ON POTASSO-GYPSITE. XX1X.-On Chlorophosphuret of Nitrogen and its Products of Decomposition. PART11. BY J. H. GLADSTONE,PH.D. F.C.S. In my former Paper upon Chlorophosphuret of Nitrogen,* it was stated that the decomposition which the solutions of that substance in alcohol and ether spontaneously undergo would be reserved for after-consideration. I now return to that part of the inquiry. It was early observed that when the white mass produced by the action of ammoniacal gas on pentachloride of phosphorus was washed with ether to separate the chlorophosphuret of nitrogen and the solution suffered to evaporate other substances beside the crystalline body in question made their appearance. The chloro- phosphuret was coloured pink or red and smelt strongly of hydro- chloric acid; and upon the addition of water it was evident that some body possessing oily properties was also present; whilst the aqueous solution reacted very acid and upon evaporation after the hydrochloric acid had been driven off left a semi-crystalline mass * Chem.SOC. Qu. J. X. 135. VOL. 111s-NO. XII. AA 354 DR. GLADSTONE ON CHLOROPHOGPHURET OF NITROGEN very soluble in water but insoluble or nearly so in alcohol. This was powerfully acid to test-paper was capable of being neutralized by potash and a slightly acid solution gave flocculent white precipi- tates with nitrate of silver and chloride of calcium requiring conside- rable excess of nitric acid to redissolve them. In fact ether was found capable of effecting a gradual but com-plete transformation of chlorophosphuret of nitrogen into hydro- chloric acid the new acid just mentioned and a varying amount of yellowish liquid immiscible in water having an aromatic odour.If the ethereal solution be heated the change is immediately brought about the oily liquid being produced in such quantity as to render the solution turbid. The action of alcohol is equally destructive; but hydrochloric acid and the oily body are the sole products. If some crystals of chloro- phosphuret of nitrogen be placed in a small quantity of alcohol quite inadequate to dissolve them they will be found in a few days to have disappeared the oily body into which they have been trans- formed being taken up by the alcohol. DEUTAZOPHOSPHORIC ACID.The acid produced from chlorophosphuret of nitrogen under the influence of ether crystallizes in feathery crystals or groups of microscopic spiculz. That the substance is free from ammonia is evident from the fact that it does not yield that gas when boiled with baryta-water or weak potash; and as the neutralized solution gives no precipitate when mixed with a metallic salt it cannot con- tain either phosphoric or azophosphoric acid. The acid crystals dried in vucuo at the ordinary temperature do not lose in weight when heated to loooC ;but upon increasing the heat they fuse swell and evolve an ammoniacal salt containing phosphorus in some form and afterwards free ammonia. There remains azophosphoric acid (easily recognized by the immediate production in the cold of the characteristic iron-salt when mixed with a solution of the sulphate of that metal),’.together with some glacial phosphoric acid.Oxidizing agents have little action upon this crystalline acid nitric acid even may be boiled upon it long without causing decom- position. Strong sulphuric acid in the cold has likewise no effect beyond that of dissolving it As the crystals themselves were not very definite in appearance and as some which had been put aside for a few months were found to have undergone a spontaneous change with the formation of AND IT$ PRODUCTS OF DECOMPOSITION. ammoniacal salts it was feared that no good analytical results were likely to be obtained from the acid itself. Its insoluble salts how- ever promised better.Upon the addition of nitrate of baryta to a solution of the crystals a white flocculent salt is formed. This was analyzed; but such differences in the estimation of the base as 43and 60 per cent soon showed that no reliance was to be placed upon the uniformity of composition of this precipitate. One property of this crystalline acid is to produce azophosphoric acid when its solution is boiled with certain metallic salts. If the sulphate of the sesquioxide of iron be added to an aqueous solution of these crystals no precipitate appears proving that azo- phosphoric acid does not pre-exist in them; but it is instantly formed on boiling. Again if the acid be nearly neutralized by an alkali and boiled with a solution of most other metallic salts such as sulphate of copper the azophosphate of the metallic base gradually precipitates.Now this is precisely what occurs when an azophosphate is pro- duced as described in my former