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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The author surveyed the landform of marine terraces under 400 m along the coast of Hidaka to analyse chronological relationships between Erimo volcanic sand and the formation of terraces.
The terraces may be classified as follows:
Pleistocene
Level-I (upper erosion surface) : mostly destroyed by erosion
Level-II (middle erosion surface) : mostly destroyed by erosion
Level-III (lower erosion surface) : mostly destroyed by erosion
Level-IV (upper marine terrace)
Level-V (lower marine terrace, upper river terrace)
Holocene
Alluvial terraces
Alluvial plain
These surfaces were mainly formed by transgression and regression repeated in the Pleistocene. There were two glacial stages lowering the sea level, namely Poroshiri and Tottabetsu ice-stages. In the author's opinion, Level-IV and Level-V of the Pleistocene surfaces are correlated with these two glacial stages.
The development of landforms in this region is summarized and correlated in the table 3.

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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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