Includes several letters written from the University of Rochester, New York, where Martin was Visiting Professor, 1936-37. Correspondence is mainly re research and Imperial College affairs. Some of the exchanges are conducted with A. Rankine or H. Dingle, in Thomson's absence from Imperial College.
Included are letters from Stanley Baldwin (B/67), Lady Betty Balfour (B/70), Harley Granville Barker (B/69), Sir J. M. Barrie (B/68), Edmund Charles Blunden (B/71), Evelyn Boscawen, 8th Viscount Falmouth (B/71), Robert Strutt, 4th Baron Rayleigh (B/67), Max Planck (B/67, B/70), Sir J. H. Jeans (B/71), Sir W. H. Bragg, (B/73), Godfrey Benson, 1st Baron Charnwood (B/67), Prince Chula of Siam (B/72), W. Martin Conway, 1st Baron Conway of Allington (B/71, B/73), Sir G. H. Duckworth (B/68), Frederich Homes Dudden (B/66), Lilly Frazer (B/72), Violet Grimston, Countess of Verulam (B/73), Graeme Haldane (B/72), Roy Harrod (B/72), A. E. Housman (B/73), David A. E. Lindsay, 27th Earl of Crawford (B/70), Sir Henry McCardie (B/63), Margaret (Daisy) McTaggart (B/68, B/70), Victoria Mountbatten, Marchioness of Milford Haven (B/70), Katharine, Lady Parsons (B/66), Marga Planck (B/67), A.O. Rankine (B/73), John, 1st Viscount Sankey (B/72), Lady Marjorie Sinclair, Baroness Pentland (B/71), Lady Elisabeth Babington Smith (B/66, B/69), Lucy Babington Smith (B/69), Susan Babington Smith (B/69), John Bulloch Souter (B/73), Angela Thirkell (B/72), Mari M. Thompson (B/73), Sir Henry Francis Wilson (B/68), F. Theodore Woods (B/69).
Includes correspondence with A.O. Rankine re echo sounding.