Professor William Valentine Mayneord, FRS
Val Mayneord started his first job in medical physics, at St Bart's Hospital, London, in 1924, at the age of 22. That was, of course, a time when radiotherapy was in its infancy; there was almost no scientific basis for radiation dosimetry, artificial radioisotopes and pulse-echo ultrasound were still 20 odd years in the future, and the concept of radiation protection was almost unheard of. Within 30 years all that had changed; medical physics had achieved much of its present-day structure, character and rigour; and, although many individuals had contributed to this development and much useful ground work had previously been laid by people like C E S Phillips, a remarkable proportion of the intellectual leadership and sheer physical hard work behind it was that of Mayneord. Indeed, any modern medical physicist with an interest in the origin of his or her subject is warmly recommended to read Mayneord's official biography (1), which is one of the most lively and illuminating brief histories of medical physics that has been written. In the 1920's radiotherapy was largely based on surgical implantation of radium needles and, at Bart's, Mayneord worked with Geoffrey Keynes, a pioneering surgeon and brother of Maynard, the economist, who in his autobiography described how, in this work, surgeons such as himself had to put themselves "completely in the hands of the physicist". His firsthand experience at that time of the sometimes appalling radiation injuries to both patients and staff made a deep impression on him and, very soon after his move, in 1927, to the Cancer Hospital (now Royal Marsden) he started making major contributions to the modern subject of radiation dosimetry. He had a major hand in making the case for an ionization method for the measurement of X-ray dose, and hence in defining and establishing the Röntgen and subsequently in the move towards absorbed dose and the rad. It was also he at that time who introduced the concept, that was to become central to radiation protection, of integral dose. It was once remarked that the Röntgen was the quantity that we could measure but did not want, the rad was what we wanted but could not measure, whilst kerma was neither wanted nor measurable. That may have been an overstatement but certainly, when in 1960 Mayneord first heard that this new radiological quantity was being introduced without his having been involved, he remarked to a colleague that it was surely time for him to retire! However, retirement was still a long way off when the Second World War broke out and when, immediately after it, Val was seconded by the Government to a year's consultancy in Canada in connection with the radiobiological aspects of atomic energy development. He returned from this to London, according to a colleague "brimming with new ideas, both technically and in relation to the scope of physics in medicine. In particular he saw that the work had to be broadened to take advantage of all the new developments in electronics and to exploit the exciting medical possibilities of nuclear physics". Thus, within a few years, his department was reporting pioneering work, and the first outside the U.S.A., both in diagnostic ultrasound and in nuclear medicine, including construction of one of the world's first radioisotope scanners - preceding the g -gamma camera by some 10 years. As another practical response to the nuclear age, Mayneord established, in the 1950's, a major research programme that made a substantial (and, importantly at that stage, academically independent and objective) documentation of man's natural and artificial radiation environment. This was, in a sense, a practical expression of his long-standing interest in radiation carcinogenesis and it was to the more philosophical and theoretical aspects of this complex subject that his attentions returned during a long and active "retirement", leading in particular to publication of a "Biomathematical Reconnaissance" of the subject, which has become a classic in the field (2). Perhaps even more important than his own personal scientific achievements was his building up of an internationally renowned department of "physics as applied to medicine" (he never like the term Medical Physics, believing as he did that physics is one entity, fundamental and indivisible!). He achieved this, partly by having the vision to see that good medicine must be based on good science and that good physical scientists need a strong and stimulating environment in which to thrive, and partly by a personality that somehow inspired loyalty, friendship and respect in just the right proportions. For those who had the good fortune to work with him he was an inspiring teacher, sometimes a hard task master, but always a sensitive, supportive, and very human colleague and friend. References 1. Spiers F.W. (1991), William Valentine Mayneord, in Biographical Memoirs of The Royal Society, 37, 341-364. 2. Mayneord W.V. and Clarke R.H. (1975) Carcinogenesis and radiation risk: a biomathematical reconnaissance. Brit. J. Radiol. Supplement 12.