Confirmation to fit half Silchrome and half Firth's Crown Steel valves to model 23-EX.
| Identifier | ExFiles\Box 11\3\ 03-page040 | |
| Date | 9th April 1930 | |
| X7940. To RHC. {R. H. Coverley - Production Engineer} From Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} 4/MJ.9.4.30. This is to confirm that you will fit half Silchrome and half Firth's Crown Steel valves to 23-EX. Three complete cylinders of each type. Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} | ||
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).