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 an indicator diagram apparatus.
| Identifier | ExFiles\Box 79\3\ scan0004 | |
| Date | 13th October 1929 | |
| INDICATOR DIAGRAM APPARATUS LEC-743 PRESSURE GAUGE AIR VESSEL OIL PUMP RELIEF VALVE COCK ROTARY INDICATOR VALVE OIL TANK ELECTRIC MOTOR 1/2 Crank shaft speed FOR READING PRESSURES BELOW ATMOSPHERE PRESSURE GAUGE COULD BE ABSOLUTE & OIL TANK MADE A VACUUM. IT WOULD PROBABLY BE NECESSARY TO HAVE A BATTERY OF 3 OR 4 GAUGES TO COVER THE WHOLE RANGE OF PRESSURES WITH SUITABLE COCKS TO SWITCH THEM IN OR OUT. | ||