摘要:

THE QUARTERLY JOURNAL OF THE CHEMICAL SO CIETY. XVI.-Note on the existence of Strontia in the Well-Waters of Bristo1. BY MESSRS.WILLIAMHERAPATHAND THORNTON J. HERAPATH. Our attention was first directed to this subject in consequence of the discovery of a small quantity of sulphate of strontia in the deposit or crust which had formed in the interior of a pipe in con-nection with the hot baths at our Royal Infirmary. We subse- quently found that this compound was also contained in very minute proportion in the water with which this institution was supplied. Having been much occupied lately in examining the well- waters from different parts of the city and its suburbs we have succeeded in assuring ourselves that the above is not an isolated case and that sulphate of strontia occurs to a greater or smaller extent in the waters from most parts of the city particixlarly in those from the neighbourhood of Cotham Kingsdown and West Clifton as well as on the opposite side of the city at Yyle Hill.The liasic and marly strata which occur here as is well known contain fine beds of crystallized celestine for which this district has been long celebrated. Hence the presence of this mineral ingredient in the water is easily accounted for. Those waters we have found to contain the largest proportion of strontia are obtained from Cotham on the edge of the lias and at its junction with the new red sandstone. In one specimen which we examined from this locality we detected as much as three-tenths of a grain of the sulphate per gallon.The process of analysis pursued VOL. V.-NO. XIX. 0 MR. F. C. CALVEKT in this inquiry was as follows :-The water having been evaporatcd to dryness the residuary mass was heated with an excess of pure sulphuric acid in order to convert the whole of the earthy and alkaline salts present into sulphates and also to get rid of the organic matter. The excess of sulphuric acid was then expelled by a further application of heat and the fixed residue extracted first with boiling water and subsequently with hot hydrochloric acid until the whole of the matters that were soluble in those menstrua were dissolved out. That which remained consisted of a mixture of silica with sulphate of strontia. In order to separate these two substances they were placed in a platinum capsule and exposed to thevapours of hydrofluoric acid by which means the silica was abstracted and sulphate of strontia left behind in the pure state.The necessity for the first operation originated from the fact that the sulphate of strontia is somewhat soluble in chloride of sodium and therefore upon attempting to estimate it without taking the precaution to first con- vert the whole of the bases into sulphatcs a loss would be sustained in consequence of the solution of a part of the sulphate of strontia in the water. We have also discovered extremely minute traces of sulphate of strontia or sulphate of baryta in many well-waters from other localities. At all events the siliceous residue obtained by the above process when fused with a mixture of starch and carbonate of soda yielded a fused mass which upon solution in water and testing with the nitroprusside of potassium produced a faint violet colouration which could only be caused by the presence of a trace of alkaline sulphide resulting from the decomposition of an earthy sulphate insoluble in hydrochloric acid.

ISSN:1743-6893    

DOI:10.1039/QJ8530500193

出版商:RSC    

年代:1853

数据来源: RSC

摘要:

MR. F. C. CALVEKT 194 XVIL-A new method for the analysis of Chrome Ores. BY F. C. CALVERT. It is well known to all chemists who have analysed chrome ores what di%culties they present and what long and tedious rnanipu- lations are required to produce satisfactory results. In the numerous analyses of chrome ores which I have made I have found it im-possible to make two analyses of the same ore satisfactorily corres- pond. I have therefore been led to make a series of experiments the results of which I have now the honour of laying before the Society. By the results I have obtained I believe I have removed ON THE ANALYSIS OF CHROi?fE ORES. 195 the objections inherent in the present mode of attacking the ore the first of which consists in the difficulty of obtaining crucibles capable of resisting for several hours at a high temperature the com- bined actions of nitrate and carbonate of potash but more especially of caustic potash which it is essential to the operator to employ in order to properly attack his ore.Silver crucibles cannot stand the temperature and those of porcelain or platinuni are either dissolved or injured. The second and most serious objection to be raised is that owing to the high specific gravity of the ore it falls to the bottom of the fused mass and thus becomes excluded from the necessary oxidizing action of the atmosphere to transform the oxide of chromium into chromic acid. As the chromic acid is thus produced but very slowly the consequence is the ore is very imperfectly attacked although the calcination be continued for several hours.The first method I have employed with success consists in mixing intimately a given quantity of the well-pulverized ore with about threc or four times its weight of amixture made by slaking quicklime with caustic soda and then drying and calcining the mass. To the inti- mate mixture of soda lime and ore one-fourth part of nitrate of soda is added. The whole is then well calcined for two hours taking great care to stir the pasty mass every quarter of an hour with a platinum wire. In consequence of this mixture not becoming fluid the ore is constantly kept in contact with the oxygen of the atmosphere and thus becomes decomposed and the oxide of chromium oxidized. I find that by this method one treatment is generally sufficient to completely attack the ore.It is seldom that two treatments are necessary whilst by the method usually adopted five or six successive calcinations are required. Henry Rose states that these calcinations may be avoided by weighing the remaining residuum or ore not attacked and then calculating the chrome in it from that which has been acted upon; but this mode would lead to incorrect results for chrome ore always contains silica and alumina which are easily dissolved in the first operation. The greater part of the inass is now dissolved in water and to the insoluble portion sulphuric acid diluted with twice its bulk of water is added. When the whole is removed from the crucible a little alcohol is added to the solution which renders the sulphate of lime nearly insoluble.The whole is next thrown on a filter and washed three or four times with weak alcohol which dissolves all tlie bichro- mate formed leaving the sulphatc of lime with the ore not attacked on the filter. The former is easily removed by washing the filter with 02 MR. F. C CALVERT ON CHROBTE ORES. boiling water. If any ore is left as a residuum it is recalcined. The solution containing the bichromate of soda is now neutralized with ammonia and oxalate of ammonia added which gives rise to a small precipitate of sesquioxicle of iron alumina and oxalate of lime together with a little silica dissolved by the excess of sulphuric acid. The precipitate having been separated and well washed the liquor is either boiled with alcohol to reduce the chromic acid to the state ofoxide to be precipitated and valued ;or the liquor is rendered acid and the amount of chromic acid ascertained by protochloride of tin according to Dr.PennyJs process. The two following analyses of an ore from Turkey were made by this method I. 11. Sesquioxide of chromium . . 57-60 . . 58.40 Protoxide of iron . . . 25.78 . 26.14 Sand clay chalk . . . . 17.50 . . 16.35 Another process which I have found to produce also good results consists in calcining the well-pulverized chrome-ore with nitrate of baryta the oxygen of which as it leaves it gradually oxidizes the oxide of chmmium. From time to time towards the end of the operation a little caustic potash is added which facilitates the action and gives rise to chromate of potash.The transformation of the oxide of chromium into chromic acid is nicely effected by the pasty state of the fused oxide of barium preventing the ore falling to the bottom of the crucible and thus becoming excluded from the oxidizing action of the atmosphere. On cooling the crucible and its contents are put in contact with dilute nitric acid which dissolves the greater portion of the niass leaving the non-attacked ore. This residuum after being washed is ready for a new treatment if deemed necessary The liquor containing the bichromates of soda and baryta nitrate of baryta peroxide of iron alumina and lime is first heated with sul-phate of potash which precipitates the baryta in the state of a sul-phate. The precipitate is thrown on a filter and washed; and to the filtrate ammonia and oxalate of ammonia are added on which peroxide of iron alumina and ovalate of lime fall down. The mixed precipi- tate is gathered on a filter washed and the chromium in the chromate determined.

ISSN:1743-6893    

DOI:10.1039/QJ8530500194

出版商:RSC    

年代:1853

数据来源: RSC

摘要:

MR. P. DUPFY ON TRANSFORNATIONS OF FATS. XVII1.-On certain Isomeric Transformations of Fats. BY PATRICK DUFFY OF THE BIRRBECK LABORATORY UNIVERSITY COLLEGE LONDON. Chevreul gave the name of stearic acid to a particular acid derivable from certain natural fats while at the same time he used the word stearine as a synonyme for the most solid portion of any natural fat which furnished glycerine; thus he speaks of the stearine of human fat while at the same tirne he shows that stearic acid is not derivable from it. Lecanu afterwards prepared from mutton fat a substance which on decomposition by alkalies yielded an acid consisting chiefly of stearic acid and proposed to restrict to this substance the name of stearine. Most chemists adopting the principle of nomenclature con- tained in Lecanu’s proposal now understand the names stearine margarine &c.to signify bodies which if they were obtained would on decomposition by alkali furnish respectively only stearic acid margaric acid &c. and glycerine and in the absence of such sub- stances apply them to those which most nearly approach them. The origin of this nomenclature for the fats belongs however not to Lecanu but to Chevreul ;for throughout his work on the fats stea- rine is the only exception to it. This exception I wish to remark has been rather unfortunate :for many physiologists and some chemists still employing the word in the sense in which Chevreul used it have particularized by it bodies which other chemists have described as margarine or palmitine.This diversity of nomenclature has already introduced many apparent discrepancies into works upon the fats and as a consequence some real difficulties in the way of further investigation. I refer to the circumstance here not because I have any change of name to propose but because I think allusion to it will be suflicient to render obvious the advantages of allowing stearine to signify the substance whether hypothetical or not which on decomposition by alkali affords stearic acid and glycerine instead of forming an exception to a convenient and established system of nomenclature. ChevreuW prepared what he called stearine from five different sources viz. human fat fat of swine fat of the goose mutton fat and beef fat. As he gives instead of the melting point the point of solidification after melting and as other chemists in speaking of the stearine prepared by them have given only the melting point we are * Recherches Chimiques sur les corps gras.Paris 1823 p. 261 &c. restricted to use as the standard of coniparison for their results the melting point of the acid furnished 6n saponification. The acid from the substances prepared by Chevreul even after the removal of a portion of oleic acid melted only in one case so high as 64.8' C. Since the melting point of stearic acid as found by him and confirmed by others (Redtenbacher,* Laurent and Gerhardtj-) is 704 none of the substances which he called stearine can be regarded as a close approximation to pure stearine.BraconnotJ by using essence of turpentine as the purifying agent instead of alcohol which Chevreul used succeeded in pro- curing a substance which melted at 61-25' and furnished an acid fusible at 62.50'. Afterwards Lecanug prepared from mutton-fat by means of ether a substance which melted at 62' and furnished an acid melting at 64'. He states that he found it impossible to raise the melting point of this acid by purification higher than 66O and adds that &I. Bussy in researches which he was then pursuing had not found stearic acid to melt higher than 66'. Hence he concluded that what he called stearine was a pure substance. Since then stearine has been prepared in the same manner by Liebig and Pelouze,ll who do not mention its melting point in their paper; by Artzbiicher,T who brought its melting point to 60*6*,and by Heintz,** who agrees with Lecanu in its melting point.Although these chemists may not concur with Lecanu in regarding any of these substances as pure stearine they yet admit that it is impossible to raise its melting point above 62.25'. There are three ways in which the chemical purity of the glycerine- fats may be estimated-1 st. That further crystallisation produces no change in the melting point of the fat itself; 2nd. That when crystal- liaed the crystallised portion and that remaining in the mother-liquor differ not at all or only slightly in melting point ; 3rd. That on saponification the resulting acid be not susceptible of having its melting point changed or in other words of further purifi- cation.The first of these tests is that by which chemists have hitherto been guided in the purification of fats ; but although competent it * Ann. Ch. Pharm. XXXV 46. Compt. Rend. trav. chim. 1849 p. 337. $ Ann. Chim. XCIII 252. J. Pharm. XXV [2] 307. g J. Pharm. XX 325. Ann. Ch. Phys. LV 192. 11 Ann. Ch. Pharm. XIX 264. J. pr. Chem. 173. Ann. C:i. Pharm. LXX 239. Compt. Rend. trav chim. 1849 p. 343. ** Pogg. Ann. LXXXIV 229. .ISO 31 ERIC TBAXSFORMA TI0S S OF PATS I99 is calculated to deceive unless very delicately applied and as will be seen has really done so. In the treatment of mutton fat by ether for the preparation of stearine I have found that although between two successive crys- tallisations after the fifth the thermometer can scarcely distinguish yet if these two crystallisations be melted under the same circum- stances a difference of time in the commencement of melting will be perceived a difference which is still greater the more widely separated in respect to the number of times two specimens may have been crystal- lised ; and although the thermometer may fail to point out a difference in the melting point of two immediately successive crystallisations yet that long after the melting point of stearine has reached 62O the difference of melting point between substances one of which has been crystallised two or three times oftener than the other is quite sensible to the thermometer.Instead however of relying entirely on this test I took as guide the second one which consists theoretically speaking in carrying on the crystallisation from ether till the portion which remains in the mother-liquor has the same melting point as that crystallised out.I say theoretically speaking for even after thirty-two crystal- lisations the residue in the mother-liquor after removal of a second crop of crystals differed in melting point from the first crop by It might be supposed that instead of the impurities being so per-sistent as this represents them the difference of melting point arose from some decomposition taking place every time the substance was dissolved; but this was not the case for I found the melting point and composition of stearine to remain unchanged after ten weeks' contact and partial solution in ether.Each of the thirty-two crystallisations spoken of was made on an average with a quantity of ether at least fifty times that of the sub- stance dissolved and the mother-liquor was poured off when the temperature fell to 16'. At first the crystals were then washed with warm ether and afterwards strongly pressed by the hands in folds of linen; but as the substance approached to purity this was discon- tinued and the mother-liquor removed by decantation alone. A second and sometimes a third crop of crystals was obtained from the mother-liquor and after being sufficiently purified added to the first crop. In the first five or six crystallisations the quantity of ether employed was not more than from ten to fifteen times the volume of the substance dissolved but towards the end it was increased to upwards of one hundred times the volume.In thismanner not more 3'. or 2' 200 MR. P. DUFFY ON CERTAIN than eight grammes were obtained from two kilogrammes of the crude fat. After thirty-two crystallisations the substance which I obtained melted not at 62' but at least 2*higher and furnished an acid melting at 66O.5. It possessed characters hitherto unsuspected in the class of substances to which stearine belongs. The method of taking the melting point consisted in fusing on a hook at the end of a platinum wire a bead of the substance and sus- pending the wire in a beaker containing water previously boiled to expel air. The temperature of the water in the beaker was regulated by placing the latter on a small sand-bath over a gas-lamp.The perfect contact between the bead and the water ensured the identity of their temperature which was given by a thermometer suspended in the water. The temperature at which a small ring of limpid fat sur- rounding the bead first appeared was taken as the melting point. The melting point of substances which like stearic acid solidify after fusion not in an amorphous but in a crystalline condition is best observed by enclosing them in thin-walled capillary tubes ;for when directly exposed to the contact of the water the latter entering the interstices among the crystals and afterwards remaining suspended in the fused mass gives it an opalescent appearance and renders it difficult to distinguish the true melting point.During the preparation of stearine in the foregoing manner I had occasion to take its melting point at various stages of the purification. Observing that after being melted it did not in harmony with the laws of latent heat always solidify at the same temperature as that at which it melted I made a register of its solidifying point in anumber of cases and found that the solidifying point was in most cases from 12-2O to 12*S0 and never more below the melting point but in a few cases not even 2' below it. These observations were made long before I had brought the stearine to a state of purity; but although made on an impure substance they remained good for the purer substance.It was next observed that these variations of the solidify- ing point were not due to agitation in one case and its absence in another ;in short that in those cases in which the temperatiire fell 12.2' below the melting point before solidification commenced the passage into the solid condition was not precarious; it was impossible to produce it by any mechanical means at a higher temperature. For those specimens then under examination the conditions of these variations were found to be that when the temperature was raised as soon as the temperature fell 1' or 2' below the melting point; but that when insetabove the melting point solidification 2' or1'only ISOMERIC TRANSPORXATIONS OF FATS. the temperature was raised 4' above the melting point solidification could be induced only when the temperature fell l%2O below the melting point.When the stearine which had solidified 12.2' below its melting less opaque indeed almost transparent suggesting the impression that it was melting but whether the temperature remained stationary or rose quickly resumed its opacity. Inasmuch as the precaution of enclosing the fat in dry close tubes made no difference in this phe- nomenon it was concluded to be the effect of temperature alone. In the circumstances of the foregoing experiment where the fat was continuously heated froin below to above the point at which the change presented itself the conditions were in favour of its appearing at the lowest temperature capable of producing it. As it was shewn to be the effect of temperature it appeared probable that if the fat were suddenly submitted to a temperature a few degrees higher but not necessarily so high as the melting point this appearance would present itself with greater intensity.A bead of substance of melting point 63' which was the purest I had at the time was placed in a small glass tube at one side of the part which had been previously drawn out to a capillary diameter; the tube mas plunged the end containing the bead undermost into water at 53.6' ; the air was now sucked out of the other end whereupon the fat passed through the capillary part of the tube which had it not been fluid it was impossible it could do. Hence there remained no doubt whatever that the fat really melted at the temperature at which the foremen- tioned transparency appeared and afterwards solidified at the same or even at a higher temperature.* The question now arose is the stearine the same in every respect after as before this melting? that is has it the same properties and among the rest that of melting at this lower temperature? When taken after melting and again solidifying at 53*6' and plunged into water at that temperature it did not melt; in short it melted only when the temperature rose to its ordinary melting point 63'.The * Since I finished my experiments on this point my attention has been called to the fact that Dr. Heintz of Halle (Ber. d. Rerl. A. 1849 222. J. pr. Chem. XLVIII 382. L'Instit. 1849 390) had also noticed that stearine from mutton fat melting at 62O-62*25O,became transparent when immersed in water at 51°-52* and afterwards resumed its opacity when the temperature rvse to about 58O.He has however ghen no expla- nation of what takes place but merely stated that the stearine does not become fluid. His reasons for this conclusion consisted in the fact that a thin layer of stearine did not change its form although it became transparent when plunged into water at 52O. In repeating the experiment I have found that whenever the stearine becomes entirely transparent it takes the form that would be assumed by a fused mass of any other substance. above the solidifying point it became 1' point was again heated about MR P. DUFFY ON CERTAIN stearine had therefore by melting and again solidifying at 53*6O passed into a different isomeric modification.The only evident difference between these two modifications is that one melts imme- diately above its solidifying point the other only at 12.2’ above it and that the former approaches slightly more to translucency and is more reflective of light than the latter. Before melting and solidifying at 53*6O the stearine had the pro- perty of melting at that and even at lower temperatures so low that when we take the consequences instead of the actual appearance as evidence we must admit that the proper point for placing the first melting point at is as nearly identical with the point at which it soli-difies after being heated 4’ above its hitherto known melting point as the melting point of any metal is with its solidifying point.What I mean by taking the consequences as evidence is that the appearance of melting at 53.6’ being succeeded by the transition into a modifi- cation which melts only at 63O if we find that this transition is a consequence of keeping it a sufficient length of time at 51° then although we may see no appearance of melting we must consider that it does melt at that temperature. In the case of this specimen which melted at 63O and solidified about 50.5’ it was found that although a temperature of 51’ required a long time to produce the change into the modification melting at 63O it was yet sufficient to do so and for that reason I conclude that the first melting point is at least within 0.5’ of the solidifying point.A reason why this transition at the lowest sufficient temperature is not preceded by the appearance of melting consists in the fact “that next to water fat possesses the greatest capacity for heat;”* and “is also one of the worst conductors of heat when fluid;”? so that after the heat of the water in the experiment has melted the surface of the bead the surface or say the superficial stratum will have again solidified in the modified state before the heat has penetrated to the next interior stratum; hence at the lowest temperature sufficient to produce the change a portion is always in one or other solid state and at no one moment is the whole transparent but only different portions in suc- cessive moments. It will be readily perceived that the temperature of the first melting point is dependent on that of the solidifying point (the solidifying point after heating 4’ above the second melting point).As all temperatures above the solidifyingpoint and below the second melting point produce the modification of higher melting point if the * Lehmann’s Phys. Ch. translated for Cavendish SOC. by Day I 261. t la. p. 260. ISOMERIC TRANSFORMATIONS OF FATS. solidifying point was higher than it is the first melting point must also have been higher or it could not have existed at all. It yet remained to be found what was the cause that when the temperature had not been raised 4' above the second melting point solidification set in before the temperature fell 12.2' below this melting point.This depended on the fact that there was yet another melting point and another isomeric conditioii corresponding to it. When the temperature was raised only 1' 2' or above the second melting point and then allowed to fall slowly 1' or 2O below it solidification commenced and proceeded not suddenly as at the ordinary solidifying point but slowly and when complete the appear- ance of the fat was entirely different from what it had been in either of the foregoing modifications it was more opaque and friable and melted only at 66*5' or 3.5' above its ordinarily known melting point. To distinguish these different modifications they will be called in the order of their melting points the first second and third; that melting at 51' the first modification; that melting at 63' the second; that melting at 66*5O the third.The latter may be also called the crystalline condition for it really is so; and what is very remarkable as well from its connexion with the other facts in this paper as from its having so long escaped observation the crystals from ether have the third melting point only. From what has been said it will be observed that both the second and third modifications are producible in the interval between the first and second melting points; the second modification in the lower extremity of this interval the third in the higher. There is however no particular point in this interval forming a marked boundary by which the two ranges of temperature that produce the two digerent modifications are separated.In the case of the specimen taken for illustration and having its melting points respectively at 51' 63' and 66*5' the second modification was alone producible under 56' at least within any moderate time; at 56.5' a mixture seemed to be the result whilst at 57' and all temperatures between that and the third melting point the third modification alone was produced. It may also be collected from what has been stated that neither the second nor third modification can be produced from a substance which has been heated to the third melting point; for the liquid which is then formed solidifies only when the temperature falls below the first melting point and is then necessarily in the first modification unless after the lapse of hours.MR. P. DUFFY ON CERTBIN What bas been said of the specimen hitherto spoken of may be summed up by saying that it has threc melting points; it melts at the temperature of the first solidifies ; melts at the temperature of the second solidifies; melts at the temperature of the third and thcn solidifies only when the temperature has fallen below all three; and after solidifying here it may be made to melt again at the first at the second and at the third melting points respectively solidifying as before below all three; and these changes are producible in this succession to any extent without the slightest loss or gain of weight. In specimens where the impurities predominate as those having their second melting point at 61' or below it the third modification is procurable only by obtaining crystals from ether or some other solvent.On the other hand as the stearine approached to purity the appearance of the second melting point snbsided insomuch that when a substance having its first melting point at 52' and its third at at 69O.7 was obtained it did not on being heated continuously from the first to the third melting point become fluid at any intermediate temperature ; however wlien it was melted at or near its first melting point and allowed to solidify at the same temperature and then suddenly removed to a temperature which by inference was judged to be a little above its second meking point as 65O.5 it did melt. At the same time that the second melting point was thus disap- pearing the highest temperature for producing the second modifica- tion instead of rising along with the melting points was approaching more and more nearly to the first melting point thus narrowing the limits for the production of the second modification and extending those of the third so that in the specimen having its first and third melting points at 52' and 69.7' respectively the highest temperature for producing the second modification was about 55' or 3' above the first melting point while in the less pure substance having its first melting point at 51' the corresponding point was 56' or 5' above its first melting point.These facts along with the melting point specific gravity and external appearance" of the second modification being intermediate between those of the other two lead to the inference that if stearine were obtained quite pure the highest temperature at which the second modification would be producible would coincide with the first melt- ing point ; and there being consequently no range of temperature for producing the second modification there would be no second modifi- * Although the appearance is intermediate it is quite distinct.It is described further on. ISOMERIC TRANSFORMATIONS OF FATS. cation and no second melting point but only a first and third melting point or in that case a first and second melting point ; and that what I have called the second modification is a mixture of the other two modifications owing its existence somehow or other to the impuri- ties.But even were we certain that this were the case there would still remain the difficulty of explaining how they could produce it. The following seems to me also a strong reason for believing it not a mixture. In the assumption that it is such is implied that the rela- tive quantities of the first and third modifications in it are such that when the melting point of the former is exceeded its solvent action on the latter is sufficient to make the whole melt some distance below the third melting point Now if this were correct we ought by increasing the proportion of the first modification or in other words of the solvent to be able to depress the melting point of the whole still more. But experiment showed that when a bead of substance having its second melting point at 63' was brought into the second modifi- cation by being melted and allowed to solidify at a little above its first melting point it became limpid at the same temperature 63O as it did when it was allowed to solidify only very partially or when after solidifying the greater part of it was again reduced to the first modification.Dr. Hittorf* has lately shown in an interesting paper on selenium that this substance has two allatropic niodifications and two melting points to correspond ;and that after melting at the higher of the two it solidifies only when the temperature has fallen considerably below both. Now it is also known that selenium softens considerably below what he calls its first melting point; but whether the changes which accompany this softening are those consequent upon a real fusion has not been investigated; but should they be found to be such there would be the closest analogy between its characters and those of stearine.The following is a short table of the melting-point of mutton stearine at different stages of the purification Melting Points. No. of crystallizations. 1 SO^^^^^^ I 1. 1 2. f 3. --------1 5 49O 49.5' 64O z3-3' 17 50*5 51 66.5 32 51.7 52 64*2(?) 69.7 * Pogg. Ann. LXXXIV 214. MR. Pa DUPFY ON CERTAIN rises much more quickly than the first with the removal of the impurities and the third still more quickly than either of the other two. This is explained by what we know to be the general action of solvents; for the influence of the impurities is a solvent one or in other words one which tends to depress the melting point; and for any given quantity of impurities this is greater at the temperature of the higher than of the lower melting point so that this quantity of impurities being removed the higher melting point rises in conse- quence more than the lower.The different modifications have pro-bably also different solubilities even at the same temperature ;indeed the fact of the third modification being always deposited from ether whatever modification may have been dissolved shows that it is the one most insoluble in ether. The property in question should there- fore be ascribed in part to each of these causes. Considering that in general an increase of specific gravity corres- ponds to a loss of latent heat and that doubtless these different modifications of stearine depend on differences of latent heat it became an object to take their specific gravities with as much preci- sion as possible.* The following table showsa decided difference in the density of the different modifications.Where two observations on the same sub- stance at the same temperature are given they were made on different quantities in different bottles as a test of the method. Whatever tem- * As there are other instances where the method employed might be used with some advantage a description of it may be useful. A portion of dry stearine was put into a dry stoppered specific gravity bottle and weighed.The bottle was then filled with distilled water inverted in a beaker containing distilled water and the whole heated to 1000 in this way the fat melted and allowed any adhering air as well as that expelled from the water to collect in a single globule ; after cooling the bottle was taken out of the beaker and being placed in its ordinary standing position the greater part of the globule of air rose into the neck of the bottle whence it was expelled by filling its place with water. To remove the air which still adhered to the fat a tube about two inches long and aide enough to admit the head of the stopper was attached by a piece of vulcanized caoutchouc tubing to the neck of the bottle and filled with distilled water. The temperature of the water being about 30" degrees the apparatus was placed in a beaker under the receiver of the air-pump.On exhaustion the remaining air in the bottle rose by its elastic force through the orifice in the stopper and through the water in the little reservoir. On readmission of the air to the receiver the water in the reservoir mas forced into the bottle to supply the place of the removed air. The bottle being thus filled was after removal of the tube again placed on its side and the orifice immersed in a beaker of distilled water ; by bringing the temperature of the water in the beaker to the required pint that in the bottle was brought to the same and all the different modifications of the fat successively produced. Before taking the bottle out to weigh it it is necessary to keep the temperature a considerable time at the point to which the determination refers otherwise the slow cooling of the fat arising from its great specific heat and bad conducting power will occasion serious errors.ISOMERIC TRANSFORMATIONS OF FATS. perature the determination is referred to water at the same tempera- ture is the unit. SPECIFIC GRAVITIES. 3rd M.P. of Temp. at which Modifications. determination substance. was made. 1. I 2. 1 3. 1 Fluid. -_.--.----__. 65' 15' 0.9872 --66.5 15 0.9877 --15 0.9867 1.0101 1.0178 -15 -1,0179 -69.7 51.5 0.9600 -1.0090 { I 65.5 -0.9931 0.9245 68.2 -0.9746 - 3rd M,P of Temp. at which Modifications. substance. determination was made. -1. 2. 3.---Fluid. I_ I 65' 15' 1.0129 -6695 15 1.0124 -- 15 1.0134 0.9900 0.9825 -15 -0.9824 -69.7 51.5 l*0416 -0.9910 -65.5 -1.0069 1.0816 68.2 -1.0260 - c_ 208 MR. P. DUFPY ON CERTAIN by the more convenient and exact method of a volumenometer would point out some interesting relations. None of these modifications conduct electricity. When a small portion of any of them formed part of the circuit of a very intense current produced by a powerful induced magnet with three Daniell's cells the galvanometer was not sensibly deflected. Not the least interesting fact however is that this property of existing in three modifications is not peculiar to stearine from mutton fat; it is possessed by many other fats.At the same time that I prepared steariiie from mutton fat I also sought it in beef fat with the view of submitting to investigation the question of the constitution of the glycerine fats in general as regards their products on saponification by a method proposed to me by Dr. Williamson. The results of this inrestigation are reserved for a future communication. Artzbacher* seems the only chemist besides Chevreul who has attempted to prepare stearine from beef fat. The stearine obtained by him from it melted at 60.6'. Commeiicing with the same quantity of it as of the mutton fat viz. two kilogrammes I obtained after eighteen crystallisations from ether not more than a gramme of substance melting at 63O; the quantity being now so small it was useless to pursue the purification further although the melting point of the residue in the niother-liquor after removal of a second crop of crystals was 2.8' below that of the first crop.It possessed however all the properties of mutton stearine of the same degree of purity so that 63' was only its second melting point. A substance which is probaMy a vegetable tallow but of whose his- tory I know little has also been the subject of investigation. In its crude state it is of a pale yellow cheese-like appearance somewhat motley from parts of it being crystalline and others waxy; it has a slightly disagreeable smell. On saponification it yields a dirty white soap which forms a brown solution and on decomposition by strong acid liberates an acid of a deep brown colour.After one crystallisation of this substance from alcohol and five from ether there remained a glycerine fat which melted only 1.2' higher than the residue in the mother-liquor so that it isnot difficult to purify. Its properties were then analogous to those of stearine but like the purer stearine it does not on being heated continuously from its first to its third melting point viz. from 45.6' to 64*5' melt at any intermediate temperature but when the temperature comes to 62O its appearance quickly changes from waxy to crystalline ; * Ann. Ch. Phami. LXXX 239. Compt. Rend. trav. chim. 1849 343. ISOXERIC TRANSFORMATION OF FATS. 209 this and the results of some experiments similar to those by which the existence of the second modification was shown in stearine after its second melting point had disappeared make me believe that this substance really has a second melting point at 62'.After melting at the third melting point it solidifies in less time than does stearine above the first melting point; so that in order to bring it into the first modification it must be cooled somewhat quickly in less than an hour at most; but at whatever temperature it solidifies it has the same properties as if it had been melted as well as solidified at that temperature This is universally the case ;the properties of the solid fat are regulated by the temperature at its own formation not by that at which the antecedent liquid may have been formed The corresponding modifications of this substance of mutton-stearine and of beef-stearine have the same appearance under the microscope.There is not much to be said of the first modification unless that it appears as mamillz radiated like hematite; when watched under the microscope these mamilla are seen to form suddenly when the tem- perature falls to the solidifying point ;tkg second modification has an exfoliated appearance somewhat suggestive of incipient crystallisation ; the third is perfectly crystalline and by proper attention particularly in the case of the vegetable fat the crystals can be obtained in the dry way as definite in form as from ether but smaller. So far as the eye can judge without means of measurement the crystals of these three substances seem isomorphous but I regret I have not been able to measure their angles.Palmitine from palm oil after twelve or thirteen crystallisations from ether margarine from butter and also margarine from human fat OP at least the more solid portion of that substance after two crystallisations from alcohol and one from ether exhibited similar phenomena with respect to variety of modification and melting point. On the other hand neither elaidine cocinine nor any other of the substances in the subjoined table has the property of existing in more than one modification. In seeking for some feature in the constitution of the substances ghat have this property which would separate them from those that have not the attention is arrested by the fact that most of the sub- stances which possess it as stearine palmitine margarine are unques- tionably the glycerine-fats corresponding to certain members of the series of acids of the formula (GH), O, while among those substances which do not possess it there is not one unless we except cocinine which has such a constitution.In reference to cocinine I may VOL. V.-NO. XIX. P 210 MR. GEORGE Fs ANSELL ON THE observe that although St. Ewe's* analysis of cocinic acid agrees with the formula C, H2 04,yet he as well as Bromcist describe it as destitute of one character cry stallisation and opacity on cooling which so far as is known belongs to every other member of the series of acids to which his formula assigns it. In the following table instead of the formula of the fats themselves are written those of the acids derivable from them; for as yet con- siderable doubt must exist as to those of the fats.In the other cases the formulze of the substances themselves are written. Mutton-stearine . . . 51.7' 52*O064.2'I Beef-stearine . . 50-5 51.0 68.0 Substance from vegetable talloR 45.0 45.6 62.0 Palmitine from palm oil . . 45.5 46.0 61.7 Margarine from butter . 40.0 40.5 51.0 Margarine (P) from human fat. 43.5 44.2 54.5 'I) c__1 Cocinine . . . . . 29.3 133.5 I Elaidinef . . . . 28.0 23*7 38.0 Stearicacid . . . . 65.8 68.0 Palmitic acid . . . . . 59.0 61.0 Margaric acid from butter . . 50.5 52.3 Stearic ether . . . . . 33.0 33.7 Cerotic ether$ . . . . . 60.0 60.3 Cerotin (alcohol) .. . . . 81.0 81.0 Cerotene . . . . . . 57.0 57.8' Chinese wax . . . . . 805 81.0 ParaEn . . . . . 43.5 43.5

