On March 9 and 10, 1961, the writer surveyed the condition of the snow cover in the catchment basin of the artificial Lake Yonezawa under project, with an area of 67, 37 square kilometers. For the survey, the basin was divided into five divisions, A, B1, B2, B3, and B4.
The snow cover was stable in the first decade of March, 1961, and the amount of water in the snow cover did not appear to have increased or decreased. In this period, without much change of the density of the snow cover, from a place to another, its depth is proportional to the amount of water contained. Therefore, the relation between the depth of snow cover and its water content is shown as a straight line in the diagram.
But, in Division B3, the observation data were markedly scattered, and in Division B4 no definite relations were interpreted. In Division B3, regarding the densities of snow cover on March 1, March 10 and March 30, the density obtained on March 10 is remarkably smaller than the others. This means that the sampling in Division B3 and B4 on March 10 was not satisfactory, making the data less trustworthy.
The density in Division A equals to that of the snow melting period, and is too large as a value in the stable period. This may be due to the fact that either the density was shown greater than its real value because the balance did not work well, or that the snow samplers were weighed less than the real weight, or due to both.
In Divisions B1 and B2, the line which represents the relation between the depth and the amount of water in the snow cover is drawn as a combination of a convex curve and a straight line, although this form of a line is not too common. The present writer, therefore, rectified this into a straight line parallel to the line in Division A.
As regards to the interval between the lines representing the relation of the depth of snow cover with the amount of water in it in Division B3, on March 1 and March 30 respectively, the smaller the depth of snow cover, the greater its interval, and the greater the depth, the smaller its interval. The line on March 10 must lie between these two lines, and the line which fits in this part is the rectified one of Divisions B1 and B2. This was rectified again, so that the interval between the lines of March 1 and March 30 should be proportionate to the number of days between these dates. The line thus obtained is the standard line which is to be used to convert the depth of snow cover into the amount of water in it.
As regards to Division B1 and Division B2, the value of the actual measurement of the amount of the water in the snow cover using snow samplers is compared with that of the amount of the snow cover converted using the standard line. The results are as follows. In Division B1, the calculated value is smaller than the actual value by 70 millimeters at its maximum depth, and by 3.8% in amount. In Division B2, the former is smaller than the latter by 80 millimeters at its maximum depth, and by 5.0% in amount. If there exists such a proportional relation between the depth of snow cover and the amount of water in the sonw cover as in the other snow covered areas, the difference between the actual measurement value and the calculated one ought to be much smaller.
Therefore, if an exact observation is to be made in a typical course which has a straight line relation between the depth of snow cover and the amount of water in the snow cover, it would be sufficient to make a survey of the depth of snow cover only. Then we sholud be able to cut radically the number of persons and the survey expenses, without lossing the efficiency.

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日高沿岸の洪積世後半の地形面は、関東平野の地形面と関東ロームとの関係と同様に、襟裳火山砂をkey bedととして分類対比する事が出来る。この洪積火山灰の有力な手がかりである降灰年代を参考に、上述の調査結果に基づいて本地域の地形面を、Pd. Dlr、Dlrr、Dur、Durr、Ar、Arrに分類した。又本地域の地形発達の概要はTable 3に要約されている。
日高氷期と関連づけて地形発達を考えているので、eustatic movementのあつた事を想定しているが、その量的問題については今後の研究によらねばならない。

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What are the regional factors deciding the discontinuity of the frequency of the train operation? In order to find out this, I calculated the coefficient of frequency versus the mileages of the railway section, and computed the relative weight of the regional factors by the Sequential approximation method.
The following nine factors are what I have pointed out as regional factors: Population (1: the rate of industrial population, 2: the rate of commercial population, 3: the rate of service population, 4: the rate of occupation population), 5: sight seeing, 6: section of operation of passenger, 7: points of transfer, 8: control of train operation, 9: the distance from the starting station.
Each of the nine factors above mentioned is divided into three and by the Sequential approximation method the weight of the factors was calculated. Thus it was found out what regional factors caused the discontinuity in the train operation.
In coefficint, the factor due to the different ways of the operation shows the highest figure, followed by those of the points of transfer, and topographical obstacles. Among factors, more such of the technical nature of train operation are influential, than those due to the character of the population.

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