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 wire spool and mechanical apparatus.
| Identifier | ExFiles\Box 175\2\ img025 | |
| Date | 30th October 1940 guessed | |
| 2006( | ||