Recently, Dellinger's phenomena which make the transmission of short waves impossible, attract the attentions of those who are engaged in the wireless-communication or in the observation of the earth's magnetic field and many studies have been made in the ionospheric conditions and magnetic and electric fields. The author investigated the magnetic field of the phenomena occurred during 1935-36, and found that the disturbance in the ionosphere not far from Japan causes the magnetic changes (De) so as to increase the amplitude of the diurnal variation. On comparatively quiet days, we obtained 0.2-0.9 for the ratio De/Ω0, where Ω0 is the departure from the preceding and following midnight. The author calc_??_lated the magnetic potential of the disturbing field by the increase of electrons in the ionosphere. When the increase is constant in the area Se, where σ0+σs and σ0 are the total conductivities when the ionosphere is disturbed and when it is not disturbed respectively, where [φ0]m is the mean normal current function in Se, α the ratio of current in the external and internal portions (Si) induced in the earth-core, and ωe or ωi are the solid angles subtended by Se and Si respectively. From these studies we see that the dynamo-theory is appropriate for interpreting De and the drift current and diamagnetic theories are not, since De is always produced in the sense to decrease the permanent field in the latter theories
The equations showing the relations between the air temperature and the sowing-time (S) and harvest-time (H) of crops (rice plant, winter wheat and barley) at any locality are as follows; where T is the sum of the monthly mean air temperature from May to September and TA is the annual mean of the air temperature and TL is the monthly mean of the minimum air temperature. The theoretical sowing-and harvest-times in Japan Proper and Manchoukuo, which are calculated from the equations given above, are shown in fig. 1-7, which may be useful to find the propertime of sowing and harvest at a newly cultivated locality.
In the present paper the author intends to study the effect of surface-friction on the wind flowing over a circular island. In order to discuss only the effect of surface-friction, it is assumed that the island is flat. The distribution of surface-friction is expressed by F(r), which is a function of r (radial distance from the center of the island) only. The author solved the equation of motion for the following two special cases, and illustrated the distribution of the vertical air current and transversal component of the horizontal air current in four diagrams for the case 1.
In observing the temperature in the upper atmosphere using radiometeorographs emitting waves of frequency varying from 14000 kc/s to 16000 kc/s, we experienced comparatively lower and limited regions in which the signals fluctuated suddenly or entirely disappeared. When the barometer becomes to rise, such regions seem gradually to fall in lower heights. Such lower regions seem to coincide with the c1 layer which was proposed by A. W. Friend in the Proceeding of the Institute of Radio Engineers, Vol. 25, No.12, 1937.
For a vast dimension as that of the actual earth's crust, the effect of the gravity is very great as compared with the effect of strength of the material. Hence, the earth's crust may be represented by powder mass as a model in laboratory. In the present paper, the cohesion of powder mass was measured and it was found that they are about 0.4-0.02gr./cm2. Next the following similitude law of cracks was deduced where λ is the linear dimension of the fractured pieces, d the thickness of powder layer, ρ the apparent density of powder, g the acceleration due to gravity, Fs the cohesion of powder. This law was applied for geophysical problem, and it was concluded that the earth's crust has block structure. and its linear dimension was calculated as about 13km which is in good accordance with the observed value 10km.