Thus, he may form a Rocket Battery of any common epaulement, parallel to the face of the town to be bombarded, by digging a trench in the rear of it to admit the stick, so as to lay the Rocket and stick against the slope of the epaulement, that slope being brought to the desired elevation for projecting the Rocket, or by boring holes to receive the stick; or he may construct a slope expressly as a Rocket Battery; and as, in firing these vollies, his Rockets need not be more than three feet apart, it follows, that from an epaulement or battery of this description, fifty yards in length, he may keep up this bombardment by a discharge of fifty Rockets in a volley, and repeat these vollies every five minutes if desirable; a rate of firing which must inevitably baffle all attempts of the most active and numerous enemy to prevent its effect. It is obvious, therefore, that in any comparison made of the powers of the Rocket with those of common artillery, whether an officer be called on merely to demonstrate its powers, or to carry it actually against an enemy, the foregoing maxim must be his rule; in fact, every thing should be demonstrated according to the spirit of its use; a single Rocket is not to be compared with a single gun shot, by firing it at a target. But the consideration is, whether for general service, the power of quantity in the fire of Rockets does not _at least_ counterbalance the greater accuracy of the gun? and for this purpose the spirit of the demonstration of the Rocket system is to shew how few men are required to produce the most powerful vollies with this arm. No demonstration should be made with less than twenty rounds in a volley; to maintain which, in any fixed position, at the rate of two or even three vollies a minute, twenty men may be said to be sufficient, and this with Rockets projecting cohorn, or 5½-inch howitzer shells, or even 18 and 24-pounder solid shot. The first point of comparison, therefore, is--How many rounds of _such_ ammunition in the minute could twenty men project by the ordinary means of artillery?--or how many in a volley, even if they had all the means at hand?--And the next point is--what are the comparative facilities in bringing these different means into action, where the one system requires only the transport of the ammunition--the other, not only that of the ammunition, but of the most massive ordnance, without which it is entirely useless?