Paper. It was there directed that chlorophosphuret of nitrogen should be dissolved in alcohol and decomposed by ammonia; the salts thus obtained were then to be evaporated to dryness redissolved in water and boiled with the sulphate of iron or other metallic salt till the azophosphate was precipitated. It seems probable therefore that the alkali accom- plishes instantaneously the same decomposition which the chloro- phosphuret of nitrogen slowly undergoes when dissolved in ether ; and that the resulting salts are really the combinations of hydro-chloric acid and the new crystallizable acid with the alkali employed.And this supposition is confirmed by the fact that the neutral or slightly acid solution obtained by decomposing chlorophosphuret of nitrogen by an alkali does yield similar flocculent precipitates when niixed with solutions of baryta or lime salts; and if nitrate of silver be employed a precipitate is formed which is very readily acted upon by the light and mixed with a large quantity of chloride of silver. Baryta-suZt.-Various attempts were made to analyze the baryta- salt. Some peculiarities exhibited in its production must be noticed. If a strong solution of nitrate of baryta or chloride of barium be added to a slightly acid solution a precipitate falls; but a more copious precipitate is obtained from a neutral or slightly ammoniacal solution; yet the precipitate is itself wholly soluble in a considerable amount of ammonia and may be regained (perhaps in an altered condition) by evaporating off the large excess.The salt in question AA2 356 DR. GLADSTONE ON CHLOROPHOSPHURET OF NITROGEN is to some extent soluble in water but the presence or absence of different salts in the liquid appears greatly to affect its solubility. The results of analyses of different preparations of this baryta-salt are highly variable and I shall merely give the percentages without details. The base was of course always weighed as sulphate and thus there can be little doubt respecting the accuracy of its determi- nation; but although various means were resorted to €or the estima- tion of the phosphorus and nitrogen I never felt satisfied that the whole amount of either was obtained.The last four determinations recorded below form a series. Some chlorophosphuret was decornposed by means of alcohol and ammonia and evaporated to?dryness ; when redissolved it was slightly acid. A concentrated solution of chloride of barium was added which precipitated a white flocculent salt this furnished result No. 4. Ammonia added to the filtered solution caused a small precipitate which yielded No. 5. The solution separated from this was warmed and more ammonia was added a similar precipitate fell which was collected and the solution on standing yielded a fresh quantity of salt.These precipitates furnished respectively Nos. 6 and 7. The method adopted for analysis was first to heat the salt previously dried at loooC. in a tube per se and collect the water and am- monia evolved in a tube filled with sticks of potash and a Will’s h ydrochloric-acid apparatus annexed to it. The resulting mass was then dissolved in dilute acid and the baryta precipitated as sulpbate ; the solution containing then the free acid not already decomposed was nearly neutralized by carbonate of potash and was boiled with sulphate of sesquioxide of iron to convert as much as possible into the azophosphate. This was separated and the liquid evaporated down and fused with hydrate of potash. The gas evolved was collected and the phosphoric acid contained in the alkaline mass was estimated as usual.In No. 4.the salt was not heated per se. I. 11. 111. IV. v. VI. VII. Baryta 49.8 52.2 51.4 45.0 46 53.2 55.0 Phosphorus 10.8 14.0 19.0 15.9 -22.4 17.3 Nitrogen 1.1 -6.6 -5.0 5.4 I Hydrogen --1 0.7 0.8 The salt evidently varies in composition. There appeared no reason for believing that salts of other bases would be more uniform and the difficulty of obtaining a quantity of the chlorophosphuret of AND ITS PRODUCTS OF DECOBlPOSITION. nitrogen rendered me little disposed to undertake more analyses of so unpromising a character. If the formation of the acid in question be considered we can scarcely entertain a doubt as to its true composition. It is formed from chlorophosphuret of nitrogen by the action of alkalis; the alcohol which is necessary for the success of the process appears to play no other part than that of a solvent.The whole of the chlorine is removed as I have found by direct experiment ;but the phosphorus and nitrogen seem to give rise to no secondary products. NO phosphoric phosphorous or nitric acid is formed; nor have I been able to detect ammonia when potash has been the alkali