The Ophthalmic Hospital was later called the Boji Hospital. Kerr opened a Vaccine Department at the hospital in 1859, offering free smallpox vaccinations to Cantonese children. Kerr also published informational pamphlets on the importance of vaccinations. The Medical Missionary Society's Hospital was located on the Pearl River on Yan-tsai Street in Canton. It included 10 buildings and 300 patient beds. The hospital was managed and funded by the Medical Missionary Society.. Parker opened the Medical Missionary Society's Hospital in 1839 and was succeeded by John Kerr as physician in charge. Kerr retired from the Canton Hospital in 1899 to devote his time to caring for the mentally ill. In China, it was public custom to treat for the person as a whole, including mental syndromes. The most common treatments in 19th century China included: shackles, fetters, herb medicines, acupuncture, toxin liquid therapy, and magic words or formulas. In 1872, Kerr appealed to the Medical Missionary Society to build a mental hospital in China. Between 1876 and 1880, Kerr campaigned for the necessary and rightful treatment of patients with mental illnesses in their own, designated hospitals. Kerr believed in treating and curing the mentally ill rather than isolating them from society. However, neither the city government or the Canton Medical Missionary Society wanted to fund a mental hospital. Kerr used his own money to purchase 17 acres in Fangcun (southwestern Canton) as a building site for the hospital. With donors and assistance, two buildings were erected . He attended to 50 patients at the hospital before his deathref name=":1" />  In Canton, Kerr performed around 48,918 surgeries; his specialty being lithotomy and lithotrity, the removal of gallstones from the urinary tract, bladder or kidney. He performed surgery on both civilians and officials throughout the Guangxi Province. The Canton Hospital was one of the first hospitals in China to practice preventive hygienic measures such as separation, disinfection, and sterilization. Kerr helped to introduce these modern techniques during his surgeries and strived for his hospital to be a model of cleanliness for the Cantonese not only in the hospital, but in their private lives as well. There were separate rooms for patients with contagious diseases and the patient's clothes and utensils were sterilized, along with the operating room itself. In 1875, Kerr published "Weisheng yaozhi" (Essentials to Hygiene) which highlighted the priority of preventing illnesses through good hygiene.