A folder entitled 'Stress Office Handbook' divided into several sections. The first contains letters of modifications to be included in the stress office handbook, design manual modifications for the DH. 121 design manual, graphs showing stress data from a 1957 test, specifications and data sheets, De Havilland Company Stress Office Data information on presenting data, prefixes to use etc and various memoranda dated 1947, 1954 and 1955. The second section is made up of a variety of data sheets dated between 1947 and 1955 from the De Havilland Aircraft Co Ltd stress office, and the third section contains similar sheets dated 1952 and 1955. The fourth section contains a drawing office standards section memo relating to spot welding dated 1959, a De Havilland Aircraft stress office data sheet relating to the analysis of flat L.A. shear panels dated March 1956, copies of graphs entitled Shear Strength of flat panels, titanium sheet showing different permissible shear stress levels for military and civilian, parts DHA 67 and DHA 69 dated November 1955, notes relating stressing of flat panel, design procedure dated February 1955 and Shear strength of curved panels, graphs and documents dated December 1953, and a report entitled 'Shear Strength of mainplane and tailplane leading edges' dated September 1954. The final section is entitled 'Drawing Office Handbook Section III' and includes an index, tables, graphs and documents relating to stress data for different metals in different formats.