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PROCEEDINGS OF THE CHEMICAL SOCIETY. No. 106. Session 1891-92. February 4th, 1892. Professor A. Crum Brown, F.R.S., President, in the Chair. Mr. George German was formally admitted a Fellow of the Society. Certificates were read for the first time in favour of Messrs. Meredith Wynter Blyth, 17, Marlborough Hill, N.W. ; Reginald Busby Brown, Ellerslie, Knighton Park Road, Leicester ; Arthur Carey, Gateacre, near Liverpool ; Haridas Garjari, M. A., Agi-a College, Agra, India ; Ercest E. Milnes, Ashfield, Bradford ; Arthur Trobridge, Langley, near Birmingham. Of the followiug papers those marked * were read :-"10.3. " Pedetic motion in relation to colloidal solutions." By William Ramsay, Ph.D., F.R.S. Pedetic motion of small particles depends (1) on the size of the particles; (2) on their demity; (3) on the nature of the medium in which they are suspended.An electrolyte does not cause the motion to cease at once, but the particles cohere when they happen to touch, and ultimately form clots or clusters. If an electrolyte bo not present, the particles do not seem to touch. From observations with the microscope, it is calculated that a particle with a mass of 2.8 x grams moves through approximately its own diameter 1.4 x lW4 cm in a second. Such a particle has one hundred billion times the estimated mass of a water molecule; hence, if its motion be pro-duced by bombardment from water molecules, these must exist in complex groups of considerable mass, and of some stability. It is very unlikely that pedetic motion is the result of electric charges on the particles, because they appear to be uninfluenced by each other’s motions ; there is no obvious source of such electric potential ; and, moreover, we know from Meesrs.Linder and Picton’s experiments the result of electrifying them : they are repelled from the positive or negative pole, according to their nature ; but their pedetic motion is not interfered with, and is qiiite different in kind from the flow from the pole. An explanation of this repulsion has been given by Quincke (1861) and by Clausius (1879). The fact that pedesis is stopped by the addition of an electrolyte would appear to show that the water complices are disintegrated by the presence of ions ; it may be that the individual water molecules are attracted by one or other ion, or by both.The effect of pedetic motion in a liquid is to cause hydrostatic pressure ; such hydrostatic presslire would be less on a membrane capable of penetration by the molecular aggregates or particles ; and as the suspensions examined by Messrs. Linder and Picton and the colloids investigated by Graham will not pass through porous clay, they must exert pressure on its surface ; the water having fairly free ingress and egress, due probably to the disintegration and the re- formation of its molecular complices. From actlual observation of pedetic motion under the microscope, it cannot be doubted that the relative velocity of two particles depends on their mass ; and if their volumes are approximately equal the less dense particle moves much more actively than the more dense.It would appear not in the least unlikely that equal numbers of equally sized particles would exqt equal pressure, as in the case of gases. In an article by Lothar Meyer (Kql. preuss. Akad. d. Wisswch., 1892, 26th November) on Osmotic Pressure, he points out the great discrepancy observed between all measurements of osmotic pressure (except those of Pfeffer on sugar) and the pressure calculated on the supposition that the space was filled with a gas at the same tem-perature ; in all cases the observed osmotic pressure is too low, if it be supposed that ionisation occurs. There are three possibilities : (1) the so-called semi-permeable membrane acts as a sieve, and is quite impermeable to molecules over a certain volume ; (2) the mem- brane is not impermeable, but allows molecules of different momenta to pass at different rates, as with gases of different, densities and porous clay; and (3) there is combination of the dissolved substance with the membrane walls, transference through and dissociation of the compound at the interior surface of the walls, as with hydrogen and a palladium diaphragm.Tammann has shown the great probability of the truth of the last hypothesis. I am disposed to conclude that solution is nothing but subdivision and admixture, owing to attractions between solvent and dissolved 19 substance accompanied by pedetic motion ; that the true osmotic pressure has probably never been measured ; and that a continuous passage can be traced between visible particles in suspension and matter in solution ; that., in the words of the old adage, Nuturu nihil fit per saltum.DISCUSSION. Mr. J. Y. BUCHANAK,having inquired whether muddy water, such as that flowing from the Rhone into the Lake of Geneva, would exhibit a higher density than the clear water when tested by a, hydrometer; and Mr. FRISWELLhaving said that it was well knowii that it was impossible to exactly ascertain the density of oil