Born at Kotahena, Colombo, Ceylon on 30 July 1884, the eldest child of Francis Dionysius Alles, broker of Whittall and Co, and Mary Rodrigo Perumal his wife. His father's brother was a Roman Catholic priest well known in Ceylon, the Rev P M Alles, OMI. He was educated at St Joseph's College, Colombo and entered the Ceylon Medical College in 1902. In 1906 he won the Tyagaraja medal for his work in materia medica, took first place in the first class at the second professional examination, and was awarded the second professional scholarship. He graduated LMS Ceylon in 1908 and came to England where he studied at the Middlesex Hospital, took the Conjoint qualification in 1909 and the Fellowship in 1912, after serving as clinical assistant at the Central London Ophthalmic Hospital from 21 August to 21 November 1912, and returned at once to Ceylon, where he registered as a practitioner on 17 January 1913. On 3 March 1913 he was appointed house officer at the General Hospital, Colombo, and on 27 September house surgeon at the Victoria Memorial Eye Hospital. A year later, 1 October 1914, he was appointed lecturer in anatomy at Ceylon Medical College. At the General Hospital he was appointed fourth surgeon on 1 October 1920, raised to the first grade on 1 October 1922 and became third surgeon on 16 April 1931. At the time of his death, four years later, he was acting second surgeon at the hospital, and lecturer in surgery at the college. Alles married (1) on 2 April 1914 Julie Frances Massillamany, who died on 3 April 1926, leaving three sons and three daughters; and (2) his first wife's younger sister Mary Magdalene Massillamany, who survived him with a son and three daughters. He practised at MacCarthy Road, Colombo, where he died on 12 May 1935.