Fig. 10, 11, 12, and 13, represent another mode of arranging the different natures of ammunition, which is hitherto merely a matter of speculation, but which may in certain parts of the system be hereafter found a considerable improvement. It is the carrying the Rocket, or projectile force, distinct from the ammunition itself, instead of combining them in their first construction, as hitherto supposed. Thus, Fig. 10 is the Rocket, and Fig. 11, 12, and 13, are respectively a shell, case shot, or carcass, which may be immediately fixed to the Rocket by a screw, according as either the one or the other nature is required at the time. A greater variety of ammunition might thus be carried for particular services, with a less burthen altogether. Fig. 14 and 15 represent the light ball or floating carcass Rocket. This is supposed to be a 42-pounder Rocket, containing in its head, as in Fig. 12, a parachute with a light ball or carcass attached to it by a slight chain. This Rocket being fired nearly perpendicularly into the air, the head is burst off at its greatest altitude, by a very small explosion, which, though it ignites the light ball, does not injure the parachute; but by liberating it from the Rocket, leaves it suspended in the air, as Fig. 13, in which situation, as a light ball, it will continue to give a very brilliant light, illuminating the atmosphere for nearly ten minutes; or as a carcass, in a tolerable breeze, will float in the air, and convey the fire for several miles, unperceived and unconsumed, if only the match of the carcass be ignited at the disengagement of the parachute. It should be observed that, with due care, the Rocket ammunition is not only the most secure, but the most durable that can be: every Rocket is, in fact, a charge of powder hermetically sealed in a metal case, impervious either to the ordinary accidents by fire, or damage from humidity. I have used Rockets that had been three years on board of ship, without any apparent loss of power; and when after a certain period, which, from my present experience, I cannot estimate at less than eight or ten years, their force shall have so far suffered as to render them unserviceable, they may again be regenerated, at the mere expense of boring out the composition and re-driving it: the stick, case, &c. that is to say, all the principal parts, being as serviceable as ever. [Illustration: _Plate 13_ Figs. 1–15] _The Ranges of these different Natures of Rocket Ammunition are as follow:_