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).
Note on the types of clutches fitted to various experimental cars.
| Identifier | ExFiles\Box 74\2\ scan0119 | |
| Date | 15th April 1912 guessed | |
| (2) The 1/4" thick cotton belting is at present fitted to the following experimental cars - 1714, 1926, 1761 and 1200. The remaining three experimental cars are fitted with our three experimental plate clutches. | ||