《墨子·56章 备梯》
行城和杂楼之间要保持适当的距离，两者之间的部分要拉上防护用的遮幕，因此距度不宜过宽。
以适广陕为度，环中藉幕，毋广其处。
The distance between the "moving city" and the "miscellaneous building" should be moderate, and the parts between them should be draped with protective curtains, so the distance should not be too wide.