Modifying the equation of potential temperature, two methods of computing vertical velocities are obtained. One of them is the single-station method using the data of pibal and sonde for a single aerological station only, and the other is the several-station method using the data of sonde for several stations. After making nomograms for simplicity in computations, the former method is applied in the case of cold front.

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On the assumption of adiabatic and geostrophic flow, the method of computing vertical velocities using lapse rate of a single station only is obtained. And as the practical exampl of this method, vertical velocities in the vicinity of the Kitty typho on are computed.
Furthbery, integrating perturbation equations, the perturbation method for computing vertical velocities is proposed.

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The lapse rate method of computing vertical velocities which Was proposed in my previous reports on the assumption of dry adiabatics, is extended to the case of wet adiabatics, However, this method is not essentially different from the previous report and we have only to add a correction term depending onmixing ratio. After computing vertical velocities in the vicinity of the Kitty typhoon by this method a conjectured cross section of the typhoon is drawn.

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We find the mathematically correct solutions of the equations of motion for circular isobaric system in the case without friction and verify that an area into which no wind blows is formed around the center corresponding to the eye of storm. And from this solUtlonS'it is 'shown that under certain conditions the vertical air current may exist within the eye.

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By assuming the law of conservation of absolute angular momentum in the travelling atmospheric vortex with vertical axis, it is shown that the vortex moves with the same speed as that of the general current in which no vertical shear exists. Also in the case of a general 'current in which there exists the vertical shear, a formula of the movement of the vortex is obtained.

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The transformation of the equations of motion of a viscous fluid to orthogonal curvilinear coordinates has been discussed by G. B. JEFFERY, and others, but analogous equations for the motion in dynamical meteorology do not appear to have attracted the same attention. The first section of this paper deals with the transformation of the equations of motion in dynamical meteorology. Then the theory is illustrated by applications to cylindrical and spherical polar coordinates.

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Most series of meteorological observations may be considered as a stationary autoregressive stochastic process of order, say, h. In such a series, it is proved that, for the interpolation of an omitted observation by a linear scheme, the observations more than h terms apart before or after the omitted term need not be taken into consideration. Precision formulae, by which we can indicate the probability that the true value be within any range around the estimated value, are derived for various cases.
The theories and formulae are extended to the case of vector or multivariate time series which may often come out in practice.

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At the end of the Great War II, many valua b le data have been burned up by Japanese Army and Navy. I have a good luck to find some of a restricted data, a part of which I wish to publish in the present paper.
Those atlases of sea surface visibility information have been collected and compiled by Japanese Navy for the period extending over 10 years (from Sept.1923 to Aug 1933, inclusive. ) On Sept.1 st of the year 1923, there was the famous catastrophe named the Great Kwanto Earthquake in Tokyo and its vicinities, so the many informations from ships were destroyed. Hence the present data is believed to be most reliable. Marine data reports from Japanese Navy and civil ships attained, about twenty thouthands in number. EXCELLENT visibility means that it is visible beyond horizon, and POOR visibility means that it is quite obscure and the horizon can not be seen at all. The seasonal average percentage of days on which excellent or poor visibility was observed has been plotted in each 2.5-degree square. The figure in the bracket gives the number of observations.
The lines of equal percentage for every 20 ey; are shown by full lines. From these figures, we can decidedly conclude that, in the low latitudes, the visibility is excellent throughout the year. In the high latitudes poor visibility predominates, especially in the summer season. In Far East, the monsoon in summer is, directed from South to North, so the conditions favorable for advection fogs sucl as (1) large difference between the temperature of the southerly air and that of the sea to E and N of Japan; (2) not too high wind velocity, high relative humidity and stable stratification are fully satisfied in the monsoon air-current. So fog is quite frequent in the summer season in the said areas. In colder half of the year, the obscuring snow in the rear of winter cyclones on the northern sailing routes lessens visibility as a rule.

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In the Ina valley, Nagano Pref. in Japan, we can point out, as a remarkable climatic characteristic, the prevalence of strong southerly wind throughout the year. Almost all houses in this region face toward the east against the general tendency of this country. Such a characteristic may be caused mainly by the prevailing southerly wind. The author investigated the precise geographical distribution of the prevailing winds and facing dire ctions of the houses in this region. Comparing these two values with each other, we can find that their differences of directional angles are very small ( < 20°-68 %, <40°-92 %). Moreover various wind protection equipments are installed on the southern side of houses: windbreak forests. “Shibukiyoke ” (a protection board on gables against wind and rain splash), “ Goya ” (an outdoor lumber room under pent-roof), windbreak fences made of straw etc.. Thereare many houses that have such equipments installed also on their northern and western sides. The reason for it is that the northerly wind is the next most frequent and that sometimes the westerly gales blow. Therefore the calmest direction is the east and the frontage of rural houses is obliged to face toward the east.
A large part of rural houses are very low in their height. This is also caused by the prevalence of strong winds.

