Abstract:

“Zhongxin”(center of gravity )and “xingxin”(center of figure) are two Chinese terms in science. The former appeared in Giulio Alenio’s Zhifang waiji(The World Geography,1623),and the latter appeared in Johann Schreck’s Qiqi tushuo(Description of Mechanical Instruments,1627).Both words are from Latin, which are the loan-translations of centrum gravitatis and centro figure(or geometrica centrum). The word “zhongxin” was later passed to Japan. However, the term “xingxin” has not been used for more than 300 years after the Qiqi tushuo. Later we saw this word again in a vocabulary of mathematical terms in 1935. However, it is not certain whether it is the use of the word in Qiqi tushuo, or it was later coined separately.

Key words: center of gravity, center of figure, centroid, center of mass