Mr. Davy on a new fulminating platinum. 145 
inch of sulphuric acid diluted with -j— its volume of water was 
let up into the tube, but there was no disengagement of gas,, 
the acid slowly dissolved the powder, and the solution was 
of a very dark colour. 
Chlorine has no spontaneous action on the fulminating 
powder, but on the application of heat it is decomposed, white 
fumes are disengaged, a whitish brown sublimate of muriate 
of ammonia and a dark coloured muriate of platinum are pro- 
duced. The powder is not affected by pure liquid ammonia. 
This alkali may be boiled off' from it without impairing its 
fulminating properties. 
The powder was not apparently affected when suffered to 
remain for twelve hours in a retort filled with ammoniacal 
gas, nor did any change take place by the application of a 
gentle heat ; but when the temperature was increased, there 
was a succession of slight explosions, the powder was de- 
composed, and the metal reduced. 
When the powder was put into a retort filled with muriatic 
acid gas, there was a slight spontaneous action ; -on the appli- 
cation of heat, there was a feeble crack, the powder was de- 
composed, white vapours of muriate of ammonia were disen- 
gaged, and muriate of platinum was formed, which deliquesced 
by exposure to the air. The effects were similar when ful- 
minating gold was treated in the same way. 
Alcohol has no action on the powder. When mixed with 
flowers of sulphur and heated in a small retort, the powder 
is quietly decomposed, and sulphuret of platinum is obtained. 
When the powder is brought in contact with phosphorane, 
a hissing noise is produced, the powder appears to be par- 
JVIDCCCXVIL U 
