CHEMICAL SOCIETY OF LONDON. IIoiise of the Society of Arts John Street Adelphi. 23rd February 1847. A MEETING was convened to take into coasideraticn the formation of a Chemical Society at which meeting a Provisional Committee was appointed for carrying that object into tXiJct. The Provisional Comniittee having issued a printed circular in- viting a number of gentlemen engaged in the practice and pursuit of Chemistry to become original members the following gentlemen communicated their written assent :-Aikin Arthur. Andrews Dr. Thos. Barron Rev. J. A. Blake Jas. Blythe Win. Brande Prof. W. T. Brayleg E. W. Jun# Brooke €1. J. Button Chas. Clark Dr. Thos. Cock W. J. Cooper J. T. Cooper J. T. Juu. Crossc A 11dre \v. Crurn Walter.Cumming Prof. J. Danieil Prof. J. F. Daubeny Dr. C. Davy Dr. E. De la Rue IF7. Everitt Thos. Ferguson Wm. Fownes G. Frampton Dr. A. Gassiot J. P. Gill Thos. C'hein. Proc.-?rJo. Graham Prof. Thos Graham John. Griffin J. J. Grifitlis Thos. Grove IV. R. Heisch C. Hennell 1%. Henry T. €1. Herapath Wni. Hope Dr. T. C. Hughes F. R. John son Pe r c i vd &4. Johnstou Prof. Jas. Leeson Dr. W. 13. I,ongstal€>Dr. G. D. Lowe Geo. MGregor Dr. Rob. 3I:tcintosh C11as. Mi.rcer J ,b n . >Iiller Prof. W. H. Illoody Col. Thos. Musliet David. Paris Dr. J. A. Pattinson 13. I,. Pearsall Thos. L. Penny Prof. F. Pepjs JV. H Phillips Riclisrd. Play fair Dr. LYOU. POIrett Robert.Potts Dr. I,. H. ]lees Dr. G. 0. Ileitl Dr. D. 130swcll. Richardson Thos. Scanlan Maurice. Sinks Wive. Smith Denham. Solly E. Jun. Stenhuuse Dr. J. 'raylor Richard. Tcnnant John. Teschcmacher E. F. Thoiiiso~i,Dr. Thos. ?'honi>on Dr. It. 1). Turner Dr. Wilton. IVaringtan Rob. West Win. CVheeler~Jas. Lowe. Wilsoii John. Wilson Dr. G. Yorkc Col. P. ASocicty of Arts LTliwc?t %MA 18 1.1. The miiiutes of the previous meeting having been read and colt- firnicd the report of’ the Provisional Coiiiniittee was brought up and adopted with ainentlnients for the prosetit government of the Socicty. The following gentlemen were tlieii elected as Officers and Council for the ensuiiig year :-~-’1.csi~leiLr.-Prof’cssorT.Graham. I.’ice-Presine/!ts.-I’rofessor W. T. Brande ; J. T. Cooper Esq. ; IhfesSor J. F. Daniel1 ; Rich. Pliillips Esq. Trects rc rer.-Ar t ti ur Aikin Esq. Secretciries.-E. F. Tcscheinacher ; Robert Warington. Cocu~cil.-Dr. T. Clark ; Professor J. Cummine; ; Dr. C. Dau-beny ; Thonias Evwitt Esq. ; T. Griffiths Esq. ; W. R. Grove Esq. ; H. Hennell Esq. ; G. Lowe Esy. ; Professor W H. Miller ; W H. l’epys Esq.; Rob. Yorrctt Esq.; Dr. G. 0. Ilees. April 13.-The President in the Chair. The following are abstracts of the papers which were read :-1. “On the Preparation and Formation of Yellow Yrussiate of Potash,” by Professor Liebig. In order to explain tlie reaction between animal matters and carbon- ate of potash when fused together at a red heat which gives rise to this salt it is necessary to keep in mind the following properties of the salt When heated to redness in a close vessel ferrocyanide of potnssiunl is deconiposed into cyanide of potassium carburet of irou and iiitro- fen gas; that is looking upon the ferrocyanide of potassiuiri as a double cyanide the cyanide of iron is converted into carburet of iron and nitrogen gas while the cyanide of potassium escapes de-composition.The cyanides of metals in general which can conibine with carbon are decomposed in the same way as the cyanide of iron ; thus the cyanide of silver when heated gives at first a little cyano- gen but afterwards it fuses and glowing suddeiily gives nitrogeii gas the carbon remaining in combination with the silver.The addition of carbonate of potash to the heated f’errocyanide of potas- sium prevents the decomposition of any cyanogen cyanide of potas-sium being then formed together with oxide of iron; and when charcoal forms a third ingredient of the fused mixture the oxide of iron is reduced to the rnetallic state. Hence ferrocyanide of potw- sium cannot be supposed ready formed in the red-hot mixture of the iron pot in which it is manufactured that mixture containing both charcoal and carbonate of potash. A general view is then taken of the proccss of manufacture of this salt. Animal substances such as dried blood horn hoofs and bristles with common pearlashes arc) tlie materials employed. The aniinal niattcr is used either in its natural state or it is previously submitted to distillation as in the pwpnration of anitnoilia and the 3 residual charcoal merely employed for the manufacture of the prus- siate.The projection of animal matter into the melted potash oc- casions a lively effervescence from the evolution of carbonic acid and some combustible gases. The liquid is stirred after each addi- tion of the materials. The usual proportions eniployed are equal parts of pearlashes and aninial matter or ten parts of the former and eight parts of carbonized animal matter. Three or four per cent. of iron filings are usually added to the mixture. After each addition of animal matter the heat is urged until the whole is fused and the melted material which is of a thick consistence is iiot re- moved from the pot until the charcoal is sew to be equally diffused through the whole mass.The mass after cooling is placed in ail iron pan filled with water the clear liquid after a time drawn 0% and water boiled several times on the insoluble residue. The liquids are evaporated for crystallizing the salt at a temperature not exceed- ing 203' Fahr. The formation of prussiate takes place after the solution of the melted mass by the action of the matters dissolved upon the insoluble residue ; for this melted mass yields nothing but cyanide of potassium to alcohol and contains no prussiate. In ex- planation of the formation of. cyanide of potassium in the melted mass it is stated that metallic potassium readily produces that salt when fused with calcined blood disengaging at the same time a considerable quantity of' charcoal ; the proportion of nitrogen to carbon in cyanogen being one equivalent of the first to two of the last while in bhod hair and horn the proportion is 1 to 6.Kow when these animal matters are fused at a high temperature with potash the free charcoal reduces the potash tb the state. of potas-sium ; the latter then acts upon the azotized carbonaceous matter forming cyanogen with which it unites. A second mode in which cyanide of potassium is produced is when ammoniacal gas is con- ducted over a mixture of carbonate of potash and charcoal at a red heat. This is accounted for by the action of ammonia upon cliar- coal alone at a red heat ; the gas is entirelF converted into hydro- cyanic acid and hydrogen (N H and 2 C =H N C and 2 H).Now hydrocyanic acid decomposes carbonate of potash at a red heat forming cyanide of potassium. Hence the product of cyanide of potassium is most considerable when the aninial matter is used in its natural state and not previously carbonized a fact of which the manufacturers of prussiate of potash have long been aware from experience. To account for the subsequent conversion of the cyanide of potassium in the process into prussiate it is absolutely necessary that iron exist in the fused mass ; but it may indifferently be in the condition of metallic iron the protosulphuret or the protoxide of iron. The first is readily dissolved by a solution of cyanide of potassium with evolution of hydrogen gas (3 K Cy with H 0 and Fe =2 K Cy Fe Cy and K 0 and H); the second with the formation of sulpliuret of potassium and the third with that of caustic potash.When the iron is added in the state of protosul-phate to a solution of cyanide of potassium one third of the latter salt becomes cyanide of iron (a browii insoluble matter) which is dissolvcd by the other two-thirds of the alkaline cyanide and the ferrocyanide formed. These processes are not altered in the slightest degree by mixing caustic potash or its carbonate or the sulpliuret of potassium with the solution of cyanide of potassium. Much of the iron necessary it is well kiiomn is derived from the corrosion of the iron pot in which the fusion is conducted.Professor Liebig assigns an importaut place to the sulphur of the siilphate of potash usually present to the extent of 12 or 16 per cent. in pesrlashes in effecting this corrosion. In the decomposition of the sulphate of potash by charcoal bisulphuret of potassiiun is formed and carbon- ate of potash. Thus 2 SO,-t2 K 0aiid 4CtKS and KO C 0 with2 C 0,and C 0. The bisulphuret of iron assumes an atom of iron either from the sides of the iron vessel or from iron filings which are added ; the double sulphuret thus formed is very fusible and will corisequently be equally diffused through the mclted mass. The deficiency of product which frequently occurs in the manu- facture of prussiate of potash is ascribed principally to two causes lst to the want of iron in the fused niass.The cyanide of potas- sium is then instead of being converted into ferrocyanide when thrown into water,'dtcotnposed by thc free caustic potash when heat is applied to its solution. Uniting with the elements of water its cyanogen is converted into formic acid and ammonia NC K and 4H 0 =C2H0 + KO and NH,. This destruction of thc cyanide may be avoided by adding iron or its sulphuret to the ley or better the protosulphate of iron. Another cause of loss of cyauitle in the pot itself is poirited out. The bisul- phuret of potassium yields sulphur to the cyanide of potasium and coiiverts the latter into sulphocyanide of potassiuni. But if the irrixture contain a quant.ity of iron suficient to unite with all the sulphur the forination of sulphocyanide will be prevented.Indeed sulphocyanide of potassium itself is decomposed by iron at a high teniperature and resolved into sulphuret of iron and cyanide oP potassium. It is thus seen that by increasirig the proportion of iron the formation of sulphocyanipe is at once prevented and sulphuret of iron offered in quantity more than suficient for its solution after- wards by the cyanide of potassium. The quantity of iron necessary to add in the tusion varies from 22 to 20 per cent. with the pro-poitioil of sulphate of potash in the potashes used. If a sulpho-cyauide appears in the mother liquors the proportion of iron must bc increased. The only remaining condition for the forination of ferrocyaiiide of potassiuni is the coiiiplete exclusion of air during the fusion.Cyanide of potassium cannot be kept in fusion exposed to air without absorbing oxygen arid being converted into cyanate of potash ; hence the advantage which English manufacturers de- rive from cffecting this fusion in close vessels. Cyanate of potash may also be produced by the action of' cyanide of' potassium upon the sulphate of potash existing in thc potashes sulphuret of potas- sium being at the same time f'onned. Now cyanate of potash is 5 decomposed by the application of heat to its solution iiito carbonate of potash and ammonia. The ammonia which escapes during the evaporation of the ley may therefore come from this source as well as from the decomposition of cyanide of potassium by potash already adverted to.2. “On the Formation of Mellon,” by Mr. E. A. Parnell of Uiii-versity College. This paper referred to the decomposition which occurs in the process for niellon from the substance considered by Liebig to be the isolated radical of the sulphocyanides (as obtained by the action of chlorine or nitric acid on sulphocyanide of potassium) ; for which substance having previously shown it to contain hy- drogen and oxygen in addition to the elements belonging to the true sulphocya~iogen the author proposes the term nwtasulpliocyano-gen. It became necessary therefore to seek for other products of the decomposition of this substance than those hitherto recognized narnely niellon sulphur and bisulphuret of carbon ; and in decom- posing pure and dry metasulphocyanogen by heat water sulphu- retted hydrogen and hydrosulphocyanic acid in addition to the above were detected.Admitting the formula for metasulphocya- nogen S, Cy H 0 to which he has been led by analyses the de- coniposition is explained as follows :-Three equivalents of meta- sulphocyanogen containing S36C, N, H 0, are resolved into four of niellon C, N, ;two of hydrosulphocyanic acid S C N2H ; four of sulphuretted hydrogen S H ; eight of bisulphuret of car-bon s,,C ; twelve of sulphur and three of water H 0,. The sum of the elements of these compounds will be found to comprise S, Cs6 N, H 0 ; or three equivalents of rnetasulphocyanogen. April 27.-Thc President in the Chair. A donation of five guineas from Dr.W. B. Leeson was presented to the collections of the Society. The following communications were read :-3. An extract from a letter from Mr. M. Scanlan of W’olver- hampton describing the appearance of flashes of light observed during the crystallization of nitrate of strontian in the dark. 4. “On some of the Products of the Action of Nitric Acid on Castor Oil,” by Thos. George Tilley Esq. (See Memoirs Vol. I. Art. 1.) 5. ‘(On Bleaching Salts,” by M. Detmer Esq. (See Memoirs Vol. I. Art. 2.) 6. The following Note ‘“Onthe Preparation of Chlorate of Potash,” by Professor Graham. It is well known that the ordiiiary pro- cesses for this important salt are attended with some practical diffi- culties. When a stream of chlorine gas is passed through a strong solution of carbonate of otash the absorption of the gas is rapid and complete till one-half of the alkaline carbonate is decomposed ; 6 but the remaining portion which is in the state of bicarbonate is not so easily acted upon.To decompose the latter salt completely chlorine must be applied in excess and the decomposition is attended by the formation of free hypochlorous acid as has beer] proved by Mr. Detmer. The lipid is also at the end highly bleaching and contains much hypochlorite of potash. The boiling necessary to convert the latter into chlorate of potash and chloride of potassiuin occasions according to M. Morin a considerable loss of oxygen and thus lessens the product of chlorate. When a strong solution of caustic potash is substituted in this process for the Carbonate the absorption of chlorine proceeds witliout interruption ; but the liquid when saturated bleaches strongly from hypochlorite formed.A long-continued boiling is required to destroy this property com-pletely and as oxygen escapes the chlorate obtained iiiust be de-ficient in quantity in a corresponding proportion. The process which the author recommends and which is attended with none of these inconveniences consists in mixing carbonate of potash inti- mately with an equivalent quantity of dry hydrate of lime and ex-posing the mixture to chlorine gas. This mixture although quite dry absorbs the gas with prodigious energy the temperature rises much above 212O and water is freely evolved. When saturated it may be moderately heated which destroys a mere trace of hypo-chlorite it contains.The whole lime is found in the state of car-bonate and the potash as chlorate and chloride of potassium. The solution of the two latter salts is neutral without any bleaching property and free from lime. The chlorate of potash may be crystallized from it in the usual way. Carbonate of potash when moistened and exposed to chlorine witbout the hydrate of lime ab- sorbs the gas with great avidity and certainly answers better than a strong solution of the same salt; but the absorption becomes slow after the salt is in the state of bicarbonate and subsequently a large quantity of the bleaching hypochlorite of potash is produced. In the new process described above there is no reason to believe that the carbonate of pctash is decomposed by the dry hydrate of lime till the chlorine is presented to the mixture; then while the lime attracts the carbonic acid the chlorine acts simultaneously upon the potash and the carbonate of potash is thus readily decom- posed.The same principle of calling in a secondary agency to promote combination may be taken advantage of in many other cases. One of these of some interest is the promotion of the ab- sorption of sulphuretted hydrogen by hydrate of lime through the influence of other salts. Thus hydrate of lime dry or slightly damped ceases to absorb sulphuretted hydrogen long before it is saturated with that gas ;but if mixed with an equivalent of hydrated sulphate of soda the absorption takes place with grcatty increased avidity and goes on till two equivalents of sulphuretted hydrogen are taken up for one equivalent of lime.But here with the assist- ance of sulphuretted hydrogen the hydrate of lime decomposes the sulphate of soda sulphate of lime being formed while caustic soda combines with the sulphuretted hydrogen. 7 The author has found that the last mixture may be applied with advantage from its great absorbing power in purifying coal-gas where the highest degree of purification is desirable and where the products sulphate of lime and hydrosulphuret of sulphuret of sodium caan be economically applied. He recommends it to be introduced into the last of the dry lime-purifiers. 7. An extract from a letter fromOlliveSims Esq.Shelton Stafford- shire Potteries was read announcing a considerable and very access- ible source of the hitherto very rare mineral phosphate of yttria. The crushed cobalt ore from Johanmsberg in Sweden when con- verted into ziiffrc or dissolved by acids leaves a yellowisli iiiineral ill crystalline grailis iii the proportion of about one potind avoirdu-pois from one thousand pounds of ore. This iiiineral is the phos- phate of yttria. It may be decomposed by fusion with alkaline car- bonates or by boiling with pretty strong sulphuric acid. May 1 1.-The President in the Chair. Lectures on Agriculture by C. Daubeny M.D. was presented by the author. The following gentlemen were elected members of the Society -J. AM.Heath Dr.H. B. Jones and F. Watkins. The following is an abstract of a paper which was read :-8. ‘‘ On a Simple and Cheap Method of preparing Hydrochloric Acid absolutely pure and of any required strength,” by Wm. Gregory M.D. Professor &c. King’s College Aberdeen. Much difficulty is experienced in procuring pure and concentrated hydrochloric acid for chemical purposes the common commercial acid containing various impurities particularly sulphuric and sulphu- rous acids free chlorine chloride of iron and sulphate of soda ; these arise from impurities contained in the materials employed ; the chlcrine from the action of nitric or nitrous acid (often present in oil of vitriol) on the hydrochloric acid; sulphurous acid from or- ganic particles in the common salt employed ; and chloride of iron from the presence of that metal also in the salt.Pure and clean materials are therefore the first requisite for a pure acid. Dr. Gre-gory finds that if to one equivalent of salt two equivalents of sulphu- ric acid diluted with a certain quantity of water be used instead of one equivalent as usually prescribed the whole of the hydrochloric acid may be expelled without a trace of sulphuric acid passing ol-er even into the first condensing bottle and that two-thirds of the hydro- chloric acid distil over before water is volatilized ; on this observation the following process is founded. Into a common Florence flcwk are introduced 4oances of the pu- rest patent salt and 5 fluid ounces of sulphuric acid of specific gra- vity 1.600 ; c?.gentle heat is applied and the gas which is then gene- rated is conducted by a bent glass tube iiito a four-ounce phial con- taining 2 ounces of distilled water surrounded with snow or ice-cold 8 water. No safety tube is required as the tube is made to dip only about one-eighth of an inch into the water SO that should any absorption take place the rise of a little water in the tube exposes the extremity of it so as to admit the air ; or for greater security a small bulb may be blown on the descenJing limb of the tube. The gas is absorbed as fast as it comes over and for the first hour and one quarter the heat hardly requires to be increased ; if the tem- yerature of the surrounding water has been kept so low as 50° the 2 ounces of distilled water will have increased in volume to 3 ounces of colourless hydrochloric acid fuming strongly and having a spe- cific gravity of 1-20to 1-21 the gas passing over so dry that no part of the tube becomes warm.This portion being removed its place is supplied by 2 ounces more of distilled water atid the heat gradually increased and continued for an hour longcr; by that time all the hydro- chloric acid is expelled with some water and the 2 ounces of water have become 3 ounces of hydrochloric acid of specific gravity 1.10. Both portions are absolutely pure. If 3 ounces of water are used in the first instance 4.5 fluid ounces of acid of specific gravity 1* 165 are obtained ; and then replacing the acid by 2 ounces of water 3.5 ounces more of specific gravity 1.065.If 5 ounces of water are used at once for condensing the acid and kept till the distillation is com-plete 7.5 fluid ounces of specific gravity 1.155 are obtained. Dr. Clark finds sulphuric acid of a specific gravity of 1-65 to answer still better than acid of 1.60. 