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).
Results of testing Duckham's lubricating oils.
| Identifier | ExFiles\Box 145\3\ scan0109 | |
| Date | 15th July 1937 | |
| 1235 Sg.{Arthur F. Sidgreaves - MD} from Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}7/R.15.7.37. DUCKHAM'S OILS. We have examined Mr. Duckham's Bentley which has run on his lubricating oil, the results are very satisfactory. We have completed some bench tests on consumption. This oil does not appear to be inferior in this respect to our standard brands. We are running 26.G.VI, the first 15,000 miles! Wraith on Duckham's oil. The only concern we have at present is whether there will be any sludge formation under high duty Continental conditions. When the car has been out there 3 or 4 weeks we can get the testers to examine the crankshaft; if satisfactory, we propose to circulate a standardisation sheet. Rm.{William Robotham - Chief Engineer} | ||