General Zhu Geliang, was ordered by a jealous commander to produce 100,000 arrows in ten days for his army, a seemingly impossible task. However, Zhu devised a plan to trick the enemy into supplying the arrows. Since the opposing fleets were moored on opposite sides of the Yangzi River, Zhu sheathed his ships in straw bales and on a foggy day sailed out as if for battle. The enemy responded by shooting thousands of arrows into the straw bales. Once Zhu's armory was sufficiently replenished, his fleet returned to port.

Source: Asia Society, The Teaching Company "From Yao to Mao" Lecture 7