Ship tradition

According to records, the sails of traditional ships in China are triangular. This sentence is wrong. Sailing in ancient China was a kind of equipment that used wind to drive ships, vehicles and water pumps.

As early as 2000 BC, China ships began to use sails. The characters (reading and writing) in Oracle Bone Inscriptions may be the original characters of the sail, and its image is two bamboo poles and a sail.

During the Three Kingdoms period, multiple sails were gradually adopted, including double sails, three sails, four sails and even seven sails. The sails are staggered to increase the wind area to improve the sail efficiency, and more sails and lower wind pressure centers can make the ship more stable. In the Song Dynasty, there was a spindle mast, which could be raised and lowered, so that sailboats could pass through bridge opening smoothly. In the Ming Dynasty, most wooden sailboats, mainly sand boats, were able to sail against the wind.

Thanks to the clever cooperation of sail, rudder and flash board, the boatman has the ability to sail in all directions. Waterboards, also known as waist rudders, are installed on both sides of the ship. When sailing against the wind, put the water boards on the downwind side into the water in order to reduce the yaw angle of the ship. Cloth sails are often used in North China, Central China and East China of China. Mat sails are also used in southern China.

Longitudinal sail is the characteristic of most wooden sailboats in China. In the Ming and Qing Dynasties, the vertical sail wind turbine in Yangzhou installed eight vertical sails on an octagonal wooden frame at equal intervals and rotated around a vertical axis, which could automatically adjust the angle of the sails. It is mainly used to extract seawater and make salt in coastal areas of China. In the Qing Dynasty, there was also a kind of sail-hanging unicycle that used both wind power and manpower.