Atmospheric Electricity

Abstract

DR. CUREE, in his review on the above subject (NATURE, Dec. 18, 1926, p. 894), has inadvertently drawn an erroneous inference with regard to the reduction factors used by Dr. Mauchly for the Carnegie potential-gradient observations. The manner of obtaining these factors is described by Messrs. Ault and Mauchly on pp. 207–209 of the volume (Researches, Department of Terrestrial Magnetism, vol. 5) reviewed, and it is stated by them that the values finally adopted depend on the reduction-factor determinations made during the years 1915 to 1921, namely, during cruises IV., V., and VI. (not VI. alone, as Dr. Chree infers).