78-139

Chinese Astronomer and Mathematician

Zhang Heng was a Chinese mathematician and scientist, born in the first century A.D.In addition to being one of the emperor's astrologers, Heng made a number of interesting astronomical discoveries. However, his most important invention was the seismograph, used to detect earthquakes at a great distance.

Virtually nothing is known of Heng's early life or, indeed, of his nonprofessional life. What is known is that he was a multitalented scientist who became a minister in the Chinese government during the rule of Emperor An'ti. During this time, he was the chief astrologer as well as a respected mathematician and scientist.

Heng is known to have made a number of important contributions during his life. As an astronomer, he made a very good attempt to bring some order to the stars, describing the sky as being composed of "124 groups which...