Photograph showing pitting on an engine valve head.
| Identifier | ExFiles\Box 127\5\ scan0057 | |
| Date | 14th January 1943 guessed | |
| ", | ||
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).