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).
Blueprint showing the design for grooveless centre main bearings.
| Identifier | ExFiles\Box 173\1\ img191 | |
| Date | 3rd February 1934 guessed | |
| GROOVE LESS CENTRE MAIN BEARINGS LEFT SOLID HERE for LOCATING DOWEL | ||