194 FULMINATING MERCUR7. 



been separated, was found, by the test of nitrous gass, to contain 

 nitrogen or azotic g;is ; which docs not proceed from any d<>compa- 

 sition of atmospheric air, because the powder may be made to ex- 

 plod*- under the exhausted receiver of an air-pump. It is there- 

 fore manifest that the gasses generated during the combustion of 

 the fulminating mercury, consist of carbonic acid and nitrogen 

 gasses. 



u Th" principal re-agent* which decompose the mercurial pow- 

 der are the nitric, the sulphuric, and the muriatic acids. The nitric 

 changes the whole into nitrous gass, carbonic acid gass, acetout 

 acid, and nitrate of mercury. I resolved it into these different 

 principles, by distilling it pneumatically with nitric acid : this 

 acid upon the application of heat soon dissolved the powder, and 

 extricated a quantity of gass, which was found, by well-known 

 tests, to be nitrous gass mixed with carbonic acid gass. The dis- 

 tillation was carried on until gass no longer came over. The 

 liquor of the retort was then mixed with the liquor collected in 

 the receiver, and the whole saturated with potass ; which precipi- 

 tated the mercury into a yellowish brown powder, nearly as k 

 would have done from a solution of nitrate of mercury. This pre- 

 cipitate was separated by a filter, and the filtrated liquor evapo- 

 rated to a dry salt, which was washed with alcohol. A portion of 

 the salt being refused by this menstruum, it was separated by fil- 

 tration, and recognized, by all its properties, to be nitrate of 

 potass. The alcohol liquor was likewise evaporated to a dry salt, 

 which upon the effusion of a little concentrate sulphuric acid, 

 emitted acetous acid, contaminated with a feeble smell of nitrous 

 acid, owing to the solubility of a small portion of the nitre in the 

 alcohol. 



" The sulphuric acid acts upon the powder in a remarkable man- 

 ner, as has already been noticed. A very concentrate acid pro. 

 duced an explosion nearly at the instant of contact, on account, I 

 presume, of the sudden and copious disengagement of caloric from 

 a portion of powder which is decomposed by the acid. An acid 

 somewhat less concentrate likewise extricates a considerable quan. 

 tity of caloric, with a good deal of gass; but as it effects a com- 

 plete decomposition, it causes no explosion. An acid diluted with 

 an equal quantity of water, by the aid of a little heat, separates the 

 gass so much less rapidly, that it may with safety be collected in a 

 pneumatic apparatus. But, whatever be the density of the acid 



