I. On an anomaly encountered in determinations of the density of nitrogen gas

Abstract

In a former communication I have described how nitrogen, prepared by Lupton’s method, proved to be lighter by about 1/1000 part than that derived from air in the usual manner. In both cases a red hot tube containing copper is employed, but with this difference. In the latter method the atmospheric oxygen is removed by oxidation of the copper itself, while in Lupton’s method it combines with the hydrogen of ammonia, through which the air is caused to pass on its way to the furnace, the copper remaining unaltered.