ISSN:1743-6893    

DOI:10.1039/QJ8530500197

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年代:1853

数据来源: RSC

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MR. GEORGE F. ANSELL ON THE XIX.-On the qualitafiive separation of Arsenic Tin,and Antimony BY GEO. F. ANSELL. Although a great many processes for the purposes mentioned have been suggested processes which in the hands of experienced chemists will invariably give satisfactory results a method is still wanted * Ann. Ch. Phys. [3] XX 91. Ann. Ch. Pharrn. LXIV 341. t Ann. Ch. Pharm.XXXV 277. $ The solidifying point of elaidine is precarious. 4 I am indebted to the kindness of Mr. Brodie for the specimens upon which I operated of the five last-rnentioned substances. SEPARATION OP ARSENIC TIN AND ANTIMONY. 211 sufficiently simple and precise to admit of being used by the beginner in analytical chemistry. At the suggestion and under the direction of Dr.Hofmann I have made a series of experiments upon this sub- ject and now beg to submit the result to the Chemical Society. The precipitates produced by sulphuretted hydrogen are heated with sulphide of ammonium in the usual way and the sulphide of ammo-nium solution reprecipitated with hydrochloric acid and hydrosul- phuric acid. The precipitate thus obtained which may consist of bisulphide of tin pentasulphide of arsenic and pentasulphide of antimony and occa- sionally of the sulphides of gold and platinum is redissolved in nitro- hydrochloric acid and the solution poured into an ordinary apparatus for generating hydrogen gas so arranged as to allow of washing the gas with a dilute solution of acetate of lead which absorbs any hydro- chloric acid or sulphuretted hydrogen and to pass the mixture of antimoniuretted and arseniuretted and free hydrogen into a test-tube half-filled with pure concentrated nitric acid.If the gas be passed moderately slowly the whole of the metallic hydrides are decomposed ;water arsenic acid and antimonic acid being formed. The nitric acid solution obtained after the gaseous mixture has passed for about a quarter of an hour is evaporated; and the residue after being exposed to a tolerable heat upon a sand-bath in order to expel thelast traces of nitric acid-which is an essential condition of success inasmuch as antimonic acid is slightly soluble in water contain- ing nitric acid-contains antimonic acid arsenic acid and arsenious acid. The residue is now exhausted with warm water which takes up all the arsenic and arsenious acid.The aqueous solution when mixed with nitrate of silver and neutralized drop by drop with ammonia yields if arsenic be present a precipitate of arseniate or arsenite of silver. The colour of this precipitate varies to a considerable extent if the quantity of arsenic be considerable it presents the pure red of the arseniate of silver ;but when the quantity of arsenic is minute in proportion to the amount of antimony the heat necessary to expel the last traces of nitric acid reduces part of the arsenic acid to the state of arsenious acid the silver-salt of which imparts a yellow tint to the precipitate produced by nitrate of silver and ammonia This change of colour in the precipitate is an inconvenience but it does not materially affect the value of the method ;since in a carefully con- ducted operation the formation of any precipitate whatever indicates the presence of arsenic.The residue which is left after complete exhaustion with water is antiinonic acid. It is dissolved in the smallest amount of nitro-PZ 212 MR. G. F. ANSELL ON THE SEPARATION OF ARSENIC &C. hydrochloric acid; in the ordinary analysis the quantities are fre-quently so minute that it is advisable to boil filter and all in aqua regia ; the excess of acid is evaporated as far as possible and the remaining solution is mixed with sulphuretted hydrogen water. If a trace of antimony be present the liquid at once 8ssumes an orange-yellow colour and on boiling decidedly orange-yellow flakes are separated.The method was repeatedly tried by myself and by several of my fellow-pupils with mixtures in which either one milligramme of arsenic was associated with ninety-nine milligrammes of antimony or vice vers4 one of antimony with ninety-nine of arsenic. Both arsenic and antimony could be detected without difficulty if the operations were carried out with the necessary precautions. The detection of tin presents no difficulty. The whole of this metal remains in the apparatus for generating hydrogen either in the form of protochloride or in the shape of a finely-divided metallic pre- cipitate. If the quantity of tin is considerable it is sufficient to filter the liquid in the apparatus and to add to the filtrate proto- chloride of mercury.A white precipitate of subchloride of mercury indicates the presence of tin. Should this experiment yield no result the metallic precipitate (tin with a portion of antimony and arsenic) is detached from the plates of zinc and dissolved in hydrochloric acid and the solution tested by protochloride of mercury. It need scarcely be mentioned that both the sulphuric acid and the zinc used in this operation must be perfectly free from arsenic tin and antimony. Note.-This operation is more successful if the nitric acid be kept hot during the time that the gases are passing but this is not by any means necessary.* If antimony be present the nitric acid will soon become opaque and after a few minutes deposit a white precipitate.* Mr. Ansell’s mode of testing which is particularly calculated for small quantities of antimony may be conveniently combined with an additional experiment for arsenic. Incredibly minute quantities of the latter element even in the presence of a very large amount of antimony are readity and infallibty recognized by passing the mixture of antimoniuretted and arseniuretted hydrogen into nitrate of silver. As is well known the whole of the antimony is precipitated in the form of antimonide of silver (Sb Ag,) while every trace of arsenic remains in solution in the form of arsenious acid. On neutraliziiig the liberated nitric acid by ammonia the characteristic yellow arsenite of silver is precipitated. If the gas has been passed for a long time the solution is some- times free from silver. In this case the silver precipitate of course appears only after the addition of a drop of nitrate of silver. The separation of the antimony from the black precipitate which is a mixture of metallic silver and antimonide of silver is attended with difficulties ; and I find it more convenient to use Mr. Ansell’s method for the detection of minute quantities of antimony.-A. W. H.

ISSN:1743-6893    

DOI:10.1039/QJ8530500210

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年代:1853

数据来源: RSC

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MR. 0. B. BUCKTON ON DIPLATOSAMMONIUM. 213 XX.-Observations upon a new series of Double Chlorides containing D~la~osa~m~nium. BY G. B. BUCKTON, F.L.S. The consideration of the action of cyanogen upon diplatosamine communicated on a former occasion has induced me to undertake some experiments with a view to the preparation of that base in com-bination with cyanic acid. In the course of this examination I have been led to the discovery of a new series of double salts which appear to offer some interest. A description of these salts together with some remarks upon chloride of diplatosammonium with chromic acid forms the subject of the present paper. CHLORIDE OF DIPLATOSAMMONIUM AND CHLORIDE OF LEAD. My attention was first directed to the white crystalline precipitate which falls abundantly on mixing concentrated solutions of chloride of diplatosammonium with acetate or nitrate of lead.After washing the mass it was dissolved in boiling water and filtered whilst hot. The substance reappeared on cooling in the form of small quadrilateral plates of a pearly lustre which often were sufficiently thin to reflect the colours of the soap-bubble. When gathered on a filter they appeared as a mass of frosted silver and the dry crystals resembled those of cholesterine. As this substance did not decompose at a heat below 170' C. the portions set apart for analysis were all dried at a temperature between 110' and 120'. I. 0.5948gms.of substance gave 0.5612 , , chloride of silver equal to 0.1388 , , chlorine.11. 0~5308 , , substance gave 0.5006 , , chloride of silver 0-1238 , , chlorine. 111. 0.5700 , , substance gave 05326 , , chloride of silver 0.1317 , , chlorine. IV. 0.6042 , , substance gave 0.2976 , , sulphate of lead equal to 0.2033 , ; lead. The filtrate by ignition gave 0.1974 , , platinum. 214 MR. G. B. BUCRTON ON DOUBLE CHLORIDES V. 0.6648 gms. of substance gave 0.3271 sulphate of lead 0-2235 lead. VP. 0.7586 substance burnt with oxide of copper 0.1456 water equal to 0*0161 hydrogen. VII 0.7530 substance with soda lime gave 1*0820 platino-chloride of ammonium or 0.0678 nitrogen. From which numbers the following per-centages are calculated 2 I. 11. 111. IV. v. VI. VII. Chlorine . 23.34 23.32 23.10 --Lead .--33.48 33.62 -7 Platinum .--32.67 --Hydrogen . ---2.13 -Nitrogen . ---.-9.0 which correspond to the formula ; Pt H N2 C1 . Pb Cl. The theoretical and experimental per-centages are as follows Theory Experimental mean. r-A- Pt . * 99-00 32.X 9 32.67 H6 ' . 6-00 1 *95 8-13 N2 . 28.00 9-10 9-00 Pb . . 103.56 33.67 33.55 c1 . 71.00 23.15 23.25 __LI 307.56 100~00 100.60 This substance is insoluble in alcohol and also in hydroch1oric"acid Concentrated sulphuric acid freely liberates fumes of hydrochloric acid sulphate of lead being thrown down. Hydrosulphuric acid isolates chloride of diplatosammonium with evolution of hydrochloric acid and precipitation of sulphate of lead which however always carries down a portion of platinum and renders it necessary to estimate the lead in the above analysis as sulphate by adding sulphate of ammouia and free sulphuric acid.A convenient method of preparing this salt presented itself as a matter of course in the direct union of the two chlorides the com-bination being promoted by adding hydrochloric acid which facilitates also the regiilar crystallisation. CONTAINING DIPLATOSAMMONIUM. In the case of precipitation by acetate of lead as might have been foreseen the mother-liquor yielded on concentration crystals of acetate of diplatosamine to identlfy which the substance was con-verted into chloride by adding hydrochloric acid evaporated to dryness and after solution in water precipitated by alcohol.The platinum obtained by ignition left no doubt of the composition of this salt.* The deportment of chloride of diplatosammonium with chloTide of lead induced me to study several other double compounds of this substance. CHLORIDE OF DIPLATOSAMMONIUM AND PROTOCHLORIDE OF MERCURY. This substance falls as a bulky crystalline salt which is easily soluble in boiling water from which after filtration it recrystallises in plumose groups composed of a multitude of cubes. The solution when rapidly cooled yields nacreous plates not unlike those of the lead-salt. This substance like all those hereafter described produces more regular forms from an acid than from a neutral solution ; and its insolubility in hydrochloric acid may be seen by its addition causing a partial precipitation in the saturated aqueous solution.I 0,6574gms. of salt dried at 120° gave on ignition 0.2130 , , platinum. 11. 0.5022 , , salt gave 0.1640 , , platinum. 111. 05156 , , saltgave 0*4874 , , chloride of silver equal to 0*1205 , , chlorine. IV. 0.5196 , , salt gave 044880 , , chloride of silver 0.1207 , , chlorine. From these numbers the following per-centages are deduced 1. 11. 111. IV. I__ Platinum . . 32.49 32.65 -Chlorine -23.37 23.23 0.4050 gms. of substance gave 0.2838 , , platinum. The theoretical and experimental per centages are for Pt H N C1 Theory. Experiment. Platiniim . . 58.75 58.51 MR G. B BUCKTON ON DOUBLE CHLORIDES which are in accordance with the formula Pt H N C1.Hg Cl. The numbers required by theory and obtained by experiment are annexed for comparison. Theory. Ekperimental mean. r-L -7 Pt . 99.0 32.58 . 6.0 1*97 -__I K4 . 28.0 921 I-Tg . 100.0 32.89 -c12 . 71.0 23.35 23.30 3049 100*00 This compound bears a considerable temperature without deeom- position At a certain point it fuses emitting dense fumes of chloride of ammonium and chloride of mercury. The residue after ignition consists of a compact foil of pure platinum which lines the vessel in which the operation is made. CHLORIDE OF DIPLATOSAMMONPUM AND SESQUICHLORIDE OF IRON. The union of these solutions does not result in the formation of a double chloride ; but a yellowish granular substance is deposited nearly insoIuble*in water and in ammonia.This salt yields a yellow solution with caustic potash from which it is again thrown down by addition of hydrochloric acid. The potash solution liberates am-monia on boiling and the dry salt disengages hydrochloric acid when treated with sulphuric acid. I 0.3978 gms. of substance dried at 110"gave on ignition 0.1922 , ) platinum. 11. 0.3970 , , substancegave 0.1930 , , platinum corresponding to the per-centages 1. liI. Platinum . . 48.31 48-63 This salt is therefore the chloride of Gros' radical Pt c1 H N . Cl which requires the following theoretical numbers. Theory. Mean of Expenmenr Platinum 48.41 48.46 CONTAINING DIPLATOSAMMONIUM. After precipitation of the iron solution by an excess of the platinum- salt it will no longer strike a black colour with tincture of galls; and ferrocyanide of potassium also throws down a nearly colourless pre- cipitate thus proving that the iron has been reduced from the sesqui- chloride to the protochloride the disengaged equivalent of chlorine having united itself to the platinum-chloride thus Pt H6N c1 + Fe c1 = Pt c1H6 N, c1 +2 (Fe cr) The salts of protoxide of iron do not appear to be acted upon chloride of diplatosammonium.CHLORIDE OF DIPLATOSAMMONIUM AND CHLORIDE OF ZINC. On mixing the concentrated solutions a very soluble salt falls which may be recrystallised in colourless plates possessing the general characters of the substances previously described. It may be conveniently purified by precipitation from the aqueous solution by alcohol and after drying the mass reproducing the crystals from boiling water.This substance was dried at 1104 and gently heated with carbonate of soda. After washing the mass with water it was digested with sulphuric acid and the platinum-black produced was ignited and weighed. I. 0.6562gms. of substance gave 0.2734 , , platinum. 11. 0-51’76 , , substance 0.6282 ,j , chloride of silver or 011554 , , chlorine. The calculated per-centages are for I. TI. Platinum . . 41.66 -Chlorine . .-30.02 which agree with the formula Pt H Nz C1. Zn C1. The theoretical and experimental numbers for 100 parts are Theory. Experiment Pt -=--Y99.00 41.86 41*66 H6 Zn Nz . . . .6.00 28.00 32.52 2.54 11-84! 13.74 -I - el . 71*00 30.02 30.02 236.52 100*00 218 MR. G. B. BUCKTON ON DOUBLE CHLORIDES CHLORIDE OF DIPLATOSAMMONIUM AND CHLORIDE OF COPPER. This double compound is immediately formed on mixing the two concentrated solutions. After washing the precipitate from the copper-salt which should be in slight excess and drying it at looo it has a beautiful olive-green colour and is composed of yellow plates possessing a metallic lustre. As this salt is decomposed by boiling water it cannot be purified by recrystallisation which perhaps may be taken as some apology for the following numbers which are only approximative yet sufficiently near to establish the formula. A weighed portion was gently ignited with carbonate of soda until all ammonia was driven off; and after washing the mass it was dissolved in nitrohydrochloric acid concentrated and then treated with chloride of ammonium and a large excess of alcohol.The platinum was determined by igniting the ammonio-bichloride obtained and the copper was estimated from the filtrate by adding potash with the usual precautions. I. 0.7600 gms. of substance gave 0.3166 , , platinum and 0.1364 , , oxide of copper or 0.1088 , 9) copper. 11. 0.6458 , , substance gave 0.1126 , , oxide of copper or 0.0898 , ,> copper* 111. 0.6948 , , substance gave 0.2875 , , platinum. The per-centages are I. 11. 111. Platinum . 41.65 41.37 I Copper . . 14-31 13.90 -From which is deduced the formula Pt H N C1.Cu C1. The theoretical and experimental numbers are Theory. Experimental mean. r--h- Yt . * 99.00 41.2 41.51 cu HI3 N . . . 6.00 28-00 31.66 2.54 11.85 13.41 -14.10 c1 . . 73-60 30.30 - 236.26 100*00 CONTAINING DIPLATOSAMMONIUM. Previous to solution in water the crystals of this substance become colourless and on applying heat a heavy granular salt is formed which exibits all the reactions of Gros' chloride. The supernatant fluid which becomes of a pale green hue after sufficient concentra- tion is precipitated by alcohol in the form of greenish films which may be regarded as the corresponding salt of the subchloride of copper and diplatosammonium as an exactly similar substance results from the union of these bodies a hydrochloric solution of the former being employed.The reaction therefore appears to be similar to that observed in the case of sesquichloride of iron. The change may be thus expressed in the form of an equation :* 2(Pt H N C1 Cu Cl) =Pt H N C1. Cu C1+ Pt C1 H6 N C1. The double salt containing the chloride of copper is easily soluble in potash with which it forms an intense blue. It is decomposed by heat with deposition of oxide of copper. CHLORIDE OP DIPLATOSAMMONIUM AND PROTOCHLORIDE OF TIN. On adding an acid solution of the latter to the platinum-salt a white voluminous precipitate falls which is easily dissolved by heat ;and the solution again deposits delicate films on standing which possess the external character of the compounds previously described.The crystals however in this case are always more or less coloured by binoxide of tin. This decomposition is hastened by heating the solution which turm to a deep port-wine red colour and deposits a powder composed of reduced platinum and binoxide of tin chloride of ammonium being formed at the same time. CHLORIDE OF DIPLATOSAMMONIUM AND BICHLORIDE OF TIN may be obtained in a dry state by precipitation in a strong acid solution and subsequently washing the mass first with hydrochloric acid and then with alcohol. From the difficulty in obtaining these salts of tin in a sufficient' state of purity no attempt was made to obtain a quantita-tive analysis. Chloride of diplatosammonium and chloride of barium throw down from their saturated solutions a crystalline precipitate which proved to be merely the latter salt isolated by the difference of its affinity for water.* This equation probably does not express the whole reaction as a secondary product mag be obtained in small quantitj from the filtiate in ncicular groups. 220 MR. G. B BUCKTON ON DOUBLE CHLORIDES Nitrate of suboxide of mercury does not form any double compound when added to chloride of diplatosammonium ; and no union of chlo- ride of silver with the latter substance could be effected even when it was previously dissolved in ammonia. BICHROMATE OF DIPLATOSAMINE. Considering the well marked affinities of this base I was curious to study its behaviour under the influence of chromic acid thinking it not improbable that an interesting product of oxidation might arise from the action.Chromic acid forms with chloride of diplatosamrnonium an abun-dant yellow precipitate sparingly soluble in cold water and resembling chromate of lead. From a hot solution it is deposited in minute cubic grains which are insoluble in alcohol and appear to be unaffected by dilute sulphuric acid. They do not contain chlorine; but hydrochloric acid is found in the filtrate after precipitation of the yellow salt. For analysis advantage was taken of the peculiar action of alcohol and hydrochloric acid upon the solution of this substance which in boiling is resolved into sesquichloride of chromium aldehyde and a crystalline substance which proved to be the chloride of Gros' radical.* As the substance is slightly decomposed at looo,the salt was dried in vucuo,dissolved in water reduced by alcohol and hydrochloric acid evaporated nearly to dryness and seven or eight times the volume of alcohol added to render the platinum-salt insoluble.After standing this salt was filtered off and ignited and the sesquioxide of chro- mium subsequently precipitated from the filtrate by ammonia. In another instance the chromic acid was precipitated by acetate of lead and the platinum was obtained by igniting the salt in the filtrate. I. 0.6366 gms of substance gave 0.8443 , , chromate of lead equal to 0.1451 ,) , chromium and 0.2594 , , platinum. * 0,5290 gms. af this substance gave on ignition 0.2566 , , platinum.The chloride of Gros' salt (Pt C1 H N,. Cl) requires Theory. ExperimentI Platinnm . 48.41 48.50 221 CONTAINING DIPLATOSAMMONIUM. -..4.-11. 0.5448 gms. of substance gave 0.1776 , , sesquioxide of chromium or 0.1238 , , chromium aud 0.2224 , , platinum. 111. 0,7498 , , substance produced 0.2381 , , sesquioxide of chromium 0.1669 , , chromium and 0.3037 , , platinum. The per-centage composition I. IT. 1x1. Chromium . 22.79 22.72 22.26 Platinum . 40.74 40.08 40.51 This substance is therefore the bichromate of dipjatosamine the formula of which is Pt H6 N20.2Cr 0,. For comparison the numbers required by theory and the mean by experiment are subjoined Theory. Experimental mean. Pt . . 99.0 40.33 4044 .6.0 2.44 -H6 N . 28.0 11.41 -Cr . . 56.3 22.95 22.59 0 = . 56.0 22.85 __. 245.3 1oo*oo From these numbers it appears that the salt is anhydrous and SO far it has the anomalous constitution of the corresponding potash and ammonia compounds. The decomposition effected by alcohol and hydrochloric acid is represented by the following equation PtH,N20.2Cr0,+C,H,0.HO+5HC1= Pt C1 H N . C1+ Cr Cl + C H O,+ 7 HO. I have failed in obtaining more than two-thirds of the calculated nitrogen by igniting the substance with soda-lime; and no increase was observed by addition of a small quantity of sugar previous to burning. An explanation is found in the fact that pure nitrogen is energetically liberated when the salt is gently heated.The decom- position is accompanied with scintillation and the products are a black powder composed of platinum and sesquioxide of chromium MR. G. B. BUCKTON ON DIPLATOSAMMONIUM. nitrogen water and ammonia. The salt may also be kindled by live charcoal in a similar manner to gunpowder. The following equation represents this reaction 3(Pt H N 0.2Cr03)=Pt3+3 Cr 03+2NH,+12 HOf-4 N. An exactly similar decomposition was first observed by Hayes in the bichromate of ammonia; and the subject has since been more fully investigated by Messrs. Richmond and Abel. &lonochromate of diplatosamine is formed on crystallising the bichromate from an arnmoniacal solution when it is sometimes depo- sited in pale yellow groups of crystals having the lustre of floss-silk; at other times it forms large cubical masses.The analyses of this substance have not been very concordant ;but nevertheless the numbers are such as to leave little doubt of the formula being represented by Pt H N 0 .Cr 0,.The behaviour of this compound is similar to that of the bichromate and like that salt it is soluble in potash which does not liberate ammonia until it is boiled. From the foregoing remarks it will be seen that chloride of dipla-tosammoiiium does not in the generality of cases follow the order of double decomposition; but that a direct combination of the two chlo- rides in the above-mentioned instances ensues even when the preci- pitant does not happen itself to be a chloride. The platinum-radical has also a marked tendency to form these double compounds as it appears to be immaterial whether sulphate of diplatosamine be employed to precipitate chloride of copper or sulphate of copper be used with chloride of diplatosammonium.* The mercury-salts also seem to give the same result under like circumstances.The composition of these double chlorides is satisfactorily borne out by the observation of Peyrone that Magnus’ green compound is immediately formed on mixing chloride of diplatosammonium with a hydrochloric solution of protochloride of platinum. M agnus’ com- pound may be thus regarded as a binary salt of this series 2(Pt H,N .Cl)=Pt H N C1. Pt C1. Reiset also has described and analysed the red (yellow?) compound containing the bichloride of platinum the existence of which might have been foreseen after the existence of the above described bodies had been established.* In this case the precipitated salt is nearly colourless unless a little free hydro-chloric acid is present.

