Part I. Earth-Current and Earthquake. Eliminating the so-called universal factors of earth-currents with two independent E-W Components, 1.5km. and 0.1km. long respectively, we find the following results. Earthquakes, especially larger scale ones, are frequently occurred near the max. or mim. points of the special variation of the above eliminated curves which have usually no appreciable change except the anomalous electrode change. This variation begins to occur some hours before the earthquake. The earthquakes are classified in three types, I-, D-, and M-type according to the increasing, decreasing and both mixed variation of the eliminated potential difference, in which case potential is taken as positve when west high. The geographical distribution of the three types is shown in Fig. 1, showing some intimated relation to the topography, or gravitational anomaly near the island. The amplitude AmV/100m and period T in hours of the variation lasted before the earthquake occurrence will be approximately expressed by the following empirical formulae in which Δ_??_1, whereΔis the distance from the observatory to the epicentre and ε and a, etc, are some constants. Some possible considerations regarding to this variation are proposed.
Eliminating the so-called universal variations with two independent base lines, we find that earth-currents va_??_ in some manner with the activity of the earthquakes and their after shocks. The relation between the mode of the variation of earth-currents and mechanism of earthquake is not clear at the present time.
We measured water temperature, hydrogen ion concentration, SiO2, P2O5, and Cl Contents of the water of the rivers Huzigawa and Kanogawa over the period from Sep. 1935 to Sep. 1936. As the water of the Huzigawa was found to be turbid for the most part of the year, Denigeés' method for P2O5, as it is, could not yield but very rough value, whose average came out to be 0.060mg/L. We tried a new method to make the turbid water transparent, adding a drop of 50% H2SO4 and 10mg of alum for 100cc of the test water and filtering after a day or two. Then we applied Denigeés' method and obtained 0.218mg/L as the average value. The discrepancy of the above two values, which is too serious to be attributed to the difficulty in colorimetry for turbid test water, may in all probability be due to the dissolution of P2O5 contained in the suspension during the process of making transparent. We now come by a question as to the meaning of P2O5 content of turbid water whose suspension contains itself P2O5. Apart from this question, it is a matter of interest that Mr. K. Kimura, measuring P2O5, SiO2, etc. on board a ship at several points in north Suruga Bay in 1931, found that P2O5 content of the surface sea-water at the point 1400m SW from the mouth of the river Huzigawa amounts to 0.250mg/L-the value markedly large in comparison with those at other points, while Mr. E. Kurasige in 1933 reported 0.0321mg/L as the average value of P2O5 content of the water of the Huzigawa-the value not reconcilable with the former. In the light of our present investigation, it may be possible that P2O5 contained in the suspension in the river water dissolves under suitable condition in the sea, and if this is the case, the above mentioned relation can be explained at once. It is also a matter of interest that, “Sakura-ebi” (Sergestes prehensilis) which had been found only near the mouth of the Huzigawa was found last year in the offing of Okitu and Miho where P2O5 content is large next to the mouth of the Huzigawa according to Mr. K. Kimura. It seems that abundance in P2O5 has some connection with the yield of Sakura-ebi, but it is not exactly known. Jan. 15, 1937, At Misima.
A vortex of sand is often observed in the shallow sea along beach. By producing waves having various periods in the water tank of the hydraulic laboratory, the authors have taken photographs of the motion of sand particles forced by waves and discussed the mechanism to produce the sand vortex.
During the cold season the directions of clouds of the lowest stratum are often opposite to that of the surface currents. On such an occasion as the direction of the surface wind is NW and that of cloud SE, an unexpected weather appears. This occurs when Kwanto districts just entered into the region of high pressure, and then warm air on the ocean and the cold on the land are clearly defined. The condition that the upper currents are opposite to the lower depends entirely upon the proximate existence of two air masses stated above. Warm and wet air advances towards the colder land and gradually becomes cool. The stratified cloud accompanied by drizzle thus arises.
If we assume that the mixing lengths of x, y-components (x-axis coincides with the direction of gradient wind) are not equal, and write the components of eddy velocity in the form following Prandtl's treatment, we can readily derive the coefficient of eddy viscosity along x-and y-direction in the form: As the value of U and V, we adopted Ekman's spiral which has been observed by Mr. Fedor Schwandke at Hall/Leipzig and Hannover during the year from 1930 to 1933, and determined the value of ∂U/∂z, ∂V/∂z at each height by graphical method. First we adopted Taylor's equipartition theory of edding energy, and discussed the value l1, l2 at each height. Thus we found that in the lower atmosphere the relation l2>l1 holds, which, with the approach to the height of gradient wind, tends to the relation l2=l1. Next we rely on F. J. Scrase's observation. Assuming the relation l1=l2, we discussed the distribution of eddy velocity at each height. The value u'/v' thus obtaind gives a maximum value at a height of 100m and decreases with height. Assuming rather a general case in which neither the condition v'2=u'2 nor l1=l2 exists, wealso obtaind approximately the relation l2_??_l1, in the lower atmosphere. On account of the above discussion, we may conclude that the coefficient of eddy viscosity has a large value in the perpendicular direction to the general flow. Adopting the coefficient of eddy viscosity k1, k2 we solved the equation of eddy motion. As the relation between surface wind and gradient wind, we have the following form. which, of course, in case of k1=k2 reduces to Taylor's relation.
§1. Einleitung. §2. die Fortpflanzungsgeschwindigkeit des barometrischen minimums und die Bewegungsgeschwindigkeit der Luft im. Cirrusniveau. §3. die Bewegungsrichtung der Zyklone und die Richtung des Cirruszug. §4. die Stromlinienkarte im Cirrusniveau. §5. Zusammenfassung. (1) Im allgemeinen, Bewegungsrichtung des barometrischen minimums fadlt mit der Richtung des Cirruszuges zusammen. (2) Die Fortpflanzungsgesehwindigkeit des baro. minimums “v” sint folgende Formel gegeben v=0.94c-18 (m. p. s) hier, c: die Bewegungsgeschwindigkeit der Luft im Cirrusniveau. (c>23).
In his previous paper (This Jounal II 14 (1936) 447), the author reported the marked influence of silicate on Denigès-Atkins' method of phosphate determination. He has recently found that this influence is not due to silicate, but due to fluoride or silicofluoride. There is almost no effect on the phosphate determination, if sodium silicate is used instead of sodium silicofluoride.