Anthony Clark contributed much to archaeological science, but will be remembered particularly as a pioneer in the use of geophysical prospecting methods which are now indispensable to much practical field archaeology.
By means of fieldwork and example he demonstrated the archaeological potential of a series of novel instrumental techniques which now form the basis of a small industry. He did this with a directness and originality which he would have been pleased to see as part of a worthy British tradition of underfunded scientific ingenuity, but also brought to his work the methods and awareness of a skilled field archaeologist.
Clark was conscious of following in the tradition of such notable earlier archaeological fieldworkers as I.D. Margary and O.G.S. Crawford, with their emphasis on the continuity and significance of each detail of the landscape, and he wished to extend their methods by introducing new sources of evidence. His archaeological career began when he was a precocious schoolboy excavator, and continued when he managed to turn even the experience of National Service to relevant effect. He trained in aerial photographic interpretation with the RAF at Nuneham Park in Oxfordshire, and heard during this improbably military interlude of the early experiments with resistivity surveying which Professor Richard Atkinson used to detect ploughed-out barrow ditches from 1946 onwards at Dorchester-on-Thames nearby. This encounter made a lasting impression and in 1956 Clark, together with a colleague also employed at the instrumentation laboratory of the Distillers' Company, developed the Martin Clark resistivity meter. This was a lightweight device specifically intended for archaeological work, the prototype of which later found a place in the Science Museum. Clark devoted much effort in subsequent years to experiments investigating the complex climatic and seasonal influences on the resistivity response from a variety of archaeological features, and this work later formed the basis of the thesis for which he was awarded a PhD by Southampton University in 1980. In 1967 Tony Clark was appointed to be the country's first full-time specialist in archaeological geophysics at the Ancient Monuments Laboratory, which formed part of the Inspectorate of Ancient Monuments at the then Ministry of Public Buildings and Works. Archaeological prospecting requires intensive ground coverage to detect the minute physical traces of past human activity, and so remains a laborious pursuit. Clark found this to be particularly the case in his single-handed early days, but he at length built up a team which continues as part of English Heritage today. From the late 1960s, magnetometer surveying, which had previously been investigated at the Oxford Archaeology Laboratory and elsewhere, became a more practical option following the development of a new and more portable magnetometer in response to police requirements for ground searching equipment. Clark was responsible for a series of classic demonstrations of the value of this device, which he applied with characteristic directness. He walked across Hampshire watching a flickering dial, and thereby added significantly to the archaeological record along the line of the proposed M3. By similar methods, combined with an interpretative boldness which few of his colleagues would have cared to match, he identified the campfire sites of the original builders behind the ramparts of an unfinished Surrey hillfort, and with an elegant economy of method he sorted a number of Hampshire hillforts in the course of a day into occupied settlements and uninhabited refuges. …