ARSENIATED HIDROGEN GA3, 209 



as long as a minute quantity of arfenic was prefent, a black 

 precipitate enfued> whereas pure hidrogen has no effed upon 

 this re-agent, 



I pafTed into a concentrated folution of nitrate of filver, a 

 ftream of arfeniated hidrogen, collected the black metallic 

 precipitate, wadied and dried it. The fluid obtained in this 

 procefs did not dillurb the tranfparency, or change the co- 

 lour of ammoniate of copper. Neither liquid fulphurated 

 hidrogen, tindure of galls, nor potafti, had any eff'e<5l upon 

 it. It contained therefore neither filver nor arfenic. The 

 precipitate before obtained, acquired a metallic luftre on be- 

 ing faturated ; laid on ignited coals, it diffufed an odour of 

 arfenic^ and it yielded by fufion a button of filver. It was an 

 arfeniate of filver. 



Arfeniated hidrogen pafled into a folution of nitro-muriate Nltro-munaw 

 of gold, occafioned a precipitate ; on the furface of the °^ 8°'*^* 

 fluid appeared a pellicle of metallic gold ; and the fides of 

 the veflel, in contact with the fluid, became beautifully 

 gilded. The fluid through which ,the gas had been pafled, 

 examined in the ufual manner, proved to contain no veftige 

 either of gold or arfenic. The precipitate greatly refembled 

 charcoal duft, interfperfed with minute particles of gold. 



It is highly probable, that arfeniated hidrogen is capable of Decompofesme* 

 decompofing all metallic folutions, the bafis of which is either ^^"'^'^ folutions. 

 nitric, or muriatic acid, and probably other acids. 



Habitudes of arfeniated Hidrogen Gas to various other Bodies. 



Exprefled oils, on being agitated for fome time in contact Its habitudes 

 with arfeniated hidrogen, abforbed part of the gas, and ac- *^? expreffed 

 quired a deeper colour. 



Alcohol fuffers no change from arfeniated hidrogen. Solu- and to alcohol, 

 tion of potafti, and liquid ammonia, do not abforb it. ^° 



Such are the properties of this gas, the inveftigation of 

 which I fliall continue as foon as my health is reftored, it be- 

 ing fo confiderably injured by the unavoidable inhalation of 

 this gas during the courfe of thefe experiments, which gives 

 me ample reafon to conclude, that the gas muft be highly 

 poifonous. 



D. J. B. TROMSDORFF. 



Effurth, Feb. 1803. 



Vol. VI. —November, 1803. P Account 