employed; neither is there any gaseous body evolved. We can only imagine therefore that the chlorine of the chlorophosphuret is replaced by oxygen thus P,N,C15 + 5 KO = P,N,05 + 5 KC1. Again in the decomposition of chlorophosphuret of nitrogen by means of ether no other bodies appear to be formed except hydro- chloric acid and the acid in question the aromatic liquid of which a larger or smaller quantity is usually found accompanying the preparation being a secondary product unessential to the decom- position.This is consistent with the view just expressed but it supposes that the decomposition depends upon the water present in the organic solvent. In order to test this important point some crystals were dissolved in anhydrous ether and the solution kept in a well-stoppered bottle; it was then found that the chlorophosphuret remained unaltered even after the lapse of thirty days. Nor does a solution in anhydrous ether undergo any change upon boiling. The ether then has no specific action on chlorophosphuret of nitrogen beyond that of a solvent; it merely facilitates its coming into contact with water and the real decomposition would appear to be P,N,C1,+5HO=P,N20,+5HC1.Indeed the presence of ether is not absolutely essential; for if some perfectly purc crystals of the chlorophosphuret be allowed to remain in distilled water for several weeks the liquid will be found to react distinctly acid and to be in reality a solution of the two acid products of decomposition given in the formula above. Again this acid or its compounds boiled with certain metallic salts yield the allied body-agophosphoric acid-having the formula Y,NO,. Now if this last arise from P,N,O, it will simply be by the elimination of 1 atom of phosphorus and 1 atom of nitrogen most probably as phoraphite of ammonia by the fixation of the ele- 358 DR.GLADSTONE ON CHLOROPHOSPHURET OF NITROGEN. nients of water. That ammonia is really one of the products of the decomposition I have repeatedly satisfied myself; but I have never succeeded in obtaining clear indications of phosphorous acid ; yet when it is remembered that heat is always employed and that metallic salts are present it is scarcely to be wondered at that so oxidizable a substance should be converted into phosphoric acid; and that is always found. Yet in order to have numerical proof that this new acid really did contain phosphorus and nitrogen in the proportions here assigned to it the last-mentioned reaction was taken advantage of. Some crys- tals formed by the spontaneous evaporation of an ethereal solution of chlorophosphuret of nitrogen and purified by washing with alcohol were dried in vacuo over sulphuric acid.They were then dissolved in water and sulphate of the sesquioxide of iron was added; on boil- ing azophosphate of iron separated which was collected and dried in vacuo. The filtered solution was gently evaporated to dryness and the resulting salt was fused with hydrate of potash in a silver tube and the evolved ammonia and resulting phosphoric acid were estimated as described in previous experiments. 0.219 grm. of the crystallized acid yielded 0.217 grm. of azophosphate of iron (Fez0, P NO, 5 HO) and afterwards 0.1205 grm. of ammonio-chloride of platinum and 0.0655 grm. of phosphoric acid which is As azophosphate. Not as azophosphate. Phosphorus . 0.0571 0.0291 Nitrogen .. 0*0125 OwO078 It appears then that two-thirds of the phosphorus is removed in the form of azophosphate of iron while the remaining one-third combines with oxygen. There is certainly not as much nitrogen found in the form of ammonia as in the azophosphate; but when it is borne in mind that the whole of the ammonia is never obtained by the process followed I conceive the experiment lends its full weight of evidence to the view given above of the formation of azophos-phoric acid. A second portion of acid was likewise analyzed by boiling with iron-salt and subsequent fusion with potash. 0.463 grm. of the crystals dried in uacuo yielded 0*414grm. of azophosphate of iron 0.440 grm. of ammonio-chloride of platinum and 0.148 grm.of phosphoric acid. If the whole amounts found of the two elements-phosphorus and nitrogen-be reckoned to 100 parts we have AND ITS PRODUCTS OF IDECOMPOSITION~ I. 11. Phosphorus . . . 39-36 $8.01 Nitrogen . . . . 9.27 ll*OS which indicates at least 8 atoms of water. Reasons will presently be assigned for believing this acid to be tribasic. The formula 3 "0,P3N 0,,5 HO would require Phosphorus . 96 40.67 Nitrogen . . . . 28 11-86 . 40 16.95 Oxygen . Water . . . . 72 30-51 -. 236 100~00 This view of the constitution of the acid itself simplifies our cou-ception of the reaction by which azophosphoric acid is produced It will be 23 HO. P,Nz05. 