Born in Malta, the son of the Rev John Keeling, a well-known Wesleyan minister at that time residing in the island. He returned to England with his family and was sent to the Wesleyan School at Woodhouse Grove, near Leeds. He entered the University of Edinburgh in 1848, and after graduating MD pursued his medical studies in London, Paris and Vienna. He became an assistant to George Bower Thorpe (qv), of Staveley, but on the outbreak of the Crimean War in 1854 he went out as Surgeon to the second regiment of the Turkish contingent. For his services he was awarded the decoration of Officer of the Order of the Medjidie. He returned to Staveley and in 1858 settled at Sheffield, acquiring the practice of Joseph Cheetham at Crow Tree House, Broomhall Street, then a country house in a big garden. He lived here with his sister till he removed in a few years' time to Glossop Road. In 1858, while at Staveley, he applied unsuccessfully for the post of House Surgeon at the then Sheffield General Infirmary. In 1860 he became Lecturer on Medical Jurisprudence at the Sheffield Medical School, and thus began "an association with the teaching of Medicine in Sheffield which lasted nearly forty years. When he accepted this office he made the stipulation that toxicology should be taught by a chemist, and Dr Allen accordingly undertook this part of the subject." In 1862 Keeling was elected Surgeon to the Public Hospital and Dispensary, now the Royal Hospital, Sheffield, and retained office for twenty-five years, when he became Consulting Surgeon. In 1864 Keeling was appointed Lecturer on Physiology in the Medical School, of which the affairs were then so far from satisfactory that it had been proposed to close it. Partly owing to his efforts it became possible to reconstruct the school in 1865. Resigning his physiology lectureship, he was then appointed Lecturer on Midwifery and the Diseases of Women in conjunction with Dr James H Aveling. He held this post for thirty-two years. Keeling, Aveling, and Edward Jackson were the first appointed Medical Officers of the Hospital for Women, founded in 1864. Later the Jessop Hospital for Women was erected through the generosity of Thomas Jessop. Keeling was deeply interested in this hospital, subscribing largely to its funds, and obtaining further substantial sums which were required for its extension in 1902. "The position attained by the Jessop Hospital as one of the leading medical charities of Sheffield was largely due to his efforts, and when he retired in 1906 the board elected him Honorary Consulting Medical Officer, and placed on record its high appreciation of his valuable and disinterested work. It was proposed to present him with a testimonial on this occasion on behalf of his colleagues, but he characteristically vetoed the gracious suggestion. "Reserved in disposition, Keeling delighted to do good by stealth and to labour for others in secret. It is recorded how at hospital meetings he was noted for the rebukes he administered to local orators who 'indulged in too much flattery about his own and other medical men's services' to the medical institutions. In a speech to the Jessop Hospital governors in 1898 he is reported to have said 'that doctors serve on the honorary staffs of hospitals simply and solely for the personal benefit they can derive thereby…that the patients also simply attend hospitals for what selfish benefit they can get, and that the rich keep up hospitals principally at the dictation of an enlightened self-interest which tells them that it is the best way of securing good doctors for themselves when ill, and in some small degree for the satisfaction, also selfish, which comes by being benevolent'. For all this seeming cynicism he was one of the most generous of men, and long after his official connection with the Medical School of Sheffield had ceased, he continued to take a keen interest in its welfare. It was he who under the veil of 'A Sheffield Citizen' equipped at a very considerable cost a new pathological department, and his contributions to the building and endowment fund of the University were most generous." He was the Hon Local Secretary in association with A Jackson at the Sheffield Meeting of the British Medical Association in 1876. He was for many years active in the work of the Sheffield Medical Society, and contributed many papers to it, though he does not appear to have published any. He was able, experienced, and well versed in the literature of his profession. He practised for a very long period at 267 Glossop Road, and, after some years of failing health, died there on March 14th or 15th, 1909.