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 force required to open shutters on car 23-EX, noting insufficient effort against friction.
| Identifier | ExFiles\Box 39\4\ Scan108 | |
| Date | 3rd April 1930 guessed | |
| -2- 100°C. was 52 lbs. on one instrument, and in the neighbour- hood of 35 lbs. on a second instrument (the one fitted to 23-EX car). There is scarcely sufficient effort available to open the shutters against the mechanical friction only, i.e. with no return spring fitted. Ha/AJL. | ||