Jachi tonggam (Comprehensive Mirror for Aid in Government, Zizhi tongjian in Chinese) is a book on the general history of China compiled by Sima Guang of the Song Dynasty. It includes Volumes 236 through 238 out of 294 volumes. Scholars, such as Yun Hoe (1380-1436) and Kwon Je (1387-1445), made corrections and added annotations to the Chinese original in 1436 (the 18th year of King Sejong’s reign). Printed using Gabinja, a metal type made in 1434, this is an important material for research on the printing technology of the early Joseon Period.