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).
Comparative performance data for a tyre pump and the lowest speeds of various motor cars.
| Identifier | ExFiles\Box 21\5\ Scan012 | |
| Date | 17th March 1921 | |
| X.4213 17.3.21. X.1692 x 4213 x 1525 x 923. Mr. Hives, ✓ Marmon tyre pump 500 r.p.m. pumps 60 lbs. in 10 mins. lowest slow speed 3.25 M.P.H. 40 M.P.H. speedometer 38.3 M.P.H. (time) Dodge - slowest speed 6.3 M.P.H. 40 M.P.H. speedometer 40.9 M.P.H. (time) Humber - slowest speed 4.5 40 M.P.H. speedometer 38.3 M.P.H. time. 6.EX slowest speed 3.75 M.P.H. 40 M.P.H. speedometer 38.3 M.P.H. (time) GWH.{George W. Hancock - Head Chateauroux} R.R. 385A 100 (T.S.H. 198. 10-12-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 1047 | ||