Mr. E. Howard on a new fulminating Mercury. 217 



and the filtrated liquor evaporated to a dry salt, which was 

 washed with alcohol. A portion of the salt being refused by this 

 menstruum, it was separated by filtration, and recognized, by all 

 its properties, to be nitrate of potash. The alcoholic liquor was 

 likewise evaporated to a dry salt, which, upon the affusion of a 

 little concentrate sulphuric acid, emitted acetous acid, contami- 

 nated with a feeble smell of nitrous acid, owing to the solubility 

 of a small portion of the nitre in the alcohol. 



SECTION XII. 



The sulphuric acid acts upon the powder in a remarkable 

 manner, as already has been noticed. A very concentrate acid 

 produces an explosion nearly at the instant of contact, on 

 account, I presume, of the sudden and copious disengagement 

 of caloric from a portion of the powder which is decomposed by 

 the acid. An acid somewhat less concentrate likewise extricates 

 a considerable quantity of caloric, with a good deal of gas ; but, 

 as it effects a complete decomposition, it causes no explosion. 

 An acid diluted with an equal quantity of water, by the aid of a 

 little heat, separates the gas so much less rapidly, that it may 

 with safety be collected in a pneumatic apparatus. But, what- 

 ever be the density of the acid, (provided no explosion be pro- 

 duced, ) there remains in the sulphuric liquor, after the separation 

 of the gas, a white uninflammable and uncrystallized powder, 

 mixed with some minute globules of quicksilver. 



To estimate the quantity, and observe the nature, of this un- 

 inflammable substance, I treated 100 grains of the fulminating 

 mercury with sulphuric acid a little diluted. The gas being 

 separated, I decanted off the liquor as it became clear, and freed 

 the insoluble powder from acid, by edulcoration with distilled 



mdccc F f 



