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).
Request to the Experimental Department to calibrate two temperature warning devices.
| Identifier | ExFiles\Box 165\4\ img182 | |
| Date | 29th May 1933 | |
| 00 53678/29-5-33. Experimental Dept. Mr. West, Temperature Warning Devices to L.O.P. D52984, 53536, 53304. Will you please calibrate the two devices as above, such that the green & red lamps light at 70°C. (atmospheric pressure) S. Mansell A.I.D. | ||