canvas in a manner similar to that adopted at the principal junction with the main mire. The extremity of the other fuze-wire was attached to an un-covered copper wire of sufficient length to bring the whole of the charges into connection with each other in this manner. The wire was fixed in a convenient position by being tnisted round short stakes or pickets driven into the ground and its extremities mere buried in the earth being attached either to spades as already described or to zinc plates about eiglit inches square.The very rapid and comparatively rough manner in which these various connections were made (the tedious operation of brightening cvery metallic connection RO essential with the employment of the voltaic battery being dispensed with) and their universally efficient character were particularly commended by the officers and men who witnessed and assisted in the experiments. With reference to the earth-connections the employment of large metallic surfaces was proved by repeated experiments at Chathain axid Woolwicli to be superfluous. The simple insertion into the ground of the uncovered extremity of the fuze-wires mas found to afford a perfectly sufficient connection for ensuring the ignition of charges.The plan above described of connecting together the whole of the charges was however adopted as being undoubtedly the mode of proceeding least liable to accidental derangement. The largest number of charges which it mas attempted to fire at Once at Chatham was twenty-five. The ignition of twelve charges was repeatedly effected arid nith such rapidity as to have the practical effect of a simultaneous discharge of the whole. With twenty-five charges the interval between the first and last discharge was very decided; it was considered however that eveu ELECTltICITY TO THE EXPLOSION OF GUNPOWDER. 193 the ignition of the twentyfive charges (at a distance of 600 yards from the magnet and with the employment of 881 yards of covered wire and in addition about 100 yards in the form of branch-wires) was effected with sufficient rapidity to allow of that number being employed in cases where a simultaneous discharge was required.It need scarcely be stated that in dealing with electricity of induction defects in the insulation of the main and branch wires had to be very carefully guarded against. Several failures in the first experiments were eventually traced to some defect of that kind. An instance even occurred before the proper method of protecting the connections of the charges with the insulated wires was adopted in which the deposition of moisture upon the gutta- percha-covered wire near the charge prevented the ignition of the latter by forming a connecting link between the extremity of this wire where it was exposed and attached to the fuze and the uncovered wire leading to the earth in consequence of the two wires being in contact at a distance of several inches from the fuze.It is therefore always a preliminary precaution of primary importance that the insulating covering of the wire to be em- ployed be carefully inspected while the latter is being laid out for use and that any imperfections be protected from possible contact with the earth or from the access of moisture; a result easily attainable by the application of some waterproof envelope to the injured portion. The experiments instituted at Chatham with the object of applying the magneto-electric current to the ignition of submarine charges were attended with greater difficulties than those which served to test the system in its application to land-operations; nevertheless the results ultimately attained were also of a character to lead to definite and favourable conclusions.The method of establishing the connections of a charge with the wire and the earth differed naturally in some respects from the mode of proceeding already described. The charges of powder were contained in canisters of block tin carefully soldered so as to JJe watertight.* The fuze with two wires attached as before the one a few inches longer than the other was inserted into the charge and fixed in its proper position in the canister by means of a * Any vessels of this material such as turpentine cans may he employed provided they be perfectly coated inxide with marine glue or some other description of varnish.AREL ON RECENT APPLICATION8 OF loose fitting bung (see Fig. 9) pushed a little distance into the neck and cut out on one side Fig. 9. so as to admit of the passage of the longer insulated wire while the bare part of the shorter wire was firmly pressed by the cork against the inside of the neck. The latter was then completely filled up with melted gutta-percha and the extremity of the short un-corered wire mas bent back over its side so as to be in close contact with the metal surface. In this manner the enclosed fuze was brought into good metallic connection with the wet earth or water by which the canister was sur-rounded.The insulated wire project- ing from the mouth of the canister was connected with one of thc branch wires in the manner already described ; but in order thoroughly to protect the connection from the water in which it would become immersed a piece of vul-canized India-rubber tubing of suitable length and a tin- tube rather longer and wider than the latter were slipped on to the branch-wire before it was joined to the fuze-wire