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).
Photograph of a carburetor and intake manifold assembly with a ruler placed on top for scale.
| Identifier | ExFiles\Box 121\3\ scan0042 | |
| Date | 28th October 1931 guessed | |
| Text on ruler: 1 2 3 4 5 6 7 8 9 10 11 | ||