Check of revolutions per mile for a speedometer.
| Identifier | ExFiles\Box 59\2\ Scan027 | |
| Date | 16th May 1930 | |
| X4308. CHECK OF REVOLUTIONS PER MILE OF SPEEDOMETER. Speedometer :- No D999. 720. 1/50 20 HP Taken from stock Date :- 16-5-30 Mile reading | Counter reading. Observed at finish. | 00461 | 29066 Observed at start. | 00374 | 13409 Difference | 87 | 15657 Counter revs. per mile | 180 Instrument revs. per mile. | 720 28.10.29. | ||
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).