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).
Failures of Cambridge Thermometers and comparing them to a superior Foxboro instrument from the U.S.A.
| Identifier | WestWitteringFiles\F\February1921\ Scan28 | |
| Date | 10th February 1921 | |
| To EY. from Hs.{Lord Ernest Hives - Chair} C. to ER. RR/A 3 X.3565 X.3903 RE. THERMOMETERS. Cambridge & Foxboro' (U.S.A) We have had three or four cases of failures with the Cambridge Thermometers of the soldered joint breaking away. Whilst I was in the U.S.A. they showed to me a number of Cambridge Thermometers which had failed. They are, of course, in a worse position than we are because it is impossible to get them repaired. They showed to me a Thermometer made by the Foxboro' Company which is equivalent to the Cambridge instrument. The joints on the Foxboro' Thermometer were very much better carried out, also at the point where the joints occurred, they had armoured the tubing so that it was impossible to kink it at the joint. They had also got, what I considered, a very good method for fixing the bulb into the water pipe. On the bulb is a coned face similar to a union. The joint was made in exactly similar way to what an ordinary union water joint is made. The advantage of this joint is that as soon as the nut is turned, the bulb is loose and there is no tendency for it to be twisted round. The Foxboro' instrument is also very good for reading dead-beat. We have had several Cambridge instruments in which the needle has vibrated. With reference to the question of fitting Thermometers to our cars again. I took this matter up with R.{Sir Henry Royce} and he thought the best way was to redesign a Thermostat so that it operated the shutters in the front of the radiator. Contd. | ||