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).
Temperature test report for an A.T. speedometer on a 20 HP chassis.
| Identifier | ExFiles\Box 50\4\ Scan306 | |
| Date | 9th July 1929 | |
| X4308. By. {R.W. Bailey - Chief Engineer} from EFC. {E. Fowler Clarke - Electrical Engineer} c. Hs. {Lord Ernest Hives - Chair} EFC {E. Fowler Clarke - Electrical Engineer} 5/AD9.7.29. X.4308. A.T. SPEEDOMETER. We recently made a temperature test of a 20 HP. chassis A.T. speedometer No. C.727-740 11/50. Corresponding to the number of revolutions per indicated mile, for instance 740, for which this instrument is geared, we find the miles per hour readings to be correct at a temperature of 35°C, and to increase progressively by just over 2% at a temperature of 22°C, so that all speed readings at normal temperatures were slightly highered even when the instrument was correctly driven at 740 revs. per mile. EFC. {E. Fowler Clarke - Electrical Engineer} | ||