= 
Miscellanies. 191 
ting. Hence analysis may show a small deficit of charcoal below the 
synthetic proportions originally mixed. The residuum of charcoal and 
sulphur left on the double filter paper, being well dried by the heatof or- 
dinary steam, is estimated as usual by the difference of weights of the in- 
nerand outer papers. This residuum is cleared off into a platina cap- 
sule with a tooth-brush, and digested in a dilute solution of potash at 
aboiling temperature. Three parts of potash are fully sufficient to 
dissolve out one of the sulphur. When the above solution is thrown 
ona filter and washed first with a very dilute solution of potash boil- 
ing hot, then with boiling water, and afterwards dried, the carbon will 
remain; the weight of which deducted from that of the powder will 
show the amount of sulphur.” 
Dr. Ure says that he has tried other and more direct modes of es- 
timating the sulphur, but with little satisfaction ; such as dissolving it 
by means of hot oil of turpentine, its conversion into sulphurie acid 
by the use of nitric acid and chlorine, &c. 
“If we acquire” says Dr. Ure, “how the maximum gaseous vol- 
une is to be produced from the chemical reaction of the elements of 
hitre on charcoal and sulphur, we shall find it to be by the generation 
of carbonic oxide and sulphurous acid, with the disengagement of ni- 
gen. This will lead us to the following proportions of these con- 
stituents:—1 prime equiv. of nitre 102 75.00 per cent. 
1 
do sulphur 16 at: 
3 do charcoal is 13.23 
136 100.00 
~The (acid of the) nitre contains five primes of oxygen, of which 
three, combining with the three of charcoal will furnish three of car- 
bonic acid gas, while the remaining two will convert the one prime of 
sulphur into sulphurous acid gas. The single prime of nitrogen is, 
in this view disengaged alone. : 
€ gaseous volume, on this supposition, evolved from 136 grains 
of gunpowder, equivalent in bulk to 75 grains of water, or three- 
ms of a cubic inch, will be, at the atmospheric temperature, as fol- 
OWs: 
Grains. Cubic inches. 
Carbonic oxide, - - 42 - . 141.6 
Sulpurous acid, - F eee = a eres 
Nitro en, s = 14 = - ATA 
Being an expansion of one volume into 787.3. But as the tempera- 
lure of the gases at the instant of their combustive formation must be 
‘neandescent, this volume may be safely estimated at three times the 
‘ove amount, or considerably upwards of two thousand times the 
bulk of the explosive solid.” —Idem. 