ISSN:1743-6893    

DOI:10.1039/QJ8530500213

出版商:RSC    

年代:1853

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MR. E. CLAPTON ON THE ACID OXALATES OF THE EARTHS. 223 XXI.-On the Acid Oxalates of the Earths. BY EDWARD CLAPTON. In the Annales de Chimie [Z] LXXIII 263 M. Berard describes a crystalline oxalate of baryta which he found to contain 45.04 per cent of baryta and accordingly viewed as consisting of the earth combined with twice the amount of oxalic acid contained in the neutral oxalate. M. Darracq had also previously observed a binoxalate of baryta.* A superoxalate of strontia of doubtful composition has since been described by Dr. Thompson. There have been however more recently some doubts cast upon the existence of superoxalates of this class of oxides; but the inves- tigations about to be detailed show that they can easily be procured in a distinct and definite form.ACID OXALATE OF BARYTA. When about equal quantities of saturated solutions of oxalic acid and chloride of barium are mixed together no cloudiness appears at first ;but after the lapse of perhaps a minute crystals begin to form and presently they fall in abundance. The crystals are very acute rhomboidal plates; they are soluble in 336 parts of cold water at 60' the solution reacting and tasting strongly acid; hot water decomposes them. When treated with a solution of ammonia an oxalate of ammonia is formed leaving behind oxalate of baryta. Potash acts similarly. The salt is not affected by alcohol or ether. After having been dried in vacuo the salt loses nothing at 212' F. but by a heat of 350' F. water is given off; it loses oxalic acid at about 400' F.Subsequently it is converted into carbonate with evolution of carbonic oxide. In order to determine the composition of this salt the following analyses were made I. 14.15 grs. of salt dried in vacuo were dissolved in dilute acid and the baryta was precipitated by sulphuric acid. 9.8 grs. of sulphate of baryta were obtained. 11. 12.6 grs. of a different preparation similarly treated gave 8.9grs. of sulphate of baryta. 111. 22.41 grs. heated to redness yielded 13.2 grs. oi car-bonate of baryta. * Ann. Ch. Phys. [2] XL 69. MR. EDWARD CLAPTON ON THE These results give the following per-centage amounts of baryta I. 11. 111. Average. Baryta . . 45.5 46.35 45.74 45.86 This accords well with the amount of baryta as calculated from the formula BaO .C 0,+ HO .C 0,-t HO Baryta . . 45.98 Oxalic acid . . 43.22 I) Water . 10.80 100*00 The mere heating of the salt at given temperatures so as to drive off its various constituents did not give very accurate numerical results ; the loss at 350' F. upon 22.41 grs. in an experiment of this character was 1-61instead of 1.21; at 400" P. it was 7-91.instead of 7.26. An organic combustion of the salt was made. 12.75 grs. yielded 6-38 grs. of carbonic acid and 1.6 grs. of water. The per-centage of carbonic acid is here 47.7 instead of 52.8 the loss being doubt- less caused by the retention of some carbonic acid by the baryta in the tube The amount of hydrogen in this as also in another experiment where 24.63 grs yielded 3.15 grs.of water little exceeds the calculated amount. 1st. Experiment. 2nd. Experiment. Calculated. 1.39 per cent. 1.42 per cent. 1*2per cent. ACID OXALATE OF STRONTIA. Upon mixing together strong solutions of oxalic acid and chloride of strontium crystals presently fall which are found to be of a mixed kind presenting large rhomboidal crystals and small octahedra. The general characters of the salt are similar to those of the acid baryta-salt. When heated to 212* many of the crystals became white in colour and water was given off having in some instances a slight acid reaction. The following estimations of the base were made I. 18.45 grs. dried at 212' yielded 12.8of carbonate of strontia. 11. 3345 grs. of a different preparation yielded 21.45 grs.of the carbonate. 111. 19 grs. of a portion which had crystallized slowlyfrom the solu- tion after the first crop of crystals had subsided yielded 11.3 grs. of the carbonate. ACID OXALATES OF THE EARTHS. 225 IV. 10 grs. dried in vacuo gave off 0.85 grs. of water at 212' F. and yielded 5.8 grs. of the carbonate. V. 5-55 grs. of the salt prepared by recrystallising the acid oxalate from solution in hot oxalic acid yielded 3.4 grs. of the carbonate. These results are very discordant giving respectively the following percentage amounts of strontia I. 11. 111. IV. V. Strontia. 48.7 45 41.79 44-55" 43.2 The amount of strontia is therefore in every instance less than would be given by the neutral oxalate viz.49 per cent but it exceeds that required by the formula SrO . C O,+HO .C O,+HO viz. 36.6 per cent. or SrO .C,O +HO .C,O, viz. 39.1 per cent. However in the third experiment the discrepancy is small. In all probability each sample of salt was a mixture of salts of different compositions ;but there can be no doubt whatever that they contained at least one acid oxalate of strontia. LIME-SALT. An attempt was made to produce an acid oxalate of lime by similar means but without success j the precipitate which fell had the appear- ance of neutral oxalate of lime and 6.15 grs. dried at 212' yielded 4 grs. of carbonate of lime; the amount obtained from a substance of the formula CaO .C 0 . I30 would be 4.2 grs. MAGNESIA-SALT.Very strong hot solutions of sulphate of magnesia and oxalic acid were mixed together. A white powder separated which was almost insoluble in water ;upon heating it water was quickly driven off; and by a red heat it was found that 8.97 grs. yielded 2 69 grs. of mag-nesia agreeing with the formula of the simple oxalate NgO .C 0,. HO which would have given 2.82 grs. Dr. Gladstone who has kindly watched over the progress of this investigation desires me to append the following remarks upon the theoretical bearing of these results "A principal point of interest connected with these acid salts is the corroborative evidence they afford of the bibasic character of the contained acid. ccOxalic acid may well be viewed as the first member of the series * Calculated as dried at 2120.VOL Va-NO. XIX. Q 226 ilz. CHARLES GERHABDT'S RESEARCHES ON THE C,l Hn-l O, or (viewing them as bibasic) C H,- 0,. This series advances by the addition of multiples of the increment C H, the superior members are succinic adipic pimelic suberic and sebacic acids. Pyrotartaric acid also has claims to be considered one of the same group. The properties common to these acids as well as oxalic acid are their general production by the violent oxidation of organic substances ;their resisting most methods of oxidation ;their being solid and crystalline at ordinary temperatures ;but capable of fusion and sublimation though partially decomposed if rapidly heated ;and their tendency to form acid as well as neutral salts and amidic acids as well as amides. Late investigations have tended to show that these acids should be considered bibasic; the arguments which have led to this conclusion a,pply equally to oxalic acid. The rational formula of the crystalline oxalate of baryta is therefore Ba 0 .HO .C 0,+-HO. "The series formed by the above-mentioned hydrated acids is as follows Oxalic acid c H 0 Succinic . * '8 H6 '8 Pyrotartaric Adipic . Pimelic . . c, H 0 ~,,HlOO,c1*H,2O* Suberic ... . ' c, H1408 ... Sebacic . . C, H, 0s)'

ISSN:1743-6893    

DOI:10.1039/QJ8530500223

出版商:RSC    

年代:1853

数据来源: RSC

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226 ilz. CHARLES GERHABDT’S RESEARCHES ON THE XXII.-Researches on the Anhydrous Organic Acids BY CHAS. GERHARDT. (Continuation from a Letter to Dr.WILLIAMS ON.) In continuing the researches of which I had the honour of COM-rnunicating the commencement to the Society I have found a valuable reagent not yet used in organic chemistry and extremely valuable for the preparation of various chlorides used in the formation of anhy- drous acids. This reagent is the oxychloride of phosphorus PO Cl, a liquid which effects the decomposition of a great number of salts as easily as it decomposes water and enabled me among other things to prepare Acetic chloride c w 0c1 ANHYDROUS ORGANIC ACIDS. a colourless liquid very mobile and boiling at 56' C.It fumes slightly in the air and is decomposed by water into acetic and hydro- chloric acids. With this new chloride I have obtained several new active compounds by double decomposition. I prepare acetic benzoate or benxoic acetate by the action of acetic chloride on dry benzoate of soda C H50,Na. The reaction is very brisk and is soon completed without the aid of external heat The syrup produced washed with water and carbonate of soda leaves an oil heavier than water neutral to test-paper and possessing an agreeable odour of Spanish wine. This oil is easily purified from water and other foreign matters by agitation with ether free from alcohol; and after the ether has been removed by a gentle heat the product shows by analysis the composition Boiling water renders it acid but the complete decomposition requires a long action; and the intervention of alkalies is needed as in the case of ethers.When subjected to distillation acetic benzoate separates at about 150' into anhydrous acetic acid (acetic acetate) and anhydrous benzoic acid (benzoic benzoate). There is evidently a double decomposition between two molecules This reaction perfectly explains the formation of anhydrous acetic acid as described in my last communication (from benzoic chloride and acetate of potassium). Acetic cuminate or cuminic acetate is obtained in the same manner as the above anhydride. Freshly prepared it is a fragrant oil which preserves its liquid form in a stoppered bottle; but a few moments contact with the air is sufficient to make it crystallise magnificent needles being formed until the mass assumes the appear- ance and consistency of frozen olive oil.Analysis shews that this change of state is accompanied by no change of composition of the body I have also succeeded in preparing in a state of purity benxoic cinnamate or cinnamic benzoate a heavy almost inodorous oil containing Q2 M. CHARLES GERHARDT'S RESEARCHES &c. 228 as well as the benxoic cuminate or cuminic benzoate a similar heavy oil containing Pinally also anhydrous cuminic acid or cuminic cuminate is obtained by the same process in the form of a heavy oil resembling a fatty oil an$ possessing a very faint smell. This oil also crys-tallises after a time; but the oil and the crystals present the same composition C, Hg2O3 -Cl Hll 0 1 am continuing these experiments with butyric valerianic and citrobenzoic acids and hope soon to be able to communicate my results to the Society.In concluding this notice I wish to call the attention of chemists to a remarkable analogy which exists between certain organic com-pounds belonging to the type water and certain others which I compare to the type hydrogen as represented by the following parallel which I submit to the consideration of experimenters. I. o Water :}Free hydrogen . . . 'Hl c H5 Hydride of Ethyl homo-c2H5 Alcohol. H} logous to marsh-gas . H } '2 '5}O Ether. '2 H5 c2H5}Ethyl . . . . . . c H '2 H H3 O )Aldehyde . . . 2 '10 Acetic acid. '2 H3 } Acetyl to be found . c2 o}0 Anhydrous C H3 0-acid acetic c2 H3 0 CH3 '2 H3 . ')Acetone . . . . '2C H3 H O} 0 Acetate of Methyl. This comparison enables me to foretel that acetyl and in general those oxygenised groups which act like hydrogen (oxygenisedradicals) will be obtained by the reaction of the corresponding chlorides on the metallic aldehydates; and in like manner the ketones by acting on the metallic aldehydates by the hydrochloric ethers. The experiments and considerations published on this last point by M. Chancel seem to me quite decisive.

