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).
Laboratory report showing two micrographs of a material, one unetched and the other etched with nitric acid in alcohol.
| Identifier | ExFiles\Box 10\3\ 03-page191 | |
| Date | 7th October 1939 guessed | |
| ROYCE LABORATORY REPORT: X 100 UNETCHED. X 200 ETCHED NITRIC ACID IN ALCOHOL. | ||