Anthony John Clark, Ph.D.

Tony Clark was born on 22 March 1930 in Guildford. His early enthusiasm for archaeology was such that he was allowed to join the Surrey Archaeological Society as a minor in 1945, three years before its minimum age of eighteen. He had no formal training in the subject, his first job being in the laboratories of the instrument section of the Distillers Company, but his enthusiasm never waned. His reading included the first edition of Richard Atkinson's Field Archaeology (1946) with its prophetic concluding Note to Appendix III in which the author mentions his experiments in measuring the resistance of the soil to the passage of an electric current, a technique applied successfully in civil engineering but hitherto unknown in archaeology. In 1948 Clark's national service was spent at the Inter-Service Photographic Interpretation School at R.A.F. Nuneham Park, only three miles from Atkinson's rescue excavation of the Neolithic site, Big Rings, Dorchester-on-Thames, at which Clark was able to study the resistivity work. Atkinson had applied a Megger Earth Tester in his preliminary survey of the site and his methods were fully reported in the second edition of Field Archaeology (1953), by which time Clark's own experiments in geophysical prospecting were well under way. Atkinson's technique remained the sole instrumental method for detecting archaeological sites for some twelve years until the development of the transistor in the 1950s, an electronic advance with great potential for geoprospection, which Clark was quick to recognize. In collaboration with John Martin, a colleague at Distillers, Clark produced the highly complex but low-consumption Martin-Clark resistivity meter in 1956. The instrument was put severely to the test in the following year when Clark conducted a resistivity survey of the Roman town Cunetio, near Marborough, newly discovered from the air by J. K. S. St Joseph, and was readily able to detect the massive foundations of the town wall. By 1960 the Martin-Clark resistivity meter was available commercially and the prototype is now in the Science Museum. In 1967 Clark joined the Geophysics Section, newly established by John Musty, at the Ancient Monuments Laboratory of the then Ministry of Works as the first full-time professional archaeological geophysicist in Britain, and remained there until retirement in 1988. While working in the field, carrying out many of the now classic surveys which have laid the foundation of the subject in this country, Clark continued his study of the theoretical principles of the resistivity method and was awarded a doctorate from Southampton University in 1988 for this research. Arising from his sampling of kilns, hearth and ditch silts, he published, also in 1988, jointly with colleagues at the University of Newcastle-upon-Tyne, an archaeomagnetic calibration curve, essential for the conversion of magnetic readings of samples of clay into corresponding years. The computer processing of resistivity data was another of Clark's innovations in this country, following the work of Irwin Scollar at the Rheinisches Landesmuseum in Bonn in 1958, as was the use of magnetometer-type equipment for detecting buried kiln remains through the magnetic properties of the soil. In retirement he worked as a private consultant, setting up an archaeomagnetic dating facility, and wrote his book, Seeing Beneath the Soil (1990), dedicated to his mentor, Richard Atkinson, and reissued in an enlarged international edition in 1996. Clark was Honorary Secretary of the Royal Archaeological Institute from 1981-5 and a Visiting Fellow of Surrey University, where he supervised successive Ph.D.students. He was a member of the Antiquaries' Council in 1976 and a familiar figure in the apartments during his English Heritage days, always self-effacing, friendly and helpful, generous with his time and knowledge. In 1996 with the onset of illness, Clark decided to call it a day and donated his archaeomagnetic dating equipment to the Museum of London where his work will be continued in the Clark Laboratory, named after him, which houses this equipment. Only a few weeks before his death, when he was too ill to deliver a promised lecture to scientists at Surrey University, Clark attended the lecture which was read in his name by one of his former students, and enjoyed participating in the ensuing discussion and signing copies of his book. He died on 3 June 1997.