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).
Arrangement drawing of a No. 4 Tachometer with dimensions.
| Identifier | ExFiles\Box 165\3\ img144 | |
| Date | 7th February 1935 guessed | |
| LARGE END DIA = 19"/32 TAPER = 1 IN 10 ON RADIUS 1/2" 19"/32 4 1/16" 9 3/4" 3" 7" 7/16 SLOT ARRANGEMENT OF N°4 TACHOMETER WATE... | ||