to concentrate on his research. Outside of his university work, Jenkin held a number of appointments. He was Chairman of the Materials Subcommittee of the Aeronautical Research Committee, and was also Chairman of the structures investigation committee of the Building Research Board. Military service In May 1915, Jenkin was granted a temporary commission in the Royal Navy Volunteer Reserve in the rank of lieutenant. He worked in the Air Department of the Admiralty. On 5 October 1916, he was promoted to temporary lieutenant commander. On the amalgamation of the Royal Naval Air Service and the Royal Flying Corps in April 1918, he was appointed head of the branch of the Royal Air Force responsible for aircraft materials. He was granted the rank of lieutenant colonel and attached to the Ministry of Munitions. In 1918, the results of his research in this area were published as Report on Materials of Construction used in Aircraft and Aircraft Engines. On 31 March 1919, he was transferred to the unemployed list, thereby ending his military service. Later life Following his retirement from the University of Oxford, Jenkin moved to St Albans, Hertfordshire. He survived a series of heart attacks in 1933 but was left living in pain. He died on 23 August 1940 at his home in St Albans. His funeral and burial took place on 27 August 1940 at St Albans Abbey. Personal life In 1889, Jenkin married Mary Oswald Mackenzie, youngest daughter of the Scottish Judge Lord Mackenzie. Together they had two sons and a daughter. His was outlived by his wife and their daughter May. His younger son Conrad Jenkin (1894–1916) died while serving in the Royal Navy during World War I. His elder son Charles Oswald Frewen Jenkin (1890–1939) was an engineer. His grandchildren and great-grandchildren include Patrick Jenkin, Baron Jenkin of Roding, a cabinet minister and life peer, and Bernard Jenkin, a member of parliament. He was a self-taught multi-linguist: he spoke medieval French, medieval Spanish, Italian, Portuguese, and Catalan, in addition to his native English. Honours During World War I, at some time between May 1915 and March 1919, he was appointed Member of the Order of the British Empire (MBE). In the 1919 King's Birthday Honours, he was promoted to Commander of the Order of the British Empire (CBE) 'in recognition of distinguished services rendered during the war'. He was elected a Member of the Institution of