ISSN:1743-6893    

DOI:10.1039/QJ8530500226

出版商:RSC    

年代:1853

数据来源: RSC

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NOTICES OF Papers contained in other Journals. Report upon “Original Gravities,” By Professors Graham Hofmann and Redwood. ADDRESSED TO THE CHAIRMAN OF THE BOARD OF INLAND REVENUE. SIR The subject of the present inquiry is the specific gravity of the worts of beer. When worts are fermented they lose in density and assume as beer a different specific gravity. This last is of course the only true specific gravity of the beer but the specific gravity of the worts is also named with reference to the beer as the original specific gravity of thebeer or the original gravity of the beer. A knowledge of the original gravity of beer is required to fix the drawback allowed upon beer when exported according to the terms of 10th Victoria cap. 5. By this Act a drawback is granted of five shillings per barrel of thirty-six gallons upon beer exported of which “ the worts used before fermentation were of not less specific gravity than 1.054 and not greater specific gravity than 1.081 and a drawback of seven shillings and sixpence per barrel upon beer of which the worts used before fermentation were not of less specific ‘I gravity than 1.081.” The original gravity of beer is directly observed by the brewer only who ascertains the specific gravity of the worts of each brewing opera- tion by means of the saccharometer or other form of the hydro- meter and preserves a record of the observation.To enable the revenue officer to arrive independently at the same information he possesses the beer only from which to infer the specific gravity of the worts.It is the special object of the following investigations to discover how the original gravity of beer may be ascertained most accurately from the properties of the beer itself. The question has already been examined by foreign chemists-by Otto and Zenneck and especially by Balling of Prague; as well as by Messrs. Dobson and Phillips of the department of Inland REPORT UPON OlEIGINAL GRAVITIES. Revenue whose previous researches have greatly facilitated the present inquiry. The same properties of the beer have been generally had recourse to as likely to throw light upon the original gravity of the liquid and obviously suggest themselves. These are-lo the specific gravity of the beer itself (the beer gravity); 2O the proportion of alcohol the beer contains (the spirit-indication of the beer) to be ascertained by distillation and other practical methods ; and 3O the proportion of unfermented solid matter held in solution by the beer (the extract or extractive matter of the beerj.The liquid from which the volatile alcohol has been expelled and which contains the extractive matter when made up again to the original volume of the beer by the addi- tion of the necessary quantity of water represents the beer without its spirit; and it is by the greater or less specific gravity of this liquid that the proportion of extract in the beer has been generally estimated. The extract gravity of the beer is thus obtained. As the alcohol of the beer is derived from the decomposition of saccharine matter only and represents approximately double its weight of starch-sugar a speculative original gravity might be obtained by simply increasing the extract gravity of the beer by that of the quan- tity of starch-sugar known to be decomposed in the fermentation.The inquiry would then reduce itself to the best means of ascertain- ing the two experimental data namely the extract gravity and the proportion of alcohol in the beer particularly of the latter. It would be required to decide whether the alcohol should be determined from the gravity of the spirits distilled from the beer; by the increased gravity of the beer when its alcohol is evaporated off; by the boiling point of the beer which is lower the larger the proportion of alcohol present ; or by the refracting power of the beer upon light-various methods recommended for the valuation of the spirits in beer.Original gravities so deduced however are found to be useless being in error and always under the truth to an extent which has not hitherto been at all accounted for. The theory of brewing upon a close examination of the process proves to be less siniple than is implied in the preceding assumption; and other changes appear to occur in worts simultaneously with the formation of alcohol which would require to be allowed for before original gravities could be rightly estimated. It was found necessary to study the gravity in solution of each by itself of the principal chemical substances which are found in fermented liquids.These individual gravities defined the possible range of variation in original gravity and they brought out clearly for the first time the nature of the agencies which chiefly affect the result. The use of cane-sugar is now permitted in breweries and the solution of sugar may be studied first as the wort of simplest compo- sition. The tables of the specific gravity of sugar solutions con- BEPORT UPON ORIGINAL GRAVITIES. 231 structed by Mr Bate have been verified and are considered entirely trustworthy. The numbers in the first and third columns of Table I. which follows are however from new observations. It is to be remarked that these numbers have all reference to weights and not to measures. A solution of cane-sugar which contains 25 grains of sugar in 1000 grains of the fluid has a specific gravity of 1010*1 referred to the gravity of pure water taken as 1000 ; a solution of 50 grains of cane sugar in 1000 grains of the fluid a specific gravity of 1020*2,and so on.The proportion of carbon contained in the sugar is expressed in the second column; the numbers being obtained from the calculation that 171 parts by weight of cane-sugar (C12Hll Oil) consist of 72 parts of carbon If parts of hydrogen and 88 parts of oxygen; or of 72 parts of carbon combined with 99 parts of the elements of water. It is useful to keep thus in view the proportion of carbon in sugar solutions as that element is not involved in several of the changes which precede or accompany the principal change which sugar undergoes during fermentation and which changes only affect the proportion of the oxygen and hydrogen or elements of water combined with the carbon.The proportion of oxygen and hydrogen in the altered sugar increases or diminishes during the changes referred to ; but the carbon remains constant and affords therefore a fixed term in the comparison of different solutions. TABLEI. SPECIFIC GRAVITY OF SOLUTIONS OF CANE-SUGAR IN WATER. Cane-Sugar in Carbon in 1000 Specific by parts by weight. Gravity. loo~$~ 25 10.53 1010*1 50 21.05 1020*2 75 32.58 1030*2 100 42.10 1040.6 125 52.63 1051 150 63.16 1061.8 175 73.68 1072.9 200 84.21 1083% 225 94.73 1095.2 250 105*26 1106*7 When yeast is added to the solution of cane-sugar in water or to any other saccharine solution and fermentation commenced the specific gravity is observed to fall owing to the escape of carbonic acid gas and the formation of alcohol which is specifically lighter than water; 171 grains of sugar together with 9 grains of water being converted into 92 grains of alcohol and 88 grains of' carbonic acid (C12HI OIT-+HO =2 C H 0,+4 (30,).But if the process of fer- 232 REPORT UPON ORIGINAL GRAVITIES.mentation be closely watched the fall of gravity in cane-sugar will be found to be preceded by a decided increase of gravity. Solutions were observed to rise from 1055 to 1058 or 3 degrees of gravity within an hour after the addition of the yeast the last being in the usual proportion for fermentation.When the yeast was mixed in minute quantity only such as of the weight of the sugar the gravity of the sugar solution rose gradually in four days from 1055 to 1057.91,or also nearly 3 degrees ;with no appearance at the same time of fermentation or of any other change in the solution. This remarkable increase of density is owing to an alteration which takes place in the constitution of the cane-sugar which combines with the elements of water and becomes starch-sugar a change which had been already proved by H. Rose and by Dubrunfaut to precede the vinous fermentation of cane-sugar. The same conversion of cane-sugar into starch-sugar with increase of specific gravity may be shown by means of acids as well as of yeast.A solution of 1000 parts of cane-sugar in water having the specific gravity 1054.64 became with 1 part of crystallised oxalic acid added to it 1054.7; and being afterwards heated for twenty-three hours to a temperature not exceeding 128' Fahr. it was found (when cooled) to have attained a gravity of 1057.63-an increase again of nearly 3 degrees of gravity. In the table of starch-sugar which follows the influence of this conversion upon specific gravity is shown by placing together the gravities of cane-sugar and of the starch-sugar into which it is convertible and which therefore contain equal quantities of carbon. TABLE11. COMPARISON OF THE SPECIFIC GRAVITIES OF SOLUTIONS OF CANE-SUGAR AND STARCH-SUGAR CONTAINING EQUAL QUANTITIES OF CARBON.Cane-Sugarcontained in 1000 parts by weightof Solution. Specific gravity of solution of Cane-Sugar. Specific gravity of solution of Starch-Sugar. 25 1010*1 1010*4 50 1020*2 1020*8 75 1030.2 1031.3 100 1040.6 1042-4 125 1051 1053.5 150 1061*8 1064.9 175 1072.9 1076 200 108393 1087.8 225 1095.2 1099.4 250 1106.7 11 11.4 REPORT UPON ORIGINAL GRAVITIES. When yeast is added to a solution of starch-sugar or of cane-sugar previously converted by means of oxalic acid or by yeast itself into starch-sugar the rise of gravity described is no longer observed to precede fermentation. Hence the irregularity does not appear in an infusion of malt which contains starch-sugar and the attenuation of malt worts commences with the first action of the yeast and advances without interruption till the fermentation is completed.It is already evident from these statements that the original gravity of a fermented liquid or beer must be different according as it was derivedfrom a wort of cane-sugar or of starch-sugar. A eoniparison was next made of the specific gravities of solutions of pale and of brown malt with the solutions of the two pure sugars. The carbon determined by actual combustion in organic analysis is the same in all the four solutions of which the gravities are given in the same line and is the proportion which exists in 25 50 75 &c. parts of cane-sugar as in Table I. TABLE111. SPECIFIC GRAVITY OF SOLUTIONS OF PALE MALT BROWN MAkLT,AND STARCH-SUGAR CONTAINING EQUAL QUANTITIES OF CARBON.Parts of Cane-Sugar Solution of Solution of Solution of correspondingin 1000 Pale Malt. Brown Malt. Starch-Sugar. parts by weight of 1010*0 1010*0 1010*4 I 25 '1020.3 1020.2 1820*8 50 1030.6 1030.6 1031.3 75 1041.2 10419.2 1042.4 100 1052.1 1052-0 1053.5 125 1063-0 1062.9 1064.9 150 1074*2 1074.0 1076.0 175 1085.5 1085.5 1087.8 200 1097.2 1097.2 1099.4 225 1109.0 1109.0 1111.4 250 It is interesting to observe how closely the gravities of the pale and brown malt agree together through the whole range of the Table. The gravities are often identical and in no case differ more than 0.2 degree. This indicates a greater uniformity of density in the worts of different varieties of malt than could have been anticipated and it gives a character of constancy to the density of malt wort which is highly satisfactory.The density of the malt worts also approaches that of the pure starch-sugar but is always a little less by about 1 degree of gravity REPORT UPON ORIGINAL GRBVITLES in 35. Malt wort appears indeed intermediate between the two pure sugars. We have for instance solutions containing an equal quantity of carbon which exhibit the following gravities Cane-Sugar . . 1072.9 Pale Malt . . 1074*2 Starch- Sugar . . 1076.0 Now if the whole carbon of malt wort were present in the form of starch-sugar the gravity of the wort should somewhat exceed that of the pure starch-sugar solution as a small proportion of alkaline and earthy salts exist in the malt infusion and must add to its gravity.The carbon present in the small quantity of albumen of the malt could not affect the result materially in either way. But there are two other substances related to sugar of which the interference in malt infusions may be anticipated namely Dextrin or the gum of starch and Caramel. These are both forms of the sugar principle the transition from the one condition to the other depending upon the fixation of the elements of water in the substance or the liberation of a proportion of water Observations were in consequence made of the gravities of pure solutions of dextrin pre- pared from starch and of caramel produced by the proper application of heat to sugar. TABLEIV. SPECIFIC GRAVITIES OF SOLUTIONS OF CARAMEL DEXTRIN AND STARCH-SUGAR CONTAINING EQUAL QUANTITIES OF CARBON.Solution of Caramel. Solution of Dex t rin . Solution of Starch-Sugar. Parts of Cane-Sugarorresponding in ZOO0 parts by weight of Solution. 1008.7 1009.7 1010-4 25 101 7.3 1019.3 1020*8 50 1026.2 1028*8 1031.3 75 1034.9 1038.3 1042.4 100 1043.8 1047.9 1053.5 125 1052.8 1057.3 1064.9 150 1062.3 1066.9 1076.0 175 1071.8 1067.6 10874? 200 1081*3 1086.3 1099.4 225 1091.0 1095.8 1111.4 250 It will be observed that the gravities of both caramel and dextrin are considerably less than those of starch-sugar and that consequently REPORT UPON ORIGINAL GRAVITIES. the presence of either of these substances taking the place of starch-sugar in a malt infusion must lower the specific gravity of the latter.The following solutions of the three different substances containing the same quantity of carbon appear by the Table to have different gravities Starch-Sugar Dextrin . . . . 1076 1066.9 Caramel . . 1062.3 The solution of cane-sugar containing the same quantity of carbon has the specific gravity of 1072.9 and contains 175 grains of cane-sugar in 1000 grains of the solction or 17.5 per cent of cane-sugar. It follows that this proportion of the saccharine principle may present itself with specific gravities varying from 1076 to 1062.3 in the different forms which it can assume. A certain quantity of dextrin generally exists in the wort of malt which may be thrown down by alcohol.Dextrin was prepared in a pure state from this source. Its presence is of course due to the incomplete saccharization of the starch of malt in the process of mashing With regard to the existence of the other substance caramel in malt infusions the extreme facility with which starch-sugar is altered by heat would lead us to look for the production of caramel in the kiln-drying of malt particularly of brown malt. Its production is indicated by the dark colour of the infusion of the highly dried malt. Of the 3 or 4 per cent of black malt used for colouring porter the whole soluble portion appears also to be caramel. It may be further added that the use of caramel prepared from sugar as a colouring ingredient of porter is now permitted in breweries.A substance resembling caramel in some of its properties is de- veloped in fermented liquids in another way. The saccharine matter of the wort is never wholly converted into carbonic acid and alcohol in the most favourable circumstances a portion of solid matter always remaining which is no further fermentable even after the alcohol is distilled off and fresh yeast applied. This residuary matter is generally spoken of as a gummy substance but when obtained by the fermentation of pure sugar it partakes more of the characters of caramel or of glucic acid particularly in the low gravity of its solution in water. Of pure cane-sugar fermented 44 3.72 and 3.7 per cent was converted into this substance in three fermentations in which one and a half three and six measures of yeast were employed to one hundred measures of solution containing one-seventh of its weight of sugar.The extractive substance resembling caramel was obtained in the form of a dark brown syrup by evaporating the liquid after fer- 236 REPORT UPON ORIGINAL GRAVITIES. mentation had entirely ceased. It reddened litmus-paper contained lactic acid and was distinctly sour and slightly bitter to thc taste. That this residuary substance contained no longer any starch-sugar appeared from the fact that on mixing its diluted solution with caustic potash and heating it the colour was not sensibly darkened. It was no longer fermentable by yeast and it did not become so (like dextrin) after being boiled with sulphuric acid. It resembled caramel in giving with sulphate of copper and caustic potash in excess a transparent blue solution from which suboxide of copper was thrown down on the application of heat.It is precipitated by baryta-water and gives with subacetate of lead a brown precipitate which how- ever is more voluminous and paler in colour than the precipitate from pure caramel. Neutral acetate of lead precipitates a portion only of this substance proving that it is not a single principle but a mixture of two or more substances. A solution of it compared with that of caramel obtained by heating cane-sugar to 410' Fahr. and both containing the same proportions of carbon gave very similar densities. TABLE TT. SPECIFIC GRAVITIES OF SOLUTIONS OF CARAMEL FROM CANE-SUGAR AND OF THE EXTRACTIVE SUBSTANCE FROM THE FERMENTATION OF SUGAR CONTAINING EQUAL QUANTITIES OF CARBON.Solution of Extractive Parts of Cane-Sugar correspond-Solution of caramel. Substance. iirg in 1000 parts by weight of Solution. 1008.7 1008.9 25 1017.3 101 7.8 50 1026.2 1026.5 75 1034.9 1035.6 100 1043.8 1044.7 125 1052.8 1053.9 150 1062.3 1063.0 175 1071.8 1072.7 200 1081.3 1082.3 225 This extractive substance appears to interfere more than dextrin in giving lightness or apparent attenuation to fermented worts without a corresponding production of alcohol. Its effect becomes the more sensible the more nearly the worts are exhausted by fermentation. It is produced in the fermentation of both kinds of sugar and also of malt.There appears to be a certain uniformity in the proportion of saccharine matter which undergoes this change in every brewing REPORT UPON ORIGINAL GRAVITIES. judging from the correspondence of different beers in their gravities at the same stage of fermentation which shall afterwards be exhibited. It causes a marked irregularity in the progression of the gravities when the fermentation is carried to an extreme as it is in distilleries; but in brewing beer the fermentation is always arrested at a point in its progress too early to allow the effect of the extractive substance upon the gravity to become very conspicuous. The indication by gravity of the extractive substance is so much lower than that of starch-sugar that the former substance only indicates about five-sixths of the saccharine principle which has given rise to it.Hence it is that original gravities cannot be calculated on the assumption that the solid matter in beer is sugar or a substance having the same gravity as sugar. In the maturation of beer by time an increase of attenuationis observed which is no doubt chiefly due to the slow continuation of the vinous fermentation with the disappearance of sugar and for-mation of alcohol; but there is some reason to believe that the attenuation is not entirely due to that cause. Part of the loss of gravity appears to be occasioned by the change in condition of the saccharine principle from that of starch-sugar to the condition of the extractive substance a change which involves a loss of specific gravity without a corresponding production of alcohol.Another constituent of malt wort which should not be omitted is the soluble azotized or albuminous principle derived from the grain. The nitrogen was determined in a strong wort of pale malt with hops of the specific gravity 1088 and containing about 21 per cent of solid matter. It amounted to 0.217 per cent. of the wort and may be considered as representing 3.43 per cent of albumen. In the same wort after being fully fermented the nitrogen was found to amount to 0.134 per cent equivalent to 2.11 per cent of albumen. The loss observed of nitrogen and albumen may be considered as principally due to the production and growth of yeast which is an insoluble matter at the cost of the soluble albu- minous matter.Solutions of egg-albumen in water containing 3.43 and 2.11 per cent respectively of that substance were found to have the specific gravities of 1004.2 and 1003.1. Hence a loss of density has occurred during fermentation of 1.1 degree on a wort of 1088 original gravity which can be referred to a change in the proportion of albuminous matter. It will be observed that the possible influence of this substance and of the greater OF less production of yeast during fermentation upon the gravity of beer are restricted within narrow limits. The mineral constituents of the same worts consisting of soluble salts of the earths and alkalies amounted before fermentation to 0.443 per cent and after fermentation to 0.463 per cent.The REPORT UPON ORIGINAL GRAVITIES. proportion of these substances may therefore be supposed to remain con st ant. The process required for the determination of the original gravity of beer must be easy of execution and occupy little time. it is not proposed in the examination of a sample to separate by chemical analysis the several constituents which have been enumerated. In fact we are practically limited to two experimental observations on the beer in addition to the determination of its specific gravity. One of these is the observation of the amount of solid or ex-tractive matter still remaining after fermentation which is always more considerable in beer than in the completely fermented wash of spirits. A known measure of the beer might be evaporated to dry- ness and the solid residue weighed but this would be a troublesome operation and could not indeed be executed with great accuracy.The same object may be attained with even a more serviceable expression for the result by measuring exactly a certain quantity of the beer such as four fluid ounces and boiling it down to somewhat less than half its bulk in an open vessel such as a glass flask so as to drive off the whole alcohol. The liquid when cool is made up to four fluid ounces or the original measure of the beer and the specific gravity of this liquid is observed. It has already been referred to as to the extract gravity of the beer and represents a portion of the original gravity. Of a beer of which the history was known the original gravity of the malt wort was 1121 or 121 degrees ;the specific gravity of the beer itself before evaporation 1043; and the extract gravity of the beer 1056.7 or 56.7 degrees.The second observation which can be made with sufficient facility upon the beer is the determination of the quantity of alcohol con- tained in it. This information may be obtained most directly by submitting a known measure of the beer to distillation continuing the ebullition till all the alcohol is brought over and taking care to condense the latter without loss. It is found in practice that four ounce- measures of the beer form a convenient quantity for the purpose. This quantity is accurately measured in a small glass flask holding 1750 grains of water when filled up to a mark in the neck.The mouth of the small retort containing the beer is adapted to one end of a glass tube-condenser the other end being bent and drawn out for the purpose of delivering the condensed liquid into the small flask previously used for measuring the beer. The spirituous distillate should then be made up with pure water to the original bulk of the beer and the specific gravity of the last liquid be observed by the weighing bottle or by a delicate hydrometer at the temperature of 60° Fahr. The lower the gravity the larger will be the proportion of alcohol the exact amount of which may be learned by reference to the proper tables of the gravity of spirits. The spirit-gravity of the REPORT UPON ORIGINAL GRAVITIES.beer already referred to proved to be 985.95 ;or it was 24.05 degrees of gravity less than 1000 or water. The ‘‘spirit-indication ” of the beer was therefore 14.05 degrees; and the extract gravity of the same beer 56.7 degrees. The spirit-indication and extract gravity of any beer being given do we possess data sufficient to enable us to determine with certainty the original gravity ? It has already been made evident that these data do not supply all the factors necessary for reaching the required number by calculation. The formation of the extractive matter which chiefly disturbs the original gravity increases with the progress of the fermentation ;that is with the proportion of alcohol in the fermenting liquor. But we cannot predicate from theory any relation which the formation of one of these substances should bear to the formation of the other and are unable therefore to say beforehand that because so much sugar has been converted into alcohol in the fermentation therefore so much sugar has also been converted into the extractive substance.That a uniform or nearly uniform relation however is preserved in the formation of the spirits and extractive substance in beer-brewing appears to be established by the observations which follow. Such an uniformity in the results of the vinous fermentation is an essential condition. for the success of any method whatever of determining original gravities at least within the range of circumstances which affect beer-brewing. Otherwise two fermented liquids of this class which agree in giving both the same spirit-indication and the same extractive gravity may have had different original gravities and the solution of our problem becomes impossible.The fermentation of liquids of known composition and original gravity containing pure cane-sugar pure starch-sugar and the soluble matter of malt the latter both with and without hops was now repeated and the wort examined in each fermentation at ten or twelve different stages of its progress or after short periods of a few hours. The two required observations of the spirit-indication and extract gravity were made on every occasion with certain additional observations which shall again be referred to. The details of these and the numerous other fermentations referred to were conducted under our directions by Mr.Adam Young and Mr. C. B. Forsey (officers of Inland Revenue) lately of the Birkbeck Laboratory to whom we have great pleasure in acknow-ledging our obligations for the valuable aid which a perfect acquaint- ance with the subject and remarkable skill in experimenting, combined with the most untiring zeal could supply. The results of a particular fermentation of cane-sugar may be stated. Fifteen and a half pounds of refined sugar were dissolved in 10 gallons of water making 10%gallons of solution of which the REPORT UPON ORIGINAL GRAVITIES. specific gravity was 1055.3 at 60’; and after adding three fluid pounds of fresh porter yeast the specific gravity was 1055.95.The original gravity may be taken as 1055.3 (55*3 degrees). FERMENTATION OF SUGAR-WORT OF ORIGINAL GRAVITY 1055.3. I. 11. 111. xv. V. Number of Observation. Period of Fermentation. Degrees of SpiritIndication. Degrees of Extract Gravity. D egree of Extract Gravity lost. 1 Days.0 Hours. 0 0 55.30 0. 2 0 6 1-59 52.12 3.18 3 0 12 2.57 47.82 7.48 4 0 19 3.60 43.62 11-68 5 0 23 4.33 40.13 15.17 6 1 5 5-32 35.50 19.80 7 1 12 6.26 31.39 23.9 1 8 1 19 7*12 27.63 27.67 9 2 11 8.59 20.26 35-04 10 3 11 9.87 13.40 41.90 11 5 12 10.97 7.60 47.70 12 6 12 11.27 4.15 51.15 Columns III. and v. respectively exhibit the spirit which has been produced and the solid matter which has disappeared; the first in the form of the gravity of the spirit expressed by the number of degrees it is lighter than water or under 1000 and the second by the fall in gravity of the solution of the solid matter remaining below the original gravity 1055.3.This last value will be spoken of as ‘‘degrees of gravity lost ;” it is always obtained by subtract- ing the extract gravity (column IV.) from the known original gravity. To discover whether the progress of fermentation has the regularity ascribed to it it was necessary to observe whether the same relation always holds between the columns of “degrees of spirit-indication’’ and <‘ degrees of gravity lost.” It was useful with this view to find what degrees lost corresponded to whole numbers of degrees of spirit-indication. This can be done safely from the pre- ceding Table by interpolation where the numbers observed follow each other so closely.The corresponding degrees of spirit-indication and of gravity lost as they appear in this experiment upon the fer- mentation of sugar are as follows REPORT UPON OItIGINAL GRAVITIES. FERMENTATION OF SUGAR-WORT OF ORIGINAL GRAVITY 1055.3. Degrees of Degrees of Extract Spirit-Indication. Gravity lost. 1 1.71 2 4.74 3 9-26 4 13.48 5 18-30 6 22.54 7 27-01 8 31-87 9 37.12 10 42.55 11 47.88 In two other fermentations of cane-sugar the degrees of gravity lost found to correspond to the degrees of spirit-indicatio11 never differed from the numbers of the preceding experiment or from one another more than 0.9 degree of gravity lost.This is a sufficiently close approximation. FERMENTATION OF SUGAR-WORT OF ORIGINAL GRAVITY 1054.7 A; AND OF SUGAR-WORT OF ORIGINAL GRAVITY 1028.8 B. Degrees of Spirit- Indication. Degrees of Extract Gravity lost. A. B. 1 2-01 1-94 2 5.15 4.84 3 9.22 9.90 4 13.95 14.10 5 18.09 18.31 6 23.16 22-61 7 27-05 27.5 1 8 32.26 9 37.40 10 42.16 11 47.56 The observations of the three experiments were combined in the followiiig Table which exhibits the mean results. Besides the degrees VOL V.-NO. XIS. R of gravity lost corrcaponding to whole degrees of spirit-il7dication the degrees of gravity lost corresponding to tenths of a degree of spirit-indication are added from calculatioii. TABLE VI.