9. Dr. Clark then exhibited to the Society his method of ascer-taining quantitatively the comparative hardness of water by means of the common test of tincture of soap illustrated by experimental evidence to prove the accuracy of which it was susceptible and the facility of its application. Dr. Clark hoped at a future meeting to lay before the Society more matiire details of the method exhibited. May 18.-Thc President in the Chair. Thc following were elected menibers of the Societv :A.Y.Chabot Dr. J. H. Gilbert Dr. Wm. Gregory George Shith Pro- fessor J. J. Sylvester John Ward Win. Wegg ; and R Murray E. A. Yarnell J. H. Pepper Associates. 10. A4n extract of a letter from Mr. Maugham was read ''On the Mode of treating Copper Ores and the Ores of other Metals com- bined with Sulphur so as to ascertain the quantity of Sulphur in such Ores and also the quantity of Copper in the native Sulphuret." A quantity of the powdered ore sulphuret of copper about 50 or 100 grains is placed in a porcelain tube tmversing a small furnace and made red-hot ; after remaining for3 or 6 minutes a portion of the sulphur will be expelled ; tl stream of oxygen gas is then passed over it the remaining sulphur is then rapidly given off as sulphurous and sulphuric acids and the copper thoroughly oxidized.By heating the 9 ore when first introduced into the tube it becomes slightly adherent which prevents any of it from being blown away by the oxygen gas. The contents of the tube are then removed into an assay crucible with the addition of black flax and a little charcoal ; the whole co-vered with dry carbonate of soda or borax and submitted to a yeHow heat when a button of copper is obtained. Mr. Maugham finds that arsenic and other volatile met.& that may happen to be present are oxidated and expelled by the heat; but should tin be present it will be found with the reduced copper and must be removed in the usual way. The process is known to be complete when no more vapours are seen to issue from the tube or when the odour of sulphu- rous acid is no longer perceptible.It is however to be observed that white vapours will be seen even after the process is cornplete owing to a portion of sulphuric acid condensed in the tube returning to the hot part. An assay of this kind takes about twenty minutes to execute. When the wet analysis is desirable we have only to proceed as before in the tube part of the process and to dissolve the residue in the proper acids. Mr. Maugham speaks favourably of the use of chlorate of potash added to hydrochloric acid for dissolving certain ores where nitro- muriatic acid is generally employed and afterwards expelling the ex- cess of chlorine by heat ; the known inconveniences of nitric acid in certain cases are thus avoided.The quantity of sulphur contained in the ore is ascertained by elongating the tube traversing the furnace so that it may dip into a vessel containing water saturated with chlorine by wliicli meiiiis the sulphurous acid is converted into sulphuric acid and the quantity of sulphur found from the precipitate with chloride of barium 11. A paper was read ‘‘ On the Atomic Weight of Carbon,” by Professors Redtenbacher of Prague and Liebig of‘ Giesscn. (See Memoirs Vol. I. Art. 3.) June 1.-Thc Presidtwt iii the Chair. Professor J. Liebig was elected a Foreign Member of tlic Society. Dr. B. Babingtan M. Detnier George Hallet H. Inglis, T. W. Reid Jas. Tennent T. G. Tiiley John Wilson werc clectetl Members and Win.Francis Associate. The following coniinunications were then read :-12. Extract of a letter from Col. Yorke “ On a Specimen or Arti-ficial Arragon ite.” ‘‘This substance was taken from the interior of a copper boiler which was used to supply hot water for household purposes ;it Port Eliot Lord St. Germaine’s seat in Coriin.al1. ‘l’hc substance is about hths of an inch thick and by its non-conducting power it caused as I understood the destruction of the boiler. On the surface which was next to the copper it is coated by dioxide of copper. and the Chern. PTOC.-NO. 1. 10 mass appears made up of an aggregation of prismatic crystals whose axes are perpendicular to the surface on which the incrustation formed under a microscope these crystals appear to be six-sided prisms.I compared under a .polarizing microscope portions of the powder of Iceland spar and of arragonite from Bilin with the pow- der of the specimen ; the latter agreed very closely in appearance with that of arragonite. "Among the powder of the specimen were seen some very acute double six-sided pyramids; these with little doubt are similar to those formed by G. Rose by evaporating solutions of carbonate of lime at a boiling heat and described by him as resembling some snpphirc crystals. " On chemical examination it was evident that the specimen con- sisted chiefly of carbonate of lime ; water howevcr dissolved from it a small quantity of sulphate of lime. "The following is the result of an analysis made on 10 grains but which does not pretend to minute accuracy :-Matter insoluble in muriatic acid silica with } oxides of iron and copper.1.3 Sulphate of lime ........................ 1.8 Carbonate of lime.. ...................... 93.3 Carbonate of magnesia.. .................. 3.2 100 "Deprived of its coating of dioxide of copper three trials were made of the specific gravity of its powder ; the sulphate of lime being previously washed off with hot water. "The two first trials were made by weighing about 80 grains of the powder in a small spherical-stoppered phial (whose contents in di- stilled water at 62' was previously determined) and then when filled up with water the third trial was made in the manner described by Rose.The specific gravity being thus determined the powder was in each case dried and slightly ignited (by which operation arrago- nite as is known is converted into calcareous spar) and the specific gravity again taken. The results were as follows :-Spec. Grav. Spec. Gray. Ixfore ignition. after igmtion. 1st trial ...... 2.842 2.708 2nd .......... 2-828 2.701 3rd.. ........ 2.878 2.6S1< --_ Mean.. ........2*849 2 696 The specific gravity of arragonite crystals from Bilin is 2.946. "The highest specific gravity which Rose obtained of arragonite famed by evaporating solutions of carbonate of lime he states was =2.836'. ''Specific gravity of €celand spar is 2-72. I should suppose then that there can be little doubt but that the specimen affords an examplc * The loss by ignition on 43.8 grains was =.08 grains.of the formation of arragonite and a verification of G. Rose’s expe- riments. ‘‘ I have since made two attempts at producing arragonite by Rose’s method of precipitation but cannot boast of my success. The fol- lowing is a note of the best experiment. A solution of 300 grains of chloride of calcium in 4 ounces of water at 212’ was mixed ra- pidly with a solution of 330 grains of carbonate of ammonia in 8 ounces of water at 180’. The mixed liquor was not alkaline. ‘‘The precipitate under the microscope consisted chiefly of radiating epicular crystals extremely minute with occasional rhombohedrons. The precipitate being washed the specific gravity taken before dry- ing came out = 2.751 after drying it was below 2.7.During the washing a slight crackling noise was heard and I cannot help think- ing the precipitate may have been thrown down as arragonite but changed into calc-spar during the washing and drying.” 13. Professor Kuhlman of Lille presented specimens of Chalk hardened by his process for the Silicification of Limestones which consists of immersing them in a solution of silicate of potash ex- posing to air for several days and afterwards washing. Although the chalk did not contain more than three or four per cent. of silica it was capable of scratching many cementa and marbles. In a similar manner he could harden carbonate of lead and plaster.of Paris. He finds alkaline salts in all the limestones containing silica which are hydraulic and believes that they originally resembled ordinary chalk in purity but have been partially silicified by infil- tration of water containing an alkaline silicate in eolution or by a natural process analogous to his artificial one.14. Extract of a letter from Dr. R. F. Marchand of Berlin ‘‘ On the Atomic Weight of Carbon.” ‘‘ I take this opportunity of communicating the results of experi- ments relative to the atomic weight of carlion which Professor Erd- man and myself have very lately obtained. The difference between the numbers recently given by Dumas and that of Berzelius was a sufficient inducement for us to examine and repeat Dumas’s experi- ments much occupied as we are with organic analysis.The burn- ing of diamonds in oxygen gas was easily effected by us in a porce- lain tube by a pretty high temperature. The apparatus employed was very similar to that described by Dumas. ‘I The following are the results :-No. 1. 0.8062 gramme diamonds left a residue weighing 0.0010 gmmme and gave 2.9467 gr. carbonic acid consequently giving the atomic weight for carbon 75-19. No 2. 1.0867 gr. left a residue weighing 0*0009 gr. and gave 3.9875 gr. carbonic acid = carbon 74.84. No. 3. 1.3575 gr. left a residue weighing 0.0018 gr. and gave 4.9659 gr. carbonic acid = carbon 75.10. No. 4. 1.6330 gr. left a residue weighing 0.0025 and gave 5.97945 = carbon 74-98 No. 5. 0.7510 gr. left a residue weighing 0.0010 and gave 2-7490 = carbon 75.03.“ Graphite gave the same numbers ; the residues were pure white silex without a trace of oxide of iron :-No. 1. 1.4580 pmme native graphite left a residue weighing 0.0075 and gave 5*31575 gr. = carbon 75.05 atomic weight. No. 2. 1.5746 gr. graphite left a residue weighing 0.037 and gave 5.6377 gr. = carbon 75.02. No. 3. 1.6578 gr. residue 0*0084 and gave 6.0385 = carbon 75.1 8. No. 4. 1.9040 gr. artificial graphite residue 0.0105 gr. gave 6,9355 gr. =carbon 75-10. “ The mean of these experiments give 75.07 ;we therefore consider 75 as the true number indicated by thesc experiments for the atomic weight of carbon. It is remarkzhle that this number was fixed upon theoretically by the English chemists and Iias now been confirmed by experiments.If we take the number 6.1239 for hydrogen with a very small increase viz. as G.250 we arrive at the numbers for oxy-gen carbon and hydrogen viz. 16 12 2 or 8 6 1.” 15. A paper was rcad “ On Malic Acid and the Salts of Rlalic Acid,” by R. Hagen. (See Memoirs Vol. I. Act. 4.) 16. A paper was read On Yyroxylic Spirit,” by Andrew Ure ‘I M.D. (See Memoirs Vol. I. Art. 5.) The Society then adjourned till Tueiday the second of November next. 13 November 2 1841.-The President Professor Graham in the Chair. Mr. Wm. Hasledine Pepys presented to the Society Specimens of the Nut of Phytelaphas decandra or vegetable ivory in the natural and wrought states. Mr. R. Taylor presented his Calendar of the Meetings of Scientific Bodies of London for the Years 1841 and 1842.Mr. Griffin presented his piiblished List of Chemical Apparatus &c. The following gentlemen were elected members of the Society :-James Beaumont Neilson John Sylvester Angus Croll Wm. Pot- ter Thomas Hawkesleg and Thomas De la Rue Esquires. The following communications were read :-17. An extract of a letter hrn M. Dumas '< On the Analysis of Atmospheric Air." The method of analysis adopted in these experiments was to cause the air under examination to pass through the combustion tube employed in organic analysis charged with reduced metallic copper into an exhausted flask and then weighing the resulting oxide of copper and the nitrogen in the A;&. M. Dumas says ''You may be assured that no combination of nitrogen with copper is formed in the circumstances under which we operate a decided red heat being used ;besides all our analyses agree as you will be able to judge by the following numbers :-By weight."April 27th 1841 2292 oxygen in 10,000 of atmospheric air. .... 2s .... 2309 ........ .... 29 .... 2304 ........ May 29 July 20 .... 22 .... 2301 .... 2503 .... 2300 ........ ........ ........ during heavy rain. during rain,at 1 P.M. 12 P M. clear. .... 24 .... 2305 ........ 12 A.M. cloudy. 'r Thus the three first figures expressing the proportion of oxygen contained in the air are constant the fourth figure variable. I do not consider however that the whole of this difference can arise from errors of observatioii; it is a subject requiring still further examination.MM. hlelloni. and Piria are performing the same experiments at Naples by the same means ;and also M.Stas at Brussels. M. Levy who has assisted in the above experiments in- tends to repeat them in Denmark." M. Dumas urger the repetition of these experiments to be made at various times and in various places a11 over the world to whicli the English chemist has more easy access than others in order to resolve this curious physical problem. "The density of nitrogen nppenrs to me," he adds ''to be be- tween 0.970 and 0-973. That of oxygen with which we have been particularly occupied and upon wiiich we have made twenty dif-ferent experiments is always found comprised between 1-105 and 1.108 ;it appears to be reprcseiited very nearly by 1.106'.That of Chem. Proc.-No. 11. B 14 carbonic acid has varied between 1.526 and 1.528 ; if 75 is adopted for the atom of carbon then oxygen is condensed some thousandths in forming carbonic acid. “ The density of hydrogen is always found above 0.0691 it has varied between 0.0692 and 0.0696 ; we have operated on quanti- ties of about 17 litres of this gas. As to the composition of water by weight which has occupied me personally during nearly two months and on which I am still experimenting I remain doubtful. I have never found less than 12.50 for the equivalent of hydrogen and often 12.55 and at present I cannot choose between them. In adopting the first of these numbers no error of any practical conse-quence can result but as a philosophical question I take so hi@ an interest in it that I shall continue my experiments until they lave no doubt on the subject.” 18.“ On the Analysis of Cetine and Ethal,” by Dr. John Sten-house. (See Memoirs Vol. I. Art. 7.) 19. “ Notice on the Artificial Magnetic Oxide of Iron,” by Tho-mas Starkey Thornson Esq. After adverting to the procese given in the last edition of Tur-ner’s Elements of Chemistry for the preparation of the artificial magnetic oxide of iron the discovery of which is attributed to Abich and Gregory Mr. Thornson says ‘‘ Recollecting that this oxide had been produced some years ago by a process surprisingly similar to that of Dr. Gregory I corresponded with the inventor of it Mr. John Mercer one of the original members of this Society and part- ner in the firm of Fort Brothers and Co.calico-printers from whose letters I extract the following remarks :-‘ This. substance was pre-pared by me in 183 1 and in 1833 applied extensively as a medicine with great success. Mr. Gossage of the Stoke Prior Alkali Works who was staying with me at that time for a few days was so im-pressed with its value as a medicine that upon his return home he wrote to me for a quantity of it to send to his friend Dr. Jephson of Leamington to whom I forwarded a quantity with the receipt for its preparation and the dose. lhis receipt was published by Dr. Jephson and given away among his friends; Dinneford was also employed to make it and also an agent for the sale of it in Man-Chester.’ ” The following is Mr.Mercer’s mode of preparing this oxide -“ Take a quantity say one pound of the common crystallized pro- tosulphate of iron dissolve it in water and add nitric acid in sufficient quantity to peroxidize it and afterwards expel carefully all excess of nitric or nitrous acid by boiling. Tothis add one pound of protosul- phate of iron with water sufficient for its solution. Pour the mixture iuto a solution of caustic potash sufficient in quantity and strength to decompose the whole and then boil. The precipitate thus thrown down consists of a mechanical mixture of the protoxide and peroxide of iron atom to atom ; raise the temperature of the mixture to 212O Fahrenheit and their chemical union is effected.That such is the succession of changes is proved by dipping into the mixture pre- 15 vious to boiling it a piece of clean cotton cloth which after ex- posure to the air for a few minutes and washing in water exhibits the buff stain peculiar to peroxide of iron precipitated upon cotton fibre. But if this is performed after the boiling a dirty black stain is obtained indicating the formation of the black oxide.” This fact is further proved by the oxide after boiling having a crystalline structure when examined under the microscope the minute plates having a brown colour and being transparent although the edges of the crystals are not sufficiently defined to trace the form. Mr. Thomson adverts to the application of the artificial magnetic oxide of iron either in a dry or moist state suspended in water as a substance well adapted from its extreme susceptibility of mag- netic influence to indicate the direction of magnetic or galvanic currents the magnetic curve described by Dr.Brewster being beau- tifully exemplified by the use of this oxide. 20. “ On the Influence of Water in Chemical Reactions,” by Mr. E. A. Parnell. November 16.-The President in the Chair. Dr. Hare of Philadelphia presented to the Society several copies of his papers *‘ On Tornadoes,” “Chemical Nomenclature,” ind Some Experiments to ascertain the Heating or Cooling Influence of Changes of Density resulting from Changes of Pressure in Dry and Moist Air,” &c. Dr. Charles Schaf haeutl was elected a member of the Society.The following communications were read :-21. ‘I On the Analysis of the Oils of Laurel Turpentine Hyssop, and Assafetida,” by Dr. John Stenhouse. (See Memoirs Vol. I. Art. 7.) 22. An extract from a letter from Dr. Clark “ On the Revision and more exact Determination of Atomic Weights.” Dr. Clark finds that when the proper correction for weighing in a vacuum instead of in air is applied to the weighings made by Berzelius in his experiments on the formation of water by passing hydrogen gas over ignited oxide of ccpper the results are very sen- sibly altered. ‘‘ Berzelius gives ‘‘ Copper (metal) 395.6 Water produced Peroxide of copper 495.6 ... Increase oxygen 100 Hence ;;drop 12.49 But if weighed in a vacuum the increase of 100 for oxygen and the weight of 112.491 for water would both have been greater.The following would be the corrected numbers :-oxygen 100.0266 ; water 113*G13; or oxygen being 100,water will be 112-583. Hcncc 16 hydrogen 12.583 in air 12.491 correction + 0.092. As to Berm- lius and Dulong’s experiments on the specific gravity of gases how- ever strange it is true that the results appear almost all to have been miscalculated. The specific gravity of hydrogen instead of being calculated 0.0687 should have been 0.06986 or with Rud- berg’s dilatation 0.06988. With the received specific gravity of oxygen this would give 12.67 for the equivalent of hydrogen; Dumas’s specific gravity of oxygen would give 12-64. On all these considerations I regard the numbers authorised by the experiments where Berzelius has taken part to be 12.6 for hydrogen.” 23.