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 schematic of a mechanical assembly with various design annotations.
| Identifier | ExFiles\Box 56\1\ Scan024 | |
| Date | 20th January 1931 guessed | |
| THIS CENTRE MUST BE CONCENTRIC. CAN BE ROUND OR SQUARE: IF SQUARE MUST BE RIVETED HENCE SCREW FROM BOTTOM ALTERNATIVE SCREWS ACCORDING TO UPPER PIN HAVING SQUARE OR ROUND ENDS 30° | ||