-C A NE-SWAR.DEGREES OF SPIRIT-INDICATION WITH CORRCSPOSDIXG DEGREGS OF GRAVITY LOST. Degreesof Spirit-Indication -0 *3 *4 -5 *6 *9 0 - *2 -3 .5 -7 *9 1.0 1.2 1.4 1.6 1 1.9 2.1 2.4 2.7 3.0 33 3.6 3.9 42 4.6 2 5.0 5.4 5.s 6*2 6.6 7.0 7-5 8.0 8.5 9.0 3 9.5 99 10.3 10-7 11.2 11.G 12.0 12 4 12.8 13.3 4 13.8 14.2 14’6 15.0 15-5 l?:9 16.3 16.7 17 2 11.7 5 18.3 18.7 19.1 19.5 19 9 25.3 20.8 21.2 ’ 21.1 22.2 G 22-7 23.1 23.5 23.9 24-1 2 i.7 25.2 25.6 26.1 26.6 7 27.1 27.6 28.1 28-6 29 1 29.6 30-0 30.5 31.0 31.5 8 32.0 32.5 33.0 33.5 3 4.0 34.5 35.0 35-5 3G.0 36.6 9 37-2 37.7 38-2 38.7 39 2 39 7 40.3 40.8 41.3 41.8 10 42.4 42.9 43.4 44.0 44.5 45.5 45.6 46.1. 46% 47-2 11 47.? It is seen from this Table that for 5 degrees of spirit-indication the corresponding degrees of gravity lost are 18.3 degrees.For 5.9 degrees of spirit-indication the corresponding degrees of gravity . lost are 22.2 degrees. This Table is capable of a valuable application for the sake of which it was constructed. By means of it the unknown original gravity of a fermented liquid or beer from cane-sugar may be dis- covered provided the spirit-indication and extract gravity of the beer are observed. Opposite to the spirit-indication of the beer in the Table we find the corresponding degrees of gravity lost which last added to the extract gravity of the beer gives its original gravity. Suppose the sugar-beer exhibited an extract gravity of 7.9 degrees (1007*9) and spirit-indication of 11 degrees. The latter marks according to the Table 47.7 deeees of gravity lost which added to the observed extract gravity 7.9 degrees gives 55.6 degrees of original gravity for the beer (1055.6).The table which follows was constructed in the same manner for starch-sugar from two fermentations of the pure substance and gives the means of calculating the original gravity of liquids fermented from starch-sugar when the spirit-indication and extract gravity of the beer are known from experimcnt. The extreme deviation betwccn the two series of observations was 0.8degree of gravity lost. REPORT UPON ORfGlNAL GRAVITIES. TA B L E VII.-ST ARC H-SuGA R . DEGREES OF SPIRIT-INDICATION WITH CORRESPONDING DEGREES OF GRAVITY LOST. Degrees of Spirit-1 *2 *3 *4 *7 .9 Indication 0 - -3 -6 -9 1.2 15 1-8 2.1 2.4 2.7 1 3.0 3.3 3.7 4.0 4.4 5.0 5.0 5.4 5.8 6.2 2 6.6 7.0 7'4 7.8 8.2 8*6 9.9 9.4 9.8 10.3 3 10.7 11.2 11.5 12-0 12.4 12-9 13.3 13.7 14.1 14.5 4 15.0 15.4 15.9 16-4 16.8 17.3 17.7 18.2 18.7 19.2 5 19.7 20-1 20.6 21.0 21-5 22.0 2 2.5 23.0 23.5 24.0 6 24.5 25.0 25.4 25.9 26-4 26-8 2 7.3 27.8 28.3 28.8 7 29.3 29 7 30 2 30.7 31.1 31.6 32.0 32.5 33.0 33.5 8 34.0 34.5 35.0 35.5 36.0 36.5 37.0 37.5 38.0 38.5 9 39.0 39.5 40.1 40-6 41.1 41 7 42.2 42.8 43.3 43.9 10 44.5 45.1 45.9 46.5 The niimbers will be observed to differ frorn those of the precediiig Table for cane-sugar and to be all greater the differences increasing pretty uniformly with the higher degrees of spirit-indication.The corresponding nunibers for 10 degrees of spirit-indication are 42 4 in canc-sugar and 44.5in starch-sugar or a difference of 2.1 degrees of gravity lost.By this difference the original gravity of the beer of starch-sugar is increased over that of cane-sugar as should be the case ; the specific gravity of starch-sugar being always higher than that of cane-sugar containing an equal weight of carbon and capable of yielding an equal quantity of spirits. (See Table 11.) The three Tables for malt worts of different kinds which follow will be found to agree we12 with each other and also to accord closely with the preceding Table for pure starch-sugar worts. TABLEVII1.-PALE MALTWITHOUT HOPS. DEGREES OF SPIRIT-INDICATION WITH CORRESPONDING DEGREES OF GRAVITY LOST. Degrees of Spirit-*O -1 *2 *3 -4 5 -9 Indication I__ I__-0-3 *6 *9 1.2 1.5 1.8 2.2 25 2.8 1 3.2 3.6 39 4.3 4.6 5 0 5.4 5.8 6.2 6.6 2 7.0 7.4 7.8 82 8.6 8.9 9.4 9.8 10.3 10.7 3 11.2 11.6 12.1 12.6 130 13-4 13.8 14.2 14-6 15.0 4 1515 15-9 16.4 16.9 17.3 17.7 18.1 18-6 19.1 19*5 5 20-0 20.5 20.9 21-3 21.8 22.2 22.7 23.1 23.6 24.1 6 24.6 25 0 25.5 25.9 26.3 26.8 2 7.3 27.8 28-3 28.8 7 29.3 29.7 30.2 30.7 31.2 31.7 32.2 32.7 33.2 33.1 8 34.2 34.7 35.2 35.7 36.3 36-9 37.5 38.1 38.6 k9.1 9 39.5 40.0 40.5 41.0 244 REPOK'C UZ'ON ORIGINAL GRAVITIES.The results given are the means of the observations of two fer-mentations of pale malt without hops which accorded throughout within 1 degree of gravity. TABLEIX.-PALE MALTWITH HOPS. DEGREES OF SPIRIT-INDICATION WITH CORRESPONDING DEGREES OF GRAVITY LOST.Degreesof Spirit-Indication. *O *1 I I *2 1 *3 I '4 *5 -6 0 - -2 -5 -7 1.0 1.3 1.6 1.9 2.2 2.5 1 2-8 3.1 3.4 3.7 4.0 4.4 4.8 5.2 5.5 5-9 2 6.3 6.7 7.1 7.5 8.0 8.4 8-8 9.2 94 10.0 3 10.5 10.9 11-3 11.8 12.2 12.7 13.1 13.6 14.0 14.5 4 15.0 15.4 15.8 16.3 16.7 17'1 17.6 18.0 18.5 19.0 5 19.5 19.9 20.4 20.9 21.3 21.7 22-2 22.7 23.1 23-5 6 23.9 24.4 24.8 25.3 25.7 26 2 26.6 27.0 27.4 27.9 7 28.4 28.9 29.4 29.9 30.4 30.8 31.2 31.7 32.2 32.7 8 33.2 The results are the means of the observations of two fermentations of pale malt with hops which corresponded throughout within 0.49 degree of gravity lost. TABLEX,-BROWN AND PALTMALT.-EQUALWEIGHTS. DEGREES OF SPIRIT-INDICATIOhT WITH CORRESPONDIN6 DEGlCEES OF GRAVITY LOST.I Degrees of Spirit-'0 -1 *2 .3 '4 *5 *6 *7 *8 *9 Indication. ~ -~_____ ---0-3 -6 -9 1.2 1.5 1.8 2.2 2.4 2.8 1 3.1 3.4 3.7 4.0 4.3 4.7 5.1 5.5 5.9 6.2 2 6.6 7.0 7.4 7-8 8.2 8.6 9.0 9.4 9.8 10.2 3 10.5 10.8 11.3 11.7 12.2 12 6 13.0 13 5 13.9 14.0 15.2 15.6 16.1 16.5 17.0 17.4 17.8 18.2 18 6 19.4 19.8 20.2 20.6 21.0 21.5 22.0 22.5 23-0 23.9 24.4 24.9 25.4 25.9 26.4 26.9 27.4 27.9 28.7 29.2 29.8 30.3 30.8 31.3 31.9 324 32 9 34.2 34.9 35.8 This table was derived from a single experiment. No observation could be made upon brown malt alone as it could not be fully fer- mented without a considerable admixture of pale malt. For comparison the numbers corresponding to the integral degrees of spirit-indication of the five different Tables are placed together in the following Table REPORT UPON ORIGINAL GRBVITIES.TABLEXI.--VARIOUS WORTS. DEGREES OF SPIRIT-INDICATION WITH CORRESPONDING DEGREES OF GRAVITY LOST. V. Degreesof Spirit-Indication. I. Cane-Sugar. 11. Starch-Sugar. 111. ?ale Malt. IV. Pale Malt iith Hops Brown and Pale Malt. VI. lean of ii i iv & v. 1 1 *9 3.0 3.2 2.8 3.1 3.0 2 5.0 6.6 7.0 6.3 6.6 6.6 3 9.5 10.7 11.2 10.5 10,5 10.1 4 13.8 15 0 15.5 15.0 14.8 15-1 5 18.3 19.7 20.0 19.5 19.0 19-5 6 22.7 24.5 24.6 23-9 23.5 24.1 7 27-1 29.3 29 3 28.4 28-2 28.8 8 9 10 11 32.0 37.2 42.4 47.7 34.0 39.0 44.5 34.2 39 5 - 33.2 -- 33 5 - 33.9 39.25 44.5 The first point which excites attention is the general ,,milarity of all the four columns which refer to liquids containing the same fer- mentable substance starch-sugar.In comparing together columns 11. and III. those of starch-sugar itself and pale malt without hops the greatest difference observed between any two corresponding num- bers is 0.5 or half a degree of gravity. The numbers of the two columns are the same at one point but at all other places the starch- sugar column is slightly exceeded by the pale malt column. It thus appears that the phenomena of the fermentation of pale malt are closely represented by a solution of pure starch-sugar. The other substances besides sugar of which small quantities are known to be present in malt appear therefore not to be subjected to any change during the fermentation of the wort which materially affects the gravity of the latter.The addition of hops to the malt has a slight effect in lowering the gravity numbers as wen in column IV. to the extent at one point of 1degree of gravity. Brown malt appears to act in the same direction as hops upon the progression of gravities (column v.) but with less effect although the quantity of the former was made as large in the experiment as was consistent with fer- mentation and much greater than is ever employed by the brewer. The general mean of these four liquids all containing starch-sugar appears in column VI. The highest degree of original gravity which the sugar-solutions and malt infusions of the preceding Tables possessed before fer- mentation was about 1057 but it was desirable to extend the obser-vations to worts of higher gravities.Pale malt worts with hops which representing beer are of most interest were fermented they had in two experiments the original gravity 1087*9 and in one experiment 1121 and were frequently examined at different stages as before till all fermentation ceased. The three experiments gave REPORT UPON ORIGINAL GRAVITIES. numbers which did not diverge anywhere during their common range more than 0-7 degree of gravity and at the same time were in har- mony with the earlier experiments on pale malt with hops (Table IX.) The mean of the new experiments gave for six degrees of spirit- indication 24.0degrees of gravity lost instead of 23.9 degrees as in Table IX.; and for 7 degrees of spirit-indication 28.7 degrees of gravity lost in the place of 28.4,as in Table IX.TABLEXII.-B/IAL'I'-WORT OF HIGH ORIGINAL GRAVITY WITH HOPS. DEGRXES OF SPIRIT-INDICATION WITH DEGREES OF GRAVITY LOST. I__ Degrees *1 -2 *3 -4 -6 -8 -9 of Spirit. *O Indication 0 1 2 3 4 __I 5 ---22.1 22.5 23.0 23 5 6 24.0 24.4 24 9 25.3 25.8 26.2 26.7 27.2 27.7 28.2 7 28.7 29-2 29.6 30.1 30.6 31.1 31-6 32.1 32.6 33.1 8 33.6 34.1 34 7 35-2 35-7 36.2 36.7 37.2 37.7 38 2 9 38.7 39.2 39.8 40.3 40.8 41.3 41.8 42 3 42.8 43.3 10 43.8 44.3 44.9 45.4 45.9 46.4 47.c) 47.5 48.0 48.5 11 49-0 49.6 50.1 50.6 5 1.2 51.7 52.2 52.7 53.3 53.8 12 54.3 54.9 55'4 55-9 56.4 56.9 57.4 57.9 58.4 58.9 13 59.4 60.0 60 5 61.1 61-6 62 2 62-7 63.3 63.8 643 14 64.8 65-4 65.9 66.5 67.1 61.6 68.2 68.7 69.3 69.9 15 70.5 This last Table combined with Table XI.exhibits the relation between the spirits obtained by distillation from beer and the degrees of gravity which the original wort loses in producing the spirits through a range of gravity in the wort which ascends from 1000 to 1121. It is given in a complete form as Table A at the end of the Report. By means of Table A the original gravity of a specimen of beer may therefore be calculated back and ascertained from the two data which have been specified namely (l),the degree of spirit-indication which the spirits contained in the beer exhibit when made up with water to the same measure as the original beer; and (2) the extract gravity of the beer or the specific gravity of the beer deprived of its spirit and madc up to its original volunie with water.A specimen of beer when exanlined gave the following data Spirit-indication . 9.9 Extract gravity . . 1044-7 By Table A 9.9 degrees of spirit-indication represent 43.7 degrees of gravity lost; which added to 1044.7 the extract gravity of the same beer make up 1088.4 degrees the original gravity of the beer. REPORT UPON ORIGINAL GRAVITIES. 24’7 The two experimental data required to furnish means of deter-mining the original gravity of beer by the process already described are obtained with great precision when proper care is taken. One of these data however namely the spirit-indication of the beer involves the distillation of the beer and the collection of the whole alcohol without loss a delicate process which it has been attempted to supersede by operations of less difficulty and nicety.One of these operations long practised by the German brewers has been examined and recommended by Balling and has also been investigated by Messrs. Dobson and Phillips under whose notice it appears to have been first brought as a method which Mr. Stevenson of Edinburgh had suggested and attempted to carry out. The object is still to obtain the spirit-indication of the beer. The specific gravity of the beer is first observed by means of the hydro- meter or weighing-bottle. The extract gravity of the beer is next observed as in the former method; but the beer for this purpose may be boiled in an open glass flask till the spirits are gone as the new process does not require the spirits to be collected.The spiritless liquid remaining is then made up to the original volume of the beer as before. By losing its spirits the beer of course always increases in gravity and the more so the richer in alcohol the beer has been. The difference between the two gravities is the new spirit-indication and is obtained by subtracting the beer gravity from the extract gravity which last is always the higher number. The data in a particular beer were ae follows :-Extract gravity Beer gravity . . . . 1044.7 1035.1 Spirit-indication . 9.6 degrees. Now the same beer gave by distillation or the former method a spirit-indication of 9.9 degrees.The new spirit-indication by evapo- ration is therefore less by 0.3 degree than the old indication by distillation. The means were obtained of comparing the two indica- tions given by the same fermented wort or beer in several hundred cases by adopting the practice of boiling the beer in a retort instead of an open flask or basin and collecting the alcohol at thesame time. The evaporation uniformly indicated a quantity of spirits in the beer nearly the same as was obtained by distillation but always sensibly less as in the preceding instance. These experiments being made upon fermented liquids of known original gravity the relation could always be observed between the new spirit-indication and the degrees of specific gravity lost by the beer.Tables of the degrees of spirit-indication with their corresponding degrees of gravity lost were thus constructed exactly in the same manner as the Tables pifiich precede ; and these new Tables may be applied in the same way to ascertain 248 REPORT UPON ORIGINAL GRAVITIES. the original gravity of any specimen of beer. Having found the degrees of spirit-indication of the beer by evaporation the corrc- sponding degrees of gravity lost are taken from the Table and adding these degrees to the extract gravity of the beer also observed the ori$nal gravity is found. Thus the spirit-indication (by the evapo- ration method) of the beer lately referred to was 9.6 degrees which mark 43 degrees of gravity lost in the new Tables.Adding these to 1044.7 the extract gravity of the same beer 1087*7is obtained as the original gravity of the beer. As the numbers of the second set of Tables belonging to theevapo-ration process are derived from the same fermentations of cane-sugar starch-sugar and malt in different conditions as supplied the first series of Tables they give the means of forming a strict comparison between the spirit-indications obtained by the two processes. The want of coincidence between the two sets of Tables requires explanation. The same degrees of gravity lost give less spirit or in other words the same spirits or degrees of spirit-indication always give more degrees of gravity lost in the Evaporation Tables princi- pally from this circumstance.When alcohol is added to pure water the density of the latter undergoes a certain diminution. By an addition of eight per cent by weight of alcohol the density of water is reduced from 1000 to 986.7 which is a loss of gravity of 13.3 degrees. But eight per cent of alcohol in the same volume as before of water containing ten per cent. of cane-sugar occasions a loss of gravity of only 12-92degrees (a fall from 1036.47 to 1023055). The degrees of spirit-indication obtained are therefore less from the same absolute quantity of spirit in the sugar solution than in pure water Now the sugar solution containing alcohol represents the beer and gives the loss of gravity which the beer sustains by evaporation. On the other hand the first mixture of pure water and alcohol represents the dilute spirits obtained from the same beer by distillation.The results here are Degrees of spirit-indication 13.30 by distillation. 1 ?7 93 12.92 by evaporation. Difference . . 0.38 It thus appears that alcohol reduces the gravity of a solution of sugar or we may suppose infusion of malt not quite so much by a small quantity as it reduces the gravity of water. It has hitherto been believed that alcohol has the same effect upon the density of saccharine solutions as upon water in which case the spirit-indica- tions obtained from beer by the evaporation and distillation methods should necessarily be the same. But it appears from the following series of experiments on the subject that a sensibly greater condensa- tion always occurs when spirits are mixed with saccharine solutions thaii with water.REPORT UPON ORIGINAL GRAVITIES. TABLEXIII.-SUGAR DISSOLVED IN SPIRITS COMPARED WITH SUGAR DISSOLVED IN EQUAL VOLUMES OF WATER. Sugar, Alcohol in added to Specific Specific Spirit-Indi-5 ptrit-Incti-cation in 100 parts of 100 parts of gravity of gravity of cation in Solution of Solvent. Solvent. Solution. Water. Sugar. Solvent. 5 1000 1018.83 2 5 996.35 10 15-1 9 3.65 3.64 4 5 992.80 1011.74 7.20 7.09 6 5 989 63 1008 52 10.37 10.31 8 5 986.76 1005.70 13.24 13.13 10 5 983.91 1002*91 16 09 15.92 12 5 981.23 1000.35 18.77 18.48 -----.___--c_ 0 lo 1000 1036-47 2 10 996.35 1032.90 3-65 3.5 7 4 10 992.80 1029.49 7-20 6.98 6 10 989 63 1026 31 10.37 10.16 8 10 986.76 1023.56 13-24 12.91 10 10 983.91 1020.77 16 09 15.70 12 10 981-23 1018.23 18 77 18.24 0 15 1000 1053 2 15 996-35 1049.54 3.65 3.46 4 15 992.80 1046.24 7.20 6.76 6 15 989.63 1043.20 10.37 9.80 8 15 986.76 1940.42 13-24 12.58 10 15 983.91 1037-63 16.09 15.37 12 15 981.23 1035.06 18.77 11-94 --_ ---0 20 1000 1068.62 2 20 996.35 1065.26 3.65 3.36 4 20 992 80 1061.99 7.20 6-63 6 20 989.63 1059.06 10.37 9.56 8 20 986.76 1056.31 13.24 12 31 10 20 983.91 1053.52 16.09 15-10 12 20 981.23 1050 82 18.77 17.80 This increased condensation although small in amount will be found quite sufficient to account for the difference amounting to about 1.3 degrees of gravity in the higher numbers which holds between the gravities lost corresponding to the same degrees of spirit- indication in the two series of Tables.To obtain the correct original gravity of beer it is therefore necessary to make use of the proper Table according as the spirit-indication of the beer has been obtained by the distillation or by the evaporation method. The degrees of gravitylost thus found are added to the extract gravity which is the same in both modes of examination. Slthough the evaporation process is the easiest in practice yet it does not appear to admit of the same degree of precision as the dis-tillation process. In two experiments made upon the same beer a difference of 0.4 or 0.6 degree of original gravity is not unusual with the evaporation instead of the eoiiicideiicc almost perfect which holds REPORT UPON ORIGINAL GRAVITIES.in the repetition of the distillation. It is believed that the imperfect result of the evaporation depends chiefly upon the difficulty of observ-ing with accuracy the specific gravity of a frothing liquid like beer which is one of the data. The carbonic acid in the beer can have little influence otherwise 011 the result for it seldom constitutes more than one five-hundredth part of the whole weight of the beer. The gravity of the dissolved c'arbonic acid appears to exceed a little only that of water so that although the former is driven off entirely in the boiling it is replaced afterwards by a liquid (water) of nearly equal density when the extract gravity is observed.The carbonic acid thereforeis reckoned as so much water in the beer. The Tables of the mean results obtained from the various worts by the evaporation process are now subjoined. TABLEXIV.-CANE-SUBAR. DEGREES OF SPIRIT-INDICATION WITH CORRESPONDING DEGREES OF GRAVITY LOST. - Degreesof Spirit-Indication. -0 -1 - *2 -3 -4 -*5 - *6 *7 -8 -9 - 0 *2 *4 -6 -8 1.0 1.2 1.4 1.7 2.0 1 2.3 2-6 3.0 3.3 2.i 4.0 4.4 4.7 5.0 5.4 2 5.8 6.1 65 6-9 1.3 7.7 8.1 8.5 8-9 9.4 3 9.9 10.4 10.8 11.3 11.7 12.2 12.6 13.1 13.6 14.0 4 14.4 14.8 15.3 15.7 16.2 16.6 17.0 17.4 17.8 18.2 5 18.7 19.1 19.6 20.0 20.4 20.9 21.4 21.9 22.4 22.9 6 23.4 23.8 24.3 24.8 25.2 25.7 26.1 26.6 27.1 27 6 7 28.1 28.5 29.0 29.5 29.9 30.4 30.8 31.3 31.8 32.3 8 32 8 33.3 33-8 34.3 34 8 35.3 35.8 36.3 36.8 37.3 9 37.8 38.3 38.8 39.3 39.8 40 3 40.8 4 1.3 41.8 42.3 10 42.8 43.3 43.9 44.4 45.0 45.6 46.1 46.7 47.3 47.9 11 48.5 TABLEXV.-STARCII-SUGAR.-Degrees *l *2 of Spirit-0 '4 -5 *7 -8 *9 Indication 0 -3 .6 -9 1.2 15 1.8 2.2 2.5 29 1 3.2 36 4.0 43 4.7 5.1 5.5 59 6-3 6.7 2 7.1 7.5 7.9 8.4 8-8 9.2 9.6 10.0 10.4 10.8 3 11-3 11.7 12.1 12.6 13.0 13.5 13.9 14.3 14.7 15.1 4 15.6 16.0 16.5 16 9 17'4 17.8 18-3 18.7 19.1 19.5 5 20.0 20.4 20 9 21.3 21.8 22.2 22.7 23-2 23.7 24.2 6 24.7 25-1 25.6 26.1 26.6 27.1 27% 28.1 28 6 29.1 7 29.7 30.0 30.5 31-0 31.5 32.0 32.5 33.0 33.5 34.0 8 34.4 34.9 35 5 36.0 36.5 37.1 37.6 38.1 38.6 39.1 9 39% 4 0.2 40.7 41.2 41.7 42.3 42.8 43.3 43.8 44.3 10 41 8 45.3 45.9 16.4 4 7.0 47'5 45.0 48.6 49.1 49.6 REPORT UPON ORIGINAL GRAVITIES.25 1 TABLEXVI.-MALT WORTWITHOTJT HOPS. Degrees of Spirit -0 -1 -2 -3 .4 -5 *6 *7 -8 -9 Indication -._--_.--__. ---. --0 -3 -7 1.1. 1.5 19 2.3 2.7 3.1 3.5 1 3.9 4.3 4.7 5.1 5.5 5.9 6.3 6.7 7-1 7'5 8.0 8.4 88 9.2 9.6 10.0 10.4 10.8 11.2 11-6 2 12-0 12.4 12-9 13.3 13-7 14.2 14-6 15.0 1.5.4 15.8 3 4 1G.3 16.7 17.1 17.5 18.0 18.4 18.8 19.2 19.6 20.0 5 20.5 21.0 21.4 21.9 22.3 22.8 23.2 23-7 24-1 24.5 6 25.0 25.4 25.9 26.4 26.9 27.3 27.8 28.3 28.8 29.3 7 29.8 30.3 30.8 31.3 31.8 32.3 32.8 33.3 33.8 34.2 8 34.8 35.4 36.0 36.6 37.2 37.8 38.4 39.0 39.6 40.2 9 40-8 TABLEXVII.-MALT WORTWITH HOPS. Degrees of Spirit-*2 -3 *4 '5 06 *9 Indication 0 -3 -6 *9 1-2 1.5 1.8 2.1 2.4 2.7 1 3.0 3.3 3.7 4.1 4.4 4 *8 5.1 5.5 5.9 6.3 2 6.7 7.2 7.6 8.0 8.4 8.8 9-2 9.6 10.0 10.4 3 10.8 11.2 11.7 12.1 12.6 13.0 13-4 13.8 14.2 14% 4 15.0 15.4 15.9 16.3 16.8 17.2 17.7 18.1 18.6 19.0 5 19.4 19.8 20-3 20 7 21.2 21.6 22.1 22.5 22.9 23.3 6 23.8 24.2 24-7 25'1 25.6 26'0 26.5 26.9 27.4 27.8 7 28.3 28.7 29.2 29.7 30'2 30'7 31.2 31.7 32.2 32.7 8 33.2 TABLEXVIII.-BROWN AND PALEMALTWORTS.Degrees -4 -5 ' *6 *7 -8 *9 Indication _--- _I_ 0 - -3 *7 1.0 I -4 1.8 2.2 2.6 3.0 3.4 1 3.8 4.2 4.6 5-0 5.4 5.8 6.2 6.6 7.1 7.5 2 7.9 8.3 8.8 9.2 9.6 10.0 10 4 10.8 11.2 11.6 3 12.0 12.4 12.9 13.3 13.7 14.1 14.5 15.0 15.4 15.8 4 16-2 16% 17.0 17.5 17.9 18.4 18.8 19.3 19 7 20.1 5 20.5 20.9 21.4 21.8 22.3 22.7 23.2 23.6 24-1 24.6 6 7 8 25.0 29.6 344 1 25.4 30.0 25.9 30.5 j 26.3 30.9 26.8 31.4 27.2 31.9 27.7 32.3 32.8 28.2 28.7 33.3 29.1 33.8 I\lea11 of Tables XV.XVI. XVIT XVIII. Degrees of Spirit-1 -2 *3 -4 -5 -6 -7 -8 *9 Idication --_ ---*3 -7 1.0 1.4 1.7 2.1 2.4 2-8 3.1 1 3.5 3.8 4.2 4-6 5-0 5.4 5.8 6.2 6.6 7.0 2 7'4 78 8.2 8.7 9-1 9.5 99 10.3 10.7 11.1 3 11*5 11.9 12.4 12 8 13.2 13 6 14.0 14.4 14.8 15.3 4 '1 5.8 16 2 16.6 17.0 17.4 17.9 18.4 18.8 19.3 19.8 5 20.1 20.5 21.0 21.4 2 1-9 22.3 22.8 23.2 23.7 24-1 6 24.6 25.0 25.5 26.0 26.4 26.9 27.3 2 7% 28.3 28.8 7 29.3 29.7 30.2 30.7 31.2 31.7 32.2 32.7 33.2 33.7 R 34.2 34.7 35.3 35.9 36.5 :<?a1 35.7 38.3 38.9 39.5 n 40.1 no It 8 252 EEPORT UPON ORIGINAL GRAT'ITIES.TABLEXX.-MEAN OF TABLESXV. XVI, XVII. and XVIII. 1 213 4 5 6 7 8 9 10 -I -?---,-----~____I__-No. xv. 3-2 7.1 11.3 15.6 20.0 24.7 29.6 34.4 39.6 44.8 xvi. 3.9 8.0 12.0 16.3 20 5 . 25 0 29.8 34.8 40.8 xvii. 3.0 6.7 10.8 15.0 19.4 23.8 28 3 33 2 xviii. 3.8 7.9 12.0 16.2 20.5 25.0 29% ~ P -------34.4 --I Mean 3-5 7.4 11.5 15.8 20.1 24.6 29 3 34.2 40.2 TABLEXXL-MALT WORTOF HIGH ORIGINAL GRAVITY WITH HOPS. Degrees *2 -3 *4 *5 *6 -8 -9 Indication I-l- I_ - 0 1 2 3 4 5 21.0 21.4 21.9 22-3 22.8 23.2 23.7 24.1 24.6 25.0 6 25.4 25.9 26.3 26'8 27.3 27.8 28.2 28.7 29.1 29.6 7 30.0 30.5 30.9 31'4 31 9 32.3 32.8 33.3 33.8 34.3 8 34.8 35-3 35.8 36'3 36.8 37.3 37.8 38-3 38.8 39.3 9 39.8 40.3 40.8 41.4 41.9 42.4 43.0 43.5 44-0 44.5 10 45.0 45.5 46.1 46.6 47.2 47.7 48.2 48.7 49.3 49 8 11 50-3 50.9 51.4 51.9 52-5 53.0 53.5 54.0 54.5 55.0 12 55.6 56.2 56.7 57.3 5 7.8 58.3 58.9 59-4 59 9 60.5 13 11 G1.0 66.5 61.6 67.0 62.1 67 6 62.7 68.1 (33.2 68.7 63.8 69.2 64.3 69 8 64.9 70.4 65.4 70.9 66.0 71.4 15 72.0 In the examination of fermented liquids the acetic acid present should not be overlooked as the influence of this constituent upon the original gravity of some kinds of beer particularly old and hard beer is often considerable.There is however a certain amount of acid present in all healthy fermentations and this in the experiments on which our tables have been founded was estimated at one part of absolute acetic acid (C H 0,) in one thousand parts of wort.Any excess of acid beyond this should be ascertained by neutralizing the beer by an alkaline test-solution. Sixty parts (one equivalent) of acetic acid represent forty-six parts of absolute alcohol ; a proportion by which the weight of alcohol which has disappeared in the forma- tion of acetic acid is calculated. This corresponding weight of alcohol has a certain spirit-indication which is to be added to the spirit- indication of the beer itself before the degrees of gravity lost are taken from the table. The calculated original gravity of old beers is often thus very sensibly increased. The Tables for calculating original gravities constructed by Messrs. D ob son and Phillip s were deduced by these gentlemen from obser- vations made upon several different sacc harine solutions of known original gravity submitted to fermentation and are the same in prin- ciple as the Tables given in this Beport.The old observations appear to haw been made with the greatest care and accuracy and the Table founclcd upon thcm I\ hich has beeu ascd by the Excisc for somc time REPORT Ul’ON ORIGINAL GBAVITIES. 253 is alniost identical with Table A in the Appendix which we now give as the result of the more numerous and varied experiments subse- quently instituted during the present inquiry. The process of Professor Balling of Prague for ascertaining original gravities forms a part of a general method of analyzing beer which the author has developed in his great work upon Brewing.* The method is remarkable for the number of valuable results which are deduced by calculation from simple observations of the physical properties of the beer chiefly made by means of the saccharometer.The chemical properties of the extractive matter are not investigated and the source of the anomalies in the densities of fermented liquids are therefore left in the dark. But a certain number of observations have been made on the relation and dependence of the densities of the worts alcohol and extractive matter of particular fermented liquids. These observations afford empirical data for reaching the original gravity by means of a process of calxlation which is highly remarkable for its ingenuity and success considering the limited knowledge of the actual chemical changes involved in fer- mentation.In several samples of beer to which the formula of Balling was applied by us it was found to give an oripinal gravity within a single degree of the truth. Every facility and assistance in pursuing the necessary inquiries respecting fermentation on a large scale were afforded to us by the trade and we have much pleasure in acknowledging our obligations both to the partners and principal officers of the houses of Messrs. Abbott andSon; Combe Delafield and Co.; Furze and Son; Reid and Co.; Thorne and Co.; Truman Hanbury and Bux- ton and Whitbread and Co. of London; and to Messrs. Allsopp and Sons and Bass and Co. of Burton. We thus obtained the means of verifying the correctness of the origiual gravities calculated from our tables by means of specimens of beer of which the original gravity of the worts had been noted with sufficient acciiracy and which had been preserved for a considerable length of time.A series of experiments which had been made by Mr. Crockford of the Long Acre Brewery expressly with a view of illustrating the subject of original gravities and which he placed without reserve at our dis- posal and also a long series of most careful observations made by Mr. Bottinger in Messrs. Allsopp’s brewery were particularly pertinent to the inquiry and afforded a satisfactory confirmation of the sufficiency of the methods. The methods of determining original gravities already described are essentially empirical. But the investigations respecting the nature of the process of fermentation into which they have led * Die Gahrungschemie wissenschnftlich begriindet und in ihrw Anwendung auf die kl‘einbereitung Bierbrauerei Brenntweinbrennerei und Hefenerzeugung praktisch dargesteZLt von Carl J.N. Balling. Prague 1845. Or a shorter treatise by the same author-Die Sacchcirontetrische Bier-und Branntweinmei.vchpro6e. Prague 1846. 