On the Daily Distribution of the Pulsation(pt) in Electromagnetic Field
Two different types exist in pulsation of terrestrial electromagnetic field. For the one type, separate bursts of oscillations are characteristic, on a quiet trace background, while for the other type series of pulsations last for some hours. We call the former pt and the latter pc, in accordance with the proposal by Dr. A. Romana, Chairman of the Committee of Rapid Magnetic Variation and Earth-Current.
K. Yanagihara investigated the frequency distribution of earth-currents pt at Kakioka for 1934-1953, and he concluded that the most frequent occurrences are found at about 23 hour in local time. While V. A. Troyickaya investigated the daily distribution of earth-currents Pt in Central Asia for 1951-1952, and she concluded that these pulses occurred simultaneously over the whole earth, and they showed a diurnal variation in G. M. T. In order to confirm whether the diurnal variation depends on G. M. T. or not, the author investigated the frequency distribution of pt at Kakioka, Sitka, Cheltenham and Toledo in the same period 1951-1952 as in V. A. Troyickaya's work. The results show that the time distribution of pt depend on the local time.
Corrigenda is attached to this text.