《淮南子·人间训》
你如果不信的话，让我登上城楼击鼓，这时铠甲兵器和粮食就会马上齐备。 
君以为不然，臣请升城鼓之，甲兵粟米，可立具也。 
If you don't believe me, let me go up to the tower and beat the drum. At this time, the armor, weapons, and food will be ready immediately.