“ On a more simple and correct Mode of Reducing the Indi- cations of the ordinary Saccharometer and Hydrometer to each other,” by Robert Waringtou Esq. The great utility of some ready means of effecting these opera- tions was first pointed out on the following grounds:-lst from the great variety of saccharometers in general use ; 2ndly from their being constructed of brass which from its liability to loss of weight from abrasion and corrosion causes frequent errors of indication ; 3rdly from some of these instruments as in that employed by the Excise reading off degrees of specific gravity of which the saccha- rometer equivalent is found by referring to a printed table sold with the instrument; and 4thly to the practical chemist from the great cost of these instruments and from his always having in his hands the means of accurately ascertaining the specific gravity of any Pam- ples of worts or other material on which he may be ealled to experi- ment and therefore only requiring a correct formula for reducing such specific gravities to those of the saccharometer.The saccharometer is a hydrometer of great delicacy having its zero point corresponding to the specific gravity of distilled water and its scale which has usually a range of specific gravity from 1.000 to 1.150 divided into 54 principal divisions each of which is again subdivided into 5 or 10 equal parts. The object which is professed to be attained in this instrument is the indicating the number of pounds of saccharine matter contained in “the barrel ” of the infu-sion of malt and other grain.The imperial barrel contains 36 gd-lons of distilled water of 10 pounds each or 360 pounds of water. Of wort whose indication is 1 on the saccharometer a barrel weighs 361 pounds ; 2 on the saccharometer 362 pounds and so on for the 54 divisions of the scale. This instrument does not fulfil its professed object as,-lst it does not indicate directly the absolute quantity of * solid matter per barrel but only the change of density which this occasions ; Bndly it is equally effected by the other ingTedients in the infusion of malt as mucilage vegetable albumen &c. as by its sugar.The eaccharometer must therefore only be regarded as an instrument of comparison. The rule usually followed in calculating the specific gravity from the saccharometer indication is to add 360 the weight of the barrel of water to the saccharomekr indication and then multiply the result 17 by 9-77 ; or 26th~ being the value of each saccharometer pound ex- pressed in terms of specific gravity; 360 multiplied by 2.77’being equal to 1000 the specific gravity of water. Hence if 36 be the observe saccharometer indication the specific gravity is 36 + 360 x 2-77 = 1100. Reversing the operation and dividing the number expressing the specific gravity by 2.77 and then deducting 360 from the result gives of course the saccharometer indication or gravity ; ??,.thus 1100-360 = 36. Many works held in high estimation by way of fachtating this operation have adopted the use of the factor 2.78 but this must of necessity involve error without materially shortening the calculation; some parties have gone so far as to state that 2.7 is a sufEcient approximation ; this however with the gravity taken as an illustration will give an error of 11.4 pounds in excess or 47.4 instead of 36. The rule adopted by the author for converting real specific gmvities or hydrometer indications into saccharometer gra-vities is as follows :-From the specific gravity observed expressed in terms of distilled water as unity deduct 1 and then multiply the result by 360 ; the product is the equivalent saccharometer indication ; thus for specific gravity 2*100 ; 1.100-1.000 x 360 = 36 of the sac- charometer.The saccharometer gravity again is calculated from the real specific gravity by the converse of this operation; divide the eaccharometer indication by 360 and then add 1 ; thus & + 1-OOO = 1.100. December 7.-Richard Phillips Vice-president in the Chair. Mr. Graham presented his ‘* Elements of Chemistry.” Mr. Porrett presented an agglutinated mass of gun-locks screws gun-flints &c. from the late fire at the Tower of London. Robert Smith Ph. D. was elected an Associate Member. The following communications were read :-24. ‘‘ On a new Class of Cacodyl Compounds containing Plati- num,” by Professor Bunsen of Marburg. (See Memoirs Vol. I. Art. 10.). 25.** On the Preparation of Chromic Acid,” by Robert Waring- ton Esq. In the number of L’lnstitut for 9th July 1840 under the head of Proceedings of the Imperial Academy of Sciences of St. Pe-tersburgh,” a notice is given “On an easy process for preparing chromic acid and the manner in which it behaves with sulpliuric acid,” by M. I. Fritzsche. The author pours concentrated sulphuric acid with care into a hot and saturated solution of the bichromate of potash and obtains a voluminous scarlet crystalline precipitate which is separated and dried first by heat then in a vacuum. This is the chromic acid. which must be washed with a small quantity of cold water to remove the mother liquors and sulphuric acid which 18 riiay still adhere to it.As to the compound of sulphuric acid and cbrornic acids described by M. Gay-Lussac in the Annales de Chin& et de Physipe vol. xvi. p. 102 the author says he has ‘I never hen able to make it and is very much disposed to doubt its existence.” On repeating this process I found that the chromic acid does not fall alone but is contaminated by admixture with a considerable quantity of a white saline substance which on exami-nation proved to be the bisulphate of potash and which on account of the great solubility of both these substances as precipitated there is great difficulty in separating. The modification of this process, which I have found to give chromic acid in a crystalline form and nearly in a state of purity is to take 100 measures of a cold satu- rated solution of the bichromate of potash (prepared by hoiling and then allowing the solution to cool and deposit the excess of the salt) and add to this from 120 to 150 measures of concentrated sulphuric acid ; the latter should be free from sulphate of lead as otherwise it will fall as chromate and sulphate of lead with the chromic acid on dilution with the solution of bichromate.The mixture is then al-lowed to cool and the chromic acid gradually crystallizes in beau- tiful dark crimson needles. Decant the fluid part and place the crystals with the adhering sulphuric acid on a thick fiat tile of bis-cuit porcelain ; another tile is then to be placed upon the crystals and the whole submitted to pressure for a considerable time. On removing the chromic acid it will be found in a perfectly dry state and yielding a mere trace of sulphuric acid on examination.26. ‘‘ On the employment of Chromic Acid as an agent in Gal- vanic arrangements,” by Robert Warington Esq. (See Memoirs Vol.I. Art. 9.) December 21.-The President in the Chair. Dr. Lyon Playfair presented the second edition of Liebig’s ‘‘ Che-mistry of Agriculture.” Henry Beaufoy Esq. Thomas S. Thomson Esq. Henry Croft Esq. William Crawhall Esq. Rev. W. Walton Henry Heynolds Esq. John Barnes M.D. John Hutchinson Esq. Thomas Morti- more Esq. were elected members. The following communications were then read :-27. ‘‘ On the Agency of Caloric in permanently modifying the state of Aggregation of the Molecules of Bodies,” by Warren De la Rue Esq.The subeject of tnis short notice is the practical application of the action which takes place in masses composed of palpable particles when raised to a temperature insufficient even for their partial fusion. In illustration of the particular action alluded to may be quoted 19 the following familiar facts :-Precipitated gold wlien heated to a low red heat contracts in volumc becomes more coherent and yellow in colour ; clay contracts in volume when heated and generally in pro-portion to the intensity of the lieat ; the carbonaceous deposit in the inside of gas retorts by the continued action of heat acquires suffi- cient hardness to scratch glass ; ordinary coke and charcoal become harder the longer the action of heat is continued on them; these and many other analogous facts are examples of a new molecular ar-rangement being produced in vwious substances by subjecting them to an increase of temperature not however sufficient for their fusion.To cause the foregoing changes a red heat is employed ; we shall however presently see that a temperature but little above that of boiling water is quite suficient to materially alter the cohesion of some substances. It may be as well here to premise that the particles should be brought as closely as possible together ; to effect this if the sub- stance be in powder it must he made into a paste with water to displace the air and the paste so prepared submitted to a pressure of four tons or upwards on the square inch ; air being so exceedin4 compressible it cannot be got rid of without the use of some liquid.The manner of pressing need not here be entered on the operation being purely mechanical. White lead precipitated by carbonic acid gas from a hot solution of the sub-nitrate always falls as an exceedingly light deposit ; if it be pressed as before described and the pressed cake dried at the or-dinary temperature of the atmoiphere it coheres but imperfectly but on being subjected to a heat of between 200’ and 300’ Fahrenheit it becomes esceedingly hard and compact ; and if the cake be ground up with water and redried it will be found far more dense and opake than the original precipitate showing the change to be permanent. The following fact was communicated to me by hleesrs.Nasmyth and Co. of Patricroft :-Common chalk cannot readily be sawn into thin‘slips as it crunhles under the operation ;if however it be baked at the temperature before named it becomes far more tenacious and may be then cut into any form we choose still heing sufficiently soft for drawing or writing to which purposes it is far more applicable than before baking. Almost all precipitates dry much more crisp at high than at lorn temperatures the agency of heat facilitating the attraction of such particles as may happen to be in contact. In conclusion I may remark that it appears by no means impro-bable that the long-continued action of temperatures but slightly elevated above the ordinary temperature of the atmosphere map have been and still may be the cause of the formation of hard rocks from materials origiiially but slightly coherent.28. “Notice of the Decomposition of Oxalic Methylic rEther (Oxdate of Oxide of Methyl) by Alcohol,” by Henry Croft Esq. While in Berlin I was led to examine the action of potassa on oxalate of methyl by a statement of WeidIuanii and Schweitzer in 20 their first treatise on Wood-spirit; namely that the compounds of the oxide of methyl with acids are decomposed by alkalies not into their constituent acid and wood-spirit as Durnas and Peligot have stated but into the acid and a peculiar oil which they called methol. From this Gwig drew some conclusions unfavourable to the accu- racy of Dumas and Peligot’s research. This statement of Weidmann and Schweitzer I found to be incorrect CUIthey themselves also al- lowed in their second paper.Oxalate of methyl is best prepared by distilling a mixture of 1 part wood-spirit 1 part anhydrous oxalic acid (H 0 $-C,O,) and from ith to Qth of sulphuric acid. The first portion which passes over may be returned and afterwards an-sther part of wood-spirit added or ewn two. The aether obtained must not be allowed to stand in solution for any length of time for it easily decomposes. The above proportions I have found to be the best; the method with oxalic acid alone is troublesome on ac-count of the great volatility of wood-epirit and the length of time required for forming any considerable quantity of the aether. If on the other hand so much as an equal weight of sulphuric acid is taken the mixture becomes brown or black and towards the end of the operation sulphurous acid methol and other products are formed.By passing hydrochloric acid gas into a solution of oxalic acid in wood-spirit no aether could be obtained ; it is possible how.- ever that the result of further experiments may be more favourable only one experiment being made owing to the ve y small quantity of wood-spirit in my possession. It is well known that Mitscherlich formed the oxalovinate of PO-hsa by adding to an alcoholic solution of oxalic aether just so much of an alcoholic solution of potassa as was suflicient to saturate half the oxalic acid contained in the aether. As no acid oxalate of methyl is known I therefore attempted to form it in the same manner but owing to the excessively small quantity of spirit which I possessed, and which is not to be obtained in northern Germany I was obliged to dissolve both the oxalic methylic aether and the potassa in alcohol it appearing very unlikely that the alcohol could have any disturb- ing influence as it is only the aether which ought to be decomposed.On adding the solution of potassa until the mixture became slightly alkaline a white salt in pearly scales was obtained ; this was washed with alcohol and dried. The filtered solution gave more of it on evaporation. In analysing this substance it was useless to attempt to determine the carbon and hydrogen owing to the admitted insecureness of the analyses of potash salts and I had not enough material to prepare either the lead or baryta salt.The oxalic acid and the potassa were therefore alone determined it contained,-lst 30*81,and 2nd 30.76 per cent. of potassa and 46.58 of oxalic acid. I’liis agrees very well with the formula for oxalomethylate of potassa plus one atom of water ; but no water could be driven out by a heat of 150’ C. and I at length found that the salt was only oxalovinate of potash with the composition of which the analyses agree very well :- 21 1. 2. Oxalic acid . . . 46.12 46-58 Potassa . . . 30.04 30.76 30.81. The salts agreed moreover completely in their properties. On re-peating the experiment with wood-spirit instead of alcohol I did not obtain an insoluble salt but on evaporation one which is probably the true oxdomethylate of potash and which I am now ahout exa- mining.Such a decomposition as the above is I believe of very rare oc- currence ; I am not aware of any other instance of it being known although the possibility of some such kind of decomposition has not escaped the acuteness of Berzelius. (Lehrbuch,viii. 703.) We may perhaps suppose that oxdomethylate of potash is first formed but that the attraction of oxalic acid for Ether and of oxalic Ether for oxalate of potash is so strong as to cause the decomposition of hy- drate of &her into its elements when the alcoholic Ether will com-bine with the oxalic acid and the oxide of methyl whose place it takes combines with water to form wood-spirit. That some kind of what is called predisposing affinity is here in play is evident from the fact that oxalate of methyl may be boiled with alcohol for hours without any such change taking place.It may be stated in conclusion that the process last described is a very good and oeconomical method of obtaining the oxalovinate of potassa in a very beautiful form. 29. On the Radical of the Cacodyl Series of Compounds,” by ‘c Professor Bunsen of Marburg. (See Memoirs Vol. I. Art. 8.) January 4 1842.-The President in the Chair. Lectures on Agricultural Chemistry and Geology first part by James F. W.Johnston M.A. was presented by the Author. Michael Faraday D.C.L.,Philip Coffey Esq. Durant Quincey Eeq. were elected members. The following communications were then read :-30.#I On some of the Substances contained in the lichens em- ployed for the preparation of Archil and Cudbear,” by Edward Schunck Esq. (See Memoirs Vol. I. Art. 11.) I‘ 31. On a Rc-arrangement of the Molecules of a body after solidification,” by Robert Warington Esq. (See Memoirs Vol. I. Art. 12,) January 18.-The President in the Chair. Charles Thornton Coathupe Henry M. Noad John Philip, Esquirea were elected members. Colonel Yorke exhibited a specimen of a silver ore from Mexico Ckm. Proc.-No. 11. 22 containing bromide of silver from his collection in confirmation of the late discovery by M.Berthier of the existence of bromine in silver ores. ‘I’he following communications were read :-32. ‘‘ On the Conversion of Benzoic Acid into Hippuric Acid in the Animal Economy,” by Mr.Alfred Baring Garrod of University College. (See Memoirs Vol. I. Art. 13.) 33. (‘On the Constitution of the Sulphates as illustrated by late Thermometrical Researches,” by Thomas Graham Esy.,F.R.S. &c. (See Memoirs Vol. I. Art. 14.) 23 February 1 1842.The President in the Chair. Dr. Bunsen Professor of Chemistry in the University of Marburg was elected a Foreign Member of the Society. The following communication was read :-34. ‘‘ On the Change of Colour in the Biniodide of &Iercnry,” by Robert Urarington Esq. (See Memoirs Vol. I. Art. 15.) February IS.-l’he President in the Chair. The Council declared the names of the gentlemen whom they proposed should retire from the Vice-presidents and Council and those whom they proposed for election.George Knight Jun. Esq. was elected a member of the Society. The following comniunicationa were read :-35. “ On a new Oxalate of Cliromiuin and Potash,” by Henry Croft Esq. (See hlcmoirs I’d.1. Art. 16.) 36. ‘‘ Some Observations on Brewing,” by Septimus Piesse Esq. The author’s attention was directed to the subject by the follow- ing inquiry :-“ Is it possible to obtain a greater quantity of extmct from malt by any other process than that usually followed? Is any thing left in the grains which ought to be in the wort ? ” Now from an esamination of several samples of the malt taken when supposed to be completely exhausted and from the circum- stance of the grairis affording such a large quantity of nourishment to cattle I was led to suspect that it was possible to increase the weight of extract; in fact the grains were found to contain a nota-ble quantity of starch.The non-conversion of this starch into sugar does not depend in the cases I have witnessed upon the use of improper temperatures but ariscs from a deficiency of diastase (the principle which effects the change of starch into sugar). In the ordinary process of brew- ing n certain quantity of water and malt are mixed together of a proper temperature. After standing for a time this water or as it is then termed wort is drained from the malt and a second portion of water is run on to forin the second wort. There can be no doubt but the principal portion of the starch is converted during the first mashing but it never is all.Now it must be remembered that as diastase is soluble it is taken up by the first wort and when that is run off the diastase passes away also. ‘l’he improvement consists simply in adding diastase to the second wort to convert the remain- ing starch into sugar. This is done by the addition of a portion of malt (which contains diastase) previous to mashing a second time. In a brewing of 30 quarters I should take 29 quarters for the first mash and add the remaining quarter to the second. There is such an increase as to warrant me in advising its adoption by it11 brewers and distillers. Chert!* Proc.-No. I1 I. 24 Another improvement in brewing is recommended by the author to prevent the absorption of oxygen by the wort and thus in a great measure prevent acidity.The wort as it flows from the tun passes into the underback according to the usual practice where it is exposed to the air ; and that for some time because the wort must run slowly in order to come bright. The improvement consists in having a float in the back that is a surface of wood the size of the bottom of the back upon which it rests when empty. As the wort runs into the back the float rises with it and falls again when it is pumped up to the copper thus effectually keeping it out of the contact of air previous to boiling when the danger ceases. When this precaution has not been taken 1 have invariably found the wort to indicate more or less acid which may be looked upon as likely to lead to sour beer.March 1.-The President in the Chair. A specimen of sulphuret of lead artificially crystallized from the silver smelting furnaces at the Hacienda de Regla lbf exico was pre- sented by Mr. John Phillips. ‘I’he following communications were read :-37. ‘‘ On the Preparation of Cyanide of Potassium and its appli- cations,” by Professor Liebig of Giessen. (See Memoirs Vol. I. Art. 18.) 