[1][2] Watson was appointed assistant surgeon in the Bombay army medical service in August 1850.
He served with the artillery at Ahmednagar and with the Scinde horse at Khangarh (Jacobabad), and was then appointed assistant surgeon to the Jamsetjee Hospital and lecturer on physiology at Grant Medical College.
[1] Returning to England on sick leave in 1853, Watson spent some time at the School of Mines in London's Jermyn Street.
[1] Foster retired from the India Office in 1880, and died at Upper Norwood on 29 July 1892.
He also drew up catalogues for the Indian departments at international exhibitions, and with John William Kaye edited Meadows Taylor's People of India, London, 1868–1872, 6 vols.
Numerous photographs were made in depicting India, and large maps of the country in relief.