Characteristically active to the end, Robert Ditchburn collapsed as he arrived at King’s College London (KQC), for a meeting of the British Pugwash Group on 8 April, and died shortly afterwards. His interests and influence extended widely beyond his own fields of research in physics, diverse though these were, and he wrote of him self: ‘if I could have had equal health, wealth and opportunity for scientific work I would have liked to live in an earlier period when it was possible to range over wide areas of science.... My work has been less specialized than that of most of my contemporaries but still more specialized than I would have liked.’ His main fields of research were, in fact, the following: (i) the photo-ionization of gases and vapours, (ii) other absorption processes relevant to the upper atmosphere, (iii) the optical properties of solids, especially diamonds, and (iv) the effect of eye movements on visual perception. Included in this list is what he will be especially remembered for, the development and application of methods for stabilizing images on the retina. But perhaps his main contribution to the advancement of science— this was his own judgement— was his work in building the Department of Physics in the University of Reading: the J. J. Thomson Physical Laboratory. He was proud to have been among the last research students of J. J. in the Cavendish, and he succeeded in having the new building in Whiteknights Park named after him. He himself had been appointed professor and head of the department in 1946, succeeding J. A. Crowther. He retired from the chair and headship in 1968. He was succeeded in the chair by the author of the present memoir, and in the headship by E. W. J. Mitchell, at that time Professor of the Physical Properties of Materials at Reading, now C.B.E., F.R.S., and Chairm an of SERC. Robert Ditchburn continued his work on eye movements after his retirement, working in the Department of Engineering at Reading (which, in 1968, was part of the Department of Applied Physical Sciences), and carrying forward a long collaboration with J. A. Foley- Fisher. His second book
Eye movements and visual perception
, was published during this period. He took advantage of his greater freedom to pursue his wider interests: he continued his work as a consultant to the diamond industry, and he devoted much time to the Pugwash Movement — this he considered to be his most worthwhile activity after his retirement. It was fitting that his last hours should have been spent in going about its business.
Academic relationships between Hungarian professors and the Second Vienna Medical School