5 HO + 3 (MO,SO,) + S HO = 3 MO. P NO,. 5 HO + PO + NH + 8 SO, As this crystalline acid is analogous to azophosphoric acid but differs from it in the same manner as the latter differs from phos- phoric acid namely by the addition of PN I shall designate it-Deut-azophosphoric Acid.Deutaxophosphate of baryta-This salt has been already described it varies in composition. In the experiment which afforded the series of analyses Nos 4 to 7 the base increased in amount and even- tually a salt was obtained having very nearly the composition 3 BaO P,N,O, 3 HO. Calculated. Found. VI. VIL Baryta . 230 5463 53.2 55.0 Phosphorus . 96 22.80 22.4 17.0 Nitrogen. 28 6.65 5*O 5*4 Hydrogen 3 0.71 0.7-0-8 I) Oxygen . 64 15*20 421 100*00 This baryta-salt like the azophosphate is decomposed by heat turning black and evolving at the same time aqueous vapour ammonia and free oxygen which has arisen from the decomposition of water to supply the hydrogen which has entered into combination 360 DR.ULADSTONE ON CHLOROPHOSPHURET OF NITROGEN with part of the nitrogen. Thus in the two analyses just recorded the loss in weight caused by heating the salt coincided very nearly with that which was calculated from the amounts of ammonia and water given off Decomposed Theoretical Actual Water. Nitrogen. water. loss. loss. Exp. VI. 0.0065 -+ 0.0045+ 0.001 x 9 = 0020 0.023 Exp. VII. 0.0055 + 0*0033+ 0*0007x 9 = 0.015 0.015 Deutazophosphate of Ammonia.-In the decomposition of chloro- phosphuret of nitrogen by an alcoholic solution of ammonia we obtain this salt mixed with chloride of ammonium.Now the amount of chloride of ammonium produced from a known weight of the chlorophosphuret can be easily calculated. If therefore we sub-tract the amount of it from the weight of the dry salts we obtain the weight of the deutazophosphate which has been formed. During the investigation of azophosphoric acid the decomposition of the original chlorophosphuret of nitrogen was thrice performed quantitatively. Excess of ammonia was employed and the resulting salts were dried in a water-bath. Exp. I. 0.2135 grm. of P N C1 yielded 0.387 grm. of ammo-niacal salts. Exp. 11. 0.2553 J J 0.469 9 J J9 Exp. 111. 0.7035 > 1.2505 , JY Now 0.2135 grm. of P N C1 consists of 0*088 P3N, and 0.11255 C1 which would produce 0.1895 NH C1; and this number sub- tracted from 0.387 leaves 0.1975 as the amount of deutazophos- phate of ammonia.Therefore Exp. I. 0.088 grm. of P3 N yields 0.1975 grm of am- monia-salt. Similarly Exp. 11. 0.105 , 9 0.2425 , , and Exp. 111. 0.2894 , ,> 0.6264 , , These numbers are in the ratio of- Exp. I. Exp. 11. Exp. 111. 100 100 100 224.4 230.9 216.4 So large an increase of weight tends to show that at least three equivalents of oxide of ammonium have combined with the deutazo- phosphoric acid. A formula deduced from such slight grounds is of 361 AND ITS PRODUCTS OF DECOMPOSITION. course problematical and the variations in the three results (mainly attributable to the very deliquescent character of the salt) are beyond the range of a single equivalent of water; yet if we suppose the ammonia-salt to have a composition similar to that of the baryta- salt namely 3 NH 0.P3 N 0,. 3 HO the increase upon the original P3 N would be as- 100 216.9 a number coincident with the lowest and most trustworthy result afforded by experiment. If ammonia be added to a strong solution of the pure acid a mass of crystals immediately separates; upon the application of heat this crystalline precipitate redissolves and there remains a neutral salt which may be evaporated to a syrup without crystallizing. If this neutral substance be dissolved in a small quantity of water the addition of strong ammonia will again cause the precipitation of a crystalline salt.Deutazophosphate of ammonia is very deliquescent in damp air ;when heated per.se it swells up greatly and evolves am- moniacal gas whilst azophosphoric acid is found among the products in the fixed residue. Deutazophosphate of Silver.-A portion of the flocculent diffi- cultly soluble silver-salt rneutioned at the commencement of this paper was found to contain only 53.2 per cent of oxide of silver,- which is much less than a composition similar to that of the baryta- salt would require. Deutazophosphoric acid is capable of forming white flocculent salts with the earths,-baryta strontia lime and magnesia and with oxide of lead; but I have not succeeded in preparing salts of this acid containing such metals as iron copper or zinc either by double decomposition or by presenting the freshly precipitated oxide to a solution of the acid itself.AMMONIO-AZOPHOSPHATE OF IRON. An examination of this substance was nndertaken principally in the hope