of vitriol containing lead sulphate in suspension by means of a hydro- meter, Professor RAMSAY said that as particles in pedetic motion exercise pressure, they necessarily tend to force the hydrometer bulb upwards, and thus cause an apparent increase in the density of the liquid.Referring to the stoppage of dissolved substances by partly perme- able membranes, Mr. HOWARDpointed out that the puritication of water by sand filtration bad been traced to the forniation of growths 0x1 the surface of the sand ; when these growths reached a certa.in stage, however, they ceased to act. *104. " The acid action of drawing paper of different makes." ByW. N. Hartley, F.R.S. In a communication to the British Association, " On the fading of water-colours" (cf. Chew. News, 54, 263, 1886), I showed that moisture and acidity were thc chief causes of the fading of certain pigments. The acid in the air of towns is produced from sulphur in the coal, in the air of roonis from the excessive amonnt of gas which is burnt, and in certaiu colonrs according to their mode of prcpamtion.It was suggested that even the slight acidity of draw-ing papers might be expected to facilitate chemical change, the action in each case being a gradual one. I had experimeitted with various kinds of the best paper in nse, both of old and recent manufacture, and had come to the conclusion that such papers were invariably acid, even those of t)he most excellent quality. The fact was accounted for as follows :-The fibre of which the paper is made is steeped in dilute sulphuric acid, and the subsequent washing with pure water does not entirely remove the acid from linen fibre, of which the best papem are made.I have actually found fine linen to retaiu traces of acid after it has been steeped in frequently renewed pure distilled water for a period of three weeks. The acid seems to combine with the fibre, and the resulting compound is only slowly decomposed or dis-solved by the action of water. Such linen gives a blue colour when 20 an aqueous solution of iodine is dropped upon it. There was no inten-tion to convey the idea that the paper contained free acid in sllch quantity that it could be easily removed by washing, or that it would affect Zitmus papeil., which generally is not a sensitive agent,. The samples of paper exhibited at the meetin? were carefully tested in the following manner :-A pure and neutral solution of azolitmin prepared from litmus was allowed to drop upon the paper and soak into the fibres; the edges of the drops were then examined, and found to be red.The bulk of the liquid was then removed by a piece of the same paper, with the result that in every case a red spot was seen, which dried red. Another mode of testing was as follows : -A clear sable brush washed in distilled water was used for applying a wash of pure neatral azolitmin solution, as if it were a pigment; such washes turned red upon the paper. Professor Church, in his valuable work on “ The Chmzistrz/ of Painds and Painfing,” p. 290, published in 1890, remarks that he is unable to endorse my statement that the best drawingpapers hare an acid action. He finds, in fact, that sized papers are generally neutral to test-papers, and that inferior papers are more often slightly alka- line than acid.As some dorxbts may be entertained as to the quality of the papers examined by me, it may be well to state that they were all of the best quality, most of them being of Whatman’s make. That no question may arise on this point, I have tested the samples named below in three ways : first: by dropping litmus solution upon the paper; secondly, by washing with a sable brush; thirdly, b,y steeping strips of paper in pure distilled warm water, and testing the water for acidity, and also €or sulphates. The acid action was recognised by a pure litmus solution, by an ordinary laboratory preparation and by a carefully prepared solution of helianthin, though this last agent is not very sensitive. The results are identical with such as I obtained on former OCCR-sions. The description of the samples and their actions is as fol- lows :-1. Whatman’s hand-made paper, 96 lbs., old make.Washes, acid ; drops, acid ; water, decidedly acid. Large precipitate with barium sulphate insoluble in dilute chlorhydric acid. 2. Whatman’s double t)hick Imperial, 140lbs. Washes, acid ; drops, acid ; water, decidedly acid. Large precipitate of barium sulphate, as with No. 1. 3. Whatman’s double elephant, hand-made. Washes, acid ; drops, acid ; water, strongly acid. Large precipitate of barium sulphate, as with No. 1. 21 4. Whatman’s hand-made, 72 lbs., 1887.Washes, acid ; drops. acid ; water, decidedly acid. Large precipitate of barium sulphate, as with No. 1. 5. Saunders’ hand-made. Washes, acid ; drops, acid ; water, d‘e- cidedly acid. 6. Hollingwort h’s machine-made paper. Washes, barely acid ; drops of stroiig litmus neutral in colour ; water, very slightly acid, almost neutral. 