Part 152

Lunettes in fortification, are works made on both sides of a ravelin: one of their faces is perpendicular to half or ²⁄₃ds of the faces of the ravelin, and the other nearly so to those of the bastion.

There are likewise lunettes, whose faces are drawn perpendicular to those of the ravelin, within ¹⁄₃ part from the saliant angle; whose semi-gorges are only 20 fathoms.

These kind of works make a good defence, and are of no great expence; for as they are so near the ravelin, the communication with it is very easy, and one cannot well be maintained till they are all three taken.

Lunettes, are also works made beyond the second ditch, opposite to the places of arms: they differ from the ravelins only in their situation.

Lunettons, are small lunettes.

Merlon, is that part of the breast-work of a battery which is between the embrasures.

Orillon, is a part of the bastion near the shoulder, which serves to cover the retired flank from being seen obliquely: it is sometimes faced with stone, on the shoulder of a casemated bastion, to cover the cannon of the retired flank, and hinder them from being dismounted by the enemy’s cannon.

Of all the works in a fortification, there is none more capable of defending the passage of the ditch, and to destroy the miner, wheresoever he enters himself, than the orillon. Experience in the last war has shewn us of what vast advantage it is to have 2 or 3 reserve pieces of cannon, which command the ditch, and the face of the opposite bastion, in such a manner as to destroy the attempts of the miners, and see the breach in reverse. Hence the great advantages of a double flank thus concealed weigh so very much with us, and convince us so entirely of their usefulness, that we affirm no place to be well fortified without the orillon, and that the straight flank is fit for nothing but field works.

The orillon is as old as the bastion, and was first made use of about the year 1480; and we find it frequently mentioned in the works of Pasino and Speckle, first published in 1579.

Out-works. See WORKS.

Palisades, in fortification, are a kind of stakes made of strong spars about 9 feet long, fixed 3 deep in the ground, in rows about 6 inches asunder: they are placed in the covert-way, at 3 feet from, and parallel to the parapet of the glacis, to secure it from being surprised.

Parapet, in fortification, is a part of the rampart of a work, 18 to 20 feet broad, and raised 6 or 7 feet above the rest of the rampart: it serves to cover the troops placed there to defend the work against the fire of the enemy.

Parallels. See SIEGE.

Port-cullice, in fortification, is a falling gate or door, like a harrow, hung over the gates of fortified places, and let down to keep out the enemy.

Place is the term commonly used in fortification instead of a fortified town.

Regular place, one whose angles, sides, bastion, and other parts are equal, &c.

Irregular place, one whose sides and angles are unequal, &c.

Place of arms, in fortification, is a part of the covert-way, opposite to the re-entering angle of the counterscarp, projecting outward in an angle. It is generally 20 fathoms from the re-entering angle of the ditch on both sides, and the faces are found by describing a radius of 25 fathoms.

Places of arms. See SIEGE.

Pits, or ponds, in fortification, are little holes dug between the higher and lower curtains, to hold water, in order to prevent the passing from the tenailles to the flanks.

Profiles, in fortification, are a representation of the vertical sections of a work; and serve to shew those dimensions which cannot be described in plans, and are yet necessary in the building of a fortification; they may be very well executed and constructed upon a scale of 30 feet to an inch. By a profile are expressed the several heights, widths, and thicknesses, such as they would appear were the works cut down perpendicularly from the top to the bottom. See PROFILES.

Rampart, is an elevation of earth raised along the faces of any work, 10 or 15 feet high, to cover the inner part of that work against the fire of an enemy: its breadth differs according to the several systems upon which it may be constructed: for De Ville makes them 12¹⁄₂ fathoms, M. Vauban 6, and others 10 fathoms.

Rams-horns, in fortification, are a kind of low work made in the ditch, of a circular arc; they were first invented by Mr. Belidor, and serve instead of tenailles.

Ravelin, in fortification, is a work placed before the curtain to cover it, and prevent the flanks from being discovered sideways, it consists of 2 faces meeting in an outward angle. Some ravelins are counter-guarded, which renders them as serviceable as either the cunettes, or tenaillons.

Gorge of the ravelin, is the distance between the two sides or faces towards the place.

Gorges, of all other outworks, are the intervals or spaces which lie between their several wings or sides towards the main ditch. See GORGES.

Redans, in fortification, are a sort of indented works, consisting of lines or facings that form sallying or re-entering angles, flanking one another, and are generally used on the sides of a river running through a garrisoned town. They were used before bastions. Sometimes the parapet of the covert-way is carried on in this manner.

Redoubt, is a kind of work placed beyond the glacis, and is of various forms. Its parapet, not being intended to resist cannon, is only 8 or 9 feet thick, with 2 or 3 banquettes. The length of the sides may be from 10 to 20 fathoms.