The Measurement and the Calculation of the Liquid Helium Vapor Pressure-Temperature Scale from 1° to 4.2°K

Abstract
Measurements between 1.2 and 4.2°K on a paramagnetic salt using a mutual inductance bridge apparatus indicate errors in the presently accepted liquid helium temperature scale amounting to 12 millidegrees at the λ point. These data, together with those of Kistemaker, are found to be in good agreement with a temperature scale calculated from the other thermodynamic properties of helium. The calculated scale is further confirmed by a comparison between the calculated and observed latent heat of vaporization. Accepting as correct the boiling point determination of Keesom and Clusius, the ostimated accuracy of the proposed temperature scale is 1.5 millidegrees below the λ point and 3 millidegrees above the λ point.