7. Arnold’s unbleached, han d-made paper. Washes, acid. No further test for aAdit-y welie recorded. All these samples were procurcd from Mr. Spence, Lower Sackville Street, Dublin, especially for the purpose of these tests. It will be seen from these notes t<hat there were good grounds for attributing an acid action to even the best of drawing papers. In other words, if a very sensitive solution of pure litmus be applied to paper in the same manner as a strong pigment, as for instance in delicate washes, the action is, in almost every case, distinctly acid ; but if a drop of‘ a strong solution be allowed to sink into the paper and dry up, its colour may be so slightly changed as to appear violet, leading to the infer- ence thst the paper is neutral.The strength of the solution of litmus, and the manner in which it_is applied, must therefore be taken into account, because the quantity of the purple colouring matter in contact with the paper may be more than sufficient to overpower the red tint caused by the acid present in the moistened material. It is therefore extremely probable that there has been no difference be- tween the opinions of Professor Church and myself, but only an incomplete understanding as to the degree of acidity of the paper.Solutions of heliauthin painted on the various samples of paper gave at first a pure yellow tint, which gradually changed to a colour inter- mediate between rose-colour and yellow. Very dilute solutions, washed on freely, showed after some minutes a pale rose-colour, mixed with a yellowish tinge. A sufficiencyof acid yields a fine rose tint with such a solution. Hollingworth’s paper did not show in aziy degree an acid action with helianthin, although it gave a slight indication with litmus. DISCUSSION. Mr. WADEremarked that perhaps the snlphate detected by Professor Hartley was derived from thiosulphate, which, it was well known, was used as an antichlor in manufacturing paper.Mr. GROVESsaid it would be desirable to know more of the history of the papers. Was gas burnt in the roomin which they were stored, and were the sheets examined taken from the tops of the packets ? If so, it was possible t,hat the sulphuric acid was derived from the gas ; 22 it would be desirable to test the centre portions of sheets taken from the middle of the packet. Professor HARTLEY'Sremarks on this criticism are as follows :-The circumstances are not within my recollection, and I am unable to make enquiry at present, but drawing paper in sheets is kept in drawers, at a height of not more than three or four feet from the ground, and carefully protected from dust and damp. As a rule, the samples tested by me have been taken from the middle sheets of sketch blocks prepared from Whatman's hand-made papers, and purchased from Lechertier, Barbe and Go., Regent Street.Imperial and double elephant were the kinds most used. I am well acquainted with t,he effect of a sulphurous atmosphere on paper, bnt cannot think that the acidity to which I refer is to be attributed to such a cause. 105. "The interactions occurring in flames." A correspondence between Sir G. G. Stokes, Bart., F.R.S., and Henry E. Armstrong. The following correspondence will serve as a contribution to the recent discussion of the chemistry of flames brought under the notice of the Society by Professor Smithells and Mr. Ingle, and by Professor Lewes.The paper referred to by Sir G. G. Stokes is entitled "On an optical proof of the existence of suspended matter in flames '' (cf. Proc. Roy. 80c. Edin., 1891). It was reproduced in Nature, 44, 263,1891. " 4,Windsor Terrace, Malahide, Ireland, "23rd September, 1891. ''DEARDR.ARMSTROKG, ';I enclose a little optico-chemical paper, that is tca say, one in which the method is optical, but the results are of interest, such as they have, rather from a chemical point of view. I use, to express it in short terms, a flame as a screen on which to receive an image of\ the sun. " The reaction mentioned in the P.S. is to be taken ap a specimen of reactions of the kind, for though it probably takes place, there are doubtless others also, as there are a lot of compounds found in the interior of the flame."I read the other day your address to the Junior Engineering Society, in which you speak of oxygen as combining with hydrogen in preference to carbon ; I shouId have supposed it would have been the other way. Not only does the facility with which steam is de-composed by glowing carbon favour this view, but it seems to me to fit better with the phenomena of flanics. According to my notions, we must carefully distinguish between the changes which take place in the partial combustion of a molecule and those which are produced 23 in neighbouring molecules as a result of the heat thus produced. We may, for the sake of a name, call the former pure-chemical, and the latt,er thermo-chemical.The action of the heated walls of a tube is of the thermo-chemical kind ; it involves a regrouping of the existing molecules under the molecular agitation o€ a hot body, without briug- ing a fresh reagent (suppose oxygen) into play from outside the molecule. I think that in the blue base of the flame of a candle, where oxygen is plentiful, we have pure-chemical