[ATOMIC BOMB]: COCKCROFT JOHN (1897-1967) British physicist, Nobel Prize winner for Physics 1951 in recognition of splitting the atomic nucleus. During World War II Cockcroft served as Assistant Director of Scientific Research in the Ministry of Supply, working on radar, and was also a member of the committee formed following the Frisch-Peieris memorandum which calculated that an atomic bomb could be technically feasible. Cockcroft was also part of the Tizard Mission of 1940 and was also later instrumental in the development of nuclear power. Manuscript D.S., J D Cockcroft, one page, 4to, n.p., 27^th April 1949. Cockcroft responds to a researcher's questionnaire entitled World Inquiry, with their manuscript questions at the head of the page, '1. Were your scientific “debut” easy or difficult? 2. Did means of living…..enable you to make yourself known in science? Or did you live solely through your work of laboratory? 3. What work (or what discovery) made yourself more famous? Which do you consider as your masterpiece?'. Cockcroft provides his answers beneath, in full, '1. Difficult. 2. Yes - to some extent. 3. Disintegration of atoms by artificial means 1932', adding his signature below. Some very light, extremely minor age wear and one minor, neat split to the lower edge, otherwise VG