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).
Characteristic curve graph showing a cooler's performance.
| Identifier | ExFiles\Box 179b\3\ img264 | |
| Date | 17th February 1933 guessed | |
| CHARACTERISTIC CURVE OF COOLER. BTU'S EXTRACTED/MIN/DEGREE DIFFERENCE BETWEEN MEAN OIL TEMP. AND WATER TEMP COOLER FLOW | ||