《史记·八书·天官书》
若欲自初一占卜到十二日，卜法又有不同，每日与月相对应，占卜水旱灾情。
数至十二日，日直其月，占水旱。
If we want to foretell from the first day to the twelfth day, the divination method is different. Every day corresponds to the phase of the moon, foretelling the disaster of flood or drought.