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).
Extract discussing the fitting of a meter to car 7-EX, suggesting a voltmeter is a more suitable and desirable alternative.
| Identifier | ExFiles\Box 60\3\ Scan004 | |
| Date | 1st March 1927 | |
| Driver: X.4049 Extract from PN {Mr Northey} 2/EH.1.3.27. X.4008. The meter referred to by R. {Sir Henry Royce} fitted to 7-EX, is probably quite a useful scheme experimentally, but I do not think it would justify its existence as a permanent fitting to the extent that a volt meter and pair of wires would. Probably also a volt meter would be more quickly read. A flexible tube of rubber or otherwise is not a very desirable thing on a car, if it can be avoided. | ||