Hand-drawn electrical wiring diagram showing multiple switches and coils.
| Identifier | ExFiles\Box 167\1\ img095 | |
| Date | 18th February 1937 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).