Countless missionaries came to the building after the Association Mission Building was completed, and Henry G.C. Hallock was one of them. Hallock, with his unique personality, left a strong mark in Shanghai's religious history. 

In 1896, Hallock received a doctorate in philosophy and came to China as a missionary to travel around. He was proficient in seven foreign languages, but he completely gave up several other languages in order to better master Chinese. He published "Hallock’s Almanac” on the basis of the traditional Chinese almanac. In addition, he added some geographical facts, daily life skills, health tips, religious quotes, etc. This almanac was reader-friendly so that people with different levels of education could understand it. In 1905, because of being unwilling to follow others' advice, Hallock chose to become an independent missionary. In order to strive for more welfare for Chinese children, he often sent a large number of letters to various newspapers and organizations. In many cases, he doesn't even know the specific names of the mail receivers, hence replacing the actual names with ‘Dear curator’, ‘Dear chief editor’, etc. He was a typical ‘spam master’ in the era of mail.

Hallock was very popular then because of his maverick, optimistic and cheerful personality. He devoted his life to his missionary career and contributed to the rights of women and children in China by opposing women's footbinding and advocating women's right to education. Hallock’s story was just one of the many tales about the struggles of ordinary people in the Association Building.