the military art, an engine or fire-arm for throwing iron, lead, or stone bullets, by force of gunpowder.

Cannons at first were called bombardz, from the noise they made. They had likewise the name of culverin, basilisk, &c. from the beasts that were represented upon them; and the Spaniards, from devotion, gave them the name of saints; witness the twelve apostles which Charles V. ordered to be cast at Malaga, for his expedition to Tunis.

The metal of which cannons are composed, is either iron, or which is more usual, a mixture of copper, tin, and brass; the tin being added to the copper, per, to make the metal more dense and compact; so that the better and heavier the copper is, the less tin is required. Some to an hundred pounds of copper, add ten of tin, and eight of brass; others ten of tin, five of brass, and ten of lead. The Sieur Bereau pretends, that when old pieces of metal are used, the founder ought to add to one hundred weight of that metal, twenty-five pounds of good copper, and five pounds of tin. Braudius describes a method of making cannon of leather; and it is certain the Swedes made use of such in the long war of the last century; but these burnt too easily to have much effect. With regard to iron cannon, they are not capable of so much resistance as those of brass; but as they are less expensive, they are often used on board of ships, and also in several fortified places.

Cannons are distinguished by the diameters of the balls they carry. The rule for their length is, that it be such as that the whole charge of powder be on fire, before the ball quit the piece. If it be too long, the quantity of air to be drawn out before the ball, will give too much resistance to the impulse; and that impulse ceasing, the friction of the ball against the surface of the piece will take off from the motion.

In former days, cannon were made much longer than they are now; but experience has taught us, that a ball moves with a greater impetus through a less space than a greater; and accordingly it is found, that an iron ball of forty-eight pound weight goes farther from a short cannon, than another ball of ninety-six pound out of a longer piece; whereas, in other respects, it is certain, the larger the bore and ball, the greater the range.

It is found too, by experience, that of two cannons of equal bore, but different lengths, the longer requires a greater charge of powder than the shorter. The ordinary charge of a cannon is, for the weight of its gun-powder to be half that of its ball.

We shall here subjoin a table exhibiting the names of the several cannon, their length, their weight, and that of their ball.

| Names of cannon | weight of an iron ball | weight of the cannon | length of the cannon | |--------------------------|------------------------|---------------------|---------------------| | Cannon royal | 48 0 | 8000 | 12 0 | | Demi cannon large | 36 0 | 6000 | 12 0 | | Demi cannon ordinary | 32 0 | 5600 | 12 0 | | Demi cannon least | 30 0 | 5400 | 11 0 | | Culverin largest | 20 0 | 4800 | 12 0 | | Culverin ordinary | 17 5 | 4500 | 12 0 | | Culverin least | 15 0 | 4000 | 11 0 | | Demi culverin ordinary | 10 11 | 2700 | 11 0 | | Demi culverin least | 9 0 | 2000 | 10 0 | | Saker ordinary | 6 0 | 1500 | 10 0 | | Saker least | 4 12 | 1400 | 8 0 | | Minion largest | 3 12 | 1000 | 8 0 | | Minion ordinary | 3 4 | 800 | 7 0 | | Falcon | 2 8 | 750 | 6 0 | | Falconet | 1 5 | 400 | 5 6 | | Rabinet | 0 8 | 300 | 5 6 | | Base | 0 5 | 200 | 4 6 |

Cannon are likewise distinguished according to the diameter of their mouth, or calibre. This calibre is divided, in consequence of an order from the king of France, into thirty-six parts, in order to determine by these parts the dimensions of the different moulds for cannon. We hope the reader, then, will not be dissatisfied to find an account of the dimensions of the several parts of cannon of five different calibres, as they are regulated by that order of the king of France, on Oct. 7, 1732, in the following table:

| Pieces of cannon | of 24 | of 16 | of 12 | of 8 | of 4 | |------------------|-------|-------|-------|------|------| | feet. | inch. | feet. | inch. | feet. | inch. | | Length of the bore | 9 6 | 9 2 | 8 8 | 7 10 | 6 6 | | Depth of the chamber | 2 6 | 1 10 | | | | | Thickness of metal at breech | 5 5 | 4 9 | 4 4 | 3 9 | 3 | | Length of the cascabel | 10 11 | 9 6 | 8 8 | 7 7 | 6 | | Diameter of the trunions | 5 5 | 4 9 | 4 4 | 3 10 | 3 | | Projection of the trunions | 5 5 | 4 9 | 4 4 | 3 10 | 3 | | Calibre of the piece | 5 8 | 4 11 | 4 6 | 3 11 | 3 2 | | Diameter of the ball | 5 6 | 4 9 | 4 4 | 3 9 | 3 | | Length of the whole piece | 11 | 10 6 | 10 | 8 10 | 7 3 | | Weight of the piece | 5400 | 4200 | 2200 | 2100 | 1150 lb. |

Vol. II. No. 31. Cannon, with letter-founders and printers, the name of the largest size of the letters they use.