Zhou Da (1879 ~ 1949) was born in Zhide County (now dongzhi county). When he was young, he had a close relationship with China and often asked China for advice. When I was just twenty years old, I finished the book Seeking Pythagoras Integer (one of "Counting Grass in Shangzhi Bookstore") and sent it to China for review. Soon, I finished writing four volumes of Triangle Harmony and Comparison, and sent them to China and Huawei for preface. What is particularly important is the establishment of "Zhixin Computing Society" in Yangzhou, and Zhou Da was promoted as the president of the society, which is the earliest folk mathematics group in China. /kloc-in the winter of 0/902, Zhou Da was entrusted by Zhixin Computing Co., Ltd. to travel to Japan, and gained a lot. After returning to China, he wrote a book "Investigation on Mathematics in Japan", which was published by lithography in the 29th year of Guangxu (1903). Two years later, he went to the East again to discuss math problems with his Japanese counterparts. 1930, Mingfu Library affiliated to China Science Society was completed. Among them, there is a special room to collect more than 10 thousand dollars donated by Zhou Da, which is named "American Rights Library". He has made great achievements in the field of stamp collecting, and enjoys the reputation of "the king of postal services" in China.