Barrils, or small barrels, designed to hold grenades, are made of pine wood. The usual dimensions are 21 inches of height, 12 inches of interior diameter at the base, and 12 1/2 of interior diameter at the mouth. The thickness of the staves should be 1 inch.
Three pounds of powder are inclosed within a canvas sack, along with four ends of an 18-inch fuse, of which 12 inches of the length should extend outside the bag. This sack is placed at the bottom of the barrel. Above it is placed a round wooden cover, with the same diameter as the barrel, in the middle of which is a hole allowing passage to the four fuses that are to give fire to the charge. On this cover are set 40 or 50 grenades, which are carefully primed and supplied with matches. A pound of ordinary composition is poured upon these. In the middle is placed a jet, which is designed, as it ceases burning, to communicate fire to the grenades and also to the bag of powder. The grenades are held in position by stuffing bits of torn paper about them. The remaining space within the barrel is filled with hay. The barrel is then closed with a cover of wood an inch thick. This sets within a hoop, and is held securely in place by pegs. In the center of the cover is a hole to allow the projection of the jet. A paper collar is pasted to the cover around the jet to maintain it in position.
When such barrels are to be discharged, holes are made in the ground, in which the barrels are set so that the tops are on a level with the surface of the soil, which is solidly packed about them.
The effect of this firework is very handsome and brilliant. It offers an agreeable contrast when used in conjunction with the cases of rockets next described. The two should be fired alternately.
As many as 20 or 30 barrels may be discharged at one time.
The cases are merely wooden boxes to contain any desired number of rockets. The rockets are set inside the box on a board, which is pierced at equal distances with holes proportioned to the thickness of the rocket sticks. The box itself should be proportioned to the length of the stick, so that the rocket may be entirely inclosed. The strip of pierced board is called the grill. A covering of paper is pasted on the grill, through which the sticks force holes when they are placed in position. The paper holds powder or a lively composition, which is poured over it to serve for communicating fire to all the rockets at the same time. The box, after having been equipped, is closed by means of a wooden cover, which is opened when the rockets are to be fired.
The principal box of this sort is called the girande. This firework is commonly employed for the termination of a display. It is provided with rockets of different sizes. The largest are placed in the middle, the medium-size next, and the smallest at the ends. This arrangement gives to. the spectacle the form of a bouquet.