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).
Graph comparing backlash in Fellows 17 Tooth, Fellows 16 Tooth, and Adamant hourglass worms.
| Identifier | ExFiles\Box 95\1\ scan0460 | |
| Date | 2nd December 1937 guessed | |
| SHOWING COMPARATIVE BACKLASH IN FELLOWS & ADAMANT HOURGLASS WORMS. Legend: FELLOWS 17 TOOTH GENERATING CUTTER. FELLOWS 16 TOOTH GENERATING CUTTER. ADAMANT WORM. Y-Axis Label: RADIAL MOVEMENT OF FOLLOWER TO MAINTAIN CLOSE CONTACT. Y-Axis Values: .020, .016, .012, .008, .004, 0. X-Axis Label: ANGULAR ROTATION OF HOURGLASS WORM. X-Axis Values: 360°, 270°, 180°, 90°, 0°, 90°, 180°, 270°, 360°. | ||