How did Hai Zhangwu get rich?

Hai Zhangwu made a fortune by selling salt. Hairen, whose real name is Linqing, was a big official. Zhang Jinwen used to be a waiter in Linqing kitchen. During the Jiaqing period, Zhang Jinwen went to the famous salt merchant's office in Shuixizhuang, Tianjin, and gradually became familiar with salt affairs. Later, he became a rich man in Tianjin by salt affairs. Hai Zhangwu, whose real name is Zhang Jinwen, is from Liu Du Town, Jinghai. Although Zhang Jinwen is a rich man in Tianjin, he was born at the grassroots level. His early family was poor. He lost his father in childhood and begged for a living with his mother. Recommended by his uncle, he was regarded as an adopted son by Hai Ren, director of the Ministry of War, ranking fifth. His nickname "Hai Zhangwu" came from this. In Tianjin, there are many stories about Hai Zhangwu. Jin, a landscape expert in Tianjin, said that during the Second Opium War, the British and French allied forces captured Dagukou Fort. Entrusted by the government and people from all walks of life, Hai Zhangwu mediated between the government and the Allies, reached an agreement with the Allies, and set up a "support bureau" to supply a batch of property and military supplies to the Allies by the people, on the condition that the Allies were not allowed to disembark and were prohibited from going out to burn, kill and plunder.