Photograph of a rectangular metal component with an arrow pointing to an oval indentation.
| Identifier | ExFiles\Box 150\2\ scan0376 | |
| Date | 13th September 1941 guessed | |
| ", | ||
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).