Cai Yong
Cai Yong, like Zhang Heng, was a prolific writer in addition to his mathematical, astronomical, and musical interests. In AD 159, Cai was summoned to Chang'an to perform on the Chinese zither for the imperial court, but became ill shortly before arriving and returned to his home. Cai composed a poetic record of his journey in ""Fu" on Recounting a Journey" ("Shù xíng fù" ), his most well-known "fu". In ""Fu" on Recounting a Journey", Cai cites examples of treacherous and dishonest rulers and officials from Chinese history, then criticizes the eunuchs of the capital for similar crimes.