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).
Title page for a document concerning a switchbox.
| Identifier | ExFiles\Box 46\3\ Scan226 | |
| Date | 18th April 1921 guessed | |
| SWITCHBOX ________ | ||