Part 149

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.

Centre, the middle point of any work. From the centre of a place are drawn the first lines to lay down the form of a fortification.

Centre of the bastion, is that point where the two adjacent curtains produced intersect each other.

Citadel, is a kind of fort, or small fortification, of 4, 5, or 6 sides; sometimes joined to towns, &c. Citadels are always built on the most advantageous ground. They are fortified towards the city, and towards the country; being divided from the former by an esplanade, or open place: and serving in one case to overawe the inhabitants; and in the other, not only to hinder the approach of an enemy; but to become a retreat to the garrison, should the town be taken.

Coffers. See COFFERS.

Command is when a hill or rising ground overlooks any of the works of a fortification, and is within reach of common shot; such a hill is said to command that work. See COMMAND.

Complement of the curtain, is that part of the interior side which forms the demi-gorge.

Complement of the line of defence, is a horn-work with a crown-work before it. See CROWN-WORK.

Cordon, in fortification, is a round projection made of stone, in a semi-circular form, whose diameter is about 1 foot, and goes quite round the wall, and within 4 feet from the upper part.

The cordon being placed on the top of the revetement of the scarp, is a considerable obstacle to the besiegers, when they attempt to storm a place by applying scaling ladders to the scarp.

Covert-way is a space of five or six toises broad, extending round the counterscarp of the ditch, and covered by a parapet from six to seven feet and a half high, having a banquette: the superior part of this parapet forms a gentle slope towards the country, which terminates at the distance of twenty to twenty five toises; this slope is called the glacis.

Sometimes the covert-way is sunk 2 or 3 feet below the horizon of the field; for, as such works are never made to discover the enemy in their trenches, so this method of lowering the covert-way will give room for the fire of the lower curtain (in works that have one) to scour the esplanade; and the expence of it should be the most material objection against it.

Counter-forts, in fortification, are by some called buttresses; they are solids of masonry, built behind walls, and joined to them at 18 feet distance from the centre to centre, in order to strengthen them, especially when they sustain a rampart or terrace.

Counter-guard, in fortification is a work placed before the bastions to cover the opposite flanks from being seen from the covert way. It is likewise made before the ravelins.

When counter-guards are placed before the collateral bastions, they are esteemed of very great use, as the enemy cannot batter them without having first secured the possession of the counter-guards. They were first invented by Pasino, in 1579, and greatly improved by Speckle, in 1589.

Counterscarp, is properly the exterior talus of the ditch, or that slope which terminates its breadth, and is the further side from the body of the place. It is so called from being opposite to the scarp.

Crown-work, in fortification is a kind of work not unlike a crown: it has 2 fronts and 2 branches. The fronts are composed of 2 half bastions and 1 whole one: they are made before the curtain or the bastion, and generally serve to enclose some buildings which cannot be brought within the body of the place, or to cover the town-gates, or else to occupy a spot of ground which might be advantageous to an enemy. They are of such an expence, that they are rarely found in practice. The best use this work can possibly be put to, is to cover 2 joining curtains, when the sides of it will be parallel to the sides of the place, and it should be fortified with the same strength, and in the same manner.

The authors who have written on the subject, have never thought of this useful part; and we often see 2 horn-works put in practice to cover two curtains, where crown-work would do it much cheaper and much better. The crown-work is adopted for the same purposes as the horn-work.

Crowned horn-work, is a horn-work with a crown-work before it. See CROWN-WORK.

Curtain, in fortification, is that part of the body of the place, which joins the flank of one bastion to that of another. The straight curtains have always been preferred to the different designs which have been proposed, of which some have diminished the expence, and (at the same time) the strength of the place, others have somewhat augmented the strength, but greatly diminished its area.

Cuvette, Cunette, in fortification, is a small ditch from 15 to 20 feet broad, made in the middle of a large dry ditch, serving as a retrenchment to defend the same, or otherwise to let water into it, when it can be had during a siege.