The Development of Knowledge on Levers in Ancient China

Abstract

The lever is the simplest yet the most basic mechanical device. It was used in many ancient cultures around the world, each of which developed their machine-making technology and mechanical knowledge based on its own culture and tradition. A thorough study of the process and characteristics of the development of knowledge concerning levers may help to gain insight into the influences of cultures on technology. In China, in the book Mozi (墨子) from the the 5th to 4th century BC., a theoretical discussion about the function of lever was given. A chapter in the book Zhuangzi (the 4th – 3rd century BC.) revealed that in the 3rd century BC., a swape, called Jiegao (桔槔) in Chinese, was already commonly used for water-lifting. In later texts, devices with levers as the main components, such as a device to raise signal fire or trebuchet, were generally named Jiegao. There were written records that Chinese had developed complicated devices using levers by the 11th century. In this paper, based on extensive evidences, including archaeological excavation, paintings, philosophical and historical works, the development of the knowledge of levers of practitioners and academics in ancient China was analysed. The viewpoints on the characteristics of ancient Chinese lever technology were also presented and compared with that of Greece.