In a previous paper, the author dealt with the problem of solar radiation over the earth's urface assuming no atmosphere existed. The earth we live on is, however wrapped in a blanket of gas through which the sun's ray penetrate, gradually decreasing its intensity. Therefore, radiation conditions become more complicated and the previous study becomes only a rough approximation, utilized in order to simplify mathematical analysis of the problem. If the actual features of solar radiation were greatly altered by the existence of the earth's atmosphere, the previous study would be without practical value. In such a reason an approach toward the actual earth is ernestly schemed. This paper consists of two parts; the following subjects are discussed.
Part 2. Meridional distribution of solar radiation over an atmosphere-covered earth.
1) Quantity of radiation over the earth as a whole.
2) Total amount of radiation on selected days at every five degrees of latitude.
3) Total radiation during selected intervals at every ten degrees of latitude.
Part 3. Meridional distribution of effective radiant energy.
Part 2
Together with the quantity of radiation received all over the earth (Table 1. ), the daily amount of radiation coming through the atmosphere with the transmission coefficient p=0.6 and 0.8 on twenty-four selected days is computed by graphical integration. For determining the area on the graph, Simpson's formula is used instead of a planimeter because it has proved more accurate in a tentative study. Assuming the meridional curves of daily radiation (Fig. 1) to be parabolas, the latitudes with maxium amounts are obtained on shirteen representative dates. A portion of the results are shown in Table 2. Similarly, the total radiation coming through the same atmos-phere during the selected intervals of time and latitude with their maximum amounts are calculated in the same way and shown hn. Table 3.
Part 3
The previous studies are restricted to incoming solar radiation, but, at the same time, the earth and its atmosphere send out long wave radiation to outer space. Therefore, the effective energy utilized is the difference between them, the incoming radiation subtracted from the outgoing. On these quanti-ties, Simpson, Baur and Philipps have made studies considering the effects of cloud reflection and sky radiation and computed the amounts at every ten degrees of latitudes in both hemispheres. After Simpson's data, meridional distribution of effective energy in June, July and August is shown in Fig. 4. From the above study, it is quite clear that the total amount of radiation during the growing season is always greatest at latitudes 30°_??_40° and in the long run, is nearly equal to that on the earth with no atmosphere. This is an important fact and its geographical meanings described in an, earlier paper are completely verified.
It is concluded that the climatic superiority of the middle latitudes is due not only to the moderate temperatures and plentiful rainfall throughout the year, but also to the abundant solar energy concentrated during the shorter intervals of the growing season.
The author is obliged to abandon concrete description and merely add the numerical tables of results for economy of space. The details of the whole work will be given out after further study in the near future.

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I. One of the fundamental problems in climatology, the typical patterns of air-temperature was investigated applying the method of factor analysis as follows:
_??_
where the common fa, , tor is Fs (s=1, 2, …, m) and the unique factor Uj. Fs and Uj submit to N(0, 1) and are independent of eanh other. As data for the analysis, the mean monthly temperatures of January, April, August, and October for the period 1901 to 1940, at twenty-five weather stations in Japan were utilized. Initially, factor Fl was calculated and secondly, the factor F₂, thereafter, finding the remaining correlation coefficients insigni-ficant, further calculations were abandoned. The coefficients of F₁ and F₂ for the four months are shown in Figures 1 to. 4. Generally, the coef-ficients of F₁ are very large throughout Japan, showing values ranging between 0.7 and 0.9 while the coefficients of F₂ are smaller and vary a great deal by districts. Analyzing the variances in the data by the three way lay-out, Table 1 was derived. The variance of coefficienss by lands (L) and by factors (F) are significant while that by seasons (S) is insignificant. The interaction term of L×F is significant, but those of LxS and F×S are insig-nificant.
II.hogically, the next step is a consideration of the kinds of common factors controlling air temperatures in the months under study. The first factor is one which has a great influence over a vast region, Judging from the fact that the coefficients of the first factor commonly show large values throughout Japan. It may be considered to be one as vital, as the general circulation of the atmosphere. As the second factor, may be considered a function of latitude, such as solar radiation, judging from the fact that the coefficients. of the second factor are arranged in order of latitude from north to south. The correlation coefficients between the coefficients of F₂ and the solar radiation in three of the months are very large and significant, showing 0.834 in January, 0.923 in August, and 0.870 in October, while that for April shows only 0.362. From this fact., it appears that solar radiation is a primary factor in the distribution of air temperature.
III. From the results of the factor analysis of air temperature in April, Japan may be divided into two large areas, the north and the south (Figure V). In order to further divide these areas, factor analysis of air temperature was again attempted. Two subdivisions for each area were obtained and are shown in the figure as Areas ff 1 and If 2 in southern Japan and 11 and 12 in northern Japan. Tius Japan may be divided into four climatic divisions by the two factors F1 and F₂ when it is considered that two common factors control the distribution of air temperature.

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1. The organic content of lake deposits has been determined for 53 Japanese lakes.
2. Loss on ignition: In the fresh water lakes of harmonic type, the pereentage of loss on ignition ranges from a minimum. of 8.4% in Lake Kutarako (Oligotrohpic type) to a maximum of 21.0% in Lake Toroko (Eutrophic type) with a mean of 14.5%. The dystrophic pons have the highest, as would be expected, from 336.2% to 60.8%.
3. Carbon and Nitrogen: As we detected in general a negligible amount of carbonate-carbon in common lake deposits of Japan, it is probable that the carbon constitutes essentially organic matter. Excluding the dystrophic lakes, the amount of carbon varies from a minimum of 1.5% in Lake Shinjiko (Eu. Brackish) to a maximum of 8.6% in Lake Toroko. The amount of nitrogen falls between 0.15% in Lake Shinjiko (Eu. Brackish) and 1.04% in Lake Haruna (Meso) and shows a good parallelism with that of _??_ the mean ratio of Nitrogen to Carbon being 0.116.
4. Ether extract ranges from 0.28% to 1.50%.
5. The lakes have been divided from the standpoint of biological produc-tivity, and have been further divided on the basis of transparency and. salinity. So far as we have determined, it seems that there is no marked difference in the organic cotent of deposits in the lakes.
The assumption that the eutrophic lake deposits may contain much organic matter is not always true. The typical oligotrophic lake-deposits certainly have a smaller amount of carbon and nitrogen, but the content of organic matter in some eutrophic lake deposits are as small as in the oligotrophic lake deposits.

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