and when the junction had been effected the India-rubber tube was pulled over it and tied very firmly at Fig. 10. both ends on to the gutta-percha covering of the wires. (Fig. 10). ELECTRICITY TO THE EXPLOSION OF GUIUPOWDER.195 A small quantity of a cement (consisting of bees-wax and tur-pentine) was rubbed in between the latter and the ends of the India-rubber tube so as thoroughly to ensure the exclusion of water and finally the tin-tube was pulled over the joint and fixed (by compressing the ends) for the purpose of imparting rigidity to the junction and thus protecting it from injury by any sudden twist or strain. By these arrangements when carried out with moderate care the perfect exclusion of water from the charge and from its connection with the branch wire was effected. The first trials or" these charges were made in a shallow canal with a mud bottom and from which at the time of experiment the water was receding so rapidly that before the whole of the charges had been immersed several of them were exposed to view being partly imbedded in the mud.Twenty-five charges were arranged of which thirteen were exploded though less rapidly than in the experiments on land. On the next occasion when twenty-five charges were entirely surrounded by water (simply resting upon the firm bed of a pond of some depth) only four of the charges were exploded. Several other attempts were made to fire a smaller number of (ten and five) charges similarly immersed but in every instance only four were ignited. A careful examination into the cause of the invariable explosion of so comparatively limited a number of charges under water led tc! the following explanation It will be remembered that the explosion of numerous charges in a divided circuit by the magneto-electric apparatus with revolving armatures is effccted by the action of au exceedingly rapid succession of currents.The rapidity with which they follow each other however great cannot eqnal that with which the terminals of a fuze enclosed in a small charge under water come into contact with the latter after the explosion. The instant this occurs a complete circuit is established through the water and any further action of the current is at once arrested. By the time therefore that four charges had been ignited in extremely rapid succession so as to be apparently exploded at once a suffi-cient interval of time had in reality elapsed to allow the water to re-occupy the space filled for a brief period by the gaseous pro- ducts of the first explosion and thus to rush in iipon and complete the circuit with the terminals of the fuze.It appears probable that with the employnient of' larger charges of powder (about eight ounces was the quantity exploded in each charge) when the 196 ABEL ON RECENT APPLICATIONS OF volume of water displaced by the explosion would be more con- siderable a great number of charges would be exploded before the circuit could be completed by the water. No opportunity occurred during the experiments of ascertaining this by actual trial. The instances however in which it is indispensably necessary that a number of charges should be exploded together suspended in water or simply resting on the ground below and being in immediate contact on almost all sides with water appear to be of exceptional occurrence.Submarine charges are generally so arranged as to be partially or completely surrounded by the objects upon which the force of the exploding charge is to be exerted and they are even frequently firmly fixed in their position by being partly or wholly embedded in sand mud or some similar material. In such cases the resistance to be overcome by the explosion is greater than if under conditions otherwise similar the charges were simply in direct contact with the water and hence the interval is increased which must elapse before the water Cali complete the circuit. The results of some experiments made at Chatham appear to show that under such circumstances the number of charges ignited at one time by the magtieto-electric apparatus must be greater than if they were simply immersed in water.One experiment has already been mentioned in which thirteen charges out of twenty- five were exploded at one time most of them being imbedded in mud. On another occasion ten charges were placed in small pits filled with water the canisters being covered in with mud beneath the latter. Nine of the charges were fired; the branch wire of the tenth was accidentally severed at the moment of the explo- sion from its lying across one of the pits. A careful consideration of the results furnished by these and other similar experiments on the application of magneto-elec-tricity to the explosion of charges led to the following conclusions The explosion of a single charge of powder by means of the phosphide of copper fuze and a magneto-electric apparatus (even of the smallest size generally manufactured) is absolutely certain.With the employment of a magneto-electric apparatus similar to that used in the Chatham experiments and termed by Mr. Wheatstone the <(magnetic exploder,” the ignition at one time of fuzes varying in number from two to twenty-five is certain provided these fuzes are arranged in the branches of a divided ELECTRICITY TO THE EXPLOSION OF GUNPOWDER. 