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).
Requesting a test on two Phantom III oil filters to check back pressure.
| Identifier | ExFiles\Box 136\3\ scan0072 | |
| Date | 18th March 1940 | |
| 1139 File HPS{Horace Percy Smith - Experimental Factory Mgr}/W.Bell. Rm.{William Robotham - Chief Engineer}13/ML.18.3.40. oil filters. We hand you herewith 2 Phantom 111. Will you please carry out a test passing 7 gall ns{Norman Scott} a minute of mobilarctic oil through these filters to ascertain whether the back pressure occasioned by the gauge in each case, is the same. Rm.{William Robotham - Chief Engineer} | ||