F.N. Dimock Brown was a licentiate of the Royal College of Physicians of London, and a member of the Royal College of Surgeons of England. He resided in Estcourt, Natal, for some time before 1897. From 1898 to at least 1900 he was associated with Hilton College, a well-known English medium school for boys near Pietermaritzburg. He joined the South African Philosophical Society in 1897 and was still a member in 1900.
In 1897 Brown collected some plants in Natal. Specimens from Karkloof and Port Shepstone are in the Natal Herbarium. He was also interested in other aspects of natural history, for during 1898 he consulted the insect collection of the South African Museum in Cape Town.