197 circuit in the manner described. To attain this result it ia only necessary to employ a single wire insulated by a coating of gutta- percha or India-rubber and simple metallic connections of the apparatus and the charge with the earth.The explosion of from twelve to twenty-five charges may be effected in the above manner at a distance of at least 600 yards from the apparatus with a rapidity which in its results will in all probability have the practical effect of a simultaneous discharge This statement refers only ho charges on land. The number of submarine charges which can be exploded with certainty at one time by means of the magnetic exploder appears more limited; but if such charges are entirely or partially embedded in sand mud or other dense materials from two to ten may be fired with certainty. By the employment of separate wires leading from the instrument to each charge or by adopting a rheotomic arrangement for effecting the discharge there is little doubt however that the results obtained with the magnetic exploder in submarine opera- tions would be quite equal to those definitely established in the ignition of charges on land.The only precaution to which it is necessary to attend in order to ensure uniform success in the application of the magnet are the proper insulation throughout of the main wire and branch wires leading from the instrument to the charges and the thorough protection of' all connections of wires from the access of moisture. The system of firing charges by magneto-electricity .possesses important advantages over the application of the voltaic battery to that purpose the principal of which are as follows The magnetic exploder is at any time ready for immediate employment; it is easily transported by hand being of small dimensions and weight; it is not liable to injury or derangement provided the most ordinary care be applied to its preservation and transport; it may be employed for many years without suffering any important diminution of its power ; and as all arrangements in connection with the instrument are mechanical any injury which they may sustain can be repaired by ordinary workmen.The magnet-fuze is more certain than any fuze-arrangement applied with the voltaic battery and as safe as any arrangement employed for igniting gunpowder by friction or percussion. It may be preserved for a great length of time in any climate and will bear very rough treatment without chance of injury.The implements and materials required for carrying on opera- 198 ABEL ON RECENT APPLICATIONS OF ELECTRICITY ETC. tions with the magnet in addition to the instrument the wire aikd the fuzes are very few in number inexpcnsive and easily replace- able; they occupy but little space and require no more care in their transport than ordinary artisan's tools. All the operations necessary in the employment of the magnet (the connection of the fuzes with the instrument their introduction into the charges and the explosion of these) are of the simplest possible character and can therefore be performed by any person of ordinary intelligence. It can be confidently affirmed that the general certainty of the magneto-electric arrangement is decidedly greater than that of voltaic batteries and that the necessity of ensuring a proper insulation of wires and connections though it may be regarded in the light of a difficulty by those accustomed to carry on operatians with the voltaic current is in reality a condition which may be fulfilled readily and with certainty by the use of very simple means and precautions.There is little question that with battery-power of great rnagni- tude and with the successful fulfilment of' the numerous indis-pensable conditions and precautions (which long experience has shown to be involved in considerable uncertainty) it is possible to fire at one time a very much larger number of charges than those which have been quoted as the greatest task to be accomplished with certainty by the apparatus proposed for general use.It has however been stated by high military authorities on these subjects that the instances in which it is required to fire more than from twelve to twenty charges at one time are quite exceptional and that indeed twelve may be considered as the greatest number of' charges which it may be necessary to apply in all general opera- tions. In special cases such as the destruction of very massive works where it would be advantageous to apply the force of exploding gunpowder simultaneously to a very large number of different places the employment of arrangements of a special character is always admissible. In such circumstances there is no question that a powerful induction coil-machine with the employment of very moderate battery-power and of the new fuzes would furnish with certainty results of as great a magnitude as could be desired and that its use would be less likely to be attended with diffculties than that of the hydro-electric or plate electric machine.For all operations of a general character however the results CALVERT ON A CARBONACEOUS SUBSTANCE IN CAST IILON. 199 obtained up to the present time have satisfactorily proved that the system of exploding charges in the form of mines for the simultaneous or regularly successive discharge of guns at a con-siderable distance or for any similar purpose by a magneto-electric current is in point of certainty and simplicity superior to any other which has hitherto received application

