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 The Cambridge and Paul Instrument Company responding to queries about a Chronograph's performance.
| Identifier | ExFiles\Box 138\2\ scan0028 | |
| Date | 23th May 1924 | |
| +4630 TELEGRAMS: INSTRUMENT, CAMBRIDGE. CODES: A.{Mr Adams} B. C. (5TH AND 6TH EDITIONS); WESTERN UNION; BENTLEY'S. TELEPHONE: CAMBRIDGE No. 615. THE CAMBRIDGE AND PAUL INSTRUMENT COMPANY, LIMITED, INCORPORATING THE CAMBRIDGE SCIENTIFIC INSTRUMENT CO., LTD., CAMBRIDGE, AND ROBT. W. PAUL, LONDON. HEAD OFFICE AND SHOWROOMS: 45, GROSVENOR PLACE, LONDON. S.W.1. WORKS: LONDON AND CAMBRIDGE. REGD. TRADE MARK. CAMBRIDGE, ENGLAND. YOUR REF...........Hs{Lord Ernest Hives - Chair}/Rml/LG IN REPLY PLEASE QUOTE...WGC/MV.. 23rd May, 1924. Messrs Rolls-Royce, Ltd, Nightingale Road, DERBY. Dear Sirs, We are pleased to note from your letter of the 22nd instant that the Chronograph is working satisfactorily. In reply to your queries: (a) The adjustable resistance was inserted in order that you should be able to adjust the current through the electro magnet coils. You can undoubtedly keep the temperature down by putting in rather more resistance. (b) We would suggest that the gaps of the electro magnets should be so adjusted as to give a movement of the pen on the paper of about 1 to 1 1/2 mms. This gives a perfectly readable deflection and will readily record vibrations up to 100 per second, and at a suitable paper speed, time intervals of 1/500 of a second can readily be measured. (c) We regret to note that one of the electro magnet bobbins has become loose on its core. This is doubtless due to the warming up of the cores, but we think you will not find that this is | ||