39. ‘‘ On the Specific Heat and Conducting Power of Building Materials,” by John Hutchinson Esq. The following is the substance of 1Mr. Hutchinson’s paper :-The author after mentioning the state of our knowledge respecting the conducting powers for heat of different substances proceeds to point out an important source of error in all such investigations hitherto made arising from the neglect of correction for differences of specific heat among the bodiea examined ;the effects observed being evidently mbed efects arising from both causes.‘i’liis being the case before any correct investigation of the relative conducting powers of huild-ing materials referred to could be advantageously undertaken it be-came indispensable to acquire a previous knowledge of their relative capacities for heat in order that correction for differences of this kind might be made. Thisinquiry therefore naturally preceding that of the proper subject of the paper first attracted the author’s attention. The building materials selected for experiment were the following -Oak beech and fir-woods; common facing and fire-brick; As-phalte composition hair and lime mortar lath and plaster Roman cement plaster and sand plaster of Paris Keene’s cement ; slate Yorkshire flag-stone Zunelle marble Napoleon marble Portland and Bath-stone ; and lastly three specimens of the stones now used in building the Houses of Parliament.The plan of experimenting chosen was that known as the ‘‘method 25 of mixture,” this appearing by all evidence on the subject to be the most unobjectionable. The process followed differed but little from that described by Itegnault in his recent researches. A suitable quan- tity of material in fragments being accurately weighed out and placed in a little wire basket with the bulb of a delicate thermometer in the midst the whole was exposed in an inclosure heated by steam until the thermometer ceased to rise when the basket was withdrawn and plunged with suitable precautions into avessel of water at a tempe-rature a little below that of the atmosphere.After the lapse of a very short interval the temperature of the water was carefully ob- served and its rise gave the ~=RS of calculating the specific heat of the substance. The author remarks on the necessity of equalizing as much as pos-sible the times of heating of the different substances having observed a great difference in the results given by the same body when slowly and when quickly raised to the high temperature required for the ex- periment and attributes this difference to an alteration in the state of the currents or waves of heat travelling inwards towards the centre of the solid.A number of minute precautions indispensable to a correct result were also pointed out and exemplified. The results of the investiga- tion were given in a tabular form and the principle of the calculation described. With the knowledge thus obtained the author proceeded with his inquiries respecting the conducting powers of the substances under examination. The plan usually adopted in this kind of research namely ob-serving by the aid of thermometers the time occupied by the passage of a certain amount of heat lengthways through the substance of a prism one end of which was exposed to a high and constant tem- perature having failed on trial with these bodies in consequence of their feeble conducting powers the following method was had re- course to with perfect success :-The various substances examined were cut with the greatest care into cubes of 2.8 inches in the side and a hole drilled in the centre of one of the faces half way through large enough to receive the bulb of an exceedingly sensitive thermo- meter together with a little mercury to improve the contact with the substance of the cube.The temperature of the mass being exactly observed it was next plunged all but its upper surface into a large bath of mercury heated by steam whose temperature remained con- stant at 2 1lo,and the time of rise of the thermometer for every suc- cessive loo accurately noted until the maximum was reached thus affording a comparison of the relative conducting powers or perhaps more properly resistance to the passage of heat towards the centre of the mass.In the course of these experiments a very extraordinary circum- stance was observed ;although the greatest care was taken to equal-ize the temperature of the cubes by suffering them to remain at least twenty -four hours before experimenting in an uniform temperature 26 yet they never exactly acquired that of the room or even agreed among themselves in this respect ; an observation which led the au- thor to the suspicion that the genemlly received doctrine of an equal distribution of secsible heat among bodies in contact and not influ- enced by external sources of disturbance might not prove strictly true but that on the contrary each of a number of different sub- stances exposed under similar circumstances to the influence of a medium of uniform temperature acquires a proper temperature of its own.The same thing was observed with higher degrees of heat ; a mass of slate for example plunged beneath the surface of uniformly heated mercury and maintained there long after the thermometer in the slate had reached its maximum always exhibited a temperature decidedly below that of the surrounding metal. A third series of experiments were made with a view of ascer- taining the relative rates of cooling in air of the various materials examined from a higher temperature to that of the atmosphere. The arrangement consisted of the cubes before described covered externally with thin paper for the eake of uniformity of surface the same delicate thermometer being iuserted in the bole in the centre together with a little mercury for the sake of contact.The cubes were each in turn heated in the steam-chest used for the specific heat experiments until the included thermometer rose to 200° ; they were then removed suspended in the air and the time of fall of tem- perature for every 10 degrees carefully noted. The precautions required to be taken to avoid errors of different kinds were fully described and drawings of the apparatus used ex- hibited together with a most elaborate and complete set of tables embodying the whole of the results. March 15.-Itobert Porrett Esq. in the Chair.Joseph Redtenbacher M.D. Professor of Chemistry in the Uni- versity of Prague was elected a Foreign Member of the Society. Edward Schunck Esq. was elected a member. The following communications were then read :-Second Part of Mr. Hutchinson’s Paper. 39. ‘‘ On the Preparation of artificial Yeast,” by George Fownes Ph.D. (See Memoirs Vol. I. Art. 19.) March SO.-Anniversary Meeting the President in the Chair. The following Report of the Council was read by the President and subsequently ordered for publication. The occasion of the first Anniversary enables the Council to 27 refer to tlle atctisfactorp progress which has been made during the last year in establishing and organizing the Society. ‘l’he rapid imp\Tement and espansion of chemical science which distinguishes tile present time with the estension of its useful applications to physiology to agriculture and in so many other directions excited the originators of the Chemical Society to assist in the impulse which their favourite Ecience had received ; while the increasing public interest in chemical information and the consequent multi- plication of chemical inquirers led them to anticipate the support of a class of men sufficiently numerous to form the basis of a swiety which should insure to the chemists of this country the advantages of association and of mutual co-operation.The resnlt has not dis- appointed the anticipations of its projectors the Chemical Society already containing a body of members sufficiently numerous to insure it8 stability including nearly all the distinguished chemists of the country.The Societyeommenced on the 30th of March last with 77 mem-bers. Since that time 50 members have been elected making in all 127 members. Of these 11s are ordinary members ; 6 asso-ciates ; and 3 foreign members. In the selection of foreign mem- bers the Council has hitherto confined itself to the distinguished individuals who have directly assisted in forwarding the objects of the Society by contributing papers to be read at its meetings. The state of the funds of the Society is satisfactory and will be fully exhibited in the audited accounts of the Treasurer which are appended to this Report. l‘he Council has hitherto restricted the expenditure to the most necessary and useful objects of the Society namely the rent of its place of meeting and the publication and cir- culation of its Transactions.The Socicty first availed itself of the accommodations offered by the Society of Arts. These they were led to abandon from some anticipated inconveniences from restnc- tion to experimenting. Their present accommodations in the Western Literary and Scientific Institution are not orpensire but are liable to objections among which the want of a Council-room and of any place of deposit for the property of the Society are suffi-cient to prevent their being permanently retained. The Council is therefwe again making inquiry for suitable acconmoclations and will report the result to the Society before the Summer recess.‘l’he Society had published Two Parts of Proceedings and hlemoirs the first in June last upon the adjournment of the Society and the second recently in the beginning of February. It had received from the commencement to January the 18th the period included in these publications 33 communications all of them interesting and several of them of great value ; of which 14 are printed entire in the Memoirs and full abstracts given in the Proceedings of the remaining 19. The Council is fully sensible that the utility of the Society and its reputation in the scientific world will mainly depend upon its publications and presses upon mc‘ml)ers who have already contril)utcd the importance of continuing their support and invites similar assistancc from othcrs.‘1’11~hwt tllid* of tiic Society are 28 due to all the contributors to its Transactions more particularlv to those foreign chemists of great eminence who have lent their aid in this way and evinced a friendly interest in the establishment of the Society which is most gratefully acknowledged. The Society has received during the Session several presents of books and interesting specimens from different members with a do- nation of five guineas from Dr. Leeson for which thanks have been returned to the donors. The Council is convinced that donations both of books and specimens would rapidly increase provided a suitable place of deposit were provided for the property of the Society accessible to the members. In selecting a future place of meeting for the Society the possession of such accommodations will therefore be looked upon as an essential requisite.The Council has lately occupied itself with the preparation of a code of laws and regulations for the government of the Society founded upon the practice of other scientific bodies and the experience of last year. This undertaking has been completed and the rules proposed will be brought under review of the Society at the present general meeting. A. AIKIN, Treasurer with the Chemical Society. Dr. .€ s. d. Subscriptions from 70resident members .. 140 0 0 Ditto from 36 non-resident ............. 36 0 0 1 composition ........................ 10 0 0 1 donation. .......................... 5 5 0 6191 5 0 -~ Cr.By printing and engraving.. ............ 7 8 8 -stationery ........................ 7 15 3 -postage and parcels. ................ 3 9 10 -rent ............................... 21 5 0 39 18 9 By balance in the Treasurer’s hands ...... 151 6 3 El91 5 0 Auditor’s Report. I have examined the accounts of the Chemical Society of London presented by Arthur Aikin Esq. as Treasurer and find the monies received to amount to the sum of A185 5s. Od. and the expenditure (for which vouchers have been shown) to amount to the sum of &37 8s. .Id. leaving a balance in the hands of the Treasurer of 6146 16s. 8d. P. N. JOHNSON. London hlarch 11 1842. 29 The following gentlemen were elected as Officers and Council for the ensuing year :-President.-Thos.Graham Esq. Vice-Presidents.-William Thos. Brande Esq. ; John Thos. Cooper Esq. ; Michael Faraday Esq. D.C.L. ; Richard Phillips Esq. Treasurer.-Arthur Aikin Esq. Secretaries.-Robert Warington and George Fownes. Foreign Secretary.-E. F. Teschemacher. Council.-Dr. Thos. Clark ; Dr. Chas. Daubeny ; ,John Fred. Daniell Esq. ; Thos. Everitt Esq. ; W. R. Grove Esq. ; James F. W. Johnston Esq.; Percival N. Johnson Esq.; George Lowe Esq. ; William H. Miller Esq. ; Robert Porrett Esq. ; Dr. G. 0. Rees ; Lieut.-Colonel Philip Yorke. The laws of the Society as drawn up by the Council were sub- mitted to the meeting. and having been read and discussed were confirmed with amendments and ordered to be printed for the use of the members.The thanks of the Society were given to the Officers and Council for their exertions during the past year. April 5.-The President in the Chair. Specimens of &I.Claudet's improvedDaguerreotyped portraits were laid on the table. Mr. W. J. Cock presented to the Society a specimen of native chloride of silver from Mexico. " A Letter to Lord Aberdeen on the state of the Schools of Chea mistry in the United Kingdom," by Wm. Gregory M.D. was pre- sented by the author. " What can be done for English Agriculture," a letter addressed to the Nlarquis of Northampton by James F. W. Johnston MA. &c. was presented by the author. The following communications were then read :-40. Extract from a letter from Wm. H. Miller Eoq. Professor of Mineralogy in the University of Cambridge.'' I regret that my engagements in Cambridge have prevented my being present at the meeting of the Chemical Society especially as I was desirous of offering my services in- determiniog the form of any crystalline products that may present themselves to chemists who are engaged in original researches. Also in return I might make bold to ask some members of the Society to supply me with certain objects of crystallographic and optical research from their laborato- ries." 41. " On the Analysis of the Chalk of the Brighton Cliffs," by Dr. Edw. G. Schweitzer. 30 My attention was directed to the soil of this neighbourhood for the purpose of ascertaining if the chalk contains any ingredient pe- culiarly favourable to the growth of Gramines in consequence of the well-known fact that the herbage of the South Downs along the coast of Sussex affords a superior food for cattle producing meat of excellent quality for which these Downs are justly celebrated.The result of my analysis substantiates the presence of phosphate of lime an ingredient valuable for the nutrition of plants. The chalk is composed of the following substances in 100 parts :-Carbonate of lime ........ 98-57 ...... of magnesia .... 0.38 Phosphate of lime ........ 0.11 Protoxide of iron ........ 0.08 ...... of manganese.. .. 0.06 Alumina.. .............. 0.16 Silica.. ................ eG1 -100~00 To ascertain the quantity of phosphoric acid I followed Dr.Schulze’s method (Journal fur prakt. Chemie xxi. S. 387-389) which he recommends for the analytical investigation of soils. Finding it useful and correct I subjoin an extract from his treatise. The process is based upon the fact that phosphate of lime and phosphate of magnesia are soluble in acetic acid while the phos- phate of peroxide of iron and phosphate of alumina are not so This being the case the soil or mineral is to be treated with hpdro- chloric acid and the iron which the solution contains per-oxidised the phosphate of protoxide of iron being soluble in acetic acid. Should the muriatic solution contain more phosphoric acid than oxideof iron or alumina (which seldom is the case as the latter are usually predominant,) peroxide of iron or alumina is to be added the solution must also be freed from every trace of silica.The earthy murintes are precipitated with ammonia after which acetic acid is added and the whole gently digested. The precipitate will dissolve again with the exception of the phosphates of peroxide of iron and alumina. When both these ingredients enter into the pre- cipitate caustic potassa will give the means of ascertaining their respective quantities. The solubility of the phosphate of protoxide of iron and the inso- lubility of the phosphate of peroxide of iron in acetic acid when freshly precipitated give an excellent method to separate quantita- tively these two degrees of oxidation. The manipulation is obvious. The discovery by Professor Ehrenberg that the Brighton chalk consists of microscopic shells is a decided proof of its animal origin to which may now be added an additional one viz.the presence of phosphate of lime which is a usual although secondary ingredient of the shells of Crustacea. 42. ‘‘ On the Action of Chromate of Potash on the Protosulphate of Manganese,” by Robert Warington Esq. Jn the course of some experiments on tlic formation of double salts of chrcjniic acid with various bases depending on the teiidency which might arise from the resulting aflinities to the formation of certain crystallized combinations the subject of the present brief comniunication came under my notice. On adding a solution of the yellow chromate of potash to one of the protosulphate of manganese no turbidity or precipitate takes place but the mixed fluids become of a deep orange red colour and after a short period the surface is covered with a dark brown crust or film and the whole of the containing vessel is coated with the same substance ; at times when the solutions are dilute this deposit assumes a crystalline appearance.If this compound is prepared under the microscope in the manner described in a former paper the first effect is the appearance of numeroils minute spherical gra- nules of a fine crimson hrown colour which gradually increase in size until about from six to seven 250th~ or *025 of an inch in dia- meter ; a number of delicate crystallized spicuk are then observed to start out in radii from their sides ; and when the solutions em- ployed for its production are diluted fine stellated groups of pris- matic crystals are obtained.When this substance which has a dark chocolate hue is examined by a strong transmitted light it has a rich crimson brown colour it possesses the following proper- ties .-it is soluble in diluted iiitric or sulphuric acids without residue yielding an orange-coloured solution ; when acted upon by hydrochloric acid chlorine is evolved and a brown fluid results which by the addition of a few drops of alcohol or other deoxidizing agent becomes of a fine emerald green. The following analysis was made of it :-8*2 grains previously dried at a temperature of boiling water were submitted to a long-continued red heat in a small green glass tube to which a chloride of calcium tube was attached ; it lost 1.0 grain which corresponded with the weight gained by the absorption tube ; 8.2 grains dissolved in dilute nitric acid and pre- cipitated while boiling by caustic potash gave after the necessary treatment 4.5 grains of the red oxide of manganese ; the solution was then acidified by sulphuric acid and evaporated to dryness to expel the nitric acid redissolved deoxidized by alcohol and the oxide of chromium thrown down by ammonia again evaporated to dryness to avoid the possibility of any of the oxide being in solu-tion and the oxide of chromium well washed gate 2.3 gains.Wc have therefore 4.5 grains red oxide manganese. . = 4.185 protoxide 2.3 ... protoside chromium .. = 3.000 chromic acid 1-0 ...water . . . ... . .... . . 1-000water -8.188 By calculation this should be . . 4.141 protoxide 3.014 chromic acid 1.043 water Or 1 atom chromic acid + 2 atoms protoxide of manganese + 2 atoms water. Represented by Cr 0 + 2 Mil 0. $-2 H. 0 Chern. I-’roc.-No. III. 32 April 19.