A multiple manometer and piston gages for precision measurements

g have been repeatedly intercompared and the tech- nique <,f their operation developed, the purpose being twofold:(1) To increase the accuracy of the measurement of pressure as one of the thennodynamic variables, (2) to investigate the reliability of the pi-ton gage as a primary standard instrument. II. DESCRIPTION OF MANOMETERThe 15-bar manometer in its present form, as shown in Figure 1, i~the result of a gradual development extending over a period of The original design, as developed by Dr. Edgar Buckingham, provided foe an instrument for routine laboratory use, made so that MANOMETER