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).
Hand-drawn circuit diagram for a DC motor.
| Identifier | WestWitteringFiles\K\June1923\ Scan41 | |
| Date | 11th June 1923 guessed | |
| R + | ||