Collection documents Mendelssohn's work at the Clarendon Laboratory, University of Oxford, from 1933 onward where he was the first person to liquefy helium in Britain and contributed to the establishment of the Clarendon as an important center of low temperature research; his work on collaborative projects in medical physics during World War II; his post-war supervision of gifted research students at the Clarendon, many of whom went on to build up graduate schools of their own in developing countries; and his involvement with low temperature scientists at the international level as a founder and chair of the International Cryogenic Engineering Committee and founder and editor of the journal, Cryogenics. In addition to correspondence and scientific notebooks, the papers include lectures, broadcasts, drafts, and publications on low temperature physics and other topics including his "extra-mural" interests: the scientific and cultural development of China and the sociological and engineering background of the Egyptian and Mexican pyramids. Also contains biographical and personal material and photographs.
