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).
Confirming the adoption of 3.5% Nickel steel for the rear axle casing.
| Identifier | ExFiles\Box 49\1\ Scan125 | |
| Date | 3rd January 1920 | |
| X.3769 To By. {R.W. Bailey - Chief Engineer} from R. {Sir Henry Royce} Copy to CJ. Bn. {W.O. Bentley / Mr Barrington} COPY. R4/G3.1.20. X.3769 RE MATERIAL FOR REAR AXLE CASING. With reference to material for rear axle casing, on your suggestion and Mr. Hall's recommendation, I agree that we adopt 3½% Nickel steel for the back axle drop forgings of the central case. R. {Sir Henry Royce} | ||