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).
The standardization of the bye-pass hole on the thermostat valve.
| Identifier | ExFiles\Box 78\1\ scan0109 | |
| Date | 26th January 1921 | |
| X.3563 To EFC. from RHC.{R. H. Coverley - Production Engineer} RHC{R. H. Coverley - Production Engineer}4/LG26.1.21. X.3563 - THERMOSTATS. The bye-pass hole on Thermostat Valve has been put in all Experimental Cars and is now standard. RHC.{R. H. Coverley - Production Engineer} [Signature RHC{R. H. Coverley - Production Engineer}] | ||