Born 4 March 1866, the son of John Turner Caddy, MD, MRCS (died 1902), deputy inspector-general of hospitals and fleets, Royal Navy, and Florence Thompson, his wife. Arnold Caddy's younger brother Adrian also became a Fellow of the College. He was educated at King's College School and St George's Hospital, and in Dublin, Leeds, and Paris. He served as house physician and house surgeon at the Royal Northern Hospital, and senior house surgeon at the Leeds General Infirmary under Arthur Mayo-Robson and Berkeley Moynihan, and was resident surgeon at the North Lonsdale Infirmary, Barrow in Furness Caddy took the Fellowship in the spring of 1891 and was appointed assistant surgeon at the Cancer Hospital, London. But he emigrated the next year, 1892, to Calcutta, where he went into partnership with William Coulter, MRCS (1848-1912), surgeon to the Marwari Hindu Hospital. He served as an officer in the Calcutta Light Horse. He married on 15 November 1902 a daughter of Archibald Currie of Melbourne, and in 1912 they settled at Chandpara, Tylden, Victoria, to farm. Caddy gave up the practice of surgery, and during the war of 1914-18 he was in command of a reinforcement camp with the rank of lieutenant- colonel, Victorian Light Horse. Caddy bred the bull, Chandpara Valentine, which became champion at the Royal Melbourne show. He served as a judge at the Chicago International livestock exposition, and became president of the Redpoll Cattle Association of Australia. Caddy died at Melbourne on 15 April 1948, aged 81, survived by his wife and two sons. His elder son, a colonel in the British army, was attached to the rocket-bomb installation in South Australia; his younger son, an officer in the Australian forces, was taken prisoner by the Japanese at Singapore in 1942 and forced to work on the notorious Bangkok railway and in coal mines in Japan, but survived. Publication:- *The transport of wounded*. 1916.