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 to Negretti & Zambra detailing the specifications for a 5-inch dial thermometer instead of an 8-inch one.
| Identifier | ExFiles\Box 40\1\ Scan048 | |
| Date | 23th July 1923 | |
| X 3695 Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/LG. Messrs. Negretti & Zambra, 38 Holborn Viaduct, London. E.C. 1 23rd. July 1923. Dear Sirs, We thank you for your letter of the 6th.inst. containing details of the Distance Thermometer. We have decided, on looking at the blue-print, that your 8" Thermometer will be too cumbersome for us to be able to use it conveniently. We therefore intend to order a 5" dia. dial Thermometer, graduated from -10 to 110°C, the degrees to be divided into 1/4 degrees, and a very fine pointer fitted, the connection to be 1/4" gas - 10' of tube - i.e. with the bulb 4 1/4" long. We consider, that if you would give us a certificate showing variations at various points on the scale of this Thermometer when compared with your standard instruments, it would be a sufficient guarantee of its accuracy. It would be of interest if you could give us the weights of the 8" dial compared with the 5" dial Thermometer. If the 8" dial could have been made 8 1/4" overall diameter and weigh slightly more than the 5" Thermometer, we should have preferred the former. We appreciate your remarks with regard to the fine division of the scale but consider that we could read the 5" dial satisfactorily if it is divided up into 240 divisions. It is the overall dimensions of the 8" dial which is alarming us. Yours faithfully, | ||