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A handy wind-direction and speed robot using carrier wave of 416 M. C. modulated by audio-frequency through ordinay L-C oscillation is designed and tested for the purpose of southern island use. Also the temperature effect upon the transmitter and receiver is investigated for the range of -23°to 20° with the results that the equipment may be used with tolerable accuracy for normal conditons.

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In Part I, mathematical treatment of the problems, is presented to establish the theoretical support and leading principles of the experiments and actua techniques.
In Part II, experimental. results based upon the mathematical principles are described for various actually designed instruments.
In Chapter 1, Part I, rigorous discussions are given for the force and moment experienced by two flat plates with arbitary chord lengths, angle of stagger and decalage in two-dimensinal incompressible ideal fluid, The problem is solved after the method of I. E. Garrick but more general result due to J. Hodgkinson and E. G. C. Poole is analysed and the connection is found between them, Formulae for the cases of two plates in close proximity are given. Numerical calulations are carried out for symmetrical biplane wind vanes and fundamental principles are found for design use.
In Chapter 2, Part I, exact formulae are induced for the calculation of the flux through the ventilator tubes with straight, circular, elliptic or hyperbolic sides in two-dimension. Numerical evaluations are done for the cases of straight and hyperbolic sides.
In Chapter 3, Part I, basic considerations of cup anemometers are effected, and numerical calculation of the static moment of cylindrical windmill with two rotors is made for an example,
In Chapter 1, Part If, three types of combined wind vane and anemometer with twin-rudder, conical tail ring, or hollow single rudder each of which may be regarded as posessing biplane characteristics, are tested in the wind tunnel. After systematic investigation based upon the theoretical oint of view one type of them is decided to be favourable for directional stability. Also anemometer windmill blades are discussed, which are indifferent to the effect of wind turbulence,
In Chapter 2, Part II, systematic studies on the basic forms of straight ventilator tubes are done. Two effective. groups are found. The test was also carried out for tubes with free-running windmill. The trends of the experiments agree with theory. Numerous actual designs with, bent air passage are tested for radiosonde use. The theoretical leadership still holds in such complicated examples.
Cowled windmill models are tested of their torqud and power and compared with those of windmill alan. e. The effect of the cowling is not highly promissing but several important fundamental characteristics of windmill are revealed. Free-running windmill or windmill anemometer is also treated. A full-scale windmill is experimented in natural wind.
Two types of cowled hot-wire anemometer are investigated of their directional insensitiveness to the wind.
In Chapter 3, Part II, cylindrical windmill' model with two rotors is tested of its troque and power, and also discussed as an anemometer.

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A circular dish is set in a wind tunnel, and the amount of evaporation is measured by weighing, And experimental formulae are made. These formlae are a variation of Trabert's type, Comparison with Yamamoto's results is performed. The effect of the edge diminishes the amount of evaporation, The amount of evaporation due to diffusion decreases with the time duration of evaporation.

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The writer analysed the s easonal disease, beriberi, by using the means of auto-correlation method and applying the cyclic distribution. The purpose of this study is to find out the type of the seasonal periodicity and the distribution curve of beriberi in the main cities of Japan.
1) Analysis by means of auto-correlation method:
I calculated the auto-correlation coefficient of the d eath rate of beriberi in 5 years from 1926 to 1930. Then I draw correlogramm by using auto-correlation coefficient.
There is the clear period of 12 months which has wide amplitude in four cities in the Kansai district and two cities in the Kanto district. While in the cities in the south Kyushu district and in the Hokkaido district, there exist two periods, one is the period of 12 months which has wide amplitude and the other is the small period of 6 months even though they are not so clear.
2) Means of applying the cyclic distribution: I tried to express the death curve of beriberi b y composition of two periods which have one year normal cyclic distribution. But the phase of the second period slips down by half a year. The first period was supposed to have the cause of outbreak in summer while the second period in winter.
The temporal distribution curve is expressed by
In the case of Osaka City and F ukuoka City, I calculated the value of constants. Next if I calculate, by using the constants, the monthly death rate of beriberi in these two cities as the actual value, I can get the distribution curve shown in the graph, and find out that the actual measurement and calculation coincide well.
Judging from the above-mentioned fact, I can imagine that there will be some reason easy to cause beriberi death even in. winter in some district.
The writer tried the time series analysis of the seasonal disease, beriberi to find out the type, of the seasonal periodicity and the distribution curve of, beriberi by using the means of auto-correlation method and applying the cyclic distribution.

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Taking into consideration of the atomospheric extinction, refraction, and scattering, the formulae for the received intensities of the night-sky light into a solid angle was introduced geometrically, where the luminescent layer assumes a geoconcentrics pherical surface of the uniform radiant intensity, An attempt was made to evaluate the height of the layer from the observed data with the aid of these formulae. Finally, discussing the general assumptions, the authors propose possible geographic distributions of the radiant intensities and the simultaneous observation to which the for mulae are applicable.

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