Born on 10 September 1869, he was educated at Cheltenham College and Durham University. He graduated MB BS in 1891 and afterwards held a series of resident appointments in Newcastle. He was a demonstrator of anatomy and lecturer in surgical anatomy in the old University of Durham Medical College. In 1905 he was appointed assistant surgeon to the old Infirmary, and in 1920 surgeon to the new Royal Victoria Infirmary, retiring as consultant surgeon in 1929; he then was appointed surgical director of the Newcastle General Hospital. He had been County Controller of Northumberland VAD since 1921, and was Vice-President of the Section of Urology at the Annual Meeting of the BMA in 1921, and during 1934-35 was chairman of its Newcastle Division. Clay served in South Africa 1900-02 as a surgeon lieutenant in the RAMC, and in 1914-18 in France and Belgium, first as commanding officer of a CCS and later as ADMS of the 50th Northumbrian Division. He was a full Colonel, an honorary surgeon to the King, and was awarded the CBE (military division). John Clay contributed many articles to the journals, and wrote the section on surgical anatomy in the 1919 edition of *Gray's Anatomy*. A skilled anatomist, he was a scrupulous surgeon particularly interested in urology, and one of the first to introduce the use of the cystoscope in the North. He was married with a daughter and sons, one of whom, a doctor, was killed in a motoring accident. Clay died on 6 July 1962 at 6 Victoria Square, Newcastle-on-Tyne.