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).
Micro-examination report on Phantom lll valve springs made from Brunton's high carbon steel wire.
| Identifier | ExFiles\Box 96\2\ scan0156 | |
| Date | 20th October 1936 | |
| X 354 Micro-Examination Report. M.1207. To Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} HL3/AG.20.10.36. Laboratory. Re: Phantom lll Valve Springs in Brunton's High Carbon Steel Wire. In addition to the fissured condition of the surface of the wire as demonstrated to you under the microscope, these springs contained the weakening ferritic streamers similar to those of which you already have photographs. H1. HE | ||