Mr. Davy on a new fulminating platinum. 14,7 
from its decomposition were more numerous, and the odour 
of ammonia could not be perceived. When, however, a few 
drops of water were added to the mixture of dried quicklime 
and fulminating powder, ammonia was produced by the appli- 
cation of heat. When the powder was put into a small retort 
with pure muriatic acid, the fluid boiled to dryness, and the 
dry mass heated to redness, the platinum remained in the 
metallic state, and a whitish sublimate was deposited in the 
neck of the retort, which, when collected and mixed with 
quicklime, spontaneously evolved ammonia. 
When nitrous acid was boiled to dryness on the powder, 
and the heat continued, a quantity of gas was obtained, which 
appeared to be nitrous oxide, as it enlarged the flame of a 
taper and was absorbed by water, and oxide of platinum alone 
remained in the retort. 
The foregoing results appear to furnish satisfactory evi- 
dences as to the nature of fulminating platinum, that it is a 
compound of oxide of platinum and ammonia. From the 
following experiments, I shall venture to deduce the propor- 
tions of its constituent parts. In the analysis, I employed 
muriatic- acid and sulphur to ascertain the quantity of plati- 
num, and nitrous acid to determine the proportion of oxide in 
the fulminating compound; and the coincidence, between 
results obtained by such different methods, affords strong 
presumptions as to the accuracy of the experiments. 
Exp. 1. Ten grains of the fulminating powder were put into 
a small retort with pure muriatic acid, the retort was heated 
over water so as to boil the fluid to dryness and decompose 
the dry mass; no permanently elastic fluid came over, except 
the common air in the retort ; a grey substance sublimed, 
U2 
