rideau

A judgment may be formed of the weakness of the place, either by the facility found in making the approaches, or by establishing the magazines in the rear of the trenches, taking advantage of some rideau, or hollow way, whereby the right and left of the trenches are better supported. In order to judge of the facility of making the approaches, observe whether there are in the neighbourhood of the place any ditches, hollow ways, rideaus, houses, hedges, behind which the enemy may advance, and place their guards of horse and foot under cover from the fire of the place ; …