Abstract
This paper was published in additional pages of “Annual Report of the Central Meteorological Observatory of Japan-Magnetic Observations for Years 1917 and 1920, ” and will reappear in “Japanese Journal of Astronomy and Geophysics, Vol. III.” An abstract in Japanese is written in this journal (this Vol. p. 173). Chief conclusion in this paper is proof of proportionality of the square of mean range and the mean variability. Some discussions about the mean of the squares of range and about natures of hourly range are added. Theories proved in this paper may also be used to discuss variations of any natural phenomena.
