Born at Wakefield on 12 April 1863, the third child and second son of Thomas Walker, MRCS 1848, and Elizabeth Jackson Seeker, his wife. His elder brother, John William Walker, MRCS 1882, was elected FRCS in 1941 and lived till 1953. The Walkers had practised medicine at Wakefield for two hundred years. H S Walker was educated at Wakefield Grammar School, Leeds Medical School, then part of the Yorkshire College, and at University College Hospital, London. After serving as house surgeon at Durham County Hospital, he settled as an eye and ear specialist at Leeds, and was appointed in 1890 assistant surgeon to the eye, ear, nose, and throat department of the General Infirmary. After six months study at Vienna, he introduced the mastoidectomy operation at Leeds. When the eye and ear departments were divided in 1912 he was appointed ophthalmic surgeon to the Infirmary. He was also lecturer in ophthalmology and otology at Leeds University. He attended "Ranji", the Jam Sahib of Nawanagar, after serious eye-injury in a grouse-shooting accident in 1914. The Prince, in gratitude for his recovery, named a ward after Seeker Walker in his hospital at Nawanagar, and also endowed a new ophthalmic theatre and out-patient department at the Leeds Infirmary. Walker's architectural ingenuity found scope in the creation of the new buildings of the Infirmary. Walker was commissioned in the RAMC on the formation of the territorial force in 1908, and during the war of 1914-18 he carried out the work of the eye departments of the East Leeds and Beckett Park Military Hospitals, with the rank of major. He was made consulting ophthalmic surgeon to the Infirmary when he retired in 1919, and then settled in Wiltshire. Here he served on the committee of the Bath Eye Infirmary, was pensions secretary of the Wiltshire Association of the Blind, and was the moving spirit and chairman till 1939 of the foundation committee of the Bradford-on-Avon District Hospital, which he saw opened in September 1947. Walker married in 1902 Elaine Mary Secker. He died on 18 February 1948, aged 84, at Fair Field House, Bradford-on-Avon, and was buried at Great Chalfield. He was survived by his son and two daughters. He was a man of cheerful disposition, and alert and precise mind. His manual dexterity as an operator was also displayed in his carpentry. Publications: Sarcoma of iris. *Trans Ophthal Soc UK*, 1895, 15, 814. Cysticercus of conjunctiva. *Ibid* 1896, 16, 47. Tumour of optic nerve. *Ibid*, p 139. Cerebellar abscess complicating mastoid disease. *Brit med J* 1895, 1, 806. A case of mastoid disease accompanied by septic thrombosis of lateral sinus and post-pharyngeal abscess, with retention of some hearing power. *Trans Otol Soc* 1901, 2, 126. A diagrammatic model intended to assist in the teaching of ocular refraction. *Trans Ophthal Soc UK* 1901, 21, 142. A model to illustrate the passage of rays of light through the eye in the various forms of astigmatism. *Ibid* 1905, 25, 307.