-Wm. Thos. Brande Esq. Vice-president in the Chair. Mr. Collen exhibited specimens of his calotyped portraits. Mr. H Croft exhibited and described Dr. Bunsen’s new galvanic arrangement. Alfred Baring Garrod Esq. was elected an Associate. The following communications were then read :-43. “ On the Equilibrium of the Temperature of Bodies in con- tact,” by E. A. Parnell Esq. In reference to observations recently made by Mr. Hutchinson on the difficulty of raising the temperature of any substance to the de- gree of the medium by which the heat is applied Mr.Parnell ob- serves “From what I know of the mode in which Mr. Hutchinson operated it is probable that a loss of heat occurred by radiation from the substance operated on ; by radiation first to the cover of the bath and from this to external objects. On adopting precautions to avoid this source of error I found that in a steam-bath the tem- peratures attained by substances were 1. Olive oil. ..... degree below the temperature of the steam. ... ... ... 2. Water.. ...... i!3 And in a water-bath,- 3. Water ....... + degree below the temperature of the water. 4. Vapourof &her 1 ... ... ... 5. Air.. ........ 1 ...... ... In the two first experiments the apparatus used was a large flask closed with a cork having several perforations through one of which was admitted a wide tube containing the liquid operated on the tube not dipping so far as the surface of the water in the flask which was kept boiling. In the remaining three a copper water-bath was employed the water vapour or air being contained in a glass globe of about fif-teen cubic inches capacity having a narrow neck through which the thermometer was admitted. The globe was supported in the bath by a wire-cage in the same manner as is done in the operation of taking the density of vapours. It would hence appear from the proximity of the temperature of the substance heated and the bath that if the experiments were con- tinued a sufficient length of time and every chance of error avoided the substance might be heated to an equal degree and the law of equilibrium of temperature maintain its universality.I could never however raise the temperature of sther vapour nearer than one degree below the temperature of the bath and to effect this required at least half an hour. I would therefore recom- mend in taking the density of vapours that the temperature of the globe be considered as one degree less than that of the bath in making the calculations. Notwithstanding with this correction the weight of the vapour can scarcely be effected to a greater extent than 804 grain. 33 44. ‘‘ On the Preparation of Hippuric Acid,” by Geo. Fownes Esq.Being very desirous of possessing a specimen of a very interesting substance hippuric acid namely and failing to obtain it in any quantity from the horse-urine collected in London stables I was induced to make trial of that of cows and speedily found it to be a substance highly advantageous for the purpose. Perfectly fresh cow-urine presents the aspect of a transparent amber-coloured liquid of peculiar but not disagreeable odour and quite neutral to test-paper. When this is evaporated down in a water-bath to about one-tenth and mixed with hydrochloric acid n very large quantity of a brown crystalline substance separates which is hippuric acid. It is very easy in this way to operate upon whole gallons of the liquid and thus procure many ounces of hip- puric acid.To purify this substance I find the following method very ad- vantageous. The brown rough acid is dissolved in boiling water of which by the way it requires a much larger quantity than from the descriptions given would be imagined and through the solution a stream of chlorine gas is transmitted until the odour of that gas becomes perceptible in the liquid and its brown colour passes into a sort of deep amber-yellow. The hot solution is then filtered through cloth and upon cooling the acid still very impure crystal- lizes out. The acid is next dissolved in a dilute hot solution of carbonate of soda taking care to have a little excess of the alkali digested for a few minutes with a little animal charcoal filtered and lastly the solution strongly acidified by hydrochloric acid which removes the base and sets free the hippuric acid.Should that substance not be by such treatment rendered perfectly white it may be again dissolved in hot water a little chlorine passed the solution supersaturated with carbonate of soda digested with animal charcoal and once more decomposed by an acid. . It is to be observed that hippuric acid only crystallizes in a distinct and characteristic manner when pure or at least when in a condition approaching that state ; under other circumstances it usually separates either as short radiated needles or as a granular crystalline powder. The latter happens when soluble salt is present. If the urine instea2 of being quite fresh is at all ammoniacal then during the evaporation a very large quantity of ammonia is disengaged accompanied by slow effervescence and the liquid affords as Liebig has already pointed out benzoic acid only with- out a trace of hippuric.The great density of the urine of the cow is a remarkable circum- stance ; one sample affording much hippuric acid gave the sp. gr. of 1.0325,which is considerably higher than that of human urine. This density is chiefly due to a most prodigious quantity of urea which is easily extracted from the brown liquid remaining after the separation of the hippuric acid by the aid of il hot strong solution of 34 oxalic acid which throws down the slightly soluble oxalate. This can bc decomposed by chalk and the urea extracted without having recourse to alcohol.Besides these two substances hippuric acid or rather hippurate of an alkali and urea cow-urine contains a little uric acid phosphates and other salts in tolerable abundance. The constant occurrence of so much urea in the urine of all ani- mals both granivorous and flesh-eating tends greatly to strengthen the opinion that it is by this channel almost alone that the removal of those portions of the azotized constituents of the body which have been worn out as it were or in the act of undergoing decay is effected. It is well known that such substances by ordinary putre- faction furnish carbonate of ammonia ;but in the body this process seems to have been modified in such a manner that in place of that substance urea or carbamide is generated which is destitute of the irritating power upon the orgms which a corresponding quantity of the ammoniacal salt would possess.It has been suggested that hippuric acid is not a direct product of the animal system but is formed by the union of benzoic acid or its elements with those of lactate of urea the benzoic acid being present in the food and the recent experiments of Mr. Garrod cer- tainly countenance the opinion. But these attempts to detect ben- zoic acid in the food of these animals were in the hands of Liebig quite unsuccessful and it seems unlikely that it would be found at any rate in considerable quantity in such substances as grains and mangel-wurzel which with the addition of a little hay consti- tuted the food of the cows from which such an abundant supply of hippuric acid was obtained.There is only one other point which requires notice and that is the nature of the change which hippuric acid so readily undergoes by putrefaction. It is astonishing that a substance which so pow-erfully resists the action of chlorine should be so easily affected by simple contact with piitrefying matter. A glance at the composition of hippuric acid will show that this change is altogether different from that which urea sufTers under similar circumstances the assimilation namely of the elements of water by which it becomes carbonate of ammonia. Hippuric acid on the coiitrary seems to pass into benzoic by an absorption of oxygen from the air carbonic acid and ammonia being at the same time produced.Hippuric acid.. . . C, H N 0, Subtract-Benzoic acid ... . . C, H 0 which by addition of 6 cq. of oxygen from the air would furnish I cq. ammonia and 4 rq. carbonic acid. 35 May 3.-John 'rhos. Cooper Esq. Vice-president in the Chair. Mr. Cooper Jun. exhibited specimens of photographic pictures taken by the process of Mr. Beard. The following communication was then made :-45. '' On a curious Formation of Prussian Blue," by Robert Porrett Esq. Mr. Porrett was led to attend to this subject by an observation accidentally made while walking in the garden of a frienq. He found that a great number of the pebbles in the gravel walk were tinged of a fine bright blue colour; and on remarking the appear- ance to the owner and inquiring as to the cause though it had never before attracted notice he ascertained that before the fresh gravel had been laid down the walks had been strewed with some refuse lime from the gas-works for the purpose of destroying the worms and over which the red gravel of the neighbourhood of London had been placed only a few weeks before the appearances described were observed.The blue colour was entirely confined to the upper surface of the pebbles which was exposed to the atmospheric air and was found to be Prussian blue. The pebbles affected were siliceous having a white exterior coating. Mr. Porrett considers this production of Prussian blue to have arisen from some of the gas-lime having been dropped accidentally on the surface of the new gravel and that the peroxide of iron there found had been deoxidized by some of the sulphur compounds contained in the gas-lime giving rise to the formation of a combination of iron with cyanogen also present in the lime and calcium and that this compound had been decomposed by the action of the carbonic acid of the atmosphere or by the siliceous matter of the stone and thus causing the formation of the Prussian blue.May 17.-Wm. Thos. Brande Esq. Vice-president in the Chair. Mr. U'arington exhibited preparations of the various forms of the chromates and bichromates of silver. Mr. Porrett presented to the Society a number of the pebbles tinged with Prussian blue described at the previous meeting. Dr. Clark presented to the Society an improved ps-burner for a laboratory table.Dr. Edw. G. Schweitzer William Bacon Esq. and Mr. John Turner were elected members of the Society. The following communications were then read :-46. Extract from a letter froin Professor Clark. 'a The burner is to bc fixed into a table by screwing thereto the cir- 36 cular projectionff. There are two stop-cocks. The horizontal one g is for admitting the supply of gas which passes up the fixed tubepp into the sliding tube m m. Between the outer fixed tube t t and the inner fixed tube pp,water is contained to serve as a lute to m\ confine the gas. The sliding tube is kept at whatever height it may be placed by means of a spring inserted in a stuffing-box formed by the screw ss aboveff.The spring is represented apart r. It is formed out of a short bit of another metallic tube of such bore as a only to permit the tube rn m to slide through it easily. Four holes in the circle of the wider tube r are bored$ at equal distances and a vertical slit is cut by a saw . from each hole through to the bottom of the tube. After being thus cut the cut parts are squeezed to- gether by the hand and the tube r being put over the tube m and confined in the stuffing-box at s,forms ir convenient spring for keeping the sliding tube m at whatever height it may be placed. The stop-cock w is to let out any water that may by accident get into the tube pp. The tube m m should not be less than half an inch in diameter. The burner b which is copied after one in Professor Graham’s laboratory Uni- versity College burns after the manner of a rose-burner but it is in the form of a ring instead of being solid.It may be called a ring-burner. It per- mits a much more free access of air especially when the flame is placed very close to a vessel. This burner also supplies gas very advantageously for mixture with air in a cylinder at the top of which the mixture burns over wire gauze. The sliding tube relieves the operator from all-cumbrous supports to his burner or from the necessity of having moveable supports to the vessels to be heated. A ring supported by three lem. the whnle made nf tinned irnn. affnrds a chean. -I--3-,_--..-------__---,-------rp stable and convenient support tQ vessels although of considerable weight.” 47.rr On some Salts of Cadmium,” by Henry Croft Esq. (See Memoirs Art. 20. Vol. I.) 6 48. ‘I An Examination of two specimens of South Sea Guano imported for agricultural use,” by George Fownes Esq. No 1.-Presented tho aspect of a pale-brown soft powder with a few lumps having in their inside whitish specks ; its odour was exceedingly offensive. Treated with hot water and filtered it gave a yellow feebly alka- line solution not rendered turbid to any extent by the addition of acid which contained much ammoniacal salt some sulphate and chloride a very large quantity of oxalate and both potash and soda the latter most abundant. 37 The undissolved substance appeared to be a mixture of uric acid earthy phosphates and brown organic matter.Fifty grains of guano by incineration in a platinum vessel left 16.9 grs. fine greyish white-ash. This ash treated with hot water and the whole placed on a filter left a quantity of insoluble matter weighing after being well Washed dried and ignited 14.6 grs. this was almost entirely soluble in warm dilute hydrochloric acid precipitated by the addition of ammonia and evidently consisted of phosphates of lime and magnesia. The aqueous solution was slightly alkaline contained much chlo- ride some sulphate a very notable quantity of soluble phosphate some potash and a good deal of soda. Hence the following approximate result :-Oxalate of ammonia with trace of carbonate undecomposed uric acid brown organic mat- 33.1 66.2 ter and water ........................} Earthy phosphates with very little sandy matter 14.6 29.2 Alkaline phosphate and chloride with little} 2.3 4,6 sulphate ............................50-100.0 No. 2.-Darker in colour and having but little smell. Examined as in preceding case ; it contained no uric acid. Fifty grains gave- Oxalate of ammonia with little carbonate or-} 22a3 44.6 ganic matter and water ................ Earthy phosphates with little gritty matter. . 20.6 41.2 Alkaline sulphates chlorides and phosphates (both potash and soda the latter most abun- 7.1 14.2 dant). ............................... - 1-50-100' The last specimen is evidently older and in a more advanced state of decomposition than the other ; its odour is far less powerful and offensive ; it contains little or no uric acid but a larger proportion of inorganic substances.It is difficult to imagine a manure better fitted for almost uni- versal use than this ''guano ;" it contains in a highly concentrated form everything that plants require for their sustenance with the exception perhaps of potash which however is often abundantly supplied by a soil poor in other respects. The presence of a large quantity of oxalate of ammonia is a cu-rious fact and was early noticed ; there can be no doubt that this substance owes its existence in some way or other to the uric acid contained in the excrement of the sea-birds to the decomposition of which the guano-deposits are due.We can easily imagine that in this mass of putrefying substance kept in a moistened state by the dews of night a decomposition of a peculiar kind may be set up in the uric acid and its gradual conversion into new products among which may easily be oxalate of ammonia effected perhaps somewhat after the following fashion :- Uric acid.. ......C H N90 2 eq. oxal. acid C4 4 eq. water ...... H o,} =(2 .. ammonia H,N 0 1 eq. oxyg. from air 0 1 . . cub. acid C 0 H6 N 0 c5HI3 N 0, c5 This view it must be remembered is merely hypothetical yet is borne out by the facts. The only case in which oxalic acid is known to arise from uric acid is in the artificial farmation of allantoin discovered by Liebig and in which uric acid water and peroxide of lead being boiled together give rise to oxalate of the protoxide of lead allantoin and urea; it is in short an oxidizing action so far resembling the one imagined but more complex.Uric acid (doubled) C, H N 0 Allantoin.. ..C H N 0 3 eq. water. ..... H oJ}={Urea .......C H,N,O 2. .ox. from perox. 0 2 eq.oxa1. acid C p-CI,H,N,O, C,,H,N,O, It is very unlikely that this peculiar mode of decomposition should occur under the circumstances in which the guano is pro-duced ; urea certainly would not resist destruction a week and no doubt the allantoin would share the same fate. It was thought worth while nevertheless to examine one of the specimens (No. 1) carefully for these two bodies a portion of the substance being acted upon by hot water and the filtered solution cautiously evaporated to a small bulk whereupon crystals were abundantly formed on cooling.These being dissolved in hot water decolorized with animal charcoal and the solution once more con- centrated a second crop was got but slightly coloured. These however turned out on examination to be nothing but oxalate of ammonia. The search for urea was equally unsuccessful. There is a curious relationship between the three bodies oxalate of ammonia oxamide and allantoin the only difference in compo- sition being the diminishing proportion of the elements of water. Anhydrous oxdate of ammonia (doubled) .. C H6 N 0 Oxamide (doubled) .................... C H,N,O Allantoin ........................... C H N 0 49. “On the production of Artificial Uranite,” by W.J.Cock Esq. The subject of the present communication was observed during the preparation of the oxide of uranium from its mineral Pitchblende ; it was obtained as follows :-The mineral was pulverized and well calcined; it was then di-gested with diluted nitric acid which dissolved the greater part of the soluble contents. (From this solution none of the precipitate was obtained.) The undissolved residuum was washed and dried and again cal- cined. It was digested in nitric acid rather stronger than before. and gave a solution of a darker green than the first. This solution was left several weeks in open vessels. and upon its being drawn off 39 a quantity uf the grwn prccil)itate was found adhering to the bottom and sitles of the Y.CJSSC:~$.‘L’lie composition which is veryv;viable,of the mineral Pitchblende as given by Kerthier in his Trait; des Essnis pm-Icc voie sechc from two analyses is in the 100 parts,-. Protoside of uranium ............ 51.6 G0.O Carbonate of magnesia. ........... Peroxide of iron ................ 3.3 7.2 2-5 Alumina (clay). ................. Sulphuret of iron and copper ...... Arsenical pyrites (iron) .......... Sulphuret of lead.. .............. 17.2 5.8 6.0 1.2 9.05.5 9.9 3.5 Sulphuret of zinc. ............... Carbonate of lime. ............... 2.2 1.4 2.2 Water and bitumen ............. 4.2 5.2 98.7 95.5 No mention is here made of the phosphoric acid which enters into the composition of the artificial uranite.The composition of the nn- tive urnnite as also of the double phosphate of uranium and copper (chalkolite) are thus given by Rerzelius :-Uranite. Chalkolite. Oxide of uranium ............ 59-37 60.25 Lime.. ..................... 5.65 Oxide of copper .............. s.44 Barytes ................... 1*.51 Magnesia and oxide of manganese * 19 Phosphoric acid .............. 14.63 15.56 Water. ..................... 14.90 15.05 Gangue .................... 2.55 -70 Fluoric acid and oxide of tin .... trace _I_ 99.10 100-It appcars that these two minerals are found mixed together in all proportions and from the artificial compound which forms the sub. ject of the present notice containing both oxide of copper and lime that it is also n mixture of these salts.The following Analysis of the *‘ Artificial Uranite,” inade under the superintendence of Mr. Parnell u7as read as an appendix to the above :-Phosphate of uranium .............. 33. Oxide of copper .................... 19.5 Lime ............................ 1.8 Water.. .......................... 21.5 Phosphoric acid in combination with 8.2 oxidc of copper anti lime (loss) .... ~ 1 1 oo*oo The process of analysis was the following :-(1.) Having previously ascertained by a qualitative analysis that the sole constituents of the sul)stance arc phosphoric acid peroxide Chem. Pror.-No. 111. 