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).
Letter from A.T. Speedometer Co. Ltd. discussing puzzling variations in instrument test results.
| Identifier | ExFiles\Box 50\4\ Scan190 | |
| Date | 4th April 1928 | |
| CONTRACTORS TO THE WAR OFFICE THE ROYAL AIR FORCE AND LEADING MANUFACTURERS. X4308 A.T. SPEEDOMETER Co. LTD. Trade Mark. DIRECTORS: F. {Mr Friese} T. FISHER, H. {Arthur M. Hanbury - Head Complaints} O. {Mr Oldham} BOOTH, S. D. {John DeLooze - Company Secretary} McKELLEN. Telephone : Fulham 1422. Telegrams : Aytespeedo-Hammer, London. 20, Avonmore Road, West Kensington, London, W.14. Your Ref. EPC5/P. Our Ref. GOB/M. 4th April, 1928 Messrs. Rolls-Royce Limited, Nightingale Road, Derby. PATENTEES & MAKERS OF MAGNETIC SPEEDOMETERS FOR MOTOR CARS AND MOTOR CYCLES. A.T. ELECTRIC SCREEN WIPERS AND PETROL LEVEL GAUGES. MOTOR CLOCKS, TACHOMETERS, MILEAGE RECORDERS. REVOLUTION COUNTERS AND INDICATORS FOR MOTOR CARS, MOTOR BOATS, ENGINES, ETC. ALL CLASSES OF SCIENTIFIC INSTRUMENTS. REPAIRS A SPECIALITY. Dear Sirs, We are in receipt of your favour of the 3rd instant and note your remarks. It certainly appears to us to be very puzzling as to why the instruments should vary under the same tests. We have been carrying out tests on several instruments and we must say that when they are first tested they appear more irregular than when they are tested for the second or third time, when they appear to us to become consistent and never exceed an error of 1½ miles between 18 and 30º centigrade. We trust you will have an opportunity of carrying out further tests and will communicate with us and we will in our turn write you further on the matter. Yours faithfully, for A.T. SPEEDOMETER CO. LTD. C. O. {Mr Oldham} Booth. | ||