Traverses are likewise made within other works, when there are any hills or rising grounds from whence the interior parts of these works may be observed. Traverses that are made to cover the entrances of redoubts in the field, need not be above 8 or 10 feet thick.
Trous-de-loup, or wolf holes, round holes made about 5 or 6 feet deep, with a stake in the middle: they are generally dug round a field redoubt, to obstruct the enemy’s approach; circular at top, and about 4¹⁄₂ feet diameter; pointed at the bottom like an inverted cone. Two or three rows of them are dug chequerwise, about 6 paces from the edge of the ditch, viz. two rows of holes exactly opposite to each other, and a third row in the middle, covering the intervals.
Wicket, a small door in the gate of a fortified place, at which a man on foot may go in, and which may be opened though the gate itself be kept shut.
Works. All the fortifications about a place, are called the works of a place.
Out-works. All detached works in a fortification are so called. See [Dehors].
Zig-Zag. See [Siege].
The principal maxims of fortification, are these, viz. 1. That every part of the works be seen and defended by other parts, so that an enemy cannot lodge any where without being exposed to the fire of the place.
2. A fortress should command all places round it: and therefore all the out works should be lower than the body of the place.
3. The works farthest from the centre should always be open to those that are nearer.
4. The defence of every part should always be within the reach of musquet shot, that is, from 120 to 150 fathoms, so as to be defended both by ordnance and small fire arms; for if it be only defended by cannon, the enemy may dismount them by the superiority of their’s, and then the defence will be destroyed at once; whereas, if a work is likewise defended by small arms, if the one be destroyed, the other will still subsist.