Born on 25 March 1874 the son of James Greenwood Slater, he was educated at Bradford Grammar School and Trinity College, Cambridge, where he graduated with first-class honours in the Natural Sciences Tripos part I, 1895. He qualified in 1898, having trained at the Middlesex. In 1898 he became house physician and house surgeon at the Middlesex Hospital, and from 1900 to 1905 he was assistant surgeon at the Bradford Royal Infirmary. He was Medical Superintendent at the Bradford Poor Law Hospital until the war of 1914-18. During the war he was commissioned a Major RAMC and served at Gallipoli, Egypt, and Salonika, and was later Officer-in-Charge of the Surgical Division, 38th General Hospital. After the war he returned to the Bradford Poor Law Hospital as Medical Superintendent, and in 1921 he became Senior Surgeon at the Bradford Municipal General Hospital. He was also medical adviser to the Scarborough Disablement Advice Committee and Medical Referee to the Ministry of Labour and National Service. In later years he was honorary consultant surgeon at St Luke's Hospital, Bradford. He married Dr Ella Beales, and lived at St Mary's, Lastingham, York. He died in or before February 1959.