In honor of Zhang's achievements in science and technological know-how, his Good friend Cui Ziyu (Cui Yuan) wrote a memorial inscription on his burial stele, that has been preserved while in the Guwen yuan.[8] Cui said, "[Zhang Heng's] mathematical computations fatigued (the riddles of) the heavens along with the earth. https://heng36520975.blogdal.com/32075406/new-step-by-step-map-for-heng365