In the course of his studies of French, like a number of other notable recruits to phonetics of that generation including A. C. Gimson and J. D. O’Connor, he attended Daniel Jones’s flourishing Department of Phonetics for tuition in French phonetics by the redoubtable Hélène Coustenoble. That experience no doubt inspired his choice of career. He was invalided out of the armed forces when in Egypt in 1942 he lost a leg. He then spent a year acquiring an education diploma at Cambridge but very soon after that was taken onto the staff of SOAS with which he stayed for the rest of his working life.
He was naturally considerably influenced by his contacts there with J. R. Firth. Towards the end of the forties he began studies on various African languages which led to his making a series of visits to Nigeria and other locations in Africa which bore fruit in various important studies on phonetic, phonological and other aspects of Hausa and several other, mainly west African, languages. He was awarded a chair of phonetics in 1972. In 1991 admiring colleagues brought out a festschrift in his honour in the form of a volume in the series York Papers in Linguistics.
On his retirement in 1982 he had returned to live in the county of his birth but kept in touch with colleagues not least by his attendance until the late nineties at the biennial gatherings of the British Association of Academic Phoneticians. He was a convivial man and a great talker. Many will remember that a much enjoyed feature of the dinner held at each of those gatherings was Jack’s invariably requested recital of a highly amusing parody of biblical genealogies applied to well known figures of the linguistics community.