changes. The blue shell invests for a little way the highly luminous shell, like a calyx investing a corolla, and I think the thin shell of glowing carbon, to which the bulk of the light is due, owes its origin to a thermo-chemical change, the heat being derived from the combinatioiis with oxygen which take place just outside it. ‘(I imagine that the hydrocarbon spectrum is due to a gas formed by a pure-chemical as distinguished from a thermo-chemical change.But what gas is it ? It is commonly supposed to be acetylene. To me it seems more probable that it is marsh gas, formed by a pure- chemical, not a thermo-chemical, change. According to my notion, this unknown gas (x,say) is a hydrocarbon, which when burnt without admixhre of other hydrocarbons would show but feebly if at all the hydrocarbon spectrum. More especially might this be expected to take place if it were burnt at a reduced pressure, or considerably diluted with, say, nitrogen. For in order that x should show its spectrum its molecule must be in a state of violent agitation, which it might be expected to be if it had been born as a result of partial combustion, but would not be merely because it was going to be slain by union with oxygen.LLIhave not seen a statement as to the spectrum of marsh gas, as pure as may be, when burnt. Perhaps you know about it. As hydrocarbons in general (I don’t know how it is as to marsh gas) show the same spectrum, a: must be some gas of a simple kind formed in the process of partial combustion, though probably (at least under ordinary circumstances) itself burnt almost immediately afterwards. ‘‘Yours very truly, ‘‘ U.G. STOKES.” “January lath, 1892. “ DEARSIRGEORGESTOKES, “The question of the manner in wliich hydrocarbons are burnt, raised in your letter, has recently (on December 3rd, 1891) been brought under discussion at the Chemical Society by Professor Smithells in two papers dealing with the structure and chemistry of flames ; the conclusions at which he arrives are practically identical with yours.“In making (in 1887) the statements to which you refer, I was, to a certain extent, but reiailing a not uncommon opinion, although probably I was led to give prominence to the idea that hydrogen is the more combustible constituent of a hydrocarbon by the circum- stance that a gas, such as methane, CH4, yields acetylene, C,H,, as one of the products of its incc mplete combustion ; it is possible that this latter may be formed by he agency of heat alone, but I certainly am inciined to regard its production as due to partial removal of the hydrogen from CH, by oxygen, the more so, as Dr.Miller and I mere unable to detect acetylene in oil gas manufactured by passing petroleum h-jdrocarbons through highly heated retorts (cf., C.S. Tram., 1886, 80). Clearly, however, the case is one about which we can only reason at present; a crucial experiment which would afford a solution of the problem will not be easily devised, I think. “At the close of 1886, when my address was written, we were but beginning to realise that the phenomena of combustion are far less simple than had up to that time been taught. Had I spoken of the subject a year or two later, I should undoubtedly have adopted a less dogmatic style. Still, while admitting that the facts do not justify the assertion that oxygen combines with hydrogen in pre-ference to carbon when a hydrocarbon is burnt with insufficient oxygen, I am unprepared at present to accept the alternative view which both you and Professor Smithells advocate, that the carbon is the more combustible ; I think the actual condition of affairs is far less simple than is expressed in the statement of either of these views.“In the case of the changes attending combustion, you would draw il distinction between “ pure chemical ” and “ thermo-chemical ’’ cbhanges. It is impossible to deny that such a differentiation of the changes is seemingly necessary, but perhaps after all the difference is but superficial. ‘‘I cannot help thinking there is very little opportunity in flames for simple heat changes to occur ; the molecules of diferent kinds are so mixed up together.Thus opportunity is given for interactions to occur, the end result of which is the same as that of a simple heat change of the chief siibstance concerned, merely because a change occurring at oue moment is reversed the next, and so escapes notice. In this way contiguous molecules may play the part of surfaces, and that such actions are of primary importance in the case of “decom-positions ” as well as in the case of ‘‘ compositions,” there can, I think, be little doubt, Thus it appears to be established that a pure mixture of carbonic oxide and oxygen is incombustible; is it not therefore reasonable to suppose that under parallel conditions pure carbon dioxide is unresolvable into carbonic oxide and oxygen ? Again, the results of recent experinieiits by Victor Neyer seem to 25 prove that, as I have long suspected, the formation of water from hydrogen and oxygen is not.the simple phenomenon it is represented to be by the simple equation 