132 Dr.W6hlero)ia [Feu. 



oxide of silver, I mixed pretty concentrated solutions of the two 

 compounds : contrary to my expectation, no precipitate fell ; but 

 after a few minutes there was deposited a number of small white 

 crystals, whose quantity greatly exceeded that of the cyanuret 

 of mercury which I had employed. They were repeatedly 

 washed with water, and dried. 



When these crystals are heated in a temperature above 212°, 

 they fuse in the first place into a transparent liquid ; by and 

 bye they boil up and detonate vehemently, with a crackling- 

 noise, and a purphsh red coloured flame, closely resembling that 

 which accompanies the combustion of cyanogen. The residue 

 consists of cyanuret of silver, and, by continued ignition in the 

 open air, is converted into metallic silver. If the experiment 

 be performed in a glass tube, a quantity of mercury is also sub- 

 limed. Muriatic acid, poured upon the crystals, instantly disen- 

 gages hydrocyanic acid, and after the whole of the latter has 

 been expelled by the application of heat, there is given off a 

 strong odour of chlorine : the liquid, evaporated to dryness, 

 leaves a mixture of the chlorides of silver and mercury. If a 

 solution of the crystals be precipitated by muriate of barytes, 

 and if the filtered liquid be evaporated, there is obtained asahne 

 mass, containing abundance of octohedral crystals of nitrate of 

 barytes. From the saline mass alcohol extracts cyanuret of 

 mercury. Consequently this crystallized substance is a com- 

 pound of cyanuret of mercury and nitrate of oxide of silver. 



This compound is very difficultly soluble in cold, but rather 

 copiously in hot water, and as the solution cools, it crystallizes 

 in large transparent prisms, having the form of saltpetre. It 

 may be obtained in large crystals also by mixing hot solutions 

 of the cyanuret of mercury and nitrate of silver; the crystals 

 appearing as the liquid cools. Alcohol appears to dissolve it 

 in nearly the same proportions as water. In boiling hot nitric 

 acid it is soluble without decomposition. Alkalies precipitate 

 from its aqueous solution cyanuret of silver, which appears to 

 be mixed with subnitrate of oxide of mercury. Repeated solu- 

 tions in pure water produce a similar decomposition ; but only 

 to a very inconsiderable extent. 



When these crystals are heated in a temperature rather below 

 212°, they give off water, and become white coloured and 

 opaque, without losing their original form. 100 parts, thus 

 treated, lost 7-6 parts of water. 



To determine the quantity of silver, 1 gramme of the crystals 

 was treated with an excess of muriatic acid, and the mixture 

 was cautiously evaporated to dryness. The corrosive sublimate 

 being now expelled from the dry mass by ignition, there remained 

 0"32 gramme of fused chloride of silver. This is equivalent to 

 0"2588 gramme of oxide of silver, and consequently indicates. 

 37*96 per cent, of nitrate of oxide of silver. The quantity of 



