14 ∈. JOHN f). EDWARDS ON THE ACTION OF Jan. 14 1850. The PRESIDENT in the Chair. The following presents were announced ‘‘ Ofversigt af Kongl. Vertenskaps-Academiens.” Forhandlingar 184s. “An Introductory Lecture on the importance of the study of Chc-mistry,” and the (‘Arsberattelse om framstegen i Kemi,” under iir I84 7 af L. F. Svanberg. The January number of the “ Pharmaceutical Journal,” presented bj the Editor. cc On the Nitro-prussides by Lyon Play fair Ph.D.” (Phil. Trans. 1849 p. 477) from the Author. The November number of the cc Jouriial of the Franklin Institute,” from the Institute The following papers were read 111.-On the action of Arsenious Acid upon Albumen. Bg JOHNB. EDWARDS, F.C.S. The attention of the Liverpool Chemists’ Association has been recently directed to the above subject by Dr.Brett in two Lectures upon Arscnic; and feeling interested in it I have since made several experiments with a view of determining whether arsenious acid com-bines with albumen in atomic proportion as believed by Professor Liebig,* or whether such a compound is not a mere mechanical mixture of the two substances. Liebig states that 100 grs. of albumen combines with lt grs. of arsenious acid and that it is in virtue of the powerful affinity existing between these bodies that life is destroyed when they are brought together in the living organism. I shall not notice on this occasion the physiological and patholo- gical objections to this view which were ably urged by Dr.Brett on the occasions referred to but proceed to detail my experiments and notice the objections arising therefrom to the cc Chemical Theory.” * Animal Chemistry p. 3G1 ARSENIOUS ACID UPON ALBUMEN. I took 1 gr. of opaque arsenious acid in perfect solution in water and 100 grs of the glairy albumen of eggs thoroughly mixed them by trituration and coagulated by heat ;the filtrate contained a con-siderable quantity of arsenious acid The coagulate was well washed with distilled water and the washing gave a deposit of arsenic on copper by Reinsch’s test; 4 oz. of the same gave by Marsh’s apparatus a number of large stains on porcelain which gave evidence of being arsenic by the silver copper and sulphide of hydrogen tests. The coagulate was well washed and bruised in a mortar till the filtered liquid gave no indications of arsenic by Reinsch’s test ; the coagulate was then destroyed by sulphuric acid neutralized and tested by the same method; not the slightest deposit could be ob- tained though boiled for half an hour but on the addition of a solution containing -i-ij-$8th part of a grain of arsenious acid the copper was immediately stained No combination therefore could have taken place for the whole of the acid was removed by patient trituration with hot water.This leads me to think that other expe- rimenters who have not detected arsenic in their washings have neglected thoroughly to break up the mechanical network of the coagulate. I repeated this experiment six times varying the propor- tions and the circumstances; but in each case my result was the same.In one experiment in which I used 100grs. of albumen and 8 gr. only of arsenious acid I detected arsenic in five or six washings and afterwards failed to detect it in the coagulate when decomposed. In another case I whisked the albumen with water for some minutes in order to destroy the organic structure and then digested for two hours at 98O F. before coagulating ;boiling water soon dissolved the whole of the arsenious acid and none could be detected in the washed coagulate. I then took warm sheep’s blood before congelation 960 grs. ; arsenious acid in solution 2grs.; digested at 98O for three hours and then coagulated. In this case also the whole of the acid was removed by boiling water.I next took 1000 grs. blood and.5 grs. arsenious acid ;digested at 9S0,as before for two hours then coagu- lated; by repeated boiling I extracted the whole of the acid the residue giving no trace by Reinsch’s test; I then evaporated the washings to dryness at a low temperature redissolved in hot water and through the filtered solution passed a current of hydrosulphuric acid gas. I collected the tersulphide of arsenic thus formed washed and dried by a water-bath ;the precipitate weighed 5.8 grs. ON THE ACTlON OF ARSENIOUS ACID UPON ALBUMEN. According to theory 5 grs. of ursenious acid would be equivalent to 6.22 of the tersulphide. The correspondence of the abovcx result proves that the whole of the acid was removed by boiling water.0 I took the coagulate obtained from 2 grs. acid and 200 grs. albu- men washed it with cold water and gave it to a healthy young rabbit; it was violently purged and died in about ten hours. Upon examination the stomach was found infl anied with extia-vasation of blood in patches amounting in one or two spots to positive ulceration,-also considerable vascularity of the trachea bron- chial tubes and intestines. The coagulate was found in the stomach undigested the rabbit being a herbivorous animal; the acid had been simply dissolved by the juices of the stomach without decom- position of the albumen. I then offered the same quantity to a remarkably fine healthy guinea-pig; it refused to take the whole and I suppose about I.$ grs.of arsenious acid was actually taken. It was purged frothed at the mouth and died in about sixteen hours. The stomach and other organs were found mizch more violently inflamed than those of the rabbit probably on account of its living longer. iVo coayailate was found in the stomach; it was therefore digested this being an omnivorous animal. The soft organs of the rabbit were examined by Dr. Brett. He found arsenic in each. After finding a large quantity in the mucous coat of the stomach he submitted that organ to a continuous stream of water for some time; when he could no longer detect arsenic in the washings he decomposed the tissue with nitric acid neutralized and boiled for a considerable time with Reinsch’s test but was unable to detect arsenic.I examined several organs and muscles of the guinea-pig and found arsenic in each I also treated the stomach of this animal in the same manner and removed the whole of the arsenic by hot water. Whatever objections may be raised to the first experiments with albumen I think the facts proved by the latter are weighty argu- ments against Liebig’s views. If water so readily extracts arsenious acid both from the compounds formed in the laboratory and from those which nature has prepared surely we may conclude that its retention is simply mechanical and affords no ground for the theory which that eminent chemist has raised upon it.