We may here remark, that large cases for serpents, as well as wheel cases, are driven solid. There is usually a mould, in which is a nipple, with a point at top, that serves, when the case is filling, to stop the neck, and prevent the composition from falling out. The air, in that event, would get into the case, and cause it to burst. These sorts of moulds are made of any length or diameter, as the cases are required; but the diameter of the form must be equal to half the caliber, and the rammers solid.

Lardons are of much the same nature as serpents, but are made stronger. They are charged in the same manner. To prime them, they are first pierced about five or six lines (or half an inch,) in depth, which presents a greater surface to the fire, and produces, when inflamed, more scintillations than serpents.

Composition of ordinary serpents.

1st proportion,2nd proportion.
Meal powder, 16 parts.
Saltpetre,3do.15 parts.
Sulphur,2do.4do.
Charcoal,½do.2½do.
Mine pots, or Serpents.
Meal powder,1lb.
Charcoal,1oz.
Ibid.
Meal powder,9oz.
Charcoal,1—
Serpents for Pots de Brins.
Meal powder,1½lbs.
Saltpetre,12oz.
Charcoal,2—

The serpents or snakes for pots of aigrettes, small mortars, skyrockets, &c. are made from two and a half inches, to seven inches long. Their formers are from three-sixteenths to five-eighths of an inch in diameter; but the diameter of the cases must always be equal to two diameters of the former. They are rolled and choaked like other cases, and filled with composition, five-eighths of an inch to one and a half inches high, according to the size of the mortars or rockets, they are designed for. The remainder of the cases are charged or bounced with grained powder, and their ends pinched and tied close. Before they are used, their mouths must be primed with wet meal powder or priming paste as before-mentioned.

Serpents, or snakes, in fire-works, are so called from the particular appearance, and the effect which ensues, namely, a hissing and spitting. This peculiar character is given by the charcoal; for, while one part is actually consumed, in immediate contact with the substances that enter into the composition; another part is thrown out with violence in the state of ignition, in the form of sparks, and receives, for the support of its combustion, the oxygen of the air, in consequence of which carbonic acid is produced.

Sec. II. Of Crackers.

Crackers are made in the following manner; cut some cartridge paper into pieces, three and a half inches broad, and one foot long. One edge of each paper fold down lengthwise, about three-quarters of an inch broad. Then fold the double edge down one quarter of an inch, and turn the single edge back half over the double fold. Open it, and lay all along the channel, which is formed by the folding of the paper, some meal powder. It must now be folded over and over till all the paper is doubled up, rubbing it at every turn. It is now to be bent backwards and forwards, two and a half inches or more, as often as the paper will allow. These folds are to be held flat and close; and, with a small pinching cord, give one turn round the middle of the cracker, and pinch it close. Bind, as usual, with pack thread, in the place where it was pinched. Prime one end of it, and cap it with touch paper. When these crackers are fired, they will give a report at every turn of the paper. If there are to be a great number of bounces, the paper must be cut longer, or be joined after they are made. If, however, they are made very long before they are pinched, there must be a piece of wood, having a groove sufficiently deep to let in half the cracker, which will hold it straight, while it is pinching.