Complex sentence: Having then lived for two years in Surrey, followed by seven in Scotland Hay came to London, where on 10 December 1839 he took up an appointment as the first Inspecting Superintendent of the Metropolitan Police.
Split into simpler sentences: Having then lived for two years in Surrey, followed by seven in Scotland. Hay then came to London, where on 10 December 1839 he took up an appointment as the first inspecting superintendent of the Metropolitan Police.