Zhang Heng, courtesy name Pingzi, formerly romanized Chang Heng, was a Chinese polymathic scientist and statesman who lived during the Eastern Han dynasty. Educated in the capital cities of Luoyang and Chang'an, he achieved success as an astronomer, mathematician, seismologist, hydraulic engineer, inventor, geographer, cartographer, ethnographer, artist, poet, philosopher, politician, and literary scholar. 78 – 139; died at about 60. Alive at the same time as Marcus Aurelius, Plutarch, John the Apostle, Apuleius, and Ptolemy. Wiki link