that it would throw some light upon the function of those atoms of water which form a constituent of the azophosphates and deutazophosphates and which cannot be driven off at least from the former without destroying the salt itself. It was stated in my previous paper that azophosphate of iron is wholly soluble in ammonia but that the compound thus formed is decomposed on evaporation in a water-bath. If however the drying be conducted at the ordinary temperature in vacuo over SUL 362 DR. GLADSTONE ON CHLOROPHOSPHURET OF NITROGEN phuric acid a deep-red mass is obtained covering the bottom of the vessel like a varnish and splitting up as it becomes perfectly de- siccated.This substance dissolves completely in cold water giving a red solution neutral to test-paper. 0.2253 grm. of this substance dried in vacuo decomposed by dilute hydrochloric acid yielded 0.1645 grm of azophosphate of iron (Fe 0,. P NO,. 5HO) and 0.120 grm. of chloride of ammonium. Now 0.120 grm. of chloride of ammonium is equivalent to 0.0583 grm of oxide of ammonium and such an amount it is which must be added to the 0.1645 grm. of azophosphate in order to approximate the original weight of the salt 0.2253 grm. 0.1645+0*0583=0*2228. Or if these numbers be reckoned to 100 parts we have 73.0 Azophosphate of iron Fe 0,.P NO,. 5HO . Oxide of ammonium NH 0 . . . 25.8 -98.8 This agrees most nearly with the numbers deduced from the formula Fe 0,. 3NH4 0. P NO,. 6HO. namely Azophosphate of iron . 243 75.70 Oxide of ammonium . . 78 24-30 7- 321 100*00 This experiment appears to indicate that the 5 atoms of combined water are not either wholly or partially basic but are nevertheless intimately connected with the compound itself yet as 1atom can be driven off from the iron-salt by heat and as the azophosphate of baryta contains but 2 atoms of water the hydrogen cannot be con- sidered as an integral part of the formula of the acid. Applying the phosphoric-acid theory of Messrs. Fleitmann and Henneberg to the expression of the azophosphate of iron we shall have the formulae 2Fe 03+2(P NO,.5HO) and 1+P NO,. 5HO. Fe2 3NH 0 j '3 AROMATIC LIQUID. It has already been stated that chlorophosphuret of nitrogen is decomposed under the influence of alcohol giving rise to hydro- AND ITS PRODUCTS OF DECOMPOSITION. chloric acid and a liquid body having an aromatic odour and not miscible with water. This last substance is readily soluble in alcohol and in the essential oils. It has usually a slight yellow tinge but I have obtained it nearly colourless. It appears incapable of being distilled without change. A portion subjected to a temperature gradually increasing was decomposed at a little above 100° C.; a light colourless and highly volatile liquid came over ;and afterwards a heavy oleaginous body of a very pungent odour which was not miscible with the former.The aromatic liquid in question is not attacked by aqueous solutions of potash nitric acid or sulphuric acid; but it is instantly decomposed by an alcoholic solution of potash with the formation of salts which are perfectly soluble in water and which when fused with an excess of the alkali yield ammoniacal gas whilst phosphoric acid remains in the fixed residue. The solution of the salts obtained by this decomposition of the liquid by means of any alkali when properly neutralized affords a baryta-salt resembling the deutazophosphate of baryta just described ;if mixed with a solution of sulphate of sesquioxide of iron it gives no precipi-tate at first; but on boiling it yields the characteristic white flocculi of azophosphate of iron The aromatic liquid then contains deutazophosphoric acid.A portion of the liquid under examination was purified from ad-hering acid and water first by carbonate of soda and afterwards by standing over dry chloride of calcium. It was-then introduced into a small glass bulb and burnt with chromate of lead as in the usual combustion-process for organic compounds. In consequence of the liquid becoming carbonized in the bulb the combustion was worthless as a quantitative experiment; but it proved that the substance con- tained a large percentage of carbon and hydrogen; and if the mode of its formation be considered I think there can be little doubt that the aromatic liquid iu question is deutazophosphoricether.From the reactions which have formed the subject of this paper it appears that the so-called “chlorophosphuret of nitrogen” is a body analogous in constitution to pentachloride of phosphorus. It exhibits little or no tendency to combine with any other substance without itself undergoing decomposition; but it is resolved by as- sumption of the elements of water into hydrochloric acid and another acid-a compound