2H, + 0, =2H20; and conversely it is well known that the extent to which the dissociation of water takes place depends on the character of the surface in contact with which it is heated, and not merely on the temperature. In fine, it seems per- missible to doubt whether under the conditions prevailing in flames carbon is ever separated by simple heat changes ; at all events, there is at present no evidence compelling us to conclude that it is. "Professor Smithells contends that probably carbon has a higher heat of combustion than hydrogen ; this may be, but in the absence of all data from which the heats of combustion of atomic carbon and hydrogen can be inferred, we cannot, with safety, base any argument on thermochemical values.But even if it havc, it; does not follow that carbon is not liberated by partial combustion of hydrocarbons. It is not merely a question of the relative affinities of carbon and hydrogen for oxygen. The carbon wonld not, I imagine, be atomic carbon, but that complex molecular form which occurs in the flame in the solid state, and being incandescent renders it luminous. The genesis of such carbon is expressible by an equation such as Professor Smithells takcs no account of the heat evolved in the formation of C, from xC.I may also point to the superior stability at high temperatures of CO, as compared with CO as remarkahle, seeing that it is the more complex molecule, especially as there is some ground for the belief that proportionally more heat is evolved in the 6xation by carbon of the first than of the second atom of oxygen (cf. Phil. Mug. [5], 23,103, Feb., 1887). The probable explanation, as Bertbelot has suggested, is that in this case, also, the decomposi- tion of GO is promoted by the tendency of carbon atoms to combine. ''It is also to be remembered that, although carbonic oxide as well as carbon and steam appear to interact readily enough if the tempera- ture be sufficiently high, dry carbonic oxide and carbon do not burn in dry oxygen ; nothing better illustrates the difficulty of'drawing con- clusions in these cases than such facts as these."There is another point of view from which the phenomena may be regarded, from whicb it would seem that it is impossible to define either constituent of a hydrocarbon as the nore combustible, except in a purely conventional sense. We may liken the interchanges occurring in an oxygen-methane mixture to those that occur in a cell in which two like electrodes are immersed in two different electro- lytes-an aluminium acid-alkali cell, such as Wohler (?)proposed, for example. The oxygen molecule O2corresponds to the aluminium, the 26 hydrogen and carbon of the methane to the acid and alkali ; and just as the aluminium is attacked in two ways, so the oxygen may con- ceivably become distributed between the carbon aiid hydrogen.The formation of the two aluminium compounds is independent of the relative affinity to aluminium of the radicles of the acid and alkali, and in like manner that of the two oxides from methane would be conditioned by the orientation of the oxygen atoms relatively to the carbon and hydrogen a'toms of the hydrocarbon ; for we may assume, I think, that the colliding oxygen and hydrocarbon molecules con- jugate if only during a very brieP interval of time, and that inter- action is indeed a conseqnence of the opportunity thus given to the atoms to regroup themselves. " There appears to be no doubt that surfaces of various kinds-I would even include gaseous surfaces-play an all-important part in promoting all kinds of recersible changes ; but it is a fair question for discussion whether their action is not also of a " pure chemical " character.The fact that the nature of the surface is of moment is in favour of the view that it is-the surface must be a compatible one : the separation of hydrogen from a hydrogen compound being especially promoted by platinum, which undoubtedly has a strong affinity for hydrogen, and that of oxygen being promoted by silver, which, at high temperatures, is known to absorb this gas. On the other hand, copper, although so readily oxidisable, does iiot appear to promote the decomposition of water. Even in such a case as that of t,he dissocia- tion of carbon dioxide by red-hot porcelain, it is conceivable that the porcelain may exert an attraction over atomic oxygen sufficient to induce its scparation from carbon.I, therefore, am not satisfied that the action of the heated walls of a tube is, as you suggest;, strictly of the thermo-chemical kind. " There is a striking passage in Fnraday's paper on the influence of platinum in promoting the interaction of hydrogen and oxygen (Exp. Xes., Series VI, paragraph 656, November, 1833), which shows that he ha& clearly realised how important is the influence of surface action even in the case of flames. He says :-" 'I have pursued this subject at some length, as one of great con- sequence, because I am convinced that the superficial actions of matter, whether between two bodies, or of one piece of the same body, and the actions of particles not directly or strongly in combination are becoming daily more and more important to our theories of chemical as well as of mechanical philosophy.Tn all ordinary cases of combustion it is evident; that an action of the kind considered, occurring upon the surface of the carbon in the fire, and also in the bright part of a flame, must hare great influence over the combina- tion there taking place.' 