Topic: Militaria
Gun
From: The Military Guide for Young Officers, by Thomas Simes, Esq., Philadelphia, 1776

From: The Military Guide for Young Officers, by Thomas Simes, Esq., Philadelphia, 1776
Gun. The length is distinguished by three parts; the first reinforce, the second reinforce, and the chace; the first reinforce is two sevenths, and the second one-seventh and half a diameter of the first. The inside hollow, wherein the powder
and shot are lodged, the bore, and the diameter of the bore, is called the diameter of the caliber: the part between the hind end and the bore, the breech; and the fore part of the bore, the mouth. The cascable is the part terminated by the hind part of the breech, and the extremity of the button. The trunnions are the cylindric parts of metal which project on both sides of the gun, and rest in the grooves, made in the side-pieces of a carriage. The mouldings are those behind the breech, and reckoned to belong to the cascable, the first and second reinforce ogees, astragals, rings, and fillets. Those of the first reinforce are a ring ogee joining to it, and an astragal with fillets; the part of the gun between the ogee and astragal is called the vent field; because the vent is placed there; the ogee of the second, a ring and ogee; and those of the chace, a ring ogee; the astragal with fillets, the muzzle astragal; the swelling of the muzzle, an ogee or cimaise and two fillets: the part between the ogee and chace astragal, the chace girdle; and the part from the muzzle, astragal and the mouth, the muzzle. Formerly guns were distinguished by the names of sakers, culverins, cannon, demi-cannon, &c. at present their names are taken from the weight of their shot, as, for example, a twelve or twenty-four pounder carries a ball of twelve or twenty-four pounds weight.
Guns are made of brass or cast iron; the brass is a mixture of copper and tin; sometimes yellow brass is added, but it is reckoned to make the metal brittle. The most common proportion is, to an hundred pounds of copper, twelve pounds of tin; copper requires a red heat to melt, and tin melts in a common fire; when a gun is much heated by firing, the tin melts or softens so much that the copper alone supports the force of explosion, whereby they generally bend at the muzzle, and the vent widens so much as to render the gun useless. If such a composition could be found that required an equal degree of heat to melt, it would answer the intent; but as no such thing has been hitherto discovered, I look upon good iron to make better and more durable guns than any other composition whatever, as experiments and practice have shewn. All our brass battering guns made use of this last war, were too soon rendered unserviceable.
The necessary tools for loading and firing guns, are rammers, sponges, ladles, worms, hand- spikes, wedges, or screws. The rammer is a cylinder of wood, whose diameter and axis is equal to that of the shot, and serves to ram home the wads out upon powder and shot; the sponge is the same, only covered with lamb-skin, and serves to clean the gun when fired; the rammer and sponge are fixed to the same handle. The ladle serves to load the gun with loose powder; the worm to draw our the wads when a gun is to be unloaded; the hand=spikes, to move and lay the guns; and the coins, or wedges, to lay under the breech of the gun, to raise or depress it.
In field-pieces, a screw is used instead of coins, by which the gun is kept to the same elevation. The tools necessary to prove guns, besides those mentioned for loading, are, a priming-iron, a searcher with a reliever, and a searcher with one point. The first searcher is an iron, hollow at one end to receive a wooden handle; having on the other, from four to eight flat springs of about six inches long, pointed and turned outwards at the ends. The reliever is an iron flat ring, with a wooden handle at right angles to it. When a gun is to searched after it has been fired, this searcher is introduced, and turned every way from one end to the other; and if there is any hole, the point of one or the other spring gets into it, and remains till the reliever, passing round the handle of the searcher, presses the springs together and relieves it; if any of the points catch in the vent, the priming-iron is introduced to relieve it. When there is any hole or roughness in the gun, the distance from the mouth on the outside is marked with chalk. The other searcher
has also a wooden handle and a point at the fore end of about an inch long; at right angles to the length about this point is some wax mixed with tallow, and when introduced into the hole or cavity is pressed in, and drawn forwards and backwards; then the impression upon the wax gives the depth, and the length is known by the motion of the searcher if the hole is a quarter of an inch deep and downwards, the gun is rejected.
A gun when pointed to hit the mark, will carry the ball about seven hundred yards, the culverin about the same distance, but the bastard less. The ordinary force of a gun, fired at two hundred yards from the mark, drives the ball into the solid earth about ten or twelve feet; and into sand, or loose earth, from twenty two to twenty-four feet.
Parts of a Cast iron or Bronze Gun
Diagram from "An Introduction to British Artillery in North America," by S. James Gooding, Museum Restoration Service, Ottawa, Ontario, 1965.
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