40 of uranium oxide of copper lime and water a known weight was dissolved in hydrochloric acid and copper was precipitated as sul-phuret by transmitting sulphuretted hydrogen gas through the solu- tion.The precipitated sulphuret when filtered and washed was digested in nitric acid and from the solution thus obtained oxide of copper was precipitated by potash washed ignited and weighed. (2.) The solution separated by filrration from the sulphuret of copper was next evaporated to dryness and mixed with a little con- centrated sulphuric acid to convert phosphate of lime into sulphate the mixture was diluted with alcohol in which sulphate of lime is quite insoluble and filtered. The sulphate of lime was washed with alcohol dried ignited and weighed. (3.) The filtered alcoholic solution containing phosphate of ura-nium dissolved-in the excess of sulphuric acid was evaporated to dryness the residue digested in nitric acid and phosphate of ura-nium precipitated from the acid solution by ammonia.This when washed and dried was gently ignited and weighed. (4.) The water contained in the substance was determined by ob- serving what loss in weight it sustained when calcined at a dull red heat; and (5.) The remaining ingredient the phosphoric acid in comhina- tion with oxide of copper and lime was considered as the deficiency on the weight of the original substance. 50. ‘‘Some additional Observations on the Red Oxalate of Chro-mium and Potash,” by Robert Warington Esq. (See Memoirs Art. 17 Vol. I.) 41 November 1 1842.-The President in the Chair. “ A Treatise on Crystallography,” by W~lliam Hallows Miller F.R.S.Professor of Mineralogy in ft. John s College Cambridge was presented by the author. “ On the Heat developed during the Combination of Acids and Bases,” by Thomas Andrews M.D. from the author. “Experimental Inquiries regarding Gravitation,” by James Scrym- gour Esq. from the author. “ Objections to Mr. Redfield’s Theory of Storms,” by Dr. Hare and “A Letter to William Whewell M.A.,” by Or. Hare from the author. A number of copies of these two papers was presented by the author for distribution among the members of the Society. ‘6 No. 1. of the Chemical Gazette,” by Messrs. W. Francis and Henry Croft from the editors. “ A Word or Two on Guano,’’ by W. H. Potter from the author. “ Is Selenium a true Element ?” by S. Pieese from the author.Mr. Warington presented part of a cast-iron grating which had been subjected to the occasional action of slightly acid liquids for several years and which exhibited the partial removal of the metal while the residual graphite retained the original form. Charles D’Epinay Esq. William Francis Esq. and E. A. Pmell Esq. were elected Members of this Society and Mr. Matthew Red- mond an Associate. William Thomas Brande Esq. F.R.S. Vice-president having taken the Chair the following communications were then read :-51. “ On Heat of Combinations,” Part I. by ‘Thomas Graham. Esq. F.R.S. (See Memoirs Art. 21. Vol. I.) 52. “ On Pyrogallic Acid,” by John Stenhouse Ph.D. (See Memoirs Art. 22. Vol. I.) 53. ‘‘ On the Analysis of Organic Substances containing Nitro- gen,” by George Fownes Ph.D.The circumstance which led to the present note on the analysis of azotized organic bodies was an attack lately made by M. Reiset on the new method of determining the nitrogen in such cnsee,put into practice with great apparent success by MM. Will and Varren- trapp of Giessen. After drawing a favourable contrast hetween the new method and those previously in use when the propcution of nitrogen to be determined is small the author proceeds to inquire into the validity of the objections before alluded to. It is stated by M. Reieet that when sugar is burned with the usual mixture of hydrate of soda and lime in fine powder and the gases evolved conducted into hydro-chloric acid an addition of pure chloride of platinum and evapora- tion to dryness gives rise to a quantity of the double chloride of platinum and ammonium indicating in some experiments 1 to 1.5 per cent.of nitrogen in the body analysed ;and as this was considered too great to be attributed to accidental impurity it was ascribed to the absorption of the nitrogen of the air contained in the tube by Chern. Proc.-No. 11‘. the mixture of carbonaceous matter and alkali and the subacquent conversion of the cyanide so formed into ammcnia ; and this idea was strengthened by repeating the experiment with the tube filled with hydrogen instead of air when the production of ammonia was found to be lessened. It became important to know how this very serious objection could be disposed of.On repeating the experiment it was found that when the finest white sugar-candy was thus burned a certain quantity of the yellow platinum salt always remained upon the filter after washing with the mixtui-e of alcohol and ather but this quantity instead of indicating 1 per cent. or more of nitrogen in the sugar gave in three exye- rinients only -06per cent. a quantity attributable to impurity. Tartaric acid. and charcoal made from white sugar gave similar results the ammonia amounting to a mere trace doubtless due to foreign admixture. It is difficult from such experiments to avoid drawing the con-clusion that the appearance of the nitrogen is in all such cases due to accidental impurity in the body hurned and not to any direct or indirect formation of ammonia from the nitrogen of the air.To those practising the new method under discussion the fol-lowing observation may be useful :-in mixing the organic matter with the alkali in a smooth porcelain mortar some inconvenience is experienced in the obstinate adhesion of some of the mixture to the hottoin of the mortar and also to the pestle and which is often with difficulty remorcd by triturating two or three small successive por- tions of dry soda-mixture ;the powder is too soft to cleanse perfectly the mortar and a little left behind would necessarily occasion loss in the ultimate result. By the use of a few grains of finely powdered glass this inconvenience is obviated ; the glass is rubbed for a few seconds in the mortar which it cleanses in the most complete man- ner and can then be transferred to the rest of the mixture in the tube where its presence can occasion no injury whatever.As additional testimony to the value of the new method Dr. Fownes subjoins the results of a sct of experiments made by himself with a view of testing the process before venturing to employ it upon bodies of yet unltnown composition :-Uric Aid. I. 2. 3". 4". Substance ................. 4-99 5-14 5.21 5-45 Platinum salt with filter. ..... 95-14 30.2 30.53 31.62 Filter .................... 3.13 3.29 3-28 3.12 26.01 26-91 27.25 2$-5 Nitrogen .............. 1*63OG 1.70'75 1.729 1.808 PCTcent. .............. 33.08 33.22 33.19 33-19 'l'heorc tical per- centage. ......... 3;3*3G Mixed with 4 grains of sugar.43 Urea with a little sugar. Substance ........................ 4.17 Platinum salt with filter ............ 34. Filter ........................... 3-35-30.65 Nitrogen ........................ 1.945 Percent. ........................ 16-64 Theoretical quantity.. .... 46.78 Hippuric Acid. 1. 2. Substance ............ 8.85 8.24 Platinum salt and filter .. 14.17 13.43 Filter ................ 3.44-10.73 3.23-1 0.2 Nitrogen ............. -6809 *64729 Per cent. .............. 7.7 7.85 By theory ............ 7.82 Allantoin with a little’bugar. 1. 2. I Substance. ............. 8-23 5.47 Platinum salt .......... 45.61 30.47 Per-centage of nitrogen .. 35.17 3503.5 Theoretical quantity...... 35.5 November 15 .-The President in the Chair. ‘‘Elements of Chemical Analysis,” by E. A. Parnell Esq. pre-sented by the author. ‘‘ Taylor’s Calendar of the Meetings of the Scientific Bodies of London for 1842-43,’’ from the editor. A Specimen of sublimed arsenious acid in crystals was presented by Mr. Robert U’arington. Dr. Andrew Fpfe was elected ZL Member of the Society. r, I he following communications were read :-54. “ On some Astringent Substances as Sources of Pyrogallic Acid,” by John Stenhouse P1i.D. (See Memoirs Art. 23. J’ol. I.) 55. “ On some new Cases of Galranic Action and on the Con- struction of a Battery without the use of oxidizable Xfetds,” by Alex-ander It. Arrott Esq. (See Memoirs Art. 24 1‘01. 1.) Decemim-6.-’i’lie President in the Chair Nurnerous specimens of rnrc chcmicul products were exliibi ted by Mr.Lovd Nullocl;. 44 The President exhibited a stereotyped plate which had undergone a secondary crystallization By exposure to a damp atmosphere in contact with paper. “ The Chemical Gazette ” as continued was presented by the editors. “ Sur l’huile essentieUe de Bouleau,” par M. A. Sobrero presented by Thomas George Tilley Esq. The following communications were read :-56. Extract from a letter from Dr. Will dated Giessen November 10 1842. “I have repeated Reiset’a experiments on the combustion of sub- stances free from nitrogen with caustic soda and lime. The result is that his statements are incorrect. There is not a trace of am-monia formed if the alkaline mixture as well as the employed sub- stances is quite pure so that Reiset’s observations are not at all an objection to our method for determining nitrogen.I believe Keiset’s alkaline mixture contained nitre or something else othervise he could not have obtained such results. ‘< From my experiments I was led also to repeat Faraday’s in- vestigations on the formation of ammonia and believe I shall find the cause why he sometides obtained ammonia and sometimes not by heating non-nitrogenous organic substances or zinc with hydrate of potash.” 57. ‘‘On fithogen and the Bthonides,” by William H. Balmain Esq. (See Memoirs Art. 25. Vol. I.) 58. ‘‘Report of some Experiments with Saline Manures contain- ing Nitrogen conducted on the Manor Farm Havering-atte-Bower Essex,” by M.W. F. Chatterly Esq. (See Memoirs Art. 26,Vol. I.) December 20.-Wm. Thos. Brande Esq. F.R.S. Vice-president in the Chair. The following gentlemen were elected Members :-Robert Howard Esq. ;John F. Macfarlane Esq. ;Loyd Bullock Esq. ; and Mr.l.5’. H. Balmain as an Associate. The following commuhications were read :-59. On the Division by Three of the Equivalents of the Phosphorus Family of Elements,” by Thomas Graham Esq. F.R.S. (See Me-moirs Art. 21. Vol. I.) 60. “Remarks on the Determination of Nitrogen in Organic Ana- lysis,” by W. Francis Esq. The presence of nitrogen in picrotoxine having been denied by all experimenters the author was induced to repeat with great care the analysis of that substance in the course of which researches abundant evidence of nitrogen ~‘~1s obtained.A few grains of pure picrotoxine heated in a tube with a iittle of the mixture of lime and hydrate of soda give off vapours which quickly restored the blue colour to reddened litmus paper ; the smell of ammonia was also quite distinct. 45 An analysis being made by the method of Messrs. Will and Var-rentrapp in order to determine the amount of nitrogen distinct yel- low crystals of the double chloride of platinum and ammonium were obtained corresponding in one experiment to 1.3 per cent. of nitro-gen and in a second to 0.7.5 per cent. Burned with oxide of copper numbers representing the carbon and hydrogen came out closely corresponding to the results obtained by Regnault.The observations of hl. Reiset in a late Nuniber of the ‘ Annales cie Chim. et de Phys.,’ threw sbme doubts upoii the value of the ana- lytical method above mentioned and the author was led in conse- quence to repeat the experiment on a specimen of. carefully purified sugar 1.649 sugar gave 0.048 of a brownish black substance on the filter wlhh calculated as the salt of ammonio-chloride of platinum gives 0.24per cerit. of nitrogen ; on being burnt it left 0.035 which calculated as metallic platina = 0.30 per cent. nitrogen; ‘2.130 sugar gave 0.053 of the black substance and when burnt 0.31 of platina affording in the one case 0.13 iii the other 0.20 per cent. as nitro-gen. ’The sugar to ensure purity had been crystallized twice out of an aqueous solution again dissolved and thrown down by alcohol collected and recrystallized out of water.A small quantity of it heated with some of the alkaline mixture in a test-tube afforded vapours which did not effect the red colour of litmus paper. Fre.. quently in analyses by this method especially when the organic substance is very rich in carbon fluid carburetted hydrogens distil over which remain behind on evaporation forming a black residue. This is not n.holly dissolved on edulcorsting4mith Fether and alcohol and goes to increase the weight of platinum salt if there be any. Tlie residue reinailling on tlie filter after edulcoration 11ith alcohol and =they in the second experiment did not exhibit under the microscope the least trace of the yeiloiv crystalline silt but IVRS of a blackish brown aniorphous apl:earmce.It iqqm~rs,therefore that the sub- stnnce calculntcd djove as aiiinionio-chloride of platinum was most probably platinum ~vhiciiIind becw reduced by these carburetted li!-clrogeus during evaporation. An analysis of osnniitlc by the new process gave an excellent result the per-centage of nitrogen falling jut below the theoretical quantity. 61. “ On the Sugar of the Eucalyptus,” by James F.IY.Jolin-ston Eq. F.K.S. (See Memoirs Art. 2i Vol. I.) G2. “ On tlie probable existence of Xitrogen conibiiied with Sili- con iii Soils and other Substances,” by IT. H. Ealmain Eeq. The stability of the compounds of boroii and silicon 11 ith nitrogen aiid the facility with wliich such compounds are produced when or-canic mntter is stroiigly lieated with a horate or silicatc seemed to render it probable tlint such bodies might occasionally exist in un- expected circumstances its in soils or ixiiicr‘tk for csttinplc and es-perinients wrc inadc with a view of directly wxrtaiiiing u-hether this uxs the ~ 2 1 ~ .of SCY~~I.~~~ Sainl~lc~ vdi icties ot soil were boil2cl tot’ w);iich tinit>~vitli 46 a mixture of dilute sulphuric and nitric acids then washed and dried and subjected to the action of hydrate of potash at a high tempera- ture ; ammonia was in all cases abundantly disengaged even after the purified soil had been heated to redness. In one instance the sample of soil was boiled with strong nitric acid as long as nitrous acid vapours were generated then submitted to the action of di-lute sulphuric acid washed again boiled with strong solution of caustic potash washed and then agitated with chlorine gas ; yet on being heated with hydrate of potash it gave off ammonia abundantly.It was inferred by the author that the nitrogen ultimately found was in combination with silicon and in that condition had resisted the action of the various agents employed for its removal. January 3 1813.-The President in the Chair Mr. John Turner presented a specimen of anhydrous sulphuric acid for the Society’s Museum and Mr. Robert Warington speci- mens of iodide of potassium and the double tartrate of potash and soda in fine crystals.R. H. Brett Ph.D. William Tudor Esq. and Charles Glassford Esq. were elected Members ; and Messrv. Alexander R. Arrott John Thomas Way and Septimus Piesse Associates The following communications were read :-63. “ On Palladium its Extraction and Alloys,” by W. J. Cock Esq. (See Memoirs Art. 28. Vol. I.) 64. ‘‘ On the Formation of Fat in the Animal Body,” by Justus Liebig M.D. (See Memoirs Art. 29. Vol. I.) January 10.-The President in the Chair. Agricultural Chemistry,” Part First by Thomas George Tilley was presented by the author. John Furze Esq. John W. Nyren Esq. and W. L. Metcalfe Esq. were elected Members. The following communication was read :-65. ‘‘ On the Formation of Milk in the Animal Economy,” by Lyon Playfair Ph.D. (See Memoirs Art.30. Vol. I.) February ’I.-Arthur Aikin Esq. Treasurer in the Chair. ‘‘Proceedings of the Glasgow Philosophical Society for 1841 and 1842,’y from the Society ; and two pamphlets ‘* On the Voltaic Cur- rent add Force,” by Alfred Smee were presented by the author with copies for distribution among the Members. . The following gentlemen were elected Members :-John Forster Esq. Edward €tea Esq. Paul De laRue Esq. and Isham Baggs Esq. The following communications were read :-66. " On a new Method of obtaining pure Silver in the hletallic Spate or in the Form of Oxide," by WilliamGregory M.D. F.R.S.E. (See Memoirs Art. 31. Vol. 1.) 67. '' Some Experimental Observations on the formation of Prus-sian Blue upon the surface of Gravel through the medium of Ferro- cyanide of Calcium." By Robert Warington.In a communication formerly made to the Society by Mr. Porrett on the above subject" that gentleman considered the production of prussian blue to have arisen from some of the gas-lime employed to destroy the wornis &c. arid placed under the fresh gravel having been accidentally dropped on the surface and that the peroxide of iron contained in the gravel had been deoxidized by some of the sulphur compounds of the gas-lime giving rise to the formation of a combination of iron with cyanogen and calcium and that this compound had been decomposed by the action of the carbonic acid of the atmosphere or by the siliceous matter of the stone thus causing the formation of prussian blue.An artificial ferrocyanide of calcium was formed by mixing hydrate of lime and prussian blue to the consistence of a cream ; and this was placed in an open part of a garden and numerous white-coated siliceous pebbles selected from the red gravel of the neighbourhood of London then partly immersed in the mixture so that the upper surfaces might be ex-posed to the action of the atmosphere and moisture ; in a few days the sides of the pebbles assumed the blue colour which gradually spread itself to the summits having the same bright tint as the pebbles presented to the Society by Mr. Porrett proving therefore that the ferrocyanide had been drawn to the surface either by that curious species of crystalline growth if the expression may be allowed which is exhibited by so many saline combinations during their crystallization or by capillary attraction united with evapora- tion from the exposed parts of the pebbles thus rendering it evident that the ferrocyanide might reach the summit of the gravel from below.Other substances were then submitted to the same action to de- cide the question as to the siliceous matter of the stones being in any way instrumental in the production of colour. White limestone pebbles from the south coast of Devon and baked pipe-clay un- derwent the same changes with the exception that the blue tint was not so bright and clear as was the case on the siliceous surface ; but this is considered attributable more to the perfect whiteness of the siliceous coating aiid the decidedly superficial film of prussian blue which was produced on it.Independent of this the effect can only be attributable to the action of the carbonic acid gas present in the atmosphere slowly deconipoeing the ferrocpatiide of calcium and generating the blue stain. 6s. " On the Preparation of Malic Acid from Culinary Ithubarb," by Thomas Everitt Esq. (See Memoirs Art. 32. Vol. I.) * See Proceedings of Chemical Society p. 35. rol. i. 48 February 21 .--?‘he President in the Chair. Mr. James Napier was elected an Associate Member. The following gentlemen were proposed by the Council as Officers and Members of Council for the ensuing year in the room of those who retire in accordance with laws Nos. 1,2 and G :-Arthur Ailtin Esq. President ; Thomas Graham Esq.Vice-President ; Robert Porrett Esq. Treasurer;Michael Faraday D.C.L. William Gregory M.D. William Hasledine Pepys Esq. John P. Gassiot Esq. and W. 1-3. Leeson M.D. as Members of Council. The following communications were read :-69. “A short Notice from NIr. Francis announcing the separation of Theine from the Ilex Paraguayensis or Yaraguay ‘Fen,” by Dr. Stenhouse. 70. Extract from a letter from Professor Henry Croft “ On the Manufacture of Sugar from the Zea Mays.” Experiments have been made in the State of Indiana which seem fully to prove that the stalks of the maize may be employed advan- tageously for the manufacture of sugar. It is well known that the sugar-cane as grown in Louisiana does not produce abovc one-third as much saccharine matter as when raised in Cuba and other tropical situations.In Louisiana one acre yields from 900 to 1000 11)s. of sugar and it appears that 1000lbs. inay be obtained from the stalks of the maize. The juice of the latter contains more than three times as much sugnr as the juice of the bect-root and five times that of the maple. By plucking off the ears of the maize as they begin to form the saccharine matter of the stalk is grcatIy increased. The maize-stalks require less pressure and the whole of the stalk can be used afterwards affording a good fodder for cattle. Thc plant can be raised with the greatest ease in from seventy to ninety days whereas the sugar-cane requires much care and attention and does not arrive at maturity in less than eighteen months.49 March 7.