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).
Schematic diagram of an engine cooling system featuring a thermostat and butterfly valves.
| Identifier | ExFiles\Box 180\M3\M3.6\ img010 | |
| Date | 1st May 1919 guessed | |
| Sketch No 2 Cylinders water pump thermostat The thermostat as shewn in its hot or expanded position Butterfly valves Radiator | ||