From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
The torsional rigidity of a welded Bentley III frame at different thicknesses.
| Identifier | ExFiles\Box 99\2\ scan0074 | |
| Date | 26th August 1938 guessed | |
| Bentley III frame. all welded ·128" thick 1750 lbs. ft. / degree ·104" thick 1420 lbs. ft. / degree | ||