254 BEPORT UPON ORIGINAL GRAVITIES. suggested the principle upon which the rational process should be founded and which deserves to be explained for the better illustration of the subject. This process is chiefly interesting in a scientific point of view as it is too operose and delicate in the form in which it can be at present offered to supersede the preceding methods which are recommended for practice.The fact has already been insisted upon that the alcohol obtained from beer represents a perfectly definite quantity of starch-sugar and nothing else; and so furnishes a portion of the original gravity which is clear and indisputablc. The difficulty is with that portion of the original gravity which is represented by the solid matter remaining in the beer. Here also the difficulty would vanish if that solid matter were either all starch-sugar (which it never is} or entirely composed of the extractive niatter already described as frequently occurs in old hard beer. The gravities of solutions of starch-sugar and of the extractive matter are different but are now both fully known.If the solid matter of the beer consisted entirely of the former substance then the original gravity of the beer would be that of the joint amount of the starch-sugar actually found in the beer and of that represeuted by the alcohol of the beer the whole quantity of sugar being dissolved in water and having the original volume of the beer. The only further information required might be obtained from a Table of the gravities of solutions of starch-sugar. The specific gravity thus found of the solution of starch-sugar in question represents the original gravity of the beer. On the second supposition that the solid matter of the beer was all extractive matter (without sugar) then the reference should be made to a table of the specific gravities of solutions of different proportions of that substance such as Table V.page 236 but more extended. In a parallel column the gravities of solutions of starch-sugar possessing the same quantity of carbon as the extractive and corresponding to it would be placed and in another column the quantities of starch-sugar in the former solutions of that substance. Such a Table would give at once therefore the quantity of starch-sugar corresponding to the extractive and adding the quantity of starch-sugar represented by the alcohol of the beer the entire quantity of starch-sugar becomes known and the original gravity is found from it as in the preceding case. The problem therefore may be solved in the two extreme con-ditions of the beer which have been supposed. The real difficulty is with the intermediate condition which is also the most frequent one where the solid matter of the beer is partly starch-sugar and partly extractive; for no accurate chemical means are known of separating these substances,and so determining the quantityof each in the mixture.But a remedy presented itself. The fermentation of the beer was completed by the addition of yeast and the constituents of the beer were thus reduced to alcohol and extractive only frorri which the original gravity as is seen can be calculated. REPORT UPON ORIGINAL GRAVITIES. For this purpose a small but known measure of the beer such as four fluid ounces was carefully deprived of spirits by distillation in a glass retort. To the fluid when cooled a charge of fresh yeast amounting to 150 grains was added and the mixture kept at 80' for a period of sixteen hours.Care was taken to connect the retort from the commencement with a tube condenser so that the alcoholic vapour which exhaled from the wash during fermentation should not be lost. When the fermentation had entirely ceased heat was applied to the retort to distil off the alcohol; which was collected in a cooled receiver. About three-fifths of the liquid were distilled over for this purpose; and the volume of the distillate was then made up with water to the original volume of the beer. The specific gravity of the last spirituous liquid was now taken by the weighing bottle. To obtain a correction for the small quantity of alcohol unavoidably introduced by the yeast a parallel experiment was made with that substance.The same weight of yeast was mixed with water and distilled in another similar retort. The volume of this second dis- tillate was also made up by water to the beer volume; its specific gravity observed and deducted from that of the preceding spirituous liquid. This alcohol was added to that obtained in the first distilla- tion of the beer and the weight of starch-sugar corresponding to the whole amount of alcohol was calculated. This was the first result. For the solid matter of the beer the spiritless liquid remaining in the retort was made up with water to the beer volume and the specific gravity observed. A correction was also required here for the yeast which is obtained by making up the water and yeast distilled in the second retort to the original volume of the beer and deducting the gravity of this fluid from the other.The quantity of starch-sugar corresponding to this corrected gravity of the extractive matter was now furnished by the Table this was the second result. The two quantities of starch-sugar thus obtained were added together. The specific gravity of the solution of the whole amount of starch-sugar as found in the Table represented the original gravity of the beer. This method must give an original gravity slightly higher than the truth owing to the circumstance that the dextrin albumen and salts which are found among the solid matters dissolved in beer are treated as having the low gravity of extractive matter and accordingly amplified by about one-sixth like that substance in allowing for them ultimately as starch-sugar.The error from this source how-ever is inconsiderable. It is to be further observed that the error from imperfect manipulation of which there is most risk in the process is leaving a little sugar in the extractive matter from incom- plete fermentation. This accident also increases the original gravity deduced. The process has given results which are remarkably uniform and is valuable in the scientific investigation of the subject although not of that ready and easy execution which is necessary for ordina;.y practice and which recommends the former method. That REPORT UPON ORIGINAL GRAVITIES. method in its two modifications has been sufficiently described in the preceding pages and it now only remains to append the Tables required for its application which embody the general result of the inquiry.TABLEA.-To be used in ascertaining Original Gravities by the DISTILLATION PROCESS. DEGREES OF SPIRIT-INDICATION WITH CORRESPONDING DEGREES OF GRAVITY LOST IN MALT WORTS. Degrees of Spirit. -0 *1 -2 -3 .4 -5 a6 -7 *8 -9 Indication -___.- - 0 *2 *6 -9 1.2 1.5 1.8 2.1 2.4 2.7 1 3.0 3.3 3.7 4.1 4.4 423 5-1 5.5 5.9 6.2 2 6.6 7.0 7.4 7.8 8.2 8.6 9.0 9 *4 9.8 10.2 3 10.7 11.1 11.5 12.0 12.4 12.9 13.3 13-8 14-2 14.7 4 15.1 15.5 16.0 16.4 16.8 17.3 17.7 18.2 18.6 19.1 5 19.5 19.9 20.4 20.9 21.3 21.8 22.2 22.7 23-1 23.6 6 24.1 24.6 25.0 25.5 26-0 26.4 26.9 27.4 27.8 28.3 7 28.8 29.2 29.7 30-2 30.7 31.2 31-7 32.2 32.7 33.2 8 33.7 34.3 34.8 35.4 35.9 36.5 37.0 37.5 38.0 38.6 9 39.1 39.7 40.2 40.7 41.2 41.7 42.2 42.7 43.2 43.7 10 44-2 44-7 45.1 45.6 46.0 46 5 47.0 4 7.5 48.0 48.5 11 49.0 49.6 50.1 50 6 51.2 51.7 52.2 52.7 53.3 53.8 12 54.3 54.9 55.4 55.9 56.4 56.9 57.4 57.9 58 4 58.9 13 59.4 60.0 60.5 61.1 61.6 62 *2 62 7 63.3 63.8 64.3 14 64.8 65.4 65.9 66.5 67.1 67.6 68.2 68.7 69.3 69 9 15 70.5 TABLEB.-To be used in ascertaining Original Gravities by the EVAPORATION PBOCESS.DEGREES OF SPIRIT-INDICATION WITH CORRESPONDING DEGREES OF GRAVITY LOST IN MALT WORTS. -Degrees of Spirit-*I *2 *3 *4 *5 -6 *7 *8 -9 Indication 0 -3 -7 1.0 1.4 1.7 2.1 2.4 2.8 3.1 1 3.5 3.8 4.2 4.6 5.0 5.4 5.8 6.2 6.6 7.0 2 7.4 7.8 8.2 8.7 9.1 9.5 9.9 10.3 10.7 11.1 3 11-5 21.9 12 4 12.8 13.2 13.6 14.0 14.4 14.8 15.3 4 15.8 16.2 16.6 17.0 17.4 17.9 18.4 18.8 19.3 19-8 5 20.3 20.7 21.2 21.6 22.1 22.5 2 3.0 23.4 23.9 24+3 6 24.8 25-2 25.6 26.1 26.6 27 0 27.5 28.0 28.5 29.0 7 29.5 30.0 30.4 30.9 31.3 31.8 32.3 32.8 33.3 33.8 8 34.3 34.9 35.5 36.0 36.6 37.1 37.7 38.3 38 8 39.4 9 40.0 40.5 41-0 41.5 42.0 42.5 43.0 43.5 44 0 44.4 10 44.9 45.4 46.0 46.5 47.1 47.6 48.2 48-7 49.3 49.8 11 50.3 50.9 51.4 51.9 52.5 53.0 5 3.5 54.0 54.5 55.0 12 55 6 56.2 56-7 57.3 57.8 58.3 58.9 59.4 59.9 60.5 13 61.0 61.6 62.1 62.7 63.2 63.8 64.3 64.9 65.4 66-0 14 66-5 67-0 67.6 68.1 68.7 69.2 69.8 70.4 70.9 71.4 15 72.0 The Tables to be used for liquids fermented from cane-sugar and for liquids fermented from starcb-sugar are given at pages 242-3 of the Report for the distillation process and at page 250 for the evapora- tion process.Dlt. ANDERSON ON OPIUM. Besearches on some of the Crystalline Constituents of Opium.* By Thomas Anderson M.D. F.R.S.E. (Abstiacted by the Author.} Opium has been already submitted to investigation by so many chemists that it may at first sight appear to be an almost exhausted subject; but when we inquire more minutely into its history the meagre and often conflicting statements of different observers suffi- ciently indicate the necessity of more extended and minute inquiries before our knowledge of it can be considered as either definite or satisfactory.No less than tent basic and indifferent substances have been extracted from it; and of these the constitution of four only namely morphine codeine papaverine and narcotine has been satisfactorily established Of the remaining six porphoroxine is still unanaliysed ; opianine is of recent discovery and its composition still doubtful ; while the formuh attributed to thebaine pseudomorphine narceine and meconine are founded on old analyses made soon after their discovery at a time when the methods of organic analysis were comparatively imperfect and certainly cannot be looked upon as very satisfactory. For the preparation of the bases which form the subject of the following paper I have made use of the black mother-liquor of the preparation of rnuriate of morphine by the process of Robertson and Gregory.This fluid which is perfectly black and of the consistence of tar is diluted with water and filtered for the separation of a small quantity of flocky substance which deposits. Ammonia is then added as long as a precipitate is obtained which is separated by filtration through cloth and subjected to strong pressure. The precipitate thus obtained is dark-coloured and granular but if left in the press for any length of time is apt to run into a resinous mass. It must therefore be rapidly removed broken up with a small quantity of water and again expressed ; and this is repeated several times. The precipitate contains narcotine along with a considerable quantity of resin and a small quantity of thebaine.The fluid contains nar- eeine and must be preserved for its preparation. A portion of the precipitate is boiled with rectified spirit and filtered hot ;on cooling,. impure and highly-coloured crystals of nar-cotine are deposited which are collected on a cloth washed with a small quantity of alcohol and expressed ; the mother-liquor of these crystals is employed for the solution of another quantity of the pre- cipitate and so on until the whole has been dissolved. The impure crystals of narcotine are then rubbed up with a small quantity of a strong solution of potash and after standing for some time washed * Trans. Royal Society Edinburgh XX [3] 347. .F Since this paper was written two new substances have been added to the consti- tnents of opium ; these are the methylonarcotine and propjlonarcotine of Wertheim.POL. v.-NO. XIX. S 258 DR. THOJIAS ANDERSON ON SOME OE THE with water and finally crystallised several times from boiling spirit. The alcoholic solution from which the first dark-coloured crystals of narcotine are deposited on being distilled in the water-bath leaves behind a dark amorphous mass containing iiiuch resin mixed with a little narcotine and the whole of the thebaine contained in the original precipitate. It is treated with hot dilute acetic acid which dissolves the bases and a small quantity of resin. To this solution subacetate of lead is added until it acquires a distinctly basic reaction when the whole of the narcotine and resin are deposited and the thebaine remains in solution.The fluid is filtered from the pre- cipitate the excess of lead thrown down by sulphuric acid the sulphate of lead separated by filtration and the thebaine precipitated by ammonia. The washed precipitate is then dissolved in boiling alcohol and treated with animal charcoal and on cooling the fluid becomes filled with shining plates which are purified by several crystallisations. The mother-liquor of the original ammonia-precipitate contains narceine which is obtained in the following manner. A solution of acetate of lead is added to the fluid and the dirty brownish preci- pitate formed separated by filtration. The excess of lead is separated by sulphuric acid and the fluid saturated with ammonia is set to evaporate at a moderate temperature.When it has reached a certain degree of concentration a film appears on the surface and on cooling a quantity of crystalline matter is deposited which becomes more abundant on being allowed to stand for some days. This substance is collected on a cloth and washed with water and is then sometimes quite colourless but has more frequently a somewhat brown colour. It is then boiled with a large quantity of water and filtercd hot ;and on cooling the fluid becomes filled with fine silky crystals of narceine which are separated from traces of sulphate of lime by solution in alcohol and after boiling with animal charcoal and resolution in water are pure. NARCEINE. Narceine has been already analysed both by Pelletier and Couerbe; and from their results the former has deduced the formula C, H, NOl6 the latter CJgN, NO,, which though agreeing tolerably well with their analytical results are unsupported by determination of the atomic weight which neither of them appear to have attempted owing to the impression they derived from their experiments that narceine is incapable of entering into combina- tion with acids.My own experiments give for it the formula which was substantiated by the analysis of its platinurn compound CRYSTALLINE CONSTITUENTS OF OPIUM. which was found to contain 14.56 per cent of platinum and gave for the atomic weight of the base 464.8 while the theoretical number is 463. Narceine crystallises in delicate silky needles which mat together into a bulky mass.These crystals are always extremely white; and narceine is remarkable for the facility with which it is obtained colour- less. In cold water it is sparingly and in hot water readily soluble and the solution on cooling becomes filled with a network of bnlky crystals. It is more soluble in alcohol and insoluble in ether. Ammonia and dilute solutions of potash and soda dissolve it in larger proportion than water ; but the addition of a large quantity of concen- Crated potash precipitates it even from a hot solution in the form of an oily mass which remains fluid for some time under the solution. When boiled with dilute nitric acid the fluid acquires a yellow colour and on satriration with potash the odour of a volatile base is evolved.Concentrated nitric acid acts violently in the cold and oxalic acid is found in the solution. Strong sulphuric acid dissolves it in the cold with an intense red colour which passes into green on the application of heat. Strong hydrochloric acid dissolves it entirely without producing the blue colour described by Pelletier as characteristic of narceine. I did obtain a blue colour on one occasion but it was when operating on an impure specimen and I have never succeeded in obtaining it agaiii ;I have been equally unsuccessful with a specimen obtained directly from the establishment of Robiquet Pelletier and Caventou. This specimen differed in some respects from that which I had myself prepared and a single analysis gave results corresponding with the formula C, H, N.Olo; but I have no means of confirming its correctness as the high price of the material deterred me from further experiments.Hydruchlorate of Narceine is obtained sometimes in large groups of radiated needles and sometimes in the form of short thick irregular prisms. They are soluble in both water and alcohol and possess a distinctly acid reaction. Dried at 212' F. they have the formula c, H, NO, * H c1. SuZphate of Narceine is deposited in tufts of silky needles not differing much in appearance from the base itself. It is rather sparingly soluble in cold water readily in hot. Nitrate of Narceine is deposited in radiated groups from its hot solution. It is rather sparingly soluble in the cold. Chloride of Platinum and Narcezne.-When a solution of chloride of platinum is added to hvdrochlorate of narceine the double corn- po;nd makes its appearanie sometimes as a crystalline powder some- times in small prismatic crystals.Their forniula is C, HggNO, * HC1. Pt a,. s2 2GO DIL. THOMAS ANDERSON ON SOME OF THE THEBAINE. Three different formultx! have been given for thebaine by Pelletier Couerbe and Kane. They are Pelletier . ' c,* H18 NO6 Couerbe . . C2 HI,,. NO Kane * c2 Hl NO The atomic weight has been determined by the two latter chemists by ascertaining the quantity of hydrochloric acid gas absorbed by the base; Couerbe found 100 parts to absorb 8.35 of acid while Kane found it to absorb at 212' F. 16.96 per cent and at ordinary tem- peratures 33.28.These results are very nearly in the proportion of 1 2 and 4 ; but no reliance can be placed upon them as I have found that thebaine is vcry readily decomposed by hydrochloric acid and none of them agree with the atomic weight deduced from my own experiments. My analysis gives for it the formula differing from that of codeine by two equivalents of carbon. Thebaine crystallises from its alcoholic or ethereal solution in brilliant square plates having a silvery lustre. It is insoluble in water but very soluble in alcohol or ether especially on boiling. It dissolves readily in acids and forms salts which are not obtained in crystals from aqueous solutions. It is insoluble in potash and ammonia. Strong sulphuric acid reacts upoii it and produces a deep-red colour even when it is free from nitric acid.Concentrated nitric acid acts violently in the cold with copious evolutions of red fumes and for- mation of a yellow solution which becomes dark-coloured on the addition of potash and evolves a volatile base. In hydrochloric acid it dissolves readily and the solution 011 evaporation becomes dark- coloured and leaves behind a resinous matter which does not dissolve completely in water. Sulphuric acid of spccific gravity 1.300 dissolves it in the cold; and on gently heating a resinous or semi-solid matter is thrown down which on boiling with water slowly dissolves and deposits on cooling a rather sparingly soluble salt in microscopic crystals which appears to be a product of decomposition but of which I must defer the examination until I have obtained an additional quantity of thebaine.Chlorine and bromine rapidly decompose thebaine with the formation of resinous compounds. Hydrochlorate of Thebaine.-In order to prepare this salt thebaine is mixed with a small quantity of strong spirit and an alcoholic solu- tion of hydrochloric acid added until the thebaine is dissolved an excess being avoided and on standing thc salt is deposited in fine rhomboidal crystals. They are very soluble in water and the solu- CRYSTALLINE CONSTITUENTS OF OPIUM. tion on evaporation yields only a resinous mass. In alcohol espe- cially if absolute they are rather sparingly soluble and in ether they are insoluble. Dried at 212" F. their formula is C, H, NO,.HC1+ 2HO. Platinochloride of Theliaine is thrown down as a yellow crystalline powder on the addition of chloride of platinum to the preceding com- ponnd. It is sparingly soluble in hot water and the solution on cooling deposits a salt which appears to be a product of decomposi- tion. The formula of the salt dried at 212' is C, H, NO,. HC1. Pt C1,+2HO. Sulphate of Thebaine is obtained by adding sulphuric acid to an ethereal solution of thebaine partly in crystals partly as a resinous mass becoming crystalline on standing. The hydrochlorate gives with corrosive sublimate a fine white crystalline precipitate of a double salt and the base itself gives a bulky precipitate ;but neither of these substances could be obtained of constant composition.Terchloride of gold gives an orange-yellow precipitate which fuses at 212' into a resinous mass. ACTION OF NITRIC ACID ON NARCOTINE. When concentrated nitric acid is added to narcotine a very violent action ensues ; even in the cold red fumes are copiously evolved and a thick resinous-looking red matter is left behind. With somewhat weaker acid and a gentle heat a similar action takes place and a red fluid is obtained which by evaporation yields an amorphous orange residue. In both cases the action was much too violent and the pro- duct obtained obviously the result of several complex actions. The action of nitric acid in a more dilute state was therefore tried and after several experiments the following was found to be the most advantageous method of treatment.Six hundred grains of narco-tine are mixed with 2+ ounces by measure of nitric acid of specific gravity 1.400 diluted with ten ounces of water and exposed in the water-bath to an uniform temperature of 120' Fahr. The nar- cotine fuses into a yellowish mass which by continuous agitation slowly dissolves without the evolution of red fumes. When the solu-tion is nearly eomplete a small quantity of a white deposit begins to make its appearance in the solution and gradually increases in qinantity until the fluid becomes filled with bulky crystalline flocks. The quantity of this substance produced appears to depend to a great extent upon the rapidity of the oxidation being sometimes extremely minnte and always bearing a very small proportion to the quantity of narcotine employed.When these flocks have ceased to increase in quantity they are separated from the fluid by filtration through asbestos washed with water in which they are insoluble and purified by solution in a considerable quantity of boiling alcohol. To this substance I give the name of Teropiammoi2. As thus DR. THOMAS ANDERSON ON SOME OF THE obtained it is in the form of very sniall colourless needles in- soluble in water; sparingly soluble in cold and more soluble in boiling alcohol. It is little soluble in ether. Concentrated sulphuric acid dissolves it in the cold aiid the solution which is yellow g' 1ves a fine crimson on being heated. Nitric acid decomposes it. Hydro-chloric acid and ammonia have no action on it.Boiled with potash ammonia is evolved and opianic acid is found in the solution. I at first considered it identical with Wohler's opiammon but the absence of xanthopenic acid in this reaction and various other differences convinced me that it was not the same and this was confirmed by analysis which gave for it the formula CS0 H, NQ,,. That it is actually different from Wohler's opiammon of which the formula is C, H, NO,, is very obvious but it bears an interesting relation to it. The latter substance is derived from two equivalents of opianic acid and one equivalent of ammonia by the removal of the elenients of four equivalents of water as thus represented 2 eq. opianic acid . ' c, H20 1 eq. ammonia H3 N 02 4 eq. water . 4 04 1 eq.opiammon . c40 Hl N 01 and the new compound is derived in a precisely similar manner from three equivalents of opianic acid 3 eq. opianic acid . ' '60 H30 '30 1 eq. ammonia . H3N 1 eq. teropiainmon . ' '60 '29' '26 Both these substances therefore are produced in a similar man- ner from different opianates of ammonia ;and it is in consideration of this constitution that I give to my compound the name of tempi-ammon while I should propose that of binopiarnmon for Wohlefs substance and leave the name of opiav2mon for the compound simi- larly obtained from a single equivalent of opianic acid should it ever be discovered. The production of teropiammon in a highly acid fluid is a very remarkable phenomenon and one so far as I know of which we have no other example.It is obviously the result of a secondary action but it has appeared to me that it was most abundantly pro- duced when the action of the nitric acid was most moderate and I have never succeeded in obtaining it in larger quantity by continuing the action further. CRYSTALLINE CONSTITUENTS OF OPIUM. The fluid from which teropiammon has been separated is yellow and on supersaturation with potash deposits a crystalline powder. This was found to be cotarnine which can be obtained in this way much more readily than by Wohler's process. In the alkaline fluid from which the cotarnine had been separated it was natural to look for opianic acid and its presence was soon established as well as that of hemipinic acid and another substance which I call Opianyl.These substances were not however invariably all present opianic acid and opianyl being sometimes entirely absent and the latter being only found vhen the conditions of the oxidation were very successfully fulfilled. To obtain these substances the alka- line fluid is evaporated to a small bulk and the crystals of nitre which form are separated. The syrupy mother-liquor is treated with alcohol to separate carbonate of potash the alcohol distilled off and hydro- chloric acid added to the cold residue when there is obtained a preci- pitate containing opianic and hemipinic acids and opianyl. OPIANYL. This substance is only formed when the oxidation has been ex-tremely gentle and though repeated trials have been made it has been found impossible to moderate the action in such a way as to produce it at will.In order to obtain it in a pure state the preci- pitate by hydrochloric acid which has just been referred to is dissolved in a large quantity of boiling water and the solution allowed to cool. A crop of crystals is deposited which consists of opianyl along with some opianic acid if the quantity of water employed has not been sufficiently large. These crystals are purified by solution in boiling water and in alcohol. In one instance opianyl was obtained along with hemipinic acid and with only traces of opianic acid; and in that case its purification was conveniently effected by dissolving in boiling water precipitating hemipinate of lead with a solution of nectral acetate of lead washing the precipitate in boiling water and evapo- rating to a small bulk when opianyl deposited in colourless crystals which were purified by solution in boiling water.Opianyl is thus obtained in long colourless needles which are sparingly soluble in cold more so in hot water. When boiled with a quantity of water insufficient to dissolve it it melts under the fluid but when dry it requires a temperature of 230" Fahr. to produce its fusion and resolidifies at 220'. It dissolves both in alcohol and ether. Sulphuric acid dissolves it in the cold and the colourless solution acquires a fine and characteristic purple colour on heating. Boiling nitric acid decomposes it. It is not more soluble in potash soda and ammonia than in water and forms no compounds with the metallic oxides.Its analysis gave results corresponding to the formula 264 DR THOMAS ANDERSON ON SONE OF THE Opianyl thus bears an interesting relation to opianic and hemi- pinic acids provided we assume for the former the formula as cor- rected by Berzelius and for the latter an atomic weight twice as high as that assigned to it by Wohler both of which are consistent with my analyses. The three substances then stand as follows Opianyl . '20 8 Opianic acid . ' c20 HI0 010 Hemipinic acid . * c,o 4 012 and appear as three successive degrees of oxidation of the same radical. The derivation of opianyl from narcotine is abundantly simple Two equivalents of hydrogen are oxidised by the nitric acid and the narcotine splits up into opianyl and cotarnine as thus expressed Narcotine.Cot&nine. The same scheme with the addition of two or four equivalents of oxygen represents also the mode in which opianic and hemipinic acids respectively are derived from narcotine much more simply than it has been by Blyth in his paper on the action of bichloride of platinum on narcotine who gives a scheme involving the evolution of carbonic acid. The appearance of this gas which was actually observed by Blyth during the action has however always appeared to me to be the result of a secondary decomposition; and this view I think receives confirniation from the production of teropiammon where nitric acid acts even in the most feeble manner on narcotine and the formation of which must of necessity be attended by the evolution of carbonic acid.If we pursue the relations of opianyl to narcotine we shall find that these also are of a very interesting nature. By subtracting an equivalent of cotsrnine from one of narcotine Narcotine . ' '46 H% Cotarnine * ''26 6 we find that the substance coupled with cotarnine to form narcotine may be considered as a hydruret of opianyl or a substance bearing to opianyl a relation similar to that which alloxantin bears to alloxan and the preparation of which in a separate form would be most interesting. The attempts which I have made to obtain it have how- ever as yet proved abortive. 1 have tried the action of sulphuretted hydrogen upon opianyl but no change took place and also the fer- CRYSTALLINE CONSTITUENTS OF OPIUM.mentation of narcotine but with equally little success. It is possible that Wohler's sulphopianic acid C H, O,+S, may have some relations with this substance and in this point of view deserves a more extended examination. Rpdrate of OpianyL-On one occasion I obtained by acting on narcotine a substance similar in most of its properties to opianyl but which fused at 205OF. Its analysis corresponded to a hydrate of that substance C, H, 0 +HO but I did not again obtain it and I had not enough for a detailed examination Opianic Acid is obtained by evaporating the fluid which has de- posited opianyl. I have repeated its analysis for the purpose of fixing its formula and the results agree with C H, 01, the quantity of hydrogen being much too high for Wohler's formula C, H O,, although every care was talten in drying the material employed.Opianic Ether.-According to Woh1 er opianic ether cannot be obtained by the action of sulphuric or hydrochloric acid upon a miu- ture of opianic acid and alcohol; but I obtained it by chance with the latter acid and have confirmed its composition and found it to possess the properties attributed to it by the discoverer. Hernipinic Acid.-The analytical results obtained by W6 hler for this acid I have fully confirmed but I have found it to be a bibasic acid and its rational formula to be Cz0H, 012, or double of that given by him. This result is deduced from the analysis of an acid hemipinate of potass and from the formation of a hemipinovinic acid.Acid Hemipinate of Potash is obtained in the form of thick six- sided tables sometimes of considerable size which are readily soluble in water and alcohol but not in ether. It is highly acid to test- paper. The crystallised salt is represented by the formula KO .HO .C, 33 Ole+ 5HO. Neutral Henzipinate of Potash is highly soluble and crystallises with difficulty. Hernipinovinic Acid is prepared by passing a current of hydro- chloric acid through a solution of hemipinic acid in absolute alcohol. It is obtained in thue form of tufts of bdky needles sparingly soluble in cold more so in hot water. It fuses at 270' Fahr. but melts under water into a transparent fluid.It is strongly acid to test-paper. Its aqueous solution does not precipitate the salts of lead and silver but gives with perchloride of iron a bulky pale brownish-yellow preci- pitate. It dissolves readily in potash and the solution on boiling evolves alcohol. The crystallised acid has the formula C H 0 . 