chat or chatchasteil) was a movable pent-house used to protect besiegers when approaching a wall or gateway, for the purpose of sapping, mining or direct attack, or to cover a ram or other battering-engine.
By this time the besiegers were sapping under the escarps of the northern forts, and it would have been better to delay.
As the parliament of 1886 was drawing to a close, the dissensions among the Irish members, and the loss of their great leader, were visibly sapping the strength of the Nationalists.
His smile reassured her, sapping the ire and replacing it with peace.