Numerous studies of rainfall have hitherto been carried out mainly from a synoptic meteorological stand-point, while diverse trials to describe climatic rainfall situations were attempted by E. Fuxin and others in Japan.
In this paper, the various results of statistical and climatolo g ical analysis applied to rainfall data are coordinated by synthesizing and partially correcting the author's separate contributions to statistical study concerning the varieties of precipitation in Japan.
Firstly, a certain unified functional expr e ssion of frequency distributions obtained on the basis of the actual rainfall and rain-duration data was schematically contrived to have fairly rational fitness for the arbitrary time scale of rainfall observation, and moreover the several geographical distributions of estimated parameters contained in such a unified functional distribution were explained rather in detail from a climatological viewpoint.
Secondly, cross and auto-correlation analysis and regression analysis were elaborately performed to investigate the localities and time dependent relations appearing in the short-range amounts of rainfall on the basis of a temporary observation network designed so as to serve special users. Several peculiar features of rainfall were made clear in the typical functional expressions in Japan.
Lastly, a new regional c lassification of Japan was systematically tried by synthetic comparisons and considerations of computed statistical quantities by use of annual and monthly rainfall data through significance tests applied to actual statistical results. The final classification arrived at is slightly different from the traditional climatic classification obtained by the several representative climatologists.

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The heat and moisture suppl i e d from the warm sea surface are principally transferred upward by the predominant convective activity. Basing on the aerological observations over the Japan Sea coastal region, the convective transfer is estimated by the residual computation on the thermodynamic and the moisture continuity equation applied to some selected situations of the prevailing northwesterly winter monsoon.
The convective transfer is expressed in terms of conve c t ive updraft, excess temperature, convective Bowen's ratio and the area ratio of the updraft column. Therefore, the characteristic value of the area ratio may be inferred by evaluating the other parameters. Introducing the information obtained by a serial dropsonde observation, we can show a reasonable value of the area ratio.
Predominant convective h eat transfer together with the release of latent heat results in a temperature field such that the air column in the cloud layer is heated up towards downstream.

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This paper deals with a syno p tic investigation of the three-dimensional motion in a cut-off cold vortex over and in the vicinity of the Japan Sea during the period 21-24 January,1963. This particular situation was selected for study because the cut-off cold vortex brought about heavy snowfall over the coastal area of the Hokuriku District, Japan. It is found that the vertical circulation pattern on the east side of a cut-off cold vortex is characterized by a direct circulation and that on the west side by an indirect circulation. In addition, it is shown that the schematic model proposed by PALIIIN and NAGLER (1949) is actually observed in the case of a cut-off cold vortex. An attempt is also made to clarify the energy conversion process of this system. It is concluded that the energy conversion process of the cold vortex can not be treated as a closed system as was done in the past, but must be considered as an open one. The contribution of the vertical circulation to its process is discussed.

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Compared with Japan and E ngland (including Wales), the United States shows a noticeable slowing-down in the seasonal variation of overall mortality in recent years for all age groups, particularly babies under 1 year. When this phenomenon began to appear and what process it has undergone will be studied in this paper on the basis of vital statistics in the past three decades for the City of New York.
Not until the 1940's did the slowing-down of mor t a lity variation come to the fore in the City of New York for babies under 1 year,1-4year old infants and old age people over 70 years. On the other hand, little change was seen in the meantime in the seasonal variation of mortality for able-bodied groups from 20 through 50 years, for which mortality has hardly varied from season to season in the preceding decades. The recent moderation of mortality variation by season means, in fact, the steady flattening of the winter peak, which resulted for the most part from the remarkable decrease of deaths from such infectious diseases as influenza, pneumonia and tuberculosis, particularly for infants who showed a winter maximum in the 1930's but a nearly straight curve in the past two decades.
It must be noted, in this connection, that before the 1930's there had been a mortality mode in summertime as well as in the cold months in the United States as observed by some American statisticians. Higher mortality in the hot months had come mostly from gastro-intestinal diseases. But this had disappeared by the 1930's thanks to the improvement of public health services and regulatigons, the improved handling and processing of provisions, the pasteurization of milk and other foods, and the wider use of refrigerators.
The disappeara n ce of the summer mode was followed by the rapid flattening of the winter peak, which is to be ascribed to the ever wider adaption of central heating as well as the notable improvement of medical techniques and services and the marked betterment of general living conditions.
In the 1930's, though central heating was widely adopted in the City of New York, the seasonal variation of mortality was fairly high for oldage people and infants probably owing to the prevalence of pneumonia, bronchitis, tuberculosis; etc. Deaths from these diseases appear to have curved up in the cold months to form a peak. After World War II, however, the winter peak levelled off year after year because deaths from pneumonia, tuberculosis, etc. decreased rapidly thanks to the everwider use of sulfa drugs and antibiotics and the effective adoption of central heating. The favorable effect upon infancy of the artificial climate created by central heating must be highly appreciated.
This study in the slowing-down of mortality variation by season in the United States has urged the writers to reconsider their previous concept of “mortality concentration in winter with the progress of human culture” from a wider point of view. In England, no summertime peak was seen as early as the 1800's, while the mortality curve climbed up, though slowly, in the cold months in recent years. This is a new subject worth studying with utmost care. The seasonal variation of mortality in the past 10 decades might well be summarized as follows:
The mortality peak has shifted from summer to winter for Japan; without any maximum in the hot months, the winter peak has been getting steeper for England; and the death summit itself, though it has moved from summer to winter, has got so flat as to indicate a possible “deseasonality” of mortality in a long perspective.

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It of ten happens that we ob s erve the wind direction by means of natural objects such as tree branches and reeds which are flexible or deformable. The present experiment is conducted in the wind tunnel to see the change of oscillation mode of a wind vane with a hinged free flap of various chord lengths, which simulates the deformability. The results are expressed as the change of oscillation period and damping ratio, which shows the degradation of motion as the deformability increases. Also the effect of flexibility is considered qualitatively.

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A spectro-pyrheliometer, wh i ch is composed of a telescope, a double monochrometer, an amplifier and a recorder, is designed for the measurement of the solar and the sky radiation. The opening angle of the telescope is so small that the sky radiation from the small sky area whose angular distance is one degree from the center of the sun, is measured without any intervention of direct solar radiation. The monochrometer used is the one with two quartz prisms.
The photomultiplier EMI 9526-B is used to detect the light in the range from 0.3 to 0.8μ, e of wavelengths, and the PbS cell is used in the range from 0.65 to 2.0μ. The intensities of solar and sky radiation comming from the small area whose angular distances are 1,2,3,5,7,10 and 15 degrees from the center of the sun and from the zenith, are measured.
By the measurements of direct solar radiation, we obtained the optical thickness at each wavelength and infered the content and the size distribution of the aerosol particles in the atmosphere. The spectral value of the photocurrent corresponding to the extraterrestrial value of solar radiation at each wavelength is deduced with the Bouguer-Langley method. This is the calibration constant of the instrument which is used as the unit of any measured value, and then the absolute values can be obtained. The spectral intensities of the sun's aureole in units of the extraterrestrial values have the order of 10^-4 to 10^-6.
The optical thickness and aureole intensity a t each wavelength obtained from the measurements are compared with those obtained by FOITZIK, V OLZ, BULL1110EanCd others.

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