Manuscript notes, papers and correspondence relating to the preparation of Cruickshank's paper: "Scientific method and Eddington's fundamental theory", Science Progress, no 140, Oct 1947 (his first published paper).
- Pencil and ink notes on various sizes of paper compiled at different times, contained within a spring binder.
- Correspondence: Institut International des Sciences Theoriques to Cruickshank in relation to the Eddington Prize (16 Nov 1948).
- Canon I T Ramsey to Cruickshank re Eddington paper (1 Feb 1948).
- Herbert ? (UCL) to Cruickshank re Eddington paper (22 Jan 1948).
- Sir Edmund Whittaker to Cruickshank (19 Jan 1948).
- Dr Martin Johnson to Cruickshank (3 Jan 1948).
- Dorothy Emmet (Manchester) to Cruickshank (15 Jan 1948).
- Sir Edmund Whittaker to Cruickshank (16 Jan 1948).