Resistance Vacuum Gauge

Abstract

Pirani has suggested a resistance vacuum gauge, under the principle that at low pressures the thermal conductivity of the gas is a function of the pressure it gives. In consequence of this change in the thermal conductivity, the electric resistance of the wire changes with pressures of the gas surrounding it. This suggestion has been embodied and improved by C. F. Hale whose manometer has been found to give certain results down to 0.00001 mm. of mercury or to 0.01 bar. For its handiness to be used in the laboratory or the factory the present writer has made an experiment upon. the manometer with a fairly good result described below.