ISSN:1743-6893    

DOI:10.1039/QJ8621400165

出版商:RSC    

年代:1862

数据来源: RSC

摘要:

CALVERT ON A CARBONACEOUS SUBSTANCE IN CAST IILON. 199 XTr1.-On the Composition of u Carbonaceous Substance existing in Grey Cast Iron. BY F. CRACECALVERT,F.R.S. F.C.S. HAVING: often noticed that the quantity of carbonaceous mass left in the vessels in which grey cast iron was dissolved varied with the concentration of the acid used I began in September 1858 a series of experiments on the action of very weak acids on cast iron in the hope of obtaining a quantity of the so-called graphite which it contains and I believe that I have arrived at results which throw much light upon the chemical composition of this substance proving it to be composed of iron carbon nitrogen aud silicium. This substance occupies exactly the same volume as the cast iron from which it is obtained and is sufficiently soft to be easily penetrated by a blade.I shall now describe the method of experimenting. Cubes of one centimetre in dimension of Staffordshire cold- blast cast iron were placed in corked bottles with eighty times their volume of the following weak acid solutions :-Sulphuric acid 1 alkalimeter 10 grains of SO anhydrous. Nitric ?? 1 >> 13.5 ,, % 9.12 , HC1 >J yJ Hydrochloric 1 , d .M a Acetic + 12-75 C,H,O, E 1 ,> 99 >, 9) Oxalic >> 1 > 9.00 c,o, JJ Y Tartaric , 1 , 0 33.00 > C8H4OI0,, ~ Gallic 1 1 J> \10*00 , cryst acid. 200 CALVERT ON COMPOSITION OF CARBONACEOUS The foregoing figures represent the equivalent quantity of anhydrous acid as compared with 10 grains of anhydrous sulphuric acid per alkalimeter.Besides the above phosphoric carbonic oleic acid tannin and acid peat-water were also used. After three months of contact I found that although the external appearance of the cubes was nct changed in any of the vessels still those in contact with the weak sulphuric hydrochloric and acetic acid solutions especially the latter had become so soft externally that the blade could penetrate threc or four rnillimetres into the cubes. I therefore removed the solutions from the vessels and replaced them by an equal bulk of each weak acid solution and continued to do so every month for two years. I then found that the cubes in contact with the acetic acid ceased to yield iron to the acid although they were still of the original size; they had therefore become transformed into the carbonaceous substance before mentioned.These are the results of the action of the various weak acid solutions on the centiinetre cubes of grey cast iron after two years :-Acetic acid . Complete. Hydrochloric acid Nearly complete. Sulphuric acid . Ditto ditto. Nitric acid . . Action less complete than above. Phosphoric acid . No similar action. Oxalic acid . . Ditto. Tartaric acid. . Ditto. Tannin . . Very slight action. Carbonic acid . Ditto. Gallic acid . . Ditto. Oleic acid . . Ditto. Acid peat-water . No similar action. The action of acetic acid on grey cast iron is most interesting; for instead of ceasing when saturated with oxide of iron as is the case with other acids its action is continuous if the precaution is taken to close the mouth of the vessel with an ordinary cork.Thus I have had cubes of cast iron in contact with the same quantity of acetic acid for two years and the chemical action still existed when the contents of the botties were examined. This action of acetic acid appears therefore to be analogous to that which it has on lead. SUBSTANCE EXISTING IN GREY CAST IRON. To examine the chemical composition of the cubes transformed by the action of acetic acid they were reduced to fine powder in an agate mortar and well washed with boiled water slightly acidulated with acetic acid. The polvder was then dried at 115O C. in a dry atmosphere of carbonic acid or hydrogen according to the nature of the body to be determined in the mass.The carbonaceous substance so prepared presented the following properties and composition :-The cubes of grey cast iron which originally weighed 15.324 grammes weighed only 3.489 at the end of the two years and their specific gTavity was reduced from 7.858 to 2.751. Their com-position was as follows :-Composit on of the Composition of the original cubes. carbonaceoussubstance. Iron . . 95.413 79,960 Carbon . 2.900 f 1-020 Nitrogen . 0-790 2.590 Silicium 0.478 6,070 Phosphorus 0.132 0.059 Sulphur . 0.179 0.096 Lost . 0.108 0*205 .___--100~000 100*ooo These results lead to the following remarks :-Nitrogen.-That the largest part of the nitrogen originally existing in the cast iron remains in the graphitoid substance and only a small portion is transformed into ammonia.These facts tend to prove that the nitrogen of cast iron exists in it under two states namely that one portion is combined with the carbon whilst the other is in a coadition to unite with the hydrogen liberated from the water and thus to form ammonia. This method of ascer-taining the amount of nitrogen in cast iron by determining the quaxititg of nitrogen in the state of ammonia and that existing in the carbonaceous mass appears to be the best process known for I obtained 0.790 from the same cast iron which only yielded me 0-100 by the process lately published by M. Fremy. For ordinary analyses of cast iron the slow action of acetic acid may be advantageously replaced by that of hydrochloric acid taking care to use freshly distilled acid water free from ammonia and placing the whole in a flask provided with cork VOL XIV.P 202 CALVERT ON THE COISIPOSITION OF A CARBONACEOUS and tube so a9 to exclude the possibility of the ammonia existing in the atmosphere from interfering with the experiment. By this means the amount of nitrogen existing in cast iron can be easily and speedily ascertained. XiZicium.