The 60-volume Mei Series is an astronomical and mathematical work by great mathematicians in the early Qing Dynasty. Among them, there are 40 volumes of mathematical works 13, including 6 volumes of Equation Theory (1672), 2 volumes of Calculation (1678), 5 volumes of Outline of Flat Triangle (1684) and Outline of Arc Triangle. There are five volumes of pen calculation (1693), five volumes of millet ruler in the ring (1700), two volumes of block measurement, one volume of Fiona Fang's power product theory (17 10), and two volumes of degree calculation and explanation examples (.