Practical breach, is that where men may mount, and make a lodgment, and should be 15 or 20 feet wide.
Capital of a work, is an imaginary line which divides that work into two equal parts.
Capital of a bastion, a line drawn from the angle of the polygon to the point of the bastion, or from the point of the bastion to the centre of the gorge. These capitals are from 35 to 40 toises in length, from the point of the bastion to the place where the two demi-gorges meet; being the difference between the exterior and the interior radii.
Caponnier is a passage made in a dry ditch from one work to another: when it is made from the curtain of the body of the place to the opposite ravelin, or from the front of a horn or crown-work, it has a parapet on each side, of 6 or 7 feet high, sloping in a glacis of 10 or 12 toises on the outside to the bottom of the ditch; the width within is from 20 to 25 feet, with a banquette on each side: there is a brick wall to support the earth within which only reaches within 1¹⁄₂ foot of the top, to prevent grazing shot from driving the splinters amongst the defendants.
Caponnieres with two parapets may properly be called double; as there are some made with one rampart only, in dry ditches of the ravelin, and in that of its redoubt, towards the saliant angles, and to open towards the body of the place.
Caponnieres, made from the body of the place to the out-works, are sometimes arched over, with loop-holes to fire into the ditch. The single ones in the ditch of the ravelin and redoubt are likewise made with arches open towards the place; for by making them in this manner, the guns which defend the ditch before them, can no other way be dismounted than by mines.
Cascanes, in fortification, a kind of cellars made under the capital of a fortification; also subterraneous passages or galleries to discover the enemy’s mines.
Casemate, in fortification, is a work made under the rampart, like a cellar or cave with loop-holes to place guns in it.
Cavaliers, are works, raised generally within the body of the place, 10 or 12 feet higher than the rest of the works. Their most common situation is within the bastion, and they are made much in the same form: they are sometimes placed in their gorges, or on the middle of the curtain, and then are in the form of a horse-shoe, only flatter.
The use of cavaliers is, to command all the adjacent works and country round them: they are seldom or never made, but when there is a hill or rising ground which overlooks some of the works.