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 Negretti & Zambra regarding the price and specification of dial thermometers.
| Identifier | ExFiles\Box 40\1\ Scan047 | |
| Date | 6th July 1923 | |
| X3695 NEGRETTI & ZAMBRA, OPTICIANS and SCIENTIFIC INSTRUMENT MAKERS. HEAD OFFICE: 38, HOLBORN VIADUCT, E.C.1. BRANCHES: 5, LEADENHALL ST.{Capt. P. R. Strong}, E.C.3. 122, REGENT ST.{Capt. P. R. Strong}, W.1. FACTORY: HALF MOON WORKS, BARNSBURY, N.1. FOREIGN BRANCHES: BRUSSELS. OTTAWA. TORONTO. VANCOUVER. FOUNDED 1850. HIGHEST AWARDS AT THE INTERNATIONAL EXHIBITIONS OF LONDON 1851. LONDON 1862. PARIS 1878. PARIS 1900. BRUSSELS 1910. TURIN 1911. GHENT 1913. CABLE: NEGRETTI, LONDON. TELEGRAPHIC ADDRESS: NEGRETTI, CENT, LONDON. TELEPHONE: HOLBORN 583. (BRANCH EXCHANGE) 38, HOLBORN VIADUCT, LONDON, E.C.1 Our Ref:- PEN/GB. The Buyer, Messrs. Rolls-Royce. Ld., DERBY. 6th.July.1923. Dear Sir, Further to Mr. Smith's call upon you the other day regarding Dial Thermometers, we beg to say that the price of an 8" dial thermometer, divided in single degrees, with 10' of compensated capillary tubing, bulb fitting screwed 1/4" gas would be £17.15.0. We enclose a drawing No. 440 showing the dial graduated with 150 divisions and should certainly not advocate dividing a similar dial with more than 200 divisions. If you divided it with 800 divisions which would be quite possible from the dividing point of view, but the divisions would be so blurred that it would be practically impossible to take a reading. On the other hand, with graduations about the same as the enclosed, you can easily sub-divide this by the eye into quarters, especially if we make you a very fine pointer. We notice that you state 1/4" gas fitting; this will necessitate a bulb 15" long, whereas if you could have a 1/2" gas fitting, the bulb would be only 4 1/2" long. We understand that a high degree of accuracy would be required with these thermometers and as suggested by our Representative, they could be sent to the National Physical Laboratory for verification. The charge from the N.P.L., for testing and issuing a certificate would be £5.0.0.. As an alternative we might suggest that when the thermometers were finished, one of your Representatives could call at our Works and see them tested against our standard thermometers. This would enable you to see that the certificate which we would issue would be correct and it would save the cost of the N.P.L. charges. We shall be pleased to give you any further information. Yours faithfully, Negretti & Zambra Enc. | ||