《墨子·52章 备城门》
连着城墙修筑令耳，令耳是两重的楼房。在城墙外堞下凿穴，深一丈五尺，宽一丈二尺。
令耳属城，为再重楼，下凿城外堞，内深丈五，广丈二。
Build a order house connected to the city wall, the order house is a two-story building. Make holes in the crenels outside the city wall, one foot and five inches deep and one foot and two inches wide.