In certain pieces, exhibitions of this kind are made. They are formed in such a way, as to make them throw fire from the mouth, nose, and ears, which is blown out into the air. Cases, charged with brilliant fire, are so arranged that their fire may act all at the same time. Puffs may also be produced to go out at the mouth, by means of a tube or funnel, placed behind the monster. These preparations and exhibitions are so susceptible of variations, that, having a previous knowledge of the composition and effect of the fire-work, it may be so arranged as to produce a variety of appearances.
Sec. VIII. Of Lightning.
The effect of lightning may be shown by several preparations. Lycopodium, or puff-ball, is the substance most commonly employed. When it cannot be procured, rosin may be substituted; and, generally, as the latter is cheaper, it is used. Rosin, reduced to an impalpable powder, and thrown upon a flame, will produce the effect in a remarkable degree, and when blown through a tube, the effect is more striking.
Several fluid substances, when ejected from a syringe on a lighted candle, have the same appearance. Alcohol has this effect. The difficulty of preparing and employing them, has given the lycopodium a preference.
A tin or brass tube, larger at one end than the other, and covered at the former end, with a cover, perforated with holes, similar to the branch of a watering pot, is used for holding the composition, or substance made use of. Through this cover, or lid, a cotton wick is put, which, before lighting, is well soaked in alcohol or spirits of wine. When lighted, the torch or tube, containing the lycopodium, or rosin, is shaken at the smaller extremity; when these substances will pass through the holes in small quantities, and be successively inflamed.
Sec. IX. Of the Artifice of Destruction.
When, in any exhibition, palaces, castles, or forts are to be demolished, or thrown down, there are about twenty petards fixed on rods. Petards, for this use, are made with cases, and sometimes with wheels. The cases are generally three-quarters of an inch in diameter, charged with grain powder, and choaked at both ends. They are arranged in a zigzag direction.
This series of crackers has a fine effect. It is obvious, that, in all these exhibitions, intelligent artizans may employ various descriptions of artificial fire, where, in particular, it often seems, that there is something yet to be wished for.
Sec. X. Of the Spur-fire.