John was educated at the United Services College, from 1890 - 1895 and St Mary's Hospital, London, qualifying M.R.C.S., L.R.C.P. in 1906. He served in the ranks (Private) in the Medical Staff Rodesian Field Force, S Africa from 1900-1901. He gained a commission within the R.A.M.C. at the rank of Lieutenant on 28th January 1907, and was promoted to Captain on 28th July 1910. He served in India from 1909 until war was declared, when he returned to the UK and proceeded to France in September 1914. John served in France until 1915, he also served in Mesopotamia from 1915 - 1916 and 1921 - 1922 - during this time, on 28th January 1919, he was promoted to Major. He served again in India, from 1922 - 1926 [invalided] and 1928 - 1934, and during this time served under the rank of temporary Lieutenant Colonel, from 25th January 1931 and Lieutenant Colonel from 15th April 1931. John retired on pay on 15th March 1934 and was taken off the Regular Army Reserve of Officers on 26th May 1936. Due to the outbreak of World War Two, John rejoined on 1st September 1939. He served as Commanding Officer at the Military Hospital, Shorcliffe until 1940, under the rank of acting Colonel from 9th October 1939, and temporary Colonel from 9th April to 26th August 1940. On 27th August 1940 he reverted back to retired pay, but was re-employed again with the rank of Major on 8th October 1940. John finally retired on 16th August 1945 and was restored to Lieutenant Colonel (Honorary Colonel]. He was by then a specialist in Entomology. John died at Birchingham, Kent. He was the son of Surgeon Lieutenant Colonel H. Boyd. [Information sources: The Medical Officers in the British Army 1660 - 1960; MIC and John's family]