Correspondence between Barnes Wallis, Hartley Pratt and Charlies Marlin, a Director at Vickers, amongst others. Includes:

- Letters to Wallis from Marlin and Pratt during a medical leave of absence taken by Wallis in December 1919

- Correspondence between Wallis and Pratt in February/March 1920 regarding the ongoing structure of the Drawing Office at Barrow

- Letter from Wallis to Commander Hunsaker of the US Navy, dated 22 January 1921, asking for advice following the stagnation of rigid airship construction in the UK