13]
25. What is the dispart of a piece?
It is the difference of the semi-diameter of the base-ring and the swell of the muzzle, or the muzzle-band. It is, therefore, the tangent of the natural angle of sight to a radius equal to the distance from the rear of the base-ring to the highest point of the swell of the muzzle, or the front of the muzzle-band, as the case may be, measured parallel to the axis.
26. Give the nomenclature of a piece?
The CASCABLE is the part of the gun in rear of the base-ring, and is composed generally of the knob, the neck, the fillet, and the base of the breech.
The BASE OF THE BREECH is a frustum of a cone, or a spherical segment in rear of the breech.
The BASE-RING is a projecting band of metal adjoining the base of the breech, and connected with the body of the gun by a concave moulding.
The BREECH is the mass of solid metal behind the bottom of the bore, extending to the rear of the base-ring.
The REINFORCE is the thickest part of the body of the gun, in front of the breech; if there be more than one reinforce, that which is next the breech is called the first reinforce; the other the second reinforce.
The REINFORCE BAND is at the junction of the first and second reinforces in the heavy howitzers and columbiads.