-.lohn T. Cooper Esq. Vice-President in the Chair. James Thomson Esy. F.R.S. Edmund P. Thornson Esq. Charles l’homson Esq. William Stilrk Esq. .Jncoh Bell Esq.. and George Gow Jun. Esq. were elected hlembers. The following communications were read :-7 1. “On the Astringent SubsGnces ” (continued) by John Sten-house Ph. D. (See Memoirs Art. 34. T’ol. I.) 72. “ On fithogen and the &:thonitlee,” by IYilliam H. Bal-main Esq. On the Gch of December 184.2,I communicated to the Society the discovery of a new compound of nitrogen and boron which Mas named “Bthogen,” and which like cyanogen combined with the metals. At that time hopes were held out that I shou1tl be able to furnish the Society with an analysis of zthogen and the results of further experiments but I am still without tlie means of doing the former and have been prevented by illness from -c\.cjrl<ingmuch at the latter.Hoiyever wme experiments nhich 1 have been able to make have brought out very easy processcs for preparing zthogen and the ztbonides which niny be interesting to chemists and n-ill place at their disposal a ready mcanL; of obtaining these very StdJle compounds which niay prove powerful agents rKtliogen W;IS originally obtained by hcating together n mixture of boracic acid and melon and the principai dificulty ;ttteiidant upon the process was tlie previous preparation of the melon. ,411attempt having been made to form melon by heating together bicymide of mercury and sulphur it appeared that melon was formed but n-as with difficulty separated from the sulphuret of mercury which accmi-paxiied it ; but as the presence of tlx dpliuret cf rnercury (foes not interfere .cr.itli the formation of aethogcn froin a mixture of riielon and lioracic acid that substance may be obtained by siniply hent- ing together 5 parts of sulphur 38 of bicpiide of mercury and 7 of anhydroiij boracic acid or by heating togcther sulldiocyano- gen and boracic acid.Hwing an easy procws for lrepiuing xttio- gen it was advisable in the next place to hare a marc reid:,. inetliotf of forming the ztlionitles tlim that of lienting togethtr athogen ;trtd the metals which is a long and uncertain proccs.s au:i :ti1 atterq)t was made to form zthonides by heating rctliogeri with the sulpliuwts of the metals.As mic lit be expectcd from tlic st,!l)ility of atliogcii and its strong affinity for thc metals the xthogen ilil-c-ctiy displaced the sulpliur and forid the atthoriide. ITpmfurtlii-r cxperimel;~it was proved that the athonides might be nmic 11~-heating sulphur bicyanide uf mercury aiid boracic acid with the ~n~tallir: siilphurcts. The praportions should be such as would give riw tc tlic> presence of 2 atonis of the met;dlic sulphuret 2 atoms of bontcie itcid (sup-posing its conipo:itim to be BO,) 3 atonis of cyai~qen,ant1 3 ;ltoiuL of free sulphur. The zthoiiitles when thus formed iire not quite 1)iire hut may be readily purified by boiling with a !Gstu:e of nitric and rnurLitic acids ChP?,l.P?-oc.-No. T‘. 50 and afterwards washing carefully. In this way zthonides of sodium iron copper and lead have been formed. Common galena was need for the zethonide of lead ; and for that of iron,,iron filings and an ad-ditional quantity of sulphur. These four athonidss are all perfectly white and infusible ; before the blowpipe they yield the very beauti- ful phosphorescent light alluded to in a previous communication and in all respects resemble the aethonides of potassium zinc lead and silver whieh were described as being made by the other processes. In conclusion I beg to draw the attention of the Society to the remarkable stability of these compounds asd the very strong affii. ties of athogen. Bthogen attracts moisture from the air with great avidity and decomposes it so rapidly that a portion of aethogen which I have kept in a moderately well-stoppered bottle smells strongly of ammonia.The want of means must still be my apology for not furnishing the Society with a quantitative analysis but if any member of the Society will undertake one I shall be most happy to supply him with a fair specimen of aethogen. 73. ''On the Exhalation of Carbonic Acid from the Human Body," by E. A. Scharling Professor of Chemistry in the University and Polytechnic School of Copenhagen. Communicated by S. Elliott Hoskins M .D. With the view of ascertaining the quantity of carbonic acid ex-haled during the twenty-four hours as well from the lungs as from the general surface of the body Professor Scharling undertook the following experiments on six individuals viz.four males and two females. The subjects of experiment were confined in an air-tight box wherein they were perfectly at their ease being enabled to speak eat sleep or read without incoiivenience ; a constant current of at-mospheric air was admitted into the box and the deteriorated gases abstracted by means of an air-pump. The air withdrawn was con- ducted into a proper arrangement of bottles some containing sul- phuric acid others a solution of caustic potash. The quantity of carbonic acid both previous to and subsequent to each operation was carefully ascertained by being received into three graduated tubes. The results were as follows :-1st. The Professor himself aged thirty-five years exhaled 219 granimes" during twenty-four hours seven of which were spent in sleep.2nd. A soldier twenty-eight years of age exhaled 239,728 grammes = 5-45 oz. 3rd. A lad of sixteen 224.379 grammes =7-9 02. 4th. A young woman aged nineteen 165.347 grammes=5*S3 02. 5th. A boy nine years and a half old 133.126grammes =4-6902. 6th. A girl of ten 125.42 gramrnes =4-42 02. In the two last cases the period allotted to sleep was nine hours. From these experiments the Professor deduces that males exhale * =7-72 02. avoirdupois. 51 more carbonic acid than females and children comparatively more than adults. He also finds that less of this gas is given off during the night than during the day ; and that in certain cases of disease which he does not specify less carbonic acid is formed than during the healthy state.He is thence induced to hope that attention to this point may ultimately throw some light on certain forms of disease. it will be interesting to compare these results with Liebig’s views as well as with the experiments which have recently emanated from the French Acaddmie des Sciences. March 21 .-The President in the Chair. Twenty-four specimens of rare chemical products were presented for the Society’s Museum by Professor Liebig. Col. Yorke ex-hibited a specimen of magnesium obtained by voltaic action on the chloride of magnesium. The following papers were read :-74. ‘‘ On Theiiie,” by John Stenhouse Ph. D. (See Memoirs Art. 35.Vol. I.) 75. “ Observations on M. Reiset’s Remarks on the New Method for the Estimation of Nitrogen in Organic Compounds and also on the supposed part which the Nitrogen of the Atmosphere plays in the Formation of Ammonia,,’ by Heinrich Will Ph. D. (See Memoirs Art. 33. Vol. I.) March 30.-Anniversary Meeting the Presideiit in the Chair. ‘fie following Report of the Council was read by the President and subsequently ordered for publication :-Report of the C~uiaCilmade to the Chemical Society of Londoii March 30 1843. THEcompletion of a second year of the Society’s existence in cir- cumstances of increasing prosperity enables the Coiincil to congra- tulate their fellow-members on the positive attainment o€ the prin- cipal objects for which they are associated.The Society continues to be augmented in numbers and influence by the election of new Members and has been well supported by contribntions of original papers read at its meetings. The papers presented appear to in- crease both in number and value ; and any apprehension of a want of papers which formerly existed has been in a great measure dis- pelled by the experience of the last Session. It is now sufficiently evident that ample materials exist in England for il Chemical So-ciety and you have furnished unquestionable proofs of the utility of 52 such a Society in its power to advance the cultivation of chemical resesrch in the cguntry. ?‘liirtj-two Members have been elected into the Society since the last Anniversary.Our present numbers are-7 7 Members resident in London 57 Members resident in the country or ‘‘non-resident ” Members 10 Associates and 3 Foreign Members making a total of 147 Members with an annual income of 55211. The Society has thus early in its career to deplore the loss by death of two iMembers. HENRY Eeq. F.R.S.,who took an active part in the esta- HENXRLL blishment of the Society and was a member of the Council first elected. hh. Hennell will ever hold an honourable place in the history of chemistry as the discoverer of sulphovinic acid one of the earliest achievements in organic chemistry and which has since formed the starting-point for numerous important inquiries. Mr. Hennell was destroyed by a lamentable accideiit which no intelli- gence could have foreseen in tlie discharge of his professional duties as Chemical Operator to the Apothecaries’ Hall in the 45th year of his age.The shock of this deplorable event still unfits us from calmly estimating the scientific merits and highly amiable character of our lost friend. And Mr. HENRY INGLIS,of Kincaid Print Works near Glasgow who besides cultivating successfully the chemistry of calico-printing was distinguished for his accurate knowledge of the general science in the progress of which he took much interest. Mr. Inglis whose constitution was always delicate did not outlive his 43rd year. At the conclusion of last Session the Couiicil made a new arrange- ment with the Society of Arts for the use of two rooms for their meetings and a place of deposit for the property of the Society.These arrangements they have reason to helieve have given general satisfaction to the Members. The Society published the ‘rhird Part of its Proceedings and Memoirs in August last and has another Part at present passing through the press the great extent of which bas occasioned some delay in its publication. There have been received since last Re- port 41 communications from 21 contributors of which 20 are printed entire in the 3rd and 4th Parts and full abstracts given in the Proceedings of the remaining 2 1. These communications are the fruit of numerous and varied inquiries and form in the opinion of the Council a contribution of some importance to the progress of the science. The Council would refer in particular to the full ex- amination and discussion which the process of hlM.Will and Var- rentrapp for the detcrmination of nitrogen has received by the ex- periments of Mr. Francis and Dr. Fownes and more lately in Dr. Will’s own comprehensive memoir ;-to the series of useful papers on astringent substances which they owe to their valuable con- tributor Dr. Stenhouse ; and to the papers on various subjects con- nected with the metals and the salts by Professors Liebig and Gre- gory RIesers. Porrett Croft Cock Ralmain and Warington and on organic substances by Professors Liebig Johnston Everitt Dra. 53 Playfair and Fownes ; on agricultural subjects by Dr. Schweitzer and Mr. Chatterly ; on voltaic electricity by Mr.Arrott and on the heat disengaged in combinations by the President. The Council still presses upon these and other contributors not to relax their ex- ertions and invites the Members generally to communicate the re- sults of their inquiries. The Society has also received presents of interesting chemical products and crystalline specimens for their collection from various donors particularly Mr. Warington and Professor Liebig. They have also received several chemical works from their respective authors. The Council call attention to this nucleus of a collection which has been formed and which they hope will be rapidly in- creased by the exertions and liberality of the Members. The Council has also lately made arrangements for procuring the leading chemical Journals and circulating them among the Members.The condition of the Society’s finances is highly favourable as will appear from the following audited report of the Treasurer. Auditors’ Report. We have examined the accounts of the Chemical Society of Lon-don presented by Arthur Aikin Esq. as Treasurer and find the monies received to amount to- $2 8. d. For Subscriptions ...................... 161 0 0 Balance of former Audit ................ 146 16 8 307 16 8 And the Expenditure (for which vouchers have beenshown) ........................ 38 1 5 Balance in favour of the Society. ..... 269 15 3 With the Bankers Messrs. Coutts and Co... 263 17 3 In the hands of the Treasurer ............ 5 18 0 6269 15 3 WM.HAELEDINE PEPYS J.P. GASSIOT. London March 23rd 1843. The following gentlemen were elected as Officers and Council for the ensuing year :-President.-Arthur Aikin Esy.,F.L.S. F.G.S. Vice-Presidents.-William Thomas Brande Esq. ; John Thomas Cooper Esq. ;Thomas Graham Esq. ; Richard Phillips Esq. Treasurer.-Robert Porrett Esq. Secretaries.-Robert Warington Esq. and George Fownes Ph. D. Foreign Secretary .-E. F. Teschemacher Esq. Council.-Dr. Charles Daubeny ; Thomas Everitt Esq. ; Michael Faraday D.C.L. ; ,J. P. Gassiot Esq. ; Dr. William Gregory ; Per- 54 cival N. Johnson Esq.; James I?. My.Johnston Esq. ; Dr. W. B. Leeson ; W. Hallows Miller Esq. ; W.Hasledine Pepys Esq. ; Dr. G. 0. €tees ; Lieut.-Col. Philip Yorke. The thanks of the Society were given to the Officers and Council for their exertions during the past year.April 4.-The President Arthur Aikin Esq. in the Chair. “ The Guide to the Urinary Cabinet,” by R,Venables was pre-sented by Mr. George Knight Jun. Messrs. Knight and Sons exhibited their Urinary Cabinet. Professor Graham exhibited Dr. Mohr’s subliming apparatus as improved by Dr. Stenhouse. Mr. Garrod exhibited several fine specimens of Theine Caffeine and Theobromine. Edward Beaumont Pitchford Eeq. and John H. Pepper Esq. were elected Members. The following communications were then read ;-76. ‘<On the Subsulphates of Copper,” by J. Denham Smith Esq. (See Memoirs Art. 36. Vol. I.) 77. On the Spontaneous Decomposition of the Chlorate of Am- 8‘ monia,” by Mr.Joseph Wonfor. Having occasion lately to prepare a quantity of this salt the phae- nomena which form the subject of this communication were ob-served. The salt was prepared by adding to a saturated boiling solution of bitartrate of ammonia a saturated boiling solution of chlornte of potassa the liquor being strained from the precipitated cream of tartar and cooled as rapidly as possible it being observed that the ammoniacal salt underwent a change if allowed to remain at a high temperature for any length of time; the solution was then care-fully evaporated at a temperature below 100’ Fahr. and again strained from a small portion of cream of tartar which separated as the liquor was concentrated. The chlorate of ammonia ciystallizes in small acicular crystals or in plates similar to the chlorate of PO-tassa.The crystals are very soluble both in water and alcohol and have a sharp cooling taste. This salt was partially examined by Vauquelin but he does not appear to have observed the change it undergoes at the ordinary temperature of the atmosphere which most likely arose from his using the salt immediately after it was prepared. In Murray’s ‘ Elements of Chemistry,’ vol. ii. p. 544 it is stated that Vauquelin examined this salt the author remarks “ it crystal-lizes in fine needles and appears to be volatile as there is a consider- able loss on evaporating its solution ; its taste is extremely sharp ; it detonates when placed on a hot body with a red flame ; decomposed by heat it gives out chlorine gas with nitrogen and a little nitrous oxide hydrochlorate of ammonia with hydrochloric acid remaining.” Brande states in his Elements,’ on the authority of Vauquelin 55 ‘I (Ann.de Chim. xcv. 97) that this salt probably consists of one proportional of each of its components or 17 of ammonia + 76 of chloric acid ; but its composition has not been experimentally de- termined.” I have analysed the salt by decomposing it with caustic potash collecting the ammonia in water acidulated with hydrochloric acid and evaporating the solution carefully to dry- ness ; the chloric acid W~EIdetermined by igniting the salt after the action of potash in a porcelain capsule ; then calculating the amount by the weight of the resulting chloride of potassium my results gave one equivalent of ammonia one of chloric acid and one of water.After the salt had been prepared a few days the colour was ob-served to have changed from white to lemon-yellow and gave out an odour which powerfully affected the nose when held over the un- corked bottle irritating the eyes much more than chlorine and cau- sing a flow of tears ; this odour was dissimilar to that of any of the oxides of chlorine. The salt was put away till an opportunity should offer of examining the cause of this change. On going into the laboratory some days after the alteration in the appearance of the salt had been observed the bottle which contained about 4 ounces was found broken into innumerable particles and the remains of its contents strewed about the floor; on inquiry I was informed that during my absence it bad exploded with a loud report.Imagining the explosion was produced by the bottle being closely stoppered an ounce of the salt was introduced into a very strong phial and con- nected with a vessel containing a solution of nitrate of silver through which the products of the decomposition had to pass the unab- sorbed gases being collected in a jar at the pneumatic trough hoping to collect the gases as they were liberated. After gaseous matter had been quietly evolved for twelve hours it exploded with greater violence than before no portion of the bottle remaining (except the neck) larger than a pea. A quantity of chloride of silver had pre- cipitated from the nitrate and the gas jar contained free nitrogen.Another portion of the salt was then placed on a sand-bath the temperature of which was about 120° Fahr. ; this soon underwent decomposition but only detonated slightly giving off dense white fumes with the smell of nitrous acid. Finding the salt was so easily decomposed I proceeded to ex- amine more closely the nature of the changes that took place. 20 grains of the salt were introduced into a strong flask connected as in the previous experiment with a vessel containing solution of ni- trate of silver but with the mercurial instead of the pneumatic trough ; the flask was then very carefully warmed by a spirit-lamp ; the salt instantly exploded with great violence and a loud detonation breaking the flask to atoms.Five grains of the salt were then ope- rated upon without the vessel containing the solution of the silver salt and the products of the decomposition collected over mercury ; they were nitrogen chlorine nitrous acid and water with a little chloride of ammonium; but from the rapidity with which the gases were eliminated it was impossible to collect the whole of the pro-ducts of the decomposition though the experiments were repeated 56 six or seven times both with and without the vessel containing the solution of nitrate of silver. When five grains of the salt were em- ployed the tubes (which were filled with mercury when no salt of silver was used) were not broken ; still the action was so energetic that it did not allow of accurate indications of the quantity of the gases evalved being obtained.From the presence of free nitrogen and chlorine both in the pro- ducts of the spontaneous and produced decomposition I am led to conclude that chloride of nitrogen is formed; but as the whole of the products were in no case obtained it was impossible to deter- mine this experimentally. April 18.