After the war, Merton directed an industrial research institute, worked as a venture capitalist and served as the chairman of the merchant bank Robert Fleming & Co. between 1974 and 1980.
[1] He initially planned to join the English Bar as a lawyer, and was called to the Inner Temple in 1944, though he ultimately chose a career in science and finance instead.
[2] During World War II, Merton worked as a researcher with the Admiralty and RAF, analysing the performance of pilots and developing optimum strategies for air defence, anti-submarine warfare and aerial bombardment.
[2][1] After discovering that the depth charges used by British anti-submarine aircraft often detonated too deep to destroy German U-boats, Merton and his fellow researchers developed an improved bombsight for naval bombers.
[2] In 1950, Merton joined the Erlangers banking house in the City of London, and assisted it in raising capital for numerous ventures, including a company that processed seaweed into industrial fibre.