130. C, H 0, + IIO. Although it possesses distinctly acid properties and is capable of uniting with bases I have failed in obtaining its coriipounds in a state of purity. Its baryta-salt was obtained in tufts DR. THOMAS ANDERSON ON SOME OF THE of minute needles by digesting a solution of the acid with carbonate of baryta. But the compound was not obtained in a state fitted for analysis and appears to be very liable to undergo decomposition.ACTION OF NITRIC ACID ON COTARNINE. The products of the action of nitric acid on cotarnine are extremely complex and several different actions appear to occur simultaneously in each of which a different decomposition is produced. When the concentrated acid is employed oxalic acid is produced ;but when it is more dilute another acid is obtained which remains in solution in the nitric acid. The preparation of this substance is a matter of considerable nicety and it is particularly important that the nitric acid be not employed in too large an excess partly on account of the risk of carrying the action too far and partly on account of the difficulty of separating the product from a very large excess of acid. As the new product is liable to undergo a further oxidation with production of oxalic acid it is not safe to attempt its separation by evaporating the nitric acid solution.The best method is to dissolve the cotarnine in nitric acid diluted with about twice its bulk of water and then adding strong nitric acid to raise the mixture to the boiling-point. Red fumes are copiously evolved and after some time a little of the fluid is taken out and mixed with a considerable quantity of alcohol and ether. If on standing for a short time crystals are deposited the whole fluid is treated in the same manner; but if they do not appear the digestion is continued somewhat longer and it is tried again and so on until the right point is attained. The fluid mixed with alcohol and ether is allowed to stand for twenty-four hours and the precipitated crystals are separated by filtration.This sirbstance agrees in all respects with the apophyllic acid obtained by Wiiihler as a product of the action of bichloride of platinum upon cotarnine but which he obtained in too small a quantity for examination and analysis. ApophyEZic Acid.-The acid after being purified by cry stallisation and if necessary by animal charcoal presents all the characters attributed to it by Wohler and may be obtained either in hydrated or anhydrous crystals. It is soluble in water but not in alcohol or ether. It dissolves also in concentrated sulphurie acid. It fuses at 401' F. and on cooling solidifies into a crystalline mass. All its salts are extremely soluble. Its analysis gave results corresponding with the formula c, H N 08 which has been confirmed by the analysis of its silver-salt.Its for-mation froin cotarnine cannot be distinctly traced as several other substances arc formed simultaneously which I have not examined ; CRYSTALLINE CONSTITUENTS OF OPIUM. 267 but if we add to cotarnine two equivalents of oxygen and subtract from it the formula of apophyllic acid the difference is c, H Cotarnine + 20 c26HE3 '8 Apophyllic acid . ',,I3[ 7 '8 I have been unableto ascertain whether this group of atoms passes into any particular form of combination or whether it is entirely oxidised which is possible In its composition apophyllic acid is curiously related to anthranilic acid from which it differs by two equivalents of carbonic acid.c16 H N O*=C14 H N O,+2CO2 v-' u Apophyllic acid. Anthranilic acid. According to Wohler apophyllic acid when distilled yields a quantity of Chinoline; but now that its constitution is known we should rather expect the production of aniline which would be formed from it by the removal of four equivalents of carbonic acid thus c16 H7NO8-$ C02~C,2 H N By distillation I obtained a quantity of a base which had a slightly aromatic odour but gave no reaction of aniline with chloride of lime. I didnot obtain it in suEcient quantity for analysis. It is not the only product of decomposition a non-basic oil making its appear- ance at the same time. Apophyllate of Silver.-This salt can only be obtained by digesting the acid with moist carbonate of silver and precipitating with a mixture of alcohol and ether.It is thrown down as a crystalline powder which is very soluble in water and insoluble in alcohol and ether. It does not explode when heated but burns slowly and leaves metallic silver. It is represented by the formula Ago . c16 H NO,. Apophyllate and Nitrate of Silver.-When a solution of nitrate of silver is added to an alkaline apophyllate a sparingly soluble crystal- line salt is obtained which explodes violently when heated and has been described by Wohler as apophyllate of silver. It is however a compound of that salt with the nitrate of silver and is represented by the formula Ago . cl6H6 NO,+AgO . NO,. Apophyllate of Ammonia forms very small prismatic needles highly soluble in water.Apophyllate of Baryta is obtained by digesting the acid with carbonate of baryta and adding alcohol to the fluid when it is pre- cipitated in wart-like crystals. Associated with apophyllic acid another substance was once 268 ON SOME OF THE CRYSTALLINE CONSTITUENTS OF OPIUM. obtained in yellow needles the analysis of which gave results cor-responding with the formula C, HI NO,, but want of material has prevented its further examination and on another occasion a third substauce was detected. Both these substances deserve further examination. When the solution from which the apophyllic acid has been thrown down is distilled a syrupy fluid is obtained which on the addition of potash evolves the odour of a volatile base.In order to obtain this base a considerable excess of potash was added to the syrupy fluid and the whole distilled. A highly alkaline fluid passed into the receiver which was saturated with hydrochloric acid evaporated and the residue dissolved in absolute alcohol. The alcohol on distillation yielded a salt in fine scales which gave a fine golden-yellow double salt with bichloride of platinum and proved on analysis to be the platinum compound of methylamine. On another occasion the presence of ethylamine was detected ; and indications of another base with a much higher atomic weight were also obtained. The following is a tabular statement of the substances described in the paper. Narceine . * Hydrochlorate of narceine Platinochloride of narceine Robiquet' s narceine Thebaine €1y drochlorate of thebaine Platinochloride of thebaine HO Teropiammon .Opianyl . Hydrate of opianyl Opianic acid . Opianic ether . Hernipinic acid . Acid hemipinate of potash Heniipinate of silver . Hernipinovinic acid . Apophyllic acid Apophyllate of silver . Methylamine . Ethylamine . ON OXYGEN GAS FROM ATMOSPHERIC AIR. On the extraction of Oxygen Gas from Atmospheric Air.* Ry M. Boussingault. It is somewhat remarkable that no attempt has ever been made to obtain oxygen from the atmosphere in quantity sufficient for any useful purpose. In fact the celebrated experiment of Lavoisier in which he converted mercury into the red oxide by boiling it for a long time in the air and afterwards decomposing the resulting oxide at a red heat appears to be the only instance in which the oxygen of the air has actually been separated from the nitrogen and exhibited in the free state; and it is scarcely necessary to observe that the quantity yielded by this process is insufficient for any purpose beyond the mere demonstration of the fact.Among the very few substances which might be made available for the actual separation of oxygen from the air baryta appears to present the greatest advantages from its well known property of absorbing oxygen readily from the air at a low red heat and passing to the state of peroxide of barium which on subsequent exposure to a full cherry- red heat gives up its second atom of oxygen and is reconverted into baryta.The baryta may thus be reoxidised at a low red heat once more restored to its original state at a higher temperature and thus the process may be made continuous. The apparatus used for carrying this process into effect consists of a tube of porcelain or glazed earthenware inserted through a dome- furnace. The baryta is introduced in fragments into this tube at the entrance to which is placed a stopcock to regulate the access of air. To the other end of the tube are adapted two exit-tubes also furnished with stopcocks ;the one communicating with an aspirator the other with a gasometer. The tube is first raised to a dull red heat and the air made to pass through it by allowing the water to run from the aspirator; the baryta then becomes oxidised.After a certain time when the oxidation is thought to be sufficicntly advanced (it need not be complete) the stopcock which admits the air and likewise the stop- cock of the aspirator are closed and communication is established betwecn the tube and the gasometer. The temperature is then raised by opening the ash-door of the furnace and after a short time the oxygen which the baryta had absorbed is given off and passes into the gasometer. When the disengagement of gas is finished (and it is very rapid) the gasometer is closed the fire lowered by closing the ash-door and the aspirator again set in action. By this means the baryta is reoxidised and will then give up a fresh portion of oxygen on being more strongly heated; and these two operations may be continually repeated.The baryta in fact at a red heat acts * Ann. Ch. Phys. [3] XXX 5 ; Compt. rend. XXX 261 and 821. 270 BOUSSINGAULT ON THE EXTRACTION as a filter which retains the oxygen of the air and lets the nitrogen pass. In the course of the experiments made with this apparatus it was found that the baryta after having been used several times and occasionally even after the second operation lost in a great measure its power of absorbing oxygen. This diminution of absorbing power was equally apparent when the baryta was oxidised in a current of air carefully freed from water and carbonic acid and even when the oxidation was effected by a stream of pure oxygen; hence it was not due to any change produced in the baryta by carbonic acid water or other impurities in the air.It was for some time attributed to a partial fusion or vitrification taking place at the surface of the baryta in consequence of the presence of silica and alumina derived from the earthen vessels in which the baryta was calcined. More careful experiments however showed that with perfectly pure baryta calcined in platinum vessels the same diminution of absorbing power was apparent. The true cause of the diminution was ultimately found in the gradual but complete desiccation which the baryta undergoes by the continued passage of dry air over it. In fact &I.Boussingault's experiments show that pure anhydrous baryta has very little tendency to absorb oxygen; but that the hydrate when heated to dull redness in a current of air readily gives up its water and is converted into peroxide of barium.NOW, baryta prepared in the ordinary way is never perfectly dry; for though in calcining the nitrate any water that may be present is driven off by the heat the baryta nevertheless absorbs more or less water as it cools-more especially as in order to remove it from the crucible it is necessary to break it up. Now this partially hydrated baryta when first subjected to the action of the air at a low red heat absorbs oxygen with facility; but as its water is gradually abstracted its power of absorption becomes less and less. The easy conversion of hydrate of baryta into peroxide of barium by a current of dry air joined with the well-known fact that the peroxide is readily converted into the hydrate by boiling water or its vapour suggests the means of separating the oxygen of the air at a much lower temperature than by the process already described thereby econoniising fuel and avoiding the destructive action which the baryta exerts upon the earthenware tubes at high temperatures.In fact the decomposition of the hydrate and oxidation of the baryta take place at a dull red heat; and the decomposition of the peroxide by vapour of water may be effected at a still lower tem- perature viz. at 100"C. In carrying out this process however considerable difficulty was experienced from the extreme fusibility of the hydrate. This substance becomes liquid at a red heat; hence it was necessary to place it in a long silver boat occupying the whole length of the heated portion OF OXYGEN GAS FROM ATMOSPHERIC AIR.of the porcelain tube; but in a short time the crust of peroxide formed on the surface opposed so great an obstacle to the action of the air that the oxidation took place very slowly. This inconvenience was ultimately remedied by mixing the hydrate of baryta with hydrate of lime or with magnesia. The mixture is introduced into a porcelain tube and kept in its place by two plugs of asbestus. It is then oxidised by a rapid current of air the tube being kept at a dull red heat; and when the oxidation has proceeded far enough the connexion with the gasometer is established and a jet of steam introduced into the tube from a small boiler disposed for the purpose.The peroxide of barium is then immediately reconverted into hydrate of baryta and the excess of oxygen is given off. The baryta is then reoxidised by a fresh current of air again deoxidised by vapour of water and thus the process is made continuous. Baryta thus treated appears to retain its power of absorbing oxygen for any length of time. In the process just described we have perhaps an example of the influence of mass in chemical decomposition. In the one case a large quantity of air expels the water from hydrate of baryta and puts oxygen in its place; in the other at the same temperature a continuous current of vapour of water expels the oxygen from peroxide of barium and reconverts it into hydrate of baryta.This mode of extracting oxygen from the air has hitherto been used only in laboratory experiments; but there appears to be no reason against its use on the large scale. In fact 10 kilogrammes of baryta if completely oxidised and deoxidised will yield 730 litres of oxygen gas; and even supposing that for the sake of quickness of operation this quantity were reduced to 600 we might by operating on 100 kilogrammes of substance heated in eight or ten cylinders obtain at each deoxidation 6000 litres of oxygen; and supposing four or five such operations to be gone through in four-and-twenty hours the product would be from 241,000 to 30,000 litres of gas (OF in English measures from 5000 to 6000 gallons of gas from 8 or 9 cwt.of baryta). As baryta is now prepared in large quantities its use would not present any difficulty; but in order that the process may be advan- tageously conducted on the manufacturing scale there are still many points to be determined. Thus it would be necessary to determine the manner in which the oxidation is affected by the velocity of the current of air and whether it would not be advisable to use hot air in order to accelerate the operation and avoid loss of heat. The necessity for the presence of water in the oxidising process may be considered as established ; but it still remains to determine the quantity of vapour which the air should contain in order to act to the greatest advantage FREMP ilND BECQ.UEREL ON THE EIectro-Chemical Researches on the Properties of Electrified Bodies.* By E. Fremy and E. Becquerel. For some years the attention of chemists has been directed to the singular modifications which certain bodies present when submitted to the action of a moderately elevated temperature. It is known for example that sulphur and phosphoruq when thus treated acquire new properties. The authors propow to examine in a aeries of memoirs whether electricity is capable of altering the physical and chemical characters of bodies in a similar manner to heat; and have in the first place directed their attention to the remarkable effects presented by oxygen under certain circumstances and commonly attributed to the formation of a peculiar principle called Ozone.This body appears in fact to be produced whenever oxygen is subjected to electrical influence; but its production or the effects attributed to it take place in different degrees according to the kind of electricity employed. 1. The voltaic battery cannot be used for determining the nature of ozone because the amount of the active principle existing in the oxygen thereby obtained is very small. 2. The arc formed on breaking the voltaic current does not appear to modify oxygen in the same manner as the ordinary spark probably because the rise of temperature which accompanies it destroys what the electricity might produce. It appears however that the voltaic arc is capable of inducing the combination of gases acting in fact like spongy platinum or the common electric spark.The authors have by nieans of the voltaic arc induced the direct combination of nitrogen with oxygen to form nitric acid; of hydrogen with iiitrogen to form ammonia; and of sulphurous acid with oxygen to form anhydrous sulphuric acid. 3. The spark proceeding from induced currents and produced by means of the apparatus lately constructed by &I. Ptuhmkorf acts like the spark of the ordinary electrical machine and enables the operator to repeat without fatigue all the experiments which can be made with the machine. 4. Pure oxygen enclosed in glass tubes together with a strip of paper saturated with starch and iodide of potassium niay be electrified by induction by means of a succession of sparks passing along the external surface of the tube; the paper begins to turn blue after the passage of a few sparks.This colouring is due to the electrization of the oxygen and not to any electrolytic decomposition of the iodide; for when the experiment is made in an atmosphere of hydrogen no blueing is produced. This fact is the more remarkable inasniuch as * Ann. Ch. Phys. [3] XXXV 62 ; abstr. Compt. Rend. XXXIV 399 ; J. Pharm. [S] XXXI 321. PROPERTIES OF ELECTRIFIED BODIES. the oxygen is electrified without the intervention of metallic wires and consequently when there can be no transference of particles by the spark. 5. Oxygen prepared by the most various methods e. g. by calcining the oxides of manganese mercury and silver by the decomposition of chlorate of potash and by the electrolysis of water acquires a peculiar odour and very decided oxidating powers when subjected to the influence of electricity ;these properties are exhibited by oxygen in the greatest state of purity obtainable.Oxygen thus electrified loses its oxidating properties when placed in contact with iodide of potassium; but its odour and oxidizing powers may be restored by fresh electrization ; this experiment may be repeated any number of times with the same gas. These facts show that the oxidating power of electrified oxygen is not due to the presence of any foreign substance in the gas. The following experiments were made for the purpose of rendering a given volume of oxygen totally absorbable in the cold by mercury silver or iodine of potassium.6. When pure dry oxygen gas is enclosed in a series of glass tubes and submitted as above to the action of the electric spark and one end of each tube then broken to find how much of the gas has been rendered capable of absorption by the alkaline iodide it is found that for several hours the modification increases in proportion to the time of electrization and afterwards appears to diminish probably because the spark destroys that which it had before produced. 7. The difficulties attending the preceding experiment induced the authors to study the action of electrized oxygen on certain absorbing substances capable of immediately taking up the oxygen which has been subjected to the action of electricity and thereby removing it from the decomposing action of an excess of that agent.A series of electric sparks was therefore passed through small eudiometric tubes filled with oxygen and either placed over moist mercury or a solution of iodine of potassium or having a moist silver plate introduced into them. The oxygen was then regularly absorbed under the influence of the electric spark and in several experiments complete absorption took place. 8. Finally to remove all doubts respecting the particular activity imparted to oxygen by the electric spark the preceding experiments were repeated with sealed tubes. For this purpose iodide of potassium and moist silver were introduced into tubes filled with pure oxygen and the tubes were then sealed.These tubes were subjected for several days to electric action ; the spark which was very brilliant at first becanie paler and paler; and after a while nearly invisible. The ends of the tubes were then broken under water whereupon the water rushed in and filled them corn- VOL. V.-NO. XIX. T VOLCKEL ON THE PREPARATION OF pletely showing that the oxygen had been entirely absorbed in the cold by the silver and by the alkaline iodide. To reuder these experiments decisive it was previously ascertained I. That the oxygen is not absorbed by pure water by the sides of the glass vessel or by the platinum wires; 11. That the presence of water is required not to develop the activity of the oxygen but to enable the active oxygen to act on the metals and the alkaline iodide; 111.That the electric spark does not decompose iodide of potassium by influence. The experiments above described may be considered as affordizig rigorous proof that oxygen may by the influence of electricity be rendered wholly absorbable at ordinary temperatures by iodide of potassium and by several metals-mercury and silver for example. They likewise confirm the latest results obtained by Schonbein Marignac and De la Rive respecting the nature of the so-called ozone and show that electricity by acting upon oxygen develops new properties which did not exist in it before. The authors therefore propose to give the name of Electrixed Oxygen to the gas thus modified by electric influence and to abandon the term Ozone which gives the idea of the transformation of the oxygen into another body.On the preparation of pure Acetic Acid from Wood-Vinegar and Brandp-Vinegar." By C. Volekel. The ordinary mode of preparing pure acetic acid from wood-vinegar viz. by converting the latter into acetate of soda freeing this salt from empyreumatic substances by roasting and fusion and then decomposing it by sulphuric acid is both tedious and expensive in consequence of the roasting and repeated crystallizations required ; consequently the acetic acid thus obtained cannot be economically used for the preparation of pure acetate of lead that salt being in fact obtained much more cheaply from brandy-vinegar. Various attempts have therefore been made to purify the acetic acid in wood- vinegar at a cheaper rate; and for this purpose the author proposes the following process consisting essentially in the conversion of the crude acid into acetate of lime and the decomposition of that salt by hydrochloric acid.To obtain acetate of lime in a sufficient state of purity the crude acid is saturated with lime without previous distillation whereupon a part of the resinous impurities separate out in combination with lime while the rest remain in the liquid imparting to it a dark * Ann. Ch. Pharm. LXXXII 49. ACETIC ACID FROM WOOD AND BRANDY VINEGARS. 275 brown colour ;and the liquid is clarified by filtration or by simply leaving the impurities to settle down and afterwards evaporated in an iron pot to about one half its bulk.Hydrochloric acid is then added in such quantity that a small sample of this liquid may dis- tinctly redden litmus after cooling. This causes the dissolved resin to separate and collect together in the boiling liquid so that it can easily be skimmed off-and likewise decomposes the lime-compounds of creosote and other volatile substances which may then be expelled by further evaporation. The quantity of hydrochloric acid required for this purpose varies of course with the constitution of the wood- vinegar which again varies with the degree of moisture of the wood from which the acid is obtained ;but the average quantity is from 4 to 6 pounds for 150 litres (33 gallons) of the wood-vinegar. The solution of acetate of lime is then further evaporated and ultimately dried at a high temperature to drive off all volatile substances.The evaporation and drying may generally be performed in the same iron vessel; but in operating on a very large scale it is best to dry the salt on cast-iron plates the drying requires the greatest care. The volatile empyreumatic substances adhere very tenaciously to the acetate of lime and to the resin contained in it and unless driven off by heat they pass over in the subsequent distillation together with the acetic acid and impart to it a bad odour. The drying must therefore be continued till the acetate of lime becomes inodorous or nearly so. When thoroughly dried it has a dirty-brown colour. To obtain the acetic acid from this salt it is distilled with hydro- chloric acid.The distillation may be performed in a still with copper head and leaden condensing-tube; if the operation be con-ducted with proper care neither copper nor lead is found in the distillate. The quantity of hydrochloric acid required cannot be exactly given because the acetate of lime contains variable quantities of foreign matters viz. resin and chloride of calcium already formed. In general however from 90 to 95 parts of hydrochloric acid of 20' Baum6 or sp. gr. 1.16 will completely decompose 100 parts of acetate of lime without causing the distillate to be much contaminated with hydrochloric acid. In any given case the quantity of hydrochloric acid required is easily determined by an experiment on a small scale. The apparatus may likewise be so arranged as to allow of the subsequent addition of hydrochloric acid in case of the quantity first put in being found insufficient.Whether the quantity introducedis sufficient may be known by testing the distillate with nitrate of silver ;so long as mere turbidity is produced we may be sure that the hydrochloric acid is not in excess. The distillation of the acetic acid proceeds with ease and regularity. The acetate of lime dissolves in the hydrochloric acid forming a dark-coloured liquid while a quantity of coloured resin separates out. As the whole mass is liquid the heat diffuses through it easily; and T2 276 VOLCKEL ON THE PREPARATION OF as the acetic acid passes over between 100" and l2Oo and the acetate of lime has been already exposed in drying to a higher temperature the distilled acid is but very slightly contaminated with empyreumatic products resulting from decomposition of the resin.illoreover the resinous matters being lighter than the chloride of calcium solution float on the top and do not form hard incrustations in the still. The distilled acetic acid has but a very slight ernpyreuniatic odour which is also very different from that of crude wood-vinegar. It is perfectly colourless and if the hydrochloric acid has not been added in excess gives but a slight cloud with nitrate of silver. Any yellow tint that it may exhibit arises from particles of resin mechanicalIy carried over; for the resin separated from the acetate of lime by the hydrochloric acid melts as the temperature rises and forms a fluid layer on the surface of the chloride of calcium solution which is very apt to cause spirting.The resin should therefore be moved as far as possible before distillation either by skimming it off with a spoon or by filtering through a linen cloth. The specific gravity of the acetic acid obtained by this process varies from 1.058 to 1.061 corresponding nearly to 8" Baum6 or 10' Beck It contains more than 40 per cent of anhydrous acetic acid. As however acetic acid of this degree of concentration is rarely used and a somewhat weaker acid is more easily separated by distillation from the solution of chloride of calcium it is better to add a certain quantity of water either before or towards the end of the distillation.A good proportion is :-lo0 parts acetate of lime from 90 to 95 of hydrochloric acid and 25 of water. This gives from 95 to 100 parts of acetic acid of 7" Baun16 or sp. gr 1.105. In this manner 150litres of wood-vinegar will yield 60 pounds of acetic acid of this strength. The acetic acid thus obtained may be still further purified by mixing it with a small quantity of carbonate of soda and distilling it again. The acid which passes over is free from hydrochloric acid and perfectly colourless but still retains a slight empyreurnatic odour. But even this may be removed by distilling it with 2 or 3 per cent of bichromate of potash instead of carbonate of soda. Acetic acid purified with bichromate of potash is in fact undis- tinguishable from that which is obtained from pure acetate of soda by distillation with sulphuric acid or from pure acetate of lime with hydrochloric acid.It does not exhibit the slightest colour when heated with strong sulphuric acid nor does it reduce the smallest quantity of silver when boiled with nitrate of silver and ammonia. When saturated with oxide of lead it also yields a colourless salt the analysis of which agrees perfectly with that of pure acetate of lead. Peroxide of manganese may also be used for the purification instead of bichromate of potash; but the acid thus purified gives after a while a slight turbidity with nitrate of silver ;any empyreu- -4CETIC ACID FROM WOOD AND BRANDY VINEGARS. 