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).
Sketch of a mechanical recording device with labeled components.
| Identifier | ExFiles\Box 101\2\ scan0133 | |
| Date | 27th October 1936 guessed | |
| L.O.H.K./Rm.{William Robotham - Chief Engineer} WORM + WHEEL. PULLEY TO SPOOL. SPRING LOADED PENCIL ROLL OF PAPER. H.H. | ||