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 memo regarding the high silicon content found in stretched Phantom valves.
| Identifier | ExFiles\Box 66a\2\ scan0077 | |
| Date | 5th May 1928 | |
| Rx c to Hs.{Lord Ernest Hives - Chair} c to By.{R.W. Bailey - Chief Engineer} +6060 H11/EA5.5.28. Laboratory. Phantom - Valves Stretching. With respect to (1) of your memo. R3/M25.4.28. we have now estimated the silicon contents on a valve that actually stretched and one from the same batch. These were found to contain 4.1% silicon, which is on the top limit of our specification and would consequently be more liable to stretch than a steel containing about 3.3% silicon. H1.lR{Mr Ellor} | ||