277 matic odour that it may retain may be removed by digestion with purified animal charcoal.As the acetic acid can be so easily freed from hydrochloric acid a slight excess of the latter during distillation is not injurious; on the contrary the presence of a small quantity of hydrochloric acid is very useful for the purification of the acetic acid with manganese 01' bichromate of potash. The rectification of acetic acid with bichromate of potash or with manganese may be very well conducted in a copper still with leaden condensing tube the acid thus prepared can only be contaminated with a small quantity of acetate of lead. If however access of air be prevented* during the distillation this impurity will be confined to the first and last portions of the distillate; and by collecting these apart to be used for the preparation of acetate of lead the greater part of the acid may be obtained free from lead.With these precau- tions the use of glass or silver heads and condensing tubes may be dispensed with. The preparation of acetic acid by the method just described may be rendered simpler by subjecting the wood-vinegar to a previous distillation and thereby removing the greater part of the resin. But this previous distillation entails increased expense for labour and fuel because the same liquid must be twice evaporated; moreover part of the acetic acid remains with the tar in the still. On the small scale the loss thus occasioned is unimportant; but in a large manufac- tory it would amount to something considerable in the course of a year.The expense occasioned by previous distillation of the wood-vinegar may be avoided by the use of a compound still. The vapour of the wood-vinegar instead of being condensed immediately is made to pass into a copper receiver containing the quantity of lime required to saturate the acid which is thereby completely absorbed. If the copper receiver be surrounded by some substance which is a slow conductor of heat but little aqueous vapour condenses in it. This vapour may be advantageously used to evaporate a solution of lime resulting from a previous operation. This process is however more complicated and does not yield more acetic acid than the simpler one first described. The method here recommended is much cheaper and yields a much purer product than the ordinary method of distilling impure acetate of lime with sulphuric acid.Moreover by the addition of hydrochloric acid during the evaporation of the impure acetate the volatile slightly acid bodies contained in the wood-vinegar are removed much more easily than by the use of a solution of chloride of calcium (Schnedermann) or by roasting the impure acetate of * The entrance of air into the condensing-tube may be prevented by closing the end of the tube with a cork through which is inserted a glass tube bent in the form of an S. 278 ON ACETIC ACID FROM WOOD AND BRANDY VINEGARS. lime either alone or with hydrate of lime (Kestner Scbwarz). In the latter process even if it attains the desired end a consi-derable loss is incurred from decomposition of the acetate of lime inasmuch as that substance from its infusibility does not admit of any exact regulation of the heat.The use of hydrochloric instead of sulphuric acid in the decompo- sition of the acetate of lime has this great advantage that the pre- sence of resins colouring matter &c. in the acetate of lime does no harm provided the acetate has been sufficiently heated to drive off these free volatile substances. When on the contrary sulphuric acid is used the acetic acid produced always has a bad odour is saturated with sulphurous acid and contaminated by various products arising from the decomposition of the resins at an elevated tem- perature. Moreover the sulphate of lime forms a hard crust at the bottom of the still and in distilling on the large scale the bottom of the still must be heated red-hot to drive out all the acetic acid.The last portions of acid that pass over are often turbid from the presence of separated sulphur; and the odour of sulphuretted hydrogen becomes perceptible that substance arising from reduction of the sulphate of lime to sulphide of calcium at the bottom of the vessel from this cause cast-iron stills soon become corroded. The low price at which pure acetic acid may be obtained by the method above described ~lll probably lead to a more extended use of it in dyeing and calico printing. The acid thus obtained may like- wise be advantageously used in the preparation of acetates especially of acetate of lead.Pure Acetic Acid from Brandy- Vinegar. A similar process may be adopted for the preparation of pure acetic acid from brandy-vinegar ;the process however is simpler inasmuch as brandy-vinegar is much less impure than wood-vinegar. Strong brandy-vinegar (the best for this purpose is that which contains from 12 to 15 parts of anhydrous acetic acid-a proportion which is obtained in some manufactories by a process at present not much known) is saturated with lime ;and the turbid and coloured solu- tion is strained through a linen cloth and evaporated to dryness in an iron vessel. The dried salt is perfectly white the colouring matters previously contained in the solution having been for the most part destroyed by the oxidizing action of the air. The decomposition of the acetate of lime is effected by hydro- chloric acid in the manner already described excepting that the acetate of lime being less mixed with foreign matter than that obtained from wood-vinegar a larger proportion of hydrochloric acid is required for its decomposition viz, about 130 parts of acid to 100 parts of the lime-salt.The final purification of the acid may be effected by either of the methods above described DELFFS ON CENANTHIC ETHER AND CENANTHIC ACID. 279 On llEnanthic Ether and CEnanthic Acid.' By W. Delffs. CEnanthic ether was first investigated in 1836 by Liebig and Pelouze,? who assigned to it the formula C18 H18 03-,C4 H5 0.c14 H13 02 relying in the calculation of their analyses chiefly on the vapour- density; this they found to be 10.508 a result agreeing very closely with calculation assuming that the vapour was condensed to two volumes.At present however organic compounds in general and the ethers more especially are regarded as condensed to 4 volumes so that enanthic ether considered as above presents an anomaly which throws some doubt on the correctness of the calculation more especially as compounds of purely organic origin rarely have so high a vapour-density as that just quoted. Moreover the formula HI3 O2can scarcely be the correct expression of the composition of anhydrous enanthic acid; first because it would require us to suppose that in the lead and silver-salts 3 atoms of acid are united with 2atoms of base which is very unusual in organic acids ; and secondly because the occurrence of an acid with only 2 atoms of oxygen is scarcely to be found in the whole range of organic chemistry certainly not among the fatty acids Lastly the relation between the composition and boiling points of organic compounds shows that the composition of cmanthic ether must be different from that which is given by Liebig and Pelorxze.These considerations induced the author to submit this body to a further examination which led to the following results. 1 (Enanthie Ether.-The substance employed had a yellowish colour and feebly acid reaction. When subjected to fractional dis-tillation it began to boil at 240O C. The temperature then rose steadily to 246' where it began to be stationary. The receiver was then changed and the distillation continued for two hours during which time the thermometer did not rise above 250'.The liquid which passed over during this interval amounting to nearly the fourth part of the crude ether was used in the followingexperiments. It was perfectly colourless but still slightly acid; it was therefore washed with solution of carbonate of soda dried by chloride of calcium and rectified. When the ether thus purified was used for the determination of the boiling-point it again acquired a yellowish tinge; and when boiled over a spirit-lamp either with or without platinum wire exhibited a very peculiar phenomenon bubbles of vapour bursting from the * Pogg. Ann. LXXXIV 505. f-Ibid. XLI 571. 280 DELFPS ON (ENANTHIC ETHER AND (ENANTHIC AClD.liquid from time to time with a noise as if the retort were cracking and giving rise each time to a visible cloud of condensed vapour. This phenomenon was not exhibited when the ether was heated on a sand-bath. It differed from the well-known sudden agitation which many liquids present in boiling by not causing any perceptible interruption to the quiet progress of the ebullition. After the ether had been rectified a second time when a yellowish residue again remained this effect was but very slightly exhibited though the boiling-point differed from the former by scarcely half a degree. The ether thus purified was colourless had a pleasant vinous odour and a taste slight at first but afterwards irritating to the throat Sp.gr. = 0.8725 at 15.5’ C. Index of refraction = 1.414 at 13.5’ C Boiling-point very constant at 224’ under a pressure of 27” 8’”*1,with the mercury at a temperature of 14’. The analysis of the ether with oxide of copper gave carbon 70.5 and 70.6 per cent ;hydrogen 11.8 numbers agreeing very closely with the formula C22H22O*. The vapour-density was found by experiment to be 7,042;calculation from the formula C22 H22O* gives 6.449 The difference is somewhat greater than is desirable but is suffi-ciently accounted for by the impossibility of heating the vapour to the necessary temperature above the boiling-point without decom- posing it. CEnanthic Acid.-CEnanthic ether is rapidly decomposed by heating it with caustic potash; and on subsequently adding hydro- chloric acid to the solution oenanthic acid separates in the form of a slightly yellowish oil which solidifies on cooling in a snow-white mass showing scarcely any traces of crystallization.It is readily dissolved by alcohol even in the cold and in almost every proportion by ether ; from the alcoholic solution it separates by spontaneous evaporation as a crystalline mass. When pure it is perfectly destitute of taste and smell and melts even with the heat of the hand. The accurate determination of the melting-point is diacult as the acid passes into a buttery state before melting but it is certainly below 25’ C. The acid dissolves easily in ammonia forming a solution which dries up even on spontaneous evaporation to a greasy soap which does not again form a clear solution in water.The solution of the ammoniacal salt made as neutral as possible formed with nitrate of silver a white curdy precipitate which did not dissolve perceptibly in boiling water. This salt when thoroughly washed and dried gave on analysis numbers corresponding with the formula Ago . C, H17 0 or C, f: 0 The composition of the hydrated acid must therefore be C, H, 0, a formula with which the analysis made by Liebig and Pelouze agrees PELOUZE ON SORBINE. sufficiently well when their results are calculated according to the atomic weight of carbon at present adopted. From this it appears than aenanthic acid is identical in compo- sition with pelargonic acid as analyzed by Redtenbacher and Pless.* The two acids appear also to be similar in properties so far at least as Redtenbacher has determined those of pelargonic acid.The identity in composition was likewise confirmed by the analysis of the baryta-salt of cenanthic acid. Pelargonate of baryta is said by Redtenbacher to resemble the crystals of cholesterin. Such a resemblance was not observed in the aenanthate; but its absence is of little importance as the author has on other occasions observed considerable differences in the appearance of crystals of butyrate of baryta though they are always as Lercht states perfectly an- hydrous. There is one point in Liebig and Pelouze’s investigation which must for the present be left undecided viz. the change which cenanthic acid undergoes by distillation.This the author was unable to investigate properly for want of material ; but the portions which passedover at a high temperature appeared to contain an acid having a higher equivalent (capric acid 1). In a note appended to this paper the author states that the con-version of organic baryta-salts into carbonate of baryta by ignition in a flat platinum dish affords a very convenient mode of sscertain-ing the atomic weight of an organic acid. On Sorbine a new saccharine substance extracted from the berries of the Mountain Ash.$ BY J. Pelonze. The berries of the mountain ash contain amongst other substances malic acid malate of lime and grape-sugar; their great acidity forbids the supposition that they contain ordinary cane-sugar ; but Pelouze has succeeded in obtaining from them a sugar differing in many essential properties from any of the sugars previously known.The berries gathered towards the end of September were crushed and squeezed through linen. The juice thereby obtained was left to itself in earthen vessels for thirteen or fourteen months during which time it yielded deposits and vegetations which were not examined. The liquid which at length clarified spontaneously was decanted and then evaporated at a gentle heat to the consistence of a thick syrup. This syrup deposited a quantity of dark-brown * Ann. Ch. Pharm. LIX 52. t. Ibid. XLIX 216. $ Ann Ch. Phys. [3] XXXV 223 ; J. Pharm. [3] XXI 321. PELOUZE ON SORBINE. crystals which were completely decolourized by treating them twice with animal charcoal.By successive concentration of the mother- liquid fresh quantities of crystals were obtained and purified in a similar manner. The crystals thus contained consist of a new substance to which the author gives the name of SORBINE,By analysis they yielded in 100 parts carbon 40.00 hydrogen 6-66; oxygen 53.34 agreeing with the empirical formula CHO. The numbers have been confirmed by MM Cahours and Cloez to whom a specimen was sent for analysis. To determine the rational formula a solution of acetate of lead slightly ammoniacal was added to a solution of sorbine in excess; a white precipitate was then formed which when washed and dried yielded by analysis numbers which agreed nearly with the formula 4 PbO.C, H 0,. Hence it would appear that the formula of aqueous sorbine is C, H 0 . 3 HO or C, HISO,,. Sorbine combines with common salt forming crystals which when examined by the microscope appear to be cubic. Sorbine is colourless and has a pure sweet taste which cannot be distinguished from that -of cane-sugar. The crystals are perfectly transparent hard and grate between the teeth like sugar-candy. They are rectangular octohedrons belonging to the right prismatic system. Their density at 15' is 1.654. Water dissolves more than twice its weight of them ;boiling alcohol on the contrary dissolves but a very small quantity which it deposits again on cooling in octohedral crystals similar to those which are obtained from the aqueous solution.A concentrated solution of sorbine resembles the syrup of ordi-nary sugar. Its density determined upon a liquid which was not quite pure was 1.372 at 15O. Both sorbine itself and the syrup which it forms with water are somewhat denser than cane-sugar and its syrup. Sorbine dissolved in water and mixed with yeast showed no signs of fermentation even after twenty-four hours' exposure to a tem-perature of 20'-30° C. Dilute sulphuric acid produces no change in it and does not render it fermentable. Strong sulphuric acid attacks sorbine rapidly first colouring it reddish-yellow and then under the influence of a gentle heat changing it into a black carbonaceous substance which the author has not yet examined. When nitric acid either concentrated or diluted with half its weight of water is heated with sorbine abundance of red fumes are given off and oxalic acid is produced! equal in weight to more than half the sorbine used; in fact the action is perfectly PELOUZE ON SORBINE.similar to that which takes place with cane-sugar. The author has not yet determined whether any intermediate product is formed. A solution of sorbine heated with alkalies acquires a deep yellow colour and exhales an odour of caramel. Water containing of sorbine becomes perceptibly yellow when heated with potash. Sor-bine dissolves a considerable quantity of lime. The filtered liquid turns yellow when heated depositing a flocculent precipitate and giving off a distinct odour of caramel. Baryta acts in the same manner as lime.Oxide of lead also dissolves in a hot solution of sorbine forming a yellow liquid which has the odour of burnt sugar. Sorbine yields no turbidity with subacetate of lead but on the addition of ammonia a white precipitate is formed. Sorbine dissolves hydrated protoxide of copper forming a deep blue solution which gradually deposits a red precipitate of the sub- oxide. Tartrate of copper and potash is also reduced by sorbine either hot or cold. Sorbine strongly heated on platinum-foil or thrown upon a hot coal behaves like common sugar fusing turning yellow exhaling a strong odour of caramel and leaving a bulky charcoal. But when it is carefully heated for some time to a temperature between 150" and 180' C. it gives off vapour of water slightly acid and is converted into a new acid which remains in the form of a deep-red body.To obtain this acid pure the residue is dissolved in potash or ammonia the solution filtered and supersaturated with dilute hydro- chloric acid. The acid is then precipitated in deep-red flakes which are washed with distilled water and then dried in a stove at a tem- perature between 120' and 150'. The author distinguishes this new acid by the name of SORBIC ACID. Sorbic acid is amorphous of a very deep-red colour insoluble in water alcohol and weak acids but very soluble in potash soda and ammonia with which it forms solutions having a very rich sepia colour. A mere trace of sorbic acid is sufficient to impart a sensible colour to an alkaline liquid.The soluble salts of lime baryta alumina iron tin gold and platinum form with soluble sorbates bulky precipitates exhibiting reddish-yellow colours of various degrees of intensity. Sulphate of copper yields a yellowish-green precipitate soluble in excess of ammonia to which it imparts a very deep-green colour. Sorbic acid is found by analysis to contain carbon 57-96; hydrogen 5.51 ; oxygen 36-53;and the sorbate of lead consists of 51-35 oxide of lead with 48.65 sorbic acid. Hence if the for-mula of sorbic acid be C32 HI* 015 that of the lead-salt will be 3~bo.c32 ~18 015. Sorbine acts upon polarized light ;when dissolved in water or in acids it turns the plane of polarization to the Zejt ;in this respect 284 PEBAL ON THE it differs from other crystallizable sugars all of which turn the plane of polarization to the right.On the Constitution of Citric Acid." By L. Pebal. The author commences his paper with a sketch of the principal views which have been entertained respecting the constitution of citric acid dwelling chiefly on those of Berzelius and Liebig. Berze-liust regarded citric acid as monobasic assigning to the acid con- tained in the neutral citrates the composition C H 0,. This view rested chiefly on an experiment from which it appeared that the crystals obtained by cooling a solution of citric acid saturated at 100' C. had the composition HO .C H 0, and clidnot give off any water when heated to 100'. On the contrary the crystals obtained from a solution saturated at ordinary temperatures lost at ZOO' a quantity of water which if their composition were denoted by the formula HO .c6 II O6+Aq.$ would arnount to one equivalent ; hence the last-mentioned crystals if referred to the atomic weight of citric acid first given would contain after dehydration & eq.of' water less than the crystals obtained from the hot solution likewise dried at 100'. Liebig,§ on the contrary regards the acid as terbasic and expresses the several compounds just mentioned by the following forniuh 3 HO .C, H O,,+2 Aq=acid crystallized from a solution satu- rated at ordinary temperatures. 3 HO .C, H Oil+ Aq=crystals obtained by Berzelius from a hot saturated solution. 3 HO .C, H O, =the first compound dried at 100' C.The second formula is evidently equivalent in numbers to that of Berzelius HO .C1 H 0,. taken three times; if however it be cor- rect one-fourth of the water that namely which is supposed to exist as water of crystallization should go off at 100' C. whereas accord- ing to Berzelius it does not. Marchand,lj however found that the crystals obtained from a hot saturated solution gave results agreeing with the formula HO .C H 0, only when analyzed immediately after removal from the mother-liquor ; but that when they were left for a. while in vacuo over sulphuric acid they gave off 2.2 per cent of water without losing their transparency and their composition then agreed exactly with that of ordinary citric acid dried at loo' viz. * Ann.Ch. Pharm. LXXXII 78. t Pogg. Ann. XXVII 281 ; Ann. Ch. Pharm. V 129 134 137. $ Prout. Pogg. Ann. XII 271. 0 Compt. rend. V 863 ;Ann. Ch. Pharm. XXVI 113. {I J. pr. Chem XXIII 60. CONSTITUTION OF CITRIC ACID. 3 HO .C, H Oil. The excess of water which the crystals contain on being first separated from the liquid can therefore only be regarded as adhering moisture. This result has been completely con- firmed by the experiments of Yebal. Liebig's view of the constitution of citric acid is likewise con- firmed by the formula of citric ether as determined by Dumas," viz 3 Ae 0 .C, H 011, and by those of the citrates of methyl determined by Evre,? viz. 3 Me0 ,C, H Oil and 2MeO. HO. C, H Oil. The following experiments of Pebal on the anilides of citric acid likewise tend to establish the terbasic formula.Crystallized citric acid in the state of powder was mixed with a slight excess of aniline containing water (i.e. in the state in which it sepa- rates as an oily body under water) and heated in a glass flask to 140'-150' C. till the emission of vapour-bubbles began to slacken. On cooling it solidified to a brown-red glass which was exhausted with boiling water ; and the residue which meanwhile had assumed the form of a pale yellow powder was dried dissolved in strong alcohol and decolourized with animal charcoal. The aqueous extract after evaporation deposited a small quantity of an acid crystalline mass consisting of citromonanilic acid a sub-stance to be hereafter described.The alcoholic solution yielded crystals of three different substances two of which had the form of thin prisms and the third that of hexagonal tables. Of the two kinds of prismatic crystals the one became dull and opaque when left to stand over sulphuric acid covered by a bell-jar while the others remained unaltered under the same circumstances. The largest portion of these crystals consisted of Citronanilide C, H, N O,.-This substance is insoluble or very sparingly soluble in water ;sparingly also in boiling alcohol from which it crystallizes by spontaneous evaporation in flat colour- less rectangularly truncated prisms attaining the length of' about 3 millimetres. They are sometimes very slender generally arranged in concentric masses longitudinally striated and have a mother-of- pearl lustre.Their solution has no action on vegetable colours. Strong solution of potash or ammonia does not decompose the crys- tals and may therefore be used to purify them from the six-sided tables which are dissolved by the strong alkali. This substance may be regarded as terbasic citrate of aniline minus 6 HO. C, H N .HO C, H N. HO C12H,0,,-6 HO=C, W9 N3 0, C, €3 N. HO I Citrobianil C, HI6 N 0,. -The six-sided lamins already spoken of. Probably the best mode of preparing this compound by * Compt. rend. VIII 528. * Ibid. XXI 1441. 286 PEBAL ON THE itself would be to mix citric acid with aniline in the proportion required to form a bibasic salt and heat the mixture to 150° C. as long as any perceptible evolution of hydrogen took place.The coloured crystals may be purified by treating their alcoholic solution with animal charcoal and recrystallizing. The solution of the pure substance which does not alter the colour of litmus-paper yields by spontaneous evaporation six-sided lamin8 or tables of the diameter of about 5 millimetres. They are transparent and dissolve very sparingly in water but easily in boiling alcohol. By boiling with strong ammonia they are converted into citrobianilic acid. The crystals after drying in the air do not lose weight by being kept over sul- phuric acid. Citrobianil may be supposed to be formed from bibasic citratedof aniline by separation of 6 HO C12H N. HO C12 H N HO 1C12 H5011-6 HO=C, Hi6 N2 0,.HO The four-sided obliquely -truncated needles which were obtained simultaneously with the citronanilide and citrobianil and distin- guished by the property of efflorescing when placed over sul-phuric acid lost at 100' about 1.08 per cent of their weight after drying in the air. They were found to contain 66-71 per cent carbon and 5.0 per cent. hydrogen numbers which agree exactly with the composition of citrobianil; but the quantity obtained was not sufficient to enable the author to speak positively as to their identity. Citrobianilic Acid c36HISN o, or HO .c36 H, N O,.-When citrobianil is boiled with strong ammonia it gradually dissolves and is converted into the ammonia-salt of citrobianilic acid. The solution mixed with hydrochloric acid deposits the acid in the form of a curdy precipitate which is soluble in alcohol ; and the alcoholic solution which reddens litmus yields the acid in soft silky needles radiating from several centres ; they dissolve readily in alcohol but sparingly in water.The acid melts at about 153O giving off water and being converted into citrobianil. It may indeed be regarded as formed from citrobianil by taking up 2eq. water c36 H16 N2 05$+2HO=CC36 N O10 and its composition is that of bibasic citrate of aniline minus 4HO. CI2H5 01,-4 HO HO Citrobianilate of Silver Ago .c36 H17 N Oq was obtained by mixing a neutral solution of the acid in ammonia with nitrate of silver ; CONSTITUTION OF CITRIC ACID. 287 it formed a white precipitate.The Baryta-salt Ba 0 C, HI N 09 was obtained in a similar manner by double decomposition in the form of a white amorphous precipitate. The Aniline-salt C, H N .HO ,C, H N 0, was obtained by digesting the acid at a moderate heat with aqueous aniline. On evaporating the solu- tion the salt was deposited in colourless transparent lamina? which suffered very little diminution in weight by drying over sulphuric acid. The composition of these salts show that the acid is monobasic Monobasic Citrate of Aniline.-An alcoholic solution of citric acid was mixed with the proper quantity of aniline containing a little water and the mixture left in vacuo over sulphuric acid till it dried up to a viscid brown-red mass. After some time crystals began to form in it and ultimately filled the whole mass.The whole was then triturated with a small quantity of alcohol the liquid pressed through linen the solid residue dissolved in strong alcohol and the solution left to evaporate over sulphuric acid. The salt was then obtained in fine needles united into geodes. They fuse at looo dissolve readily in alcohol and still more readily in water. Sometimes after the mother-liquor has been poured off the fine needles form a kind of frothy mass The composition of this salt may be expressed by the formula The two other aniline-salts show no tendency to crystallize. Monobasic Citromonanilic Acid C2* H NO,,.-When the salt just described is fused at a temperature of 14@0-1500 water escapes and the residual mass solidifies partly while hot and partly on cooling to a crystalline body which dissolves very easily in water provided an excess of aniline has been avoided and separates by spontaneous evaporation partly in crystalline globules but more abundantly in the form of warty crusts consisting of small prisms.They may be rendered colourless by treatment with animal charcoal and recrystal- lization. They are likewise easily dissolved by alcohol ;their solutions redden litmus-paper. The acid may be regarded as monobasic citrate of aniline minus 4 HO Xiher-salt Ago. C, H, NO,.-An alcoholic solution of theacid neutralized with ammonia gave a white precipitate with nitrate of silver. The liquid separated from this precipitate yielded after a while crystalline globules which when freed from a small quantity HOFRlANN ON TRIMETHYLAMINE.of pulverulent matter adhering to them were found to have the com- position above given. Aniline-salt C1 H N .HO .C, H, NO,.-Formed by satu-rating the aqueous solution of the acid with aniline. Spherical geodes easily soluble in alcohol. Silver-salt of Bibasic Citromonanilic Acid.-The white precipitate obtained in the preparation of the silver-salt of the monobasic acid. Its composition is expressed by the formula 2 Ag 0 .C, H, NO,,. It was found impossible to obtain the hydrate of thiqacid on account of its strong tendency to decompose. Its formula would be 2 HO. C, €I, NO,,=C, H, NO,,. On the occurrence of Trimethylamine in Herring-brine." By Dr. Hofmann.In the course of some observations on the ammonias of the methyl- series,? Dr. Hofmann has suggested that the base described by Wertheim under the name of Gnylamine or Propylamine may be identical with trimethylamine (H,H,C,H,) N=C6H,N=3(C,H,).N. The interesting observation likewise made by Werth eim that the so-called propylamine exists in considerable quantity in herring-brine has afforded an opportunity of putting this question to the test of experiment. At Dr. Hofmann's suggestion the subject has been examined by Mr. Henry Winkles from whose experiments it appears that the principal constituent of a mixture of bases contained in herring-brine is actually Trirnethylamine. The base was identified both by comparison with trimethylamine synthetically prepared and by its behaviour with iodide of methyl.With the latter it instantly solidified into a crystalline mass of iodide of tetralnethylanimonium. From these experiments it seems doubtful whether the true Propylamine has yet been obtained. It would also be as well to examine by experiment whether PetirLine is really entitled to the name of Butylamine. This question might be easily decided by the behaviour of petinine with iodide of methyl or iodide of ethyl. * Ann. Ch. Pharm. LXXXUI 116. f-Ibid. LXXLX 29.

ISSN:1743-6893    

DOI:10.1039/QJ8530500229

出版商:RSC    

年代:1853

数据来源: RSC