Close-up photograph of an engine cylinder head showing the valves.
| Identifier | ExFiles\Box 54\4\ Scan093 | |
| Date | 1st August 1933 guessed | |
| INITIALS ONLY | ||
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).