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).
Cover page for a document concerning ballast resistance.
| Identifier | ExFiles\Box 46\3\ Scan168 | |
| Date | 9th December 1920 guessed | |
| BALLAST RESISTANCE | ||