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).
Calibration diagram for a Hobson K.S. Telegage, single line type.
| Identifier | ExFiles\Box 61\3\ scan0155 | |
| Date | 7th March 1931 | |
| Y.4.O.I.B. 7-3-31 HOBSON K.S. TELEGAGE CALIBRATION SINGLE LINE TYPE. GALLONS. 0 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 HIGHER ORIGINAL WHITE LINE. GAUGE ZERO LEVEL AT 9°C. GAUGE SET TO LOWER ORIGINAL WHITE LINE. AIR TEMP 2°C. | ||