[196]
round, the borer forms the bore of the gun, which complains loudly of this treatment; for it makes a screaming noise, that may be sometimes heard to the distance of two miles. During this operation of boring, the workman turns and finishes the outside of the gun, by sharp-edged pieces of steel applied to its sides; and the ornamental parts of it, cyphers, or crown, with the projecting part which holds the priming, are done by the hand with a hammer and chissel; the touch-hole is then drilled, and the gun compleated. An eighteen-pounder, nine feet long, when compleat, without its carriage, weighs 42oolbs.; one of eight feet, two tons; a twenty-four pounder 5000lbs.; and a thirty-two pounder 5500lbs. weight.
The method of casting cannon-balls is as follows: two pieces of iron, like two basons, are placed upon each other, with a groove turned in the lower, so that the upper fits upon it. Hie inside of each is turned, and hollowed like a half-sphere, so as to fit exactly; and in tlus operation great nicety is required. In the centre of one of these pieces a hole is bored, to admit the melted iron, and nothing more is required than to place these pieces upon each other, dusting them with a little powdered charcoal or black lead, and then to pour the melted metal into the hole till it is full.
