No. XXXI.
A way how safely and speedily to make an approach to a castle or town-wall, and over the very ditch, at noon-day.
NOTE.
A wheel carriage, of sufficient strength to support an heavy iron tower, must first be provided. It may be constructed of thick wrought iron, with door, &c., of the same material, and hung round with sand-bags, through the interstices of which may project from six to eight small guns to protect it from musquetry. The most eligible method of moving the tower appears to be by fixing small handles to the axles of the wheels, which may be turned at pleasure by those within the walls. To prevent any attempt of the enemy who may sally forth to drag the machine within the walls of the town, &c., it will be adviseable to arm the wheels with long steel studs, which, when the handles are fastened within, will render it immoveable.
This tower, though but of little use in modern warfare, appears well adapted for reconnoitring the walls of a fortified town, and, if fixed upon a hollow iron vessel, will possess the further advantage of crossing rivers and moats. Nearly similar machines are described by Vitruvius, and other authors who treat on military engineering.