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 oil samples from experimental cars to test filter change intervals.
| Identifier | ExFiles\Box 136\3\ scan0065 | |
| Date | 9th February 1940 | |
| 1139 To Rm{William Robotham - Chief Engineer}/FD.{Frank Dodd - Bodies} from Rm.{William Robotham - Chief Engineer} We should like samples of the oil taken from the crankcase of all our experimental cars every month, and recorded on blotting paper charts so that we can ascertain whether the recommendation in France that the filter should be changed every 5,000 miles applies to England, or whether this is an unnecessary extravagance for English conditions. Rm.{William Robotham - Chief Engineer} | ||