Educated at St George's Hospital, and practised at Wiveliscombe, Somerset, in partnership with Dr Andrew Francis Edwards. He was Surgeon to the Okehampton Slate Quarries, Wiveliscombe Slate Quarries, West Somerset Mineral Railway, Brendon Hills Iron Mines, to several clubs, and was Medical Referee to Assurance Societies. He was likewise for twelve years Surgeon to the Ebbw Vale Company's Ironworks, and was Medical Officer to the Dulverton and Williton Unions, District Vaccinator, and Surgeon to the West Somerset Volunteer Rifles. He removed to 68 Duke Street, Chelmsford, between 1866 and 1872, was Senior Medical Officer to the Chelmsford Infirmary and Dispensary, Medical Examiner and Referee for Essex to the Railway Passengers Assurance Company, and Medical Referee to several other Assurance Companies. After leaving Somersetshire he joined a number of medical societies, and was a Fellow of the Royal Medico-Chirurgical Society and the Obstetrical Society of London, a member of the Pathological Society, and Corresponding Member and Hon Local Secretary of the Harveian Society. By 1888 Nicholls had removed to Cornwall, first to Newquay (Trenarren), and later to St Columb (Trekenning House). He died on July 28th, 1917. Publications:- "Reminiscences of Cases in Private Practice." - *St George's Hosp Rep*, 1869, iv, 201. "Excision of the Ankle" in Holmes's *System of Surgery*, v. "Case of Rabies - Recovery." - *Lancet*, 1878, i, 862. Papers to various periodicals on naevus and its treatment and on tetanus.