The composition of the lance à feu of the French, which is used chiefly to throw occasional light across the platform, whilst artificial fire-works are preparing, and like port-fires and matches, to communicate fire, is given as follows: (Œuvres Militaires, tom xi, p. 208.)
Composition of the lance à feu.
| Saltpetre, | 3 | parts. |
| Sulphur, | 2 | —— |
| Antimony, | 2 | —— |
The lance à feu puant is of a different kind. It is the stink-fire lance, used for military purposes, and prepared in the same manner as stink-pots. They are used principally in the mine, and produce so powerful an exhalation, as to render it impossible to approach the quarter for three or four days, and occasion also, even to the miners, an apparent suffocation. The lance de feu, however, is a different preparation from either. It is a species of squib, which is used by the garrison of a besieged town against a scaling party. For the preparation of fire lances, see the subsequent part.
Sec. XIX. Of Slow White-flame Lances.
The composition of this lance, or port-fire, is such, that it will burn longer than the ordinary lance. There are two formulæ given for it. Both compositions, when driven one and a quarter inches in an ounce case, will burn one minute, which is considered by some a much longer time than an equal quantity of any composition, yet known, will last.
Composition of slow Fire.
| 1. | Saltpetre, | 2 | lbs. | 2. | Saltpetre, | 3½ | lbs. |
| Sulphur, | 3 | lbs. | Sulphur, | 2½ | lbs. | ||
| Antimony, | 1 | lb. | Meal-powder, | 1 | lb. | ||
| Antimony, | ½ | lb. | |||||
| Glass-dust, | ¼ | lb. | |||||
| Brass-dust, | 1 | oz. |
Sec. XX. Of Lights.
We purpose hereafter to treat particularly of the Chinese lights, Bengal lights, amber lights, blue lights, &c. We will merely mention in this place, the composition of some of them.