This is the mixture of gases obtained by a red heat from coal and oil, after being freed from carbonic acid, &c., by the usual means.
This mixture requires a very complicated formula, in consequence of the specific gravities of the gases entering into the calculus. The importance of the subject however may be an apology for the labour.
| Let x = | vol. of superolefiant, S its sp. gr. |
| y = | vol. of carb. hydrogen, f its sp. gr. |
| z = | vol. of carbonic oxide, c its sp. gr. |
| & u = | vol. of hydrogen, s its sp. gr. |
C = specific gravity of the mixture, g = oxygen, a = carbonic acid, and w = whole volume of mixture as before.
| Then we have x + y + z + u = | w |
| 4½x + 2y + ½z + ½u = | g |
| 3x + y + z = | a |
| and Sx + fy + cz + su = | Cw. |
| Whence u = | |
| (3S + 5c - 8f)a - (4c - 4f)g - (3S + 6C - 6f - 3c)w | |
| 8f + c - 3S - 6s. | |
The value of the hydrogen being obtained, it may be subtracted from w, and the remainder will be best divided into three portions, by the preceding formula.
HEAT PRODUCED BY THE
COMBUSTION OF GASES.
Subsequent experience to that detailed at page 77, Vol. 1. has furnished the following more correct results of the heat produced by the combustion of pure gases.
| Hydrogen, combustion of it raises an equal volume of water | 5° |
| Carbonic Oxide | 4½ |
| Carburetted Hydrogen, or Pond Gas | 18 |
| Olefiant Gas | 27 |
| Coal Gas (varies with the gas from 10° to) | 16 |
| Oil Gas (varies also with the gas from 12° to) | 20 |
Generally the combustible gases give out heat nearly in proportion to the oxygen they consume. See note at the end of Vol. 4, new series of the Manchester memoirs.