Mr. E. Howard on a new fulminating Mercury. 215 



sive; otherwise, not only the pure red oxide, but the red nitrous 

 oxide, and turpeth, may be substituted; neither does it seem 

 essential to attend to the precise specific gravity of the acid, or 

 the alcohol. The rectified spirit of wine and the nitrous acid of 

 commerce, never failed, with me, to produce a fulminating 

 mercury. It is indeed true, that the powder prepared without 

 attention, is produced in different quantities, varies in colour, 

 and probably in strength. From analogy, I am disposed to 

 think the whitest is the strongest; for it is well known, that black 

 precipitates of mercury approach the nearest to the metallic 

 state. The variation in quantity is remarkable; the smallest 

 quantity I ever obtained from 100 grains of quicksilver being 

 120 grains, and the largest 132 grains. Much depends on very 

 minute circumstances. The greatest product seems to be ob- 

 tained, when a vessel is used which condenses and causes most 

 ether to return into the mother liquor ; besides which, care is to 

 be had in applying the requisite heat, that a speedy, and not a 

 violent action be effected. 100 grains of an oxide are not so 

 productive as 100 grains of quicksilver. 



As to the colour, it seems to incline to black, when the action 

 of the acid on the alcohol is most violent, and vice versa. 



section x, 



I need not observe, that the gases which were generated 

 during the combustion of the powder in the glass globe, were 

 necessarily mixed with atmospheric air ; the facility wi h which 

 the electric fluid passes through a vacuum, made such a mixture 

 unavoidable. 



The cubical inch of gas received over water was not readily 



