But this theoretical account of the gases developed does not well accord with the experimental products usually assigned, though these are probably not altogether exact. Much carbonic acid is said to be disengaged, a large quantity of nitrogen, a little oxide of carbon, steam of water, with carburetted and sulphuretted hydrogen. From experiments to be presently detailed, I am convinced that the amount of these latter products printed in italics must be very inconsiderable indeed, and unworthy of ranking in the calculation; for, in fact, fresh gunpowder does not contain above one per cent. of water, and can therefore yield little hydrogenated matter. Nor is the hydrogen in the carbon of any consequence.
It is obvious that the more sulphur is present, the more of the dense sulphurous acid will be generated, and the less forcibly explosive will be the gunpowder. This is sufficiently confirmed by the trials at Essonne, where the gunpowder that contained 12 of sulphur and 12 of charcoal in 100 parts, did not throw the proof-shell so far as that which contained only 9 of sulphur and 15 of charcoal. The conservative property is, however, so capital, especially for the supply of our remote colonies and for humid climates, that it justifies a slight sacrifice of strength, which at any rate may be compensated by a small addition of charge.
Table of Composition of different Gunpowders.
| Nitre. | Charcoal. | Sulphur. | ||||
|---|---|---|---|---|---|---|
| Royal Mills at Waltham Abbey | 75 | 15 | 10 | |||
| France, national establishment | 75 | 12 | ·5 | 12 | ·5 | |
| French, for sportsmen | 78 | 12 | 10 | |||
| French, for mining | 65 | 15 | 20 | |||
| United States of America | 75 | 12 | ·5 | 12 | ·5 | |
| Prussia | 75 | 13 | ·5 | 11 | ·5 | |
| Russia | 73 | ·78 | 13 | ·59 | 12 | ·63 |
| Austria (musquet) | 72 | 17 | 16 | |||
| Spain | 76 | ·47 | 10 | ·78 | 12 | ·75 |
| Sweden | 76 | 15 | 9 | |||
| Switzerland (a round powder) | 76 | 14 | 10 | |||
| Chinese | 75 | 14 | ·4 | 9 | ·9 | |
| Theoretical proportions (as above) | 75 | 13 | ·23 | 11 | ·77 | |
6. On the Chemical Examination of Gunpowders.
I have treated five different samples: 1. The government powder made at Waltham Abbey; 2. Glass gunpowder made by John Hall, Dartford; 3. The treble strong gunpowder of Charles Lawrence and Son; 4. The Dartford gunpowder of Pigou and Wilks; 5. Superfine treble strong sporting gunpowder of Curtis and Harvey. The first is coarse-grained, the others are all of considerable fineness. The specific gravity of each was taken in oil of turpentine: that of the first and last three was exactly the same, being 1·80; that of the second was 1·793, all being reduced to water as unity.
The above density for specimen first, may be calculated thus:—
| 75 parts of nitre, specific gravity | = | 2·000 |
| 15 parts of charcoal, specific gr. | = | 1·154 |
| 10 parts of sulphur, specific gr. | = | 2·000 |
The volume of these constituents is 55·5, (the volume of their weight of water being 100;) by which if their weight 100 be divided, the quotient is 1·80.