Fig. 21, a view of the front of the guide facing the reammer. M, an iron plate, of the same dimensions as that on the front of the box, and placed in the same direction, and also to turn on a screw in the center. N, the rocket box, which slides backwards and forwards: when you have fixed a rocket in the box, push it forwards against the reammer; and when you think the scoop of the reammer is full, draw the box back, and knock out the composition; this you must do till the rocket is bored, or it will be in danger of taking fire; and if you bore in a hurry, wet the end of the reammer now and then with oil to keep it cool. Having bored a number of rockets, you must have taps of different sorts according to the rockets. These taps are a little longer than the bore, but when you use them, mark them three diameters and a half from the point, allowing for the thickness of the rocket’s neck; then, holding the rocket in one hand, you tap it with the other. In order to explain these taps, I have represented one by Fig. 22. They are made in the same proportion as the fixed piercers, and are hollowed their whole length. Of a Hand Machine used for boring of Rockets instead of a Lathe. Those sort of machines answer very well, but not so expeditious as the lathe, nor are they so expensive to make; they may be worked by one man; but the lathe will require three. Fig. 23, represents the machine. O, the rocket boxes, which are to be fixed and not to slide as those in the lathe. P Q, are guides for the reammers, that are made to slide together, as the reammer moves forward: the reammers for these sort of machines must be made of a proper length, allowing for the thickness of the front of the boxes, and the length of the mouth and neck of the case: on the square end of these reammers, must be a round shoulder of iron, to turn against the outside of the guide Q, by which means the guides are forced forwards. R, the stock which turns the reammer, and while turning must be pressed towards the rocket, by the body of the man who works it; all the reammers are to be made to fit one stock. This machine as well as the lathe is made by the scale in the same plate. The Manner of making large Gerbes.