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).
Note referencing further instructions for a green lamp switch on a distribution board.
| Identifier | ExFiles\Box 60\3\ Scan084 | |
| Date | 1st February 1928 guessed | |
| X4040 D.O. For detailed instructions re green lamp switch - see X.7740 . EAC.10. Distribution Board. EFC. | ||