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).
Table of viscosity ratios for various gear and engine oils at different temperatures, measured using the Redwood method.
| Identifier | ExFiles\Box 144\1\ scan0032 | |
| Date | 9th September 1912 guessed | |
| RATIOS FOR VISCOSITY REDWOOD | | 60° F | 130° F | 212° F | |---|---|---|---| | Vacuum Gear Oil | --- | 471 | 69 | | Ratio | --- | 100 | 18.9 | | Battersea Gear oil B | --- | 2008 | 212 | | Ratio | --- | 100 | 10.55 | | Vacuum Engine Oil (B) | 4868 | 391 | 80 | | Ratio | 100 | 8.03 | 1.64 | | Vacumm Engine Oil (C) | 4560 | 387 | 80 | | Ratio | 100 | 8.49 | 1.75 | | | | 100 | 21.67 | | ||