Tan Qian is good at history. In view of the fact that the historical records of the Ming Dynasty have been broken by historians, Qubi has been sued, and most of them are secretive and inaccurate, and various chronicles are also rough and untrue. They tried to find all kinds of information, solicited information extensively, and made every effort to collect information. The first year of the apocalypse (162 1) was compiled, and the first draft was completed in six years. In the fourth year of Shunzhi (1647), the whole book was stolen and rewritten angrily, which lasted for more than 30 years and was compiled into a book "National Deficiency".