Siheollyeok (Almanac)

The Siheon (or Shixian) Calendar is a lunisolar calendar developed in Qing on the basis of the Western calendar system. Unlike the older calendar in which the twenty-four solar terms are evenly arranged according to the method of "balancing energy" with the Winter Solstice as the starting point, this newer calendar uses the method of "fixing energy," whereby the Yellow Path is divided into 24 equal segments of 15 degrees. This new method was introduced to Joseon in 1646 by Gim Yuk (1580-1658), resulting in the use of a new calendar in 1653. This particular item was made by the Directorate of Astronomy in 1730.