154 Mr. Davy on a new fulminating platinum. 
ment to which I allude, one grain of the powder afforded 
0.18 of a cubic inch of gas, 0.15 of which had the properties 
of nitrogene, and 0.03 appeared to be ammonia. This, how- 
ever, is not to be considered as the true quantity that a grain 
would yield, for reasons already stated ; but even on this 
calculation, 100 grains of the powder would furnish 15 cubic 
inches of nitrogene, and 3 of ammonia. 
15 cubic inches of nitrogene weigh about 4.42 grs. and require 
45 cub. in. of hydrogene (to form ammonia) 1.01 
3 cubic inches of ammoniacal gas 0.54 
5.97 of ammonia in 
100 grains of the powder, calculating only from the quantity 
of gas actually obtained, without taking into account the 
quantity of ammoniacal gas absorbed by the water present, 
which must have been saturated with this gas. The water 
arose from two sources it formed a constituent part of the 
powder, and it was generated from its elements during the 
explosion. The quantity of water formed would be 8.66 
grains. The 1.01 grain of hydrogene would require for this 
purpose 7.65 grains of oxygene.* I found that 8J grains of 
water absorbed about one grain of ammoniacal gas, the 
thermometer being at 6o°, and barometer at 30°; consequently, 
the 8.66 grains of water generated from 100 grains of the 
powder, would take up rather more than a grain of ammonia. 
And if we suppose the water contained in the powder to 
amount to about 8|- per cent., (and it can scarcely be more,) 
* In estimating the weights of the respective gases, and the proportions in which 
they combine, I have adopted the statements of Sir Humphry Davy in his “ Ele- 
ments of Chemical Philosophy.” 
