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).
Oil consumption figures for specific trials cars over a three-month period.
| Identifier | ExFiles\Box 144\3\ scan0301 | |
| Date | 4th May 1938 | |
| 1220. S/W. Rm.{William Robotham - Chief Engineer} Oil Consumption. Cx{Major Len W. Cox - Advertising Manager}17/KW4.5.38. I attach hereto figures taken over a period of three months in respect of the undermentioned Trials Cars :- 3-CP-10 3-CP-30 3-CM-87 GHO-50 Att: RC{R. Childs}3/L3.5.38 RC{R. Childs}4/L3.5.38 RC{R. Childs}5/L3.5.38 RC{R. Childs}6/L3.5.38 Cx.{Major Len W. Cox - Advertising Manager} Hul | ||