27 " Regarding the interactions in flames as consisting in a series of simultaneous and consecutive explosions, of which we can only examine the final steady state, it seems to me that the phenomena are necessarily of an excessively complex character, and that their appreciation and successful interpretation must tax oiir powers of mental analysis in a very high degree. It will certainly be unwise at present to infer that the oxidation of the hydrocarbons, or t,he separation of carbon and also of hydrogen from them, takes place entirely in any one way."Yours very truly, ''HENRYE. ARMSTRONG." "21st January, 1892. "DEAR ARMSTRONG,YEOFESSOR " Perhaps I may be allowed to add a few words in explanation of what I meant by thermo-chemical change. I had not in view thermic measurements. I will endeavour to explain my ideas by an example. Let us contrast (a) the formation of water from mixed oxygen and hydrogen, (b) the formation of acetylene and hydrogen from marsh gas at a high temperature.In both cases alike mole- cular agitation is required to bring about the change; in (a) if the change be brought about at one point, the consequent agitation supplies the requisite disturbance to the neighbouring molecules, and the change is propamgated with explosions; but in (b) I picture to my own mind the change as taking place in this way. When sufficient heat is scpplied to the gas from without, the collisions of the molecules of the marsh gas become sufficiently violent to allow the carbon atoms in a pair to get into a condition in which their tendency to self-combination comes into play, and in the coalescing a portion of the total hydrogen in the pair is thrown off. But the continuance of this change is dependent on a continuous supply of heat from without, under which it is gradually effected.I should call (a) a pure-chemical change, even though heat at one point is necessary to start it, and I should call (b) thermo-chemical, even though chemical affinities are concerned in it. "The results of Professor Smithells seem to me to make it probable that z may be carbonic oxide. '' Yours very truly, " G. G. STOKES." 106. " Properties of alcoholic and other solutions of mercuric and other chlorides." By S. Skinner, M.A. The author has determined the variation in the boiling point of alcohol produced by dissolving in it mercuric, lithium, magnesium 28 and calcium chlorides, as well as the variation in the boiling point of a solution of hydrogen chloride of constant boiling point produced by mercuric chloride.He has also studied the distribution of mercuric chloride between the two solvents water and ether. The results indicate that mercuric chloride affords a case in which the measure of the property is a simple function of the quantity of salt present, whereas in the case of the other chlorides the measure of the property involves some higher power. 107. “ The isomeric a-bromocinnamic acids.” By S. Ruhemann, Ph.D., M.A. An account is given of experiments on the action of ammonia and phenylhydrazine on the ethereal salts of the two isomeric bromo-acids obtained on withdrawal of hydrogen bromide from dibromhydro-cinnamic acid. Whereas tho ethylic salt of a-bromocinnamic acid and ammonia readily interact, yielding a-bromocinnarnonamide, the a.isocinnamate is scarcely affected by ammonia. Both salts are converted by phenylhydrazine into a compound of the formula C,,Hl,N,O, the change taking place less readily in the case of the iso-salt. The author regards this product as cinnamyl- phenylazimide ; the same substance is more readily prepared by inter- action of ethylic dibromhydrocinnamate and phenylhydrazine. In both cases t,he yield of azimide is but small, the main product being a compound of the formula C2,H18N,0,,probably the irnide of di-cinnamylphenylazimide. The author discusses the manner in which this compound is formed. ANNIVERSARY MEETING AND SECOND ANNIVERSARY DINNER. The Anniversary Meeting will be held at Pour o’clock in the After-noon of Wednesday, March 30th next. It is arranged that QII the evening of the same day the Fellows and their friends will dine together at the Whitehall Rooms, Hatel MBtropole. At the next meeting, on February 18th, there will be a balIot for the election of Fellows, and the following papers will be read :-“ A search for a cellulose-dissolving (cytohydrolytic) enzyme in the digestive tract of certain grain-feeding animals.” By H. T. Brown, B.1t.S. “ Some experiments on alcoholic fermentation.” By A. J. Brown. Limettin.” By Professor Tilden, F.R.S.‘6 EAPPISON AND SONS, PUINTEHB Ih’ ORDINAXY TO HhX NAJES‘l‘X, ST. MABTIN’S LANE.

ISSN:0369-8718    

DOI:10.1039/PL8920800017

出版商:RSC    

年代:1892

数据来源: RSC