Note:  Do not rely on this information. It is very old.

Breaching Tower

Breaching Tower, in the Middle Ages, the English name for the French beffroi, a movable tower of wood, covered with leather and mounted on four wheels, containing six or seven storeys. A battering ram was sometimes mounted on one of the lower storeys, while the upper contained slingers and archers to cover its advance or prevent defence of the wall. Froissart describes such towers, which were a legacy from the classical period.