These are choked cases, charged with spur fire: the fire is somewhat slow, so the cases must be short: 4 inches long, and ⁵/₈ diameter is a good size. Rub the composition thoroughly up in the mortar; the vegetable black produces beautiful star-like sparks, totally dissimilar to any other. Put a little composition, at a time, into the case, and jolt it with the roman candle rammer.

Vegetable black, introduced into a star, causes it to tail, like linseed oil. Light such star on the hob; it will burn, and leave a residue, unaltered in shape; blow upon this continuously with the mouth, or, better still, with a pair of bellows: the supply of oxygen will cause it to boil up, in a state of fusion, when it will begin to throw out clusters of the peculiar starlike sparks, before mentioned, bright and yellow as new sovereigns.

Vegetable black is a pure lamp black; some samples of lamp black make equally good stars, but others are worthless. Greater reliance can be placed upon vegetable black. Vegetable black and lamp black must not be mixed with linseed oil, as such mixture is liable to spontaneous combustion.

Roll up a tube for pill boxes, of two thicknesses of brown paper. When dry, cut it into pieces about 1¹/₈ inch long: choke one end, like a wheel case; set it on a nipple,and charge it with spur fire, till full within ¹/₁₆ of an inch: fill up flush with a little plaster of paris, pressed in flat with a knife: prime the choked end, and put a number of such cases into a rocket head, or shell.