of the electro-positive portion with five equivalentg of oxygen. PC15+5HO=P0,+SHCI and P N C1 =t 5 HO =P N O,+5HCl. 363 DR. GLADSTONE ON CHLOROPHOSPHURET OF NTTROGEN The reaction by which it is formed when ammonia and penta- chloride of phosphorus are brought together cannot be distinctly traced.It is evidently a by-product-a result in all probability of the action of the newly-formed compounds of phosphorus and nitrogen upon the pentachloride. It is not found amongst the pro- ducts of decomposition when pentabromide of phosphorus is heated with chloride of ammonium. It was to be expected that a substance might exist presenting a composition intermediate between that of pentachloride of phos-phorus PCI, and chlorophosphuret of nitrogen P N CI,-in fact P NCI,--and which should give azophosphoric acid Pz NO, when decomposed by water ;but no such compound has yet been observed. Liebig and Wohler mention a substance given off in the prepa- ration of chlorophosphuret of nitrogen which has a peculiar and distinct odour I have remarked the same but only I believe when the chloride of phosphorus has not been thoroughly saturated with chlorine.The two acids with which this investigation has made us ac-quainted may be considered as the second and third terms of a series commencing with ordinary phosphoric acid and bearing a marked resemblance to it both in their tribasic character and in their general properties. They differ in composition from phosphoric acid in containing its elements PO conjugated with PN or 2PN; and thus present another instance of that law of which we have so many examples in organic chemistry that the addition of any number of atoms of a certain increment will only modify the particular pro- perties of a body not affect its general character. Phosphoric acid .PO, Azophosphoric acid . . Pz N 0,or (PN) PO Deutazophosphoric acid . P3 N 0 or (2PN) PO,. The general resemblance between these three acids and at the same time the gradual departure from the primitive type which the more compound acids present may be well exhibited in a tabular form PHOSPHORIC ACID. AZOPHOSPHORIC ACID. Hydrated acid is stable. Hydrated acid is stable. >> , deliquescent. J9 , deliquescent. ,I , glacial. , amorphous. 1) Tribasic. Tribasic. Forms soluble salts with alkalis. Forms soluble salts with alkalis. , insoluble salts with earths. , insoluble salts with earths. , flocculent and white salts , flocculent and white salts with earths. with earths , insoluble salts with metals. , insoluble salts with metals., flocculent and mostly white , flocculent and mostly white salts with metals. salts with metals. Fe 0,salt insoluble in weak acida. Fe 0,salt insoluble in dilute acids. , , white. , $ white. DEUTAZOPHOSPHORIC ACID. Hydrated acid is stable. 1 , deliquescent. ,I , crystalline. Tribasic Forms soluble salts with alkalis. , slightly sol. salts with earths , flocculent and white salts with earths. 366 DR. GLADSTONE ON CHLOROPHOSPHURET OF NITROGEN &c. Note.-Since writing the above my attention has been drawn to a paragraph at the conclusion of a paper on Organic Combinations by M. Laur ent in the lCComptes Rendus” of the French Academy for September 9th 1850. He there remarks that the formulz assigned by me to ‘‘Chlorophosphuret of Nitrogen” and Azophosphoric acid” are quite inadmissible.He gives moreover the following as the reactions which ought to take placc in their formation C15 Ph + H3N =C12PhN+ H3C13 and 2 C12 PhN+6 H20=P206H6N+4 C1H+H3N or according to our notation P C1 + NR,= PNCI + 3 HCl and 2 PNCl,+ 12 HO=P NH Ola+ NH3+4 HCI ; and thizs he considers my ‘I azophosphoric acid” as ‘‘ pyrophosphamic acid.” In the October number of the Comptes Rendus” of Messrs. Laurent and Gerhardt these views somewhat enlarged are put forth in full detail. Yet as these eminent chemists admit in their editorial remarks that fresh experiments are necessary to verify their corrections I have little doubt that the statements contained in the present paper will satisfy them that the reactions expressed by their formulz do not really take place.Dec 2 1850. ROBERTPORRETT, EsQ. Treasurer in the Chair. The following presents were announced <‘ Memoir on the Explosiveness of Nitre,” by Robert Hare M.D. presented by the Author. ‘‘Pharmaceutical Journal for December 2’ presented by the Edit or. “Quarterly Journal of the Geological Society for September,” (No. 24 Vol. 6.j presented by the Society. “ ofversigt af Kongl. Vertenskaps- Akademiens Forhandlingar :” Sjette Argangen 1849. “Kongl. Vetenskaps-Akademiens Handlingar for ar 1848 :” presented by the Royal Stockholm Aaadeiny. An Introduction to the Atomic Theory,” by Charles Dau-beny M.D. F.R.S. presented by the Author.