Australian Dictionary of Biography

David Dewhurst, 1967

National Archives of Australia, A1200:L64268

David John Dewhurst (1919–1996), biophysicist and biomedical engineer, was born Alfred Irvine Nixon on 8 January 1919 at Inglewood, Victoria, youngest of four surviving children of locally born parents Alfred Nixon, farmer, and his wife Margaret Maria, née Irvine, formerly a schoolteacher. His mother died of a postpartum haemorrhage shortly after his birth and his father died two months later after falling and fracturing his neck. Adopted by his father’s cousin, John Heyliger Dewhurst, an Anglican vicar, and his wife Winifred Maude, née Tatchell, he was renamed David John. The Dewhursts subsequently adopted a daughter with whom David was raised in suburban Melbourne. The family spent a year in Britain in 1926–27.

As a child, David immersed himself in electronics in his workshop under the stairs. Educated at Malvern Church of England Grammar School (dux 1936), he intended to follow his adoptive father into the ministry and studied classics at the University of Melbourne (BA Hons, 1940). Possessing an extraordinary memory, he would pepper his conversation with classical and literary allusions and quotations for the rest of his life.

Army service in World War II drew on Dewhurst’s technical aptitude and led him to a different career. On 3 June 1940 he enlisted in the Australian Imperial Force and joined the Australian Corps of Signals. Arriving in the Middle East in March 1941, he served in Syria with the 2/2nd Anti-Aircraft Regiment (July-September) and then in North Africa with the 2/1st Air Support Control Signals. After being hospitalised with hepatitis A in December, he embarked for Australia with his unit in February 1942. He served in regiments of the 1st Anti-Aircraft Brigade in Sydney, Brisbane, and Townsville from June, and was appointed as an acting lieutenant in December (confirmed, 1943). In January 1945 he began a radio course and, on completion in May, was posted as an instructor at the Land Headquarters School of Signals, Bonegilla, Victoria. There he met Hilda Marjorie Wilmot, an army cipher officer, whom he married on 13 December 1949 at St Mary’s Church of England, Caulfield, Melbourne.

Demobilised on 24 January 1946, Dewhurst returned to the University of Melbourne (BSc, 1949; MSc, 1952; PhD, 1959) and studied physiology and electronics. While completing his master’s degree, he took over a small electrophysiology laboratory in the department of physiology. He was appointed a lecturer in 1952. Working on a shoestring budget, he transformed his unit into a renowned centre of medical instrumentation. He liked to quote the physicist Sir Ernest (Baron) Rutherford—‘We had no money so we had to think’ (Kirsner and McKenzie 2014, 10)—and he made excellent use of army surplus electronic equipment to build instrumentation for research, teaching, and clinical purposes. In 1959 he was awarded his doctorate for research into the biophysics of cell membranes, and in 1964 he was promoted to reader in biophysics (later biophysics and biomedical engineering).

Dewhurst’s laboratory supported an active research program into human muscle function, including intracellular recording and electromyography. It was a group within which ideas flourished. The purchase in 1966 of a PDP-8 minicomputer, the first in Australia, enabled the group to acquire and process electrical and mechanical physiological data in real time. Dewhurst became an expert programmer and passed his skills onto many others. From 1961 his influential course on medical electronics for biological researchers attracted senior clinicians and researchers. Pergamon Press published his course notes as a book, Physical Instrumentation in Medicine and Biology (1966, revised 1976).

A sabbatical year at Cambridge University in 1959 had ignited Dewhurst’s interest in medical and biological engineering. From 1965 he served on the administrative council of the International Federation for Medical and Biological Engineering (IFMBE) (president 1969–72; honorary life member, 1979). In 1971 he convened the 9th International Conference on Medical and Biological Engineering in Melbourne. Locally, his professional enthusiasm led to the formation of the Society for Medical and Biological Engineering (Victoria) in 1959, the Australian Federation of Medical and Biological Engineering in 1967, and the Institution of Biomedical Engineering (Australia) in 1974.

Dewhurst was intensely involved with measuring the electrical safety and performance of medical instrumentation. He was chairman of the electro-medical equipment committee of the Standards Association of Australia, which produced safety standards in the early 1970s. Later, as a member (1982–91) of the National Health Technology Advisory Panel, he played a significant role in the introduction to Australia of high technology medical techniques such as magnetic resonance imaging.

In 1975 Dewhurst’s laboratory moved to the department of electrical engineering. There he collaborated with Graeme Clark, professor of otolaryngology, in the development of the prototype multi-channel cochlear implant (the ‘bionic ear’), with graduate students working under his supervision on speech-processing software and electronic circuits for the implantable chip. His commitment to the needs of people with disabilities, inspired by his disabled son Peter (d. 1978), also found expression in FRED (Friendly Electronic Device), an interactive teaching device for the physically or mentally disabled which was conceived by Dewhurst in 1981.

From 1977 to 1988 Dewhurst wrote an idiosyncratic and much-read column, ‘On the Real Axis,’ in the IFMBE newsletter, with wide-ranging observations on biomedical engineering, its practice and ethics, and odd interpolations about wombats, bludgers, Omar Khayyam, steam engines, Horace, the plague, and more. In 1991 the IFMBE published a selection of his articles as a book. A colleague later recalled that reading the column conjured up ‘vivid images of the warm-hearted, cheerful, inventive, gently critical, and humour-loving Dave Dewhurst’ (McKenzie 1997, 53).

After retiring in 1985, Dewhurst moved with his wife to their holiday house at Portarlington, where he continued to work on FRED and other biomedical projects. He was appointed AM in 1990. Survived by his wife, their daughter and a son, he died at Wallington on 4 March 1996 and was cremated. That year the Biomedical College of Engineers Australia inaugurated the David Dewhurst award for biomedical engineering excellence.