《明史·列传·卷一百三十七》
忽然从林中传来一阵喧哗声，数千人围着一个船形物，高一丈、长五十丈、高几层楼，两旁包着牛皮，放下木板就如同平地一般。
忽自林中大噪，数千人拥物如舟，高丈许，长五十丈，楼数重，牛革蔽左右，置板如平地。
Suddenly, there was a clamor from the forest. Thousands of people surrounded a boat-shaped object. It was thirty meters high and one hundred and fifty meters long, with several stories. It was covered with cowhide on both sides. When the wooden boards were lowered, it was as flat as the ground.