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 a photographic valve lift indicator.
| Identifier | ExFiles\Box 17\6\ Scan326 | |
| Date | 22th September 1924 | |
| POINTOLITE LAMP TILTING MIRROR FIXED MIRROR DRUM WRAPPED WITH BROMIDE PAPER CLUTCH CAMSHAFT EXTN. PHOTOGRAPHIC VALVE LIFT INDICATOR FIG. 1 HLS / 22.9.24 | ||