-The President in the Chair. The ‘‘American Journal of Science for 1S43,” presented from the Editors. *‘ A Description of a new Carbon Voltaic Battery,” by B. Silli-man Jun. Esq. A.M. from the Author. Mr. Bullock exhibited some scarce cliemical products. Dr. Heinrich Will of Giessen was elected a Foreign Member. S. Elliott Hoskins M.D. and William Brotlripp Itandall Esq. were elected Members.The following papers were then read :-78. “ On the Spontaneous Change of Fats,” by W. Beetz. (See Memoirs Art. 37. Vol. I.) ’79. “On certain Improvements in the Instrument invented by the late Dr. Wollaston for ascertaining the Rcfracting Indices of Bodies,” by John Thomas Cooper Esq. (See Alemoirs Art. 38. VOl. I.) May 2.-?Vm. ‘rhos. Brande Esq. F.R.S. Vice-President in the Chair. Mr. Bullock presented a specimen of iodine and hlr. TbTilrreKlDe la Rue one of the ferriclcyanide of iron to the Socicty’s Museum. Thomas Burrows Esq. was elected a hlemher and Mr. ,Joseph Wonfor an Associate Member of the Society. Tlic following communications were then read :-SO. “ Some additional Remarks on Theine,” by Joh Stenhouse Ph.I). (See Memoirs Art. 39. 1701. I.) 81. “ Note on the Preparation of rEther,” by Gcorge Fownes Ph. I>. The beautiful experiments of Rlitscherlich on tLe indefinite con- version of alcohol into zther by the same qumtity of bulphuric acid seem to point out the possibility of effecting 11 great iniprovenicnt in the ccoiiomical production of that important substance. It is well known that in the old process in which equal weights of arid and spirit are subjected to distillation a large quantity of alcol~ol 57 escapes stherification at the commencement of the process owing to the low boiling-point of the mixture and on the other hand much is destroyed towards the end of the distillation by the excess- ive heat ; the limits of temperature within which aether is generated in quantity being as is well known rather narrow ranging perhaps between 280' and 320'.In the continuous operation described by Mitscherlich such a mix-ture of alcohol and sulphuric acid is made that its boiling-point shall be well within the &her-producing limit while into this mixture maintained in a state of rapid ebullition alcohol is suffered to flow in such proportion as exactly to replace the liquid which distils over and which liquid is seen to consist of a mechanical mixture of aether and water with a very small quantity of unaltered alcohol. So long as the temperature is properly maintained by due regulation of the fire and the flow of alcohol the distilled products do not vary and the process itself may be it is said continued until the oil of vitriol becomes gradually destroyed by the impurities of the spirit or lost by volatilization.In this experiment absolute alcohol is used ; in the practical manu- facture of aether however this is obviously impossible ; it occurred to me therefore to try experimentally how far the process might be carried if ordinary rectified spirit were substituted. It is stated in- deed by Liebig that under such circumstances Etherification is put a stop to by the accumulation of the water introduced with the ale coho] gradually depressing the boiling-point of the mixture below the temperature at which Ether is formed and that this happens when the whole quantity of spirit used amounts to four times the weight of the oil of vitriol (Annalen der Pharmacie xxx.136). It is difficult to see how this could happen if attention were paid to the temperature of the boiling liquid since it would seem easy to regulate the point of ebullition so as always to maintain the acid of the same degree of concentration with respect to water. A niixture was made of 6 02. by weight of concentrated sulphuric acid and 32 02. by weight of rectified spirit of sp. gr. -836 at 60°. This mixture was introduced into a wide-necked flask fitted with a cork pierced with three holes for the purpose of receiving a thermo- meter a narrow tube connected with a reservoir of alcohol of the same density as that mentioned above and a wide tube for convey- ing the vapours to the condenser which was a common metal worm immersed in cold water.These arrangements being completed an Argand gas-lamp was placed beneath the flask and the contents made to boil; the thermometer speedily rose to near 300' F. A slender stream of spirit was now allowed to mix with the boiling liquid in such quantity as to maintain at once an invariable tem- perature and rapid and violent ebullition. It was soon found that by a little management the thermometer could be kept quite sta- tionary at any required point within the limits before referred to. At 300° and thence to 360° the separation of the distilled products into two strata was very distinct and beautiful ; at 280' to 290° enough alcohol passed over unchanged to prevent this separation Chem. Proc.-No. IT 58 until a little water had been added.There was a slight trace of sulphurous acid and the mixture in the flask gradually deepened in colour until at last it became nearly black without however in the slightest degree losing its efficiency. At this period the process had been kept up about fifteen hours ; more than a gallon of alcohol-twenty times the weight of the acid- had passed through the apparatus and as the activity of the opera- tion remained to the last unimpaired it seems fair to infer that its only limits are the loss of sulphuric acid by volatilization and the formation in small quantities of secondary products such as oil of wine sulphurous acid and olefiant gas. * The rether obtained was mixed with some caustic potash and rec- tified by the heat of warm water; its sp.gr. at 60' was 0730,and it measured fully three pints. As merely water at 55O was used for condensation in place of ice much loss of vapour must have oc- curred ; and since the residual alkaline liquid yielded a large quan-tity of alcohol by distillation the process must be considered on the whole a tolerably productive one although still vei-y far from what might be. desired. Of cour~e,on a large scale much of this loss would be avoided. It was remarked that during the whole of the operation even when the temperature was purposely kept so low as to allow much alcohol to escape decomposition a considerable quantity of perma- nent gas made its appearance. By adapting to the lower end of the worm of the condenser a two-necked receiver furnished with a bent tube dipping under water it was easy to collect and examine this gaseous matter.When purified from Ether-vapour by washing with oil of vitriol it was inflammable burned with much light and pos-sessed the peculiar alliaceous odour characteristic of purified olefiant gas. Its production became much increased by a rise of tempera- ture ; at 310' it passed in a rapid succession of large bubbles. There appears no difficulty then in applying Mitscherlich's con- tinuous process to the economical manufacture of Ether on the great scale ; it is very probable too that by avoiding the use of a naked fire much of the secondary action to which allusion has been made might be prevented while by a proper condensing arrangement the waste obvious in my own experiments would be avoided.The most advantageous temperature could be determined by experience in a very short time and with this knowledge the process might be con- ducted ever afterwards in such a manner as to yield a perfectly uni- form product. A somewhat low temperature about 280' to 290° might possibly be the most advantageous since it would be better to let a little alcohol escape aetherification than to use heat enough to occasion the abundant production of oil of wine and olefiant gas. This alcohol is easily recovered after the rectification of the Ether. It may be proper to mention also that the mixture in the distillatory vessel may be repeatedly suffered to cool and again reheated with- out injury.59 May 16.-The President in the Chair. Mr. Warington presented a specimen of the sulphate of chromium and potash (chrome alum) in large crystals to the Society’s Mu- seum. “ On the Heat of Chlorine Bromine and Iodine developed during the formation of the Metallic Compounds,” by Thomas Andrews M.D. from the Author. The Council submitted to the Meeting a resolution that the So-ciety should hold its sittings on the 1st and 3rd Mondays in the month instead of the Tuesday that evening being found to inter- fere with the meetings of the Linnean Society and the Society of Civil Engineers. Moved by Richard Taylor Esq. and seconded by J. Denham Smith Esq. that such resolution be adopted. John Gardner M.D. was elected a Member of the Society and Mr.John Carty an Associate. Mr. Francis exhibited and explained the method of taking the fusing point of fatty bodies as practised in the Giessen laboratory. The following papers were then read :-82. “ On Ferric Acid,” by J. Denham Smith Esq. (See Memoirs Art. 40.Vol. I.) 83. “ On the Action of Alkalies on Wax,” by R. Warington and Wm. Francis Esqrs. (See Memoirs Art. 41. Vol. I.) 84. ‘‘ On the Action of Suhhuric Acid on the Ferrocvanide of Potassium,” by George Fowne’s Ph. D. (See Memoirs -Art. 42. VOl. 1.) The’Society adjourned to the Evening of the 1st Tuesday in November. INDEX ‘1‘0THE PROCEEDINGS. VOI,. I. AcrDs :-products of the action of ni-tric on castor oil 5 ; preparation of hydrochloric 7 ; malic 12 ; .chro-mic 17 ; conversion of benzoic into hippuric 22,33 ;pyrogallic 41,43 ; preparation of malic from culinary rhubarb 47 ;exhalation of carbonic from the human body 50; ferric -59 ; action of sulphuric on the fer- rocyanide of potassium 59.Aither oxalic Inethylic decomposition of by alcohol 19 ; preparation of 56. Zthogen 44,49. Ethonides 4.1 49. Air analysis of atmospheric 13. Alcohol decomposition of oxalic me- thylic =ether by 19. Alkalies action of on wax 59. Ammonia supposed part which the ni- trogen of the atmosphere plays in the formation of 51 ; chlorate of spontaneous decomposition of the 54. Anniversary report and address 26,5 1. Archil substances contained in the li- chens employed for the preparation of 21.Arragonite on a specimen of artifi- cial 9. Arrott (Alexander) on some new cases of galvanic action and on the construction of a battery without the use of oxidizable metals 43. .4ssafaetida oils of analysis of 15. Atomic weights revision and more exact determination of 15. Auditors’ Report 28 53. Balniain (W.H.) on zethogen and the r~tlionides 44 ; on tlie probable existence of nitrogen combined with silicon in soils and other substances 45 ; 011 rethogen and ,~jthonides 48. Beetz (W.)on the spoiitaneoiis changc of fits 56. Beiizoic acid conversion of into hip- puric acid in the animal economy 22. Brewing observations on 23. Bunsen (Prof.) on a new class of ca-codyl compounds containing plati- num 17 ; on the radical of the ca- codyl series of compounds 21.Cacodyl compounds new class of con- taining platinum 17. Cacodyl series of compounds radical of the 21. Cadmium salts of 36. Caloric agency of in permanently mo-difying the state of aggregation of the molecules of bodies 18. Carbon atomic weight of 9 11. Carbonic acid exhalation of from the human body 50. Castor oil products of the action of ni-tric acid on 5. Cetine analysis of 14. Chalk on hardening it by Prof Kuhl-man’s process for the silicification of limestones 11 ; analvsis of the of the Brighton cliffs 26. Cliatterly (hi. W. F.) on saline ma-nures containing nitrogen 41. Chlorate of ammonia spontaneous de- composition of the 54. Chromic acid preparation of I7 ; em-ployment of as a11 agent in galva-nic arrangements 18.Chromium and potash new oxalate of 23 ; additional observations on the red oxalate of 40. Clark (Dr.) his method of ascertain- ing the hardness of water 8; on the revision and more exact determina- tion of atomic weights 15; on a gas-burner for a laboratory table 35. Cock (W.J.) on the production of artificial uranite 38 ; on palladium its extraction and alloys 4G. Conprr (Johu T.) on improvements 62 INDEX. in the instrument invented by the late Dr. Wollaston for ascertaining the refracting indices of bodies 56. Copper and other ores combined with sulphur mode of treating 8 ; sub-sulphates of 54. Council and officers in 1841 2 ; in 1842 29 ; in 1843 53.Croft (Henry) on the decoinposition of oxalic inethylic Ether by alcohol 19; on a new oxalate of chromium and potash 23 ; on some salts of cadmium 36 ; on the manufacture of sugar from the Zea Mays 48. Cudbear substances contained in the lichens employed for the preparation of 21. De la Rue (Warren) on the agency of caloric in permanently modify- ing the state of aggregation of the molecules of bodies 18. Detmer (M.) on bleaching salts 5. Dumas (M.)on the analysis of at-mospheric air 13. Equivalents of the phosphorus family of elements division by three of the 44. Ethal analysis of 14. Eucalyptus on the sugar of the 47. Everitt (Thos.) on the preparation of malic acid from culinary rhubarb 45.Fat formation of in the animal body 46 ; spontaneous changes of 56. Ferric acid 59. Formation of the Society and list of original members 1. Fownes (George) on the preparation of artificial yeast 26 ; 011 the prepa- ration of hippuric acid 33 ; on two specimens of South Sea Guano 36 ; on the analysis of organic substances containing nitrogen 41 ; on the pre- paration of Ether 56 ; on the action of the sulphuric acid on the ferro- cyanide of potassium 59. Francis (W.) on the determination of nitrogen in orgnnic analysis 44 ; action of alkalies on wax 59. Garrod (A. Baring) on the conver-sion of benzoic acid into hippuric acid in the animal oeconomy 22. Galvanic action some new cases of 43. Graham (Prof.) on the preparation of clilorate of otash 5 ; on the con- stitution of t!e sulphates as illus-trated by late thermometrical re-searches 22 ; on heat of combina-tions 41 ; on the division by three of the equivalents of the phosphorus family of elements 44.Gregory (Dr. W.) on a simple and cheap method of preparing pure hy- drochloric acid and of any required strength 7; on a new method of obtaining pure silver in the metallic state or in the form of oxide 47. Guano on two specimens of South Sea 36. Hagen (R.) on malic acid and its salts 12. Heat specific and conducting power of building materials 24. Hippuric acid conversion of benzoic acid into in the animal economy preparation of 33. Hutchinson (John) on the specific heat and conducting power of build-ing materials 24.Hydrometer and saccharometer mode of reducing the indications of the to each other 16. Hyssop oils of analysis of 15. Ilex Paraguayensis separation of theine from the 48. Iron artificial magnetic oxide of 14. Jolinston (J. 1:. W.) on the sugar of the Eucalyptus 45. Kuhlnian (Prof.) on chalk hardened by his process for the silicification of limestones 11. Liebig (Prof.) on the preparation and formation of yellow pnissiate of potash 2 ; on the atomic weight of carbon 9; on the preparation of' cyanide of potassium and its appli- cations 24 ; on the formation of' fat in the animal body 46. Light flashes of observed during the crystallization of nitrate of stron- tian 5.Malic acid and its salts 12 ; prepara-tion of from ciilinary rhubarb 47. Manganese protosulphate of action of chromate of potash on the 30. Manures saline experiments with containing nitrogen 41. Marchand (Dr. R. F.) on the atomic weight of carbon 11. Maugham (Mr.) on the mode of treating copper ores and ores of other metals coinbiiied with sulphur to ascertain the quantity of sulphur INDEX. 63 in such ores and also the quantity of copper in the native sulphuret 8. Mellon formation of 5. Mercury change of colour in the biniodide of 23. Metals oxidizable construction of a battery without the use of 43. Milk formation of in the animal ceco- nomy 46. Miller (Prof. W. €I.) extract from a letter from 29.Nitric acid products of the action of on castor oil 5. Nitrogen analysis of organic sub- stances containing 41 ; cletermina-tioil of in organic analysis 44 ; on saliiie manures containing 44. probable existence of combined with silicon in soils and other substances 45 ; observation on hl. Reiset’s re- marks on the estimation of in or-ganic compounds 51. Officers and council in 1811 2; in 1842 29; in 1843,53. Palladium its extraction and alloys 4G. I’arnell (E. A.) on the forniation of niellon 5 ; 011 the influence of water in chemical reactions 15 ; on tlie equilibriuni of the temperature of bodies in contact 32. Piesse (Septimus) observations on brewing 23. Platinum new class of cacodyl com- poiuids containing 17.Playfair (Dr. Lyon) 011 the formation of milk in the animal Ceconomy 4G. Porrett (Robert) on a curious forma- tion of prussian blue 32. Potash yellow prussiate of prepara- tion and formation of 2 ; preparn-tion of the chlorate of 5; chro-mium new oxalate of 23; chro-mate of action of on the protosal- phate of aanganese 30 ; chro-mium additional observations on the red oxalate of 40. Potassium,. preparation of the cyanide of and its applications 24 ; action of the sulphuric on the ferrocyanide of 59. Prussiaii blue curious formation of 35 ; formation of upon the surface of gravel through tlie medium of ferrocyanide of calcium 47. I’yrogallic acid 41 ; astringent sub-staiices as sources of W. Pyroxjlic spirit on 12.Redtenbacher (Prof.) on the atomic weight of carbon 9. Reiset Observations on his reinarks on the estimation of nitrogen in organic compounds 51. Report Auditors’ 28 53. Saccharometer and hydrometer mode of reduciiig the indications of the to each other 16. Salts bleacliing 5 ; of malic acid 12. Scanlan (M.) on flashes of light ob- served during the crystallization of nitrate of strontian in the dark 5. Scharling (Prof. E. A.) on the ex-halation of carbonic acid from the human body SO. Schunck (Edward) on some of the sub- stances contained in the lichens em- ployed for the preparation of arcliil and cudbear 21. Schweitzer (Dr. E. G.) on the ana- lysis of the chalk of the Brighton cliffs 29. Silver new method of obtaining it pure in the metallic state or in the form of oxide 47.Sims (Olice) on phosphate of yttria 7. Smith (J. U.) on the subsulphates of copper? 54 ; on ferric acid 59. Stenhouse (Dr J.) on the analysis of cetine and ethal 14; on the ana- lysis of the oils of laurel turpentine hyssop and assafcetida 15 ; on py- rogallic acid 41; onsome astringent substances as sources of pyrogallic acid 43 ; on astringent substances 49 ; on theine 51 ; additional re-marks on theine 56. Strontiaii nitrate of appearance of flashes of light observed during the crystallization of 5. Sulphates constitution of the as illus-trated by !ate thermometrical re-searches 22. Sulphur mode of treating copper and other ores combined with a.Sulphuric acid action of on the ferro- cyanide of potassium 59. Theiiie 51 ;additional remarks on 56. Thomson (‘T’. S.) on the artificial mag- netic osidc of irori 14. Tilley (T. G.) on sonie of the pro-ducts of the action of nitric acid on castor oil 5. ‘Turpentine analysis of oils of laurel 15. 64 INDEX. Uranite production of artificial 38. Ure (Dr. Andrew) on pyroxylic spi-rit 12. Warington (R.)on the mode of re-ducing the indications of the sac- charometer and hydrometer to each other 16; on the pre laration of chromic acid 17; 011 the employ- ment of chromic acid as an agent in galvanic arrangements 18 ; 011 the change of colour in the biniodide of mercury 23 ; on the action of chro-mate of potash on the protosul hate of manganese 30; additiona! ob-servations on tlie red oxalate of chromitm and potash 40; on :he formation of prussian blue upon the surface of gravel through the me- dium of ferrocyanidc of'calcium 47 ; 011 the action of alkalies on wax 50.Water method of ascertaining the hardness of 8; influence of in che-mical reactions 1.5. Wax action of alkalies 011 59. Will (Dr.) on M. Reiset's remarks on the estimation of nitrogen inorganic compounds 44 51. W ollaston (Dr.) improvements in the instrument invented by the late for ascertaining the refracting indices of bodies 56. Wonfor (Joseph) on the spontaneous decoiiiposition of the chlorate of ammonia 54. Yeast artificial preparation of 26. Yorke (Col.) 011 a specimen of artifi-cial arregonite 9.Yttria phospbate of 7. Zea Map,manuftwture of sugar from the 48. Printed by Iiichord and .John E. Taylor Xed Lion Court ReeI Strect.