-T have ascertained by direct experiments that it is silicium and not silica that enters into the composition of the carbonaceous mass. Amongst other experiments I may state that I took 5.96 grains of the carbonaceous substance dried at 115"C.in a current of carbonic acid and after hwing placed it in a small platinum dish the whole was introduced into a porcelain tube and submitted for several hours at a red heat to a current of pure and dry oxygen. I then found that the 5.96 grains had increased to 7.39 grains or nearly the theoretical amount for 596 grains of substance mould lose 0.664 of carbon and the remaining 0,338 of siliciurn would become 0.718 of silica whilst the 4,692of iron would become 6.702 of peroxide of iron or both added together 7.420 being within 0.13 grain of the weight actually found. Now if the iron in the mass had been in the state of protoside and the silicium in the state of silica the 5.96 grains employed would after the loss of carbon have decreased to 5.551 grains leaving therefore no doubt that the carbonaceous substance contained metallic iron and silicium.Finding however that the quantity of silicium in the carbonaceous substance though high did not represent the whole of the silicium contained in the cast iron employed I passed the hydrogen liberated by the action of weak acids on cast iron through fuming nitric acid and found on the evaporation of this acid a white deposit of silica. All acids which give off hydrogen when in contact with cast iron also give rise to the gas discovered by Wohl er namely silicide of hydrogen. Carbon.-Like silicium the quantity of carbon found in the carbonaceous compound does not represent the whole of the carbon pre-existing in the cast iron employed as carburetted hydrogens are given off during the slow action of acetic acid on cast iron.* Iron.-As shown by the above analysis the carbonaceous com- pound contains 79.960 of mctallic iron even when the acetic acid has ceased to act upon it.I have made several experiments to satisfy my mind that the carbonaceous mass contains metallic iron and not oxide of iron. Thus I passed hydrogen at a dull-red heat * I am now engaged in prepttiing a sclmcicnt quantity of these hydrocarbons to cuablo me to submit them to a careful examination. SUBSTANCE EXISTING IN GREY CAST IRON. 203 over some of the carbonaceous substance previously dried at llSo and obtained no water and the experiment related under the head of silicium confirms this conclusion.All grey cast iron8 appear to yield the same relative proportions of carbon and iron; but as cast iron becomes harder and whiter the amount of carbon decreases and in fact nearly disappears in Velsh white cinder iron beiug replaced by silicium. The relative amount of carbon and iron in the carboiiaceous substance corresponds to 4C and 6Fe or are the same that I have found in some cast iron which had been saturated with carbon by melting No. 1cast iron in presence of a large excess of coke on a cupola and called techni- cally '' keechy." I do not however believe that the carbonaceous substance obtained by me is simply composed of 4C and 6Fe but that the nitrogen and silicium found in it must likewise enter into its com-position. But in the present state of "9 researches it ~ d d be premature to attempt t.3 assign any definite composition to this substance As I am however still pursuing the subject I shall be happy if I arrive at any conclusion to communicate the same to the Society.When the graphitoid substance prepared by the above process is exposed to the atmosphere it absorbs oxygen with rapidity and the temperature of the mass rises rapidly protoxide of iron being first formed which is converted into sesqui-oxide ; but when this mass is placed in distilled water a chemical action ensues similar to that described by M. Kuhlmann namely a portion of the carbon is converted into carbonic acid by the oxygen of the sesqui-oxide of iron and the carbonic acid thus produced unites with protoxide of iron to form carbonate of protoxide of iron.The atmospheric action on the carbonaceous substance above described explaias the difference of composition which I have found to exist between the body obtained by me and that of a soft graphitoid mass which was found to replace a mass of iron burled for many years amongst coal cinders and which had the following composition :- 204 CALVERT ON A CARBONACEOUS SUBSTANCE IN CAST IRON. Mean of several Analyses. Peroxide of iron . . 66.61 Carbon . 12.03 Silica . . 78.13 Sulphur . . . 0.79 Phosphorus . . . traces Lime . . 0 . . . 2-14 99-70 Nitrogen was also present but its amount was not determined. I am aware that the latter curious and interesting change in cast iron has been several times noticed.Thus Dr. Henry published a short notice on this subject in the ‘(Annals of Philosophy.” Mr. R. 3’1allet also described a similar substance in the “Transactions of the British Association.” Mr. W arington has also noticed the conversion of cast iron into a soft black sub- stance which occurred in a brewery where it was in contact with sour beer. Lastly Mr. E. W. Binney records in the 1lth volume of the “Memoirs of the Manchester Philosophical Society,” a description of a similar substance found by him at the emptying of a deep coal-pit in whicb the cast iron had remained submerged for a few years and which yielded to Dr. Angus Smith the following composition :-Iron and bases . . . 38.8 Carbon . 40.0 Silica .. . 19.7 -98.5 In conclusion the conversion of the guns of the “Royal Gcorge,” at Spithead is so well known that I merely refer to it to express the same opinion as Mr.Binney,-that it strongly behoves those who have charge of lighthouses now so often erected in the sea upon cast-iron pillars to carefully and frequently inspect such structures for day by day their support must be weakened by the action of the salt-water. (See Memoirs of Manchester Philosophical Society Vol. II. page 28.)

ISSN:1743-6893    

DOI:10.1039/QJ8621400199

出版商:RSC    

年代:1862

数据来源: RSC