Born at Kensington on 19 October 1852, the younger of the two sons of John Harrison, FRCS 1844, surgeon major, Grenadier Guards, a Waterloo veteran, and Sophia his wife, daughter of Captain John Lugard, 6th Inniskilling Dragoons. He was thus a first-cousin of Sir Frederick John Dealtry Lugard, PC, GCMG, DSO, 1st Lord Lugard of Abinger, sometime Governor-General of Nigeria. He was educated at Wellington College, St Bartholomew's Hospital, and the Army Medical School, Netley, where he won the Sidney Herbert prize for taking first place in both the entrance and final examinations. Harrison's father died in 1873. In January 1874 he qualified, and was commissioned a surgeon in the Army Medical Service on 30 September 1874. On 10 March 1875 he was posted to the Grenadier Guards, with which his father had served from 1809 to 1840. He saw active service with the regiment in Egypt in 1882, and was in the action at Mahuta and at the battle of Tel-el-Kebir, winning the medal with clasp and the bronze star. He was promoted surgeon major, Grenadier Guards on 19 August 1885 and brigade surgeon, lieutenant-colonel, Brigade of Foot Guards, on 4 November 1891. From 23 June 1898 under a Royal Warrant of that date he was borne on the strength of the Royal Army Medical Corps as a seconded lieutenant-colonel, until under a Royal Warrant of 4 January 1899 he reverted to his former post, the last to hold the brigade-surgeoncy. He was promoted brevet colonel (infantry) on 13 March 1907. From 1905 to 1909 he was the first commandant of Queen Alexandra's Military Hospital, Millbank, and was an honorary surgeon to King Edward VII from 1907 to 1909, when he was created CVO. He retired on 19 October 1909, one hundred years after his father had joined the Grenadier Guards. Harrison served in the RAMC Territorial Force from 1909 to 1918 and in the Territorial Reserve 1918-23. He commanded the 1st London General Hospital (TF) 1909-12 and was ADMS, 2nd London Division T.F., 1912. During the first world war he served in France in command of No. 23 General Hospital, Chicago Medical Unit 1915-16, was mentioned in despatches and created CMG 1916. From 1916 to 1918 he was in command of the Prince of Wales Convalescent Officers Hospital at the Great Central Hotel, Marylebone; and was deputy commissioner of medical services at the Ministry of National Service 1918-20. Colonel Harrison lived after retirement at 19 Westgate Terrace, Redcliffe Square, London, SW10, with his sister Miss Marian Harrison, who died on 1 June 1932, aged 82; he never married. In 1941, during the German air-raids on London, he was bombed out of his house and went to live with his nieces, May, Beatrice, Monica, and Margaret Harrison, well-known as cellist and violinists, daughters of his only brother, Colonel J H C Harrison, RE. Here at Woolborough Farm, Outwood, near Redhill, Surrey, he died on 25 January 1944, aged 91. He was the senior Fellow of the Royal College, and it was 100 years since his father's election as a Fellow. His life and his father's covered 156 years. He was buried at Outwood with full military honours; Major-General O W McSheehy, DSO, OBE, MRCS, represented the Director-General AMS, and the Grenadier Guards sent an escort of pallbearers and buglers. A memorial service was held at St Luke's Church, Redcliffe Square, SW, on 28 January.