《论衡·卷六·祸虚篇》
起自临洮，直到辽东，筑长城，挖沟渠，经过一万里，这中间不可能不断绝地脉。
夫起临洮属之辽东，城径万里，此其中不能毋绝地脉。
From Lintao to Liaodong, building the Great Wall and digging canals, spanning ten thousand miles, it is impossible not to have cut off the earth's energy.