Born at Sydney, Australia on 27 September 1862, the eldest of four children and only son of the Rev William Johnstone and Margaret King, his wife, who lived to be 100, he grew up in New Zealand where his father was Presbyterian minister at Port Chalmers, and was educated at Otago Boys High School, Dunedin, graduated in arts at the University and began his medical studies at the Otago Medical School. Coming home to Scotland, he qualified with honours in medicine, surgery and public health, and won the George Thomson travelling fellowship at Aberdeen University. This enabled him to make postgraduate studies at Berlin, Munich, Vienna, and Paris. After serving as house surgeon at the Royal Infirmary, Glasgow, he was clinical assistant and pathologist there under Sir William Macewen. He then came to London, took the Fellowship in 1891, and settled in general practice at Richmond, Surrey, where his career was spent, first at 26 Sheen Road and later at Tudor House, King's Road. He was for a time pathologist to the London Homeopathic Hospital and served on the Council of the British Homeopathic Society. Besides building up a large and successful practice during forty-five years, Johnstone took a leading part in local affairs. He served on the education committee of the borough council, was chairman of the juvenile employment committee, and was a founder of the local Council of Social Service. He lectured in medicine at the Wesleyan College, Richmond. He was an active freemason, a member of the Richmond lodge, and past assistant grand director of ceremonies in the Grand Lodge of England, and past standard bearer of supreme grand chapter; he was a member of the old Richmond Lodge of Harmony, and compiled its history; he was also a member of the Quatuor Coronati Lodge, and was at work on the history of freemasonry in his last years. He was a founder-member of the Richmond Rotary Club, and its second president. He was a keen amateur of botany, geology, and archaeology, was active in preserving local historical monuments, and took a prominent share in the cultural activities of the Richmond Athenaeum. He became a magistrate in 1932. He married in 1892 Ethel Rose Hudson, who was created MBE for her work at home and in France in the war of 1914-18. Mrs Johnstone died in April 1952 two days before their diamond wedding; she had been a borough councillor at Richmond. He died in the West London Hospital on 14 February 1953, aged 90, survived by four sons and a daughter. Publication: Transfusion subcutaneous and intravenous in gynaecological practice, with George Burford. *J Obstet Gynaec Brit Emp* 1905, 7, 445.