Northward and southward shifting of ionic clouds of the sporadic-E region is discussed from a statistical research for the sporadic-E region ionization at five observatories in Japan, and relations between the direction of the shifting and the type of the daily variation of the terrestrial magnetism are obtained.
All these results are suggestive to an assumption of circulatory motions in the ionospheric atmosphere as a cause of S_q and S_D.

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From a statistical research on virtual heights of the ionosphere for various locations, circulatory motions in the ionospheric atmosphere are assumed.
It is suggested by the dynamo theory from the assumption that the lower layer of the circulatory motions may produce S_q and the upper layer may produce S_D.

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The disturbance of the atmospheric potential gradient caused by the cloud of the eruption smoke of the Volcano Yake-yama, Niigata-prefecture, was recorded at the Kakioka Magnetic Observatory on Feb. 5th, 1949.
The disturbance is negative and its extreme value is less than -1200 volts per meter. The distribution of the negative charge in the smoke-cloud is discussed.

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The intensity and direction of magnetic polarization of a horizontal stratum of Pleistocene deposits are measured by means of an induction-type magnetometer. The thickness of the examined part of the sedimentary layer, Narita-bed, is about 7 meters, and its age is ranged from -4.2×10⁴ to -7.6×10⁴ years corresponding to the uppermost and deepest parts.
Roughly speaking, the direction of the magnetic polarization of each part of the layer is not much different from that of the present geomagnetic force, though there are fairly systematic deviations within a few tens degrees.
From the results of examination of statistical reliability of the apparent direction of polarizationi and of the constitution of remanent magnetism, it was proved that the direction of polarization ought to agree, within the error of a few degrees, with the geomagnetic force at the time of deposition of those materials.

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The author observed the micropulsation of the terrestrial magnetism by the specially designed induction magnetometer at Onagawa, near Sendai, and studied the statistical investigation of the micropulsation which occured at the time of the magnetic disturbance.
Main results are as follows:
1) Micropulsations are accompanied by the magnetic disturbance, specially, the large amplitude of micropulsations occure at the time of the magnetic storm.
2) The sinusoidal regular micropulsations occur much more frequently in the daytime. The author considered that it occurred when the corpuscles coming from the sun penetrated into the ionosphere.
3) Though the sudden commencement occurs simultaneously over the whole area of the earth, the amplitude of the oscillation of dH/dt in the hemisphere at daytime is greater than that in the hemisphere at night. This character is very remarkable and occurs almost without exception. Also a remarkable micropulsation of dH/dt at the sudden commencement; frequently took places during the summer and equinox.
4) The author observed the variation of the magnetic micropulsation during the solar eclipse on May 9th, 1943, at wakkanai, Hokkaido and Onagawa, near Sendai, and found that the time variation on the terrestrial magnetic field at the time of solar eclipse is the effect of the neutral corpuscular eclipse, and the velocity of the corpuscle is supposed to be 34, 000Km/sec.
5) The current system of the magnetic disturbance accompnied by the irregular micropulsation at the time of the magnetic storm is the same as that of the “Positive Bay Disturbance”. The irregular micropulsation is very remarkable at the perid of the mainpllase of the magnetic storm, and its current system is situated in the auroral zone.

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