This cord or chain runs upon two fixed pulleys, placed for instance, at the two extremities of a battery, and is managed by artillerists. The pyrophore is under cover. When it is conveyed to a certain place, where a bar or grate is fixed, it is stopped, by the contrivance before mentioned, the lid is raised, and the powder falls into a kind of funnel or gutter, at the end of which the explosion is made, to take effect.
It appears that the inventor had in view the conveyance of a given quantity of powder to a particular place, and by carrying a light to it by means of a cord, similarly fixed, to inflame it, when it had arrived at its destination.
It is impossible to make a machine of this kind effective; for the difficulty in arranging, and finally managing it, the enemy taking means to guard against it, are certainly obstacles, and strong objections to its use. Other means of defence, which we have pointed out, are preferable; although we admit, that, in some situations, a contrivance of this sort might be advantageously used, where, for instance, we wish to deposite a quantity of powder, to be in readiness for the approach of an enemy, without exposing men to an attack. What is more destructive than the thundering barrel, which is furnished with grenades, &c. &c. if set off among the assailants? See, for a minute account of this contrivance, the "Pyrophore, ou Moyen de defense générale, par un garde national: 20 pages grand in 8vo. avec un planche. Paris Dondey Dupré, 1815," and also the Archives des Découvertes, tome 8. p. 281.
[VOCABULARY]
OF FRENCH TERMS, WHICH OCCUR IN THE WORK.
Aigremore. Pulverized charcoal, proper for fire-works.
Aigrette. An imitation in fire of the aigrette; like the aigrette of glass.
Ailerons. They are used in making rockets.