Cross-section blueprint of a mechanical component with a handwritten production modification.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan149 | |
| Date | 8th November 1929 | |
| 4 HOLES LIKE THIS NOW ON PRODUCTION Ten. 8/11/29 | ||
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).