Point Discharge in the Atmospheric Electricity, (Part I)
Yokouti, Y.
Abstract
 Point discharge in the electric field of the earth is an important factor for the maintenance of the earth's negative charge, and its observations will have contributions to research on the thunderstorm phenomena. The observation of point discharge at the Kakioka Magnetic Observatory has been begun from June, 1937 and the results of these observations are reported in this paper for one year, from June, 1937 to May, 1938. Point discharge currents have been continuously recorded with a galvanometer and photographical recording apparatus, and the schema of the method of these observations is roughly stated here. For a year, the quantity of discharge q1 that positive electricity flows in the earth through the point from the atmosphere is 53.09 millicoulombs and the quantity of discharge q2 that positive electricity flows out earth through the point to the atmosphere is 108.89 millicoulombs. Thus the difference (q1-q2) and the ratio q2/q1 is 55.80 millicoulombs and 2.1 respectively, for a year. The number of discharge in the case of q1
the period 16h-18h in the diurnal variation. As there is a tendency that the greater amounts of point discharge are observed in thundery weather, the above facts will be understood reasonably from the view-point of the annual and diurnal variations of thunderstorms. Several records are illustrated in this paper. The relations between the atmospheric potential gradient and point discharge, and researches of thunderstorms by point discharge will be studied in future.