2, "Historical Records" Volume 30 has: Zhi Jian Ship, more than ten feet high, with a flag on it, very strong. The main feature of shipbuilding in Han dynasty is that it has multi-storey superstructure. The shape of the ship in Han dynasty is: under the deck is the cabin for paddling; The soldiers on the deck are in close combat with swords, and a half-high protective wall is set on the side of the ship, which is called Wenlou.
The biography of Sui Shu Yang Su recorded that he lived in Yong 'an and built a big ship named Infinite. Five floors up, six cypress poles are placed in front and back, which can accommodate 800 soldiers. Five-tooth ship is 54.6m long, with a width of 15m, a deck width of 16m, a depth of 4m, and a draft of 2.2m Ships refer to military and civilian ships.