Traditional Culture Encyclopedia - Almanac inquiry - Who first invented the perpetual calendar?

Who first invented the perpetual calendar?

Ten thousand years.

For example, starting from 19 16, Zheng Zhenxiu decided to create a "perpetual calendar" in view of the great waste of manpower and material resources caused by changing calendar cards every year. Finally, in 1936, he created a perpetual calendar, which consisted of a dial, a watch core and a watch case, starting in one year BC and ending in 9999. This innovation attracted the attention of the Canadian government and granted him a 50-year patent.