1. A shallow bashin-like topography (“ Waju-chikei”): The three rivers, that is, the Kiso, the Nagara and the Ibi run reticulately at their lower courses. The residents around those rivers have constructed the embankments in a circular form, talking advantage of natural levees. As at the center of each protected low land is a back marsh, it makes a shallow basin-like topography. The writer gives a name to this unique topography “Waju-chikei” (encircled topography). Its soil is a fine one. As the rivers deposit their silts in the restricted foreland, so the level of a latex closed land is higher than that of a formerly closed one.
2. Sequence of its land utilization: Every paddy-field in the back marsh had once been cultivated, but as the time passed by the level of the encircled topography became so low compared with that of the foreland, that it could not drain water at all. Therefore the residents were obliged to construct a canal for draining, and laid the soil obtained from it upon another paddy-field. It was done about 1840 A. D.. But unfortunately the productivity of the paddy-field could not be recoverd. In the Meiji period, however, the three rivers were separated, and with the in vention of a draining machine, the productivity of the back marsh field came to be fully displayed and the canals were gradually reclaimed. Even at present time its topography still has some effect upon the land utilization of this district.

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The example above is found in the lowland valley formed as the result of the erosion of a diluvial table-land in the Kwanto Plain. The lower part of the valley consists of thick formation of peat, and the upper part, of soil. The former has become paddy-field relying upon the water supply by rain alone. In view of the fact that these paddy-fields have been under satisfactory natural irrigation, they mast have been reclaimed since old times. At the beginning of the Tokugawa Era (namely the Tensho Period), we may suppose, there had been farms near the paddy-fields that is, around the valley and also some houses in the neibourhood. Since the Tokugawa Era, about half of the villages gave moved to the table-land to the west, simply because new farms have been reclaimed, there.
The reason why the villages are considerably conservative is due to the fact that the conditions of the arable land, especially its location, its area, its methods of irrigation and of cultivation have not been changed since long ago. The basic cause of the above fact is that the valley has beer favoured with sufficient wetness from rain water, though there is no stream available.

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The truck transportation concentrated in the metropolis of Tokyo has remarkably developed lately. Within considerable distances from Tokyo trucks have overwhelmed freight trains in goods transportation.
The author has studied from the data on the kinds of goods and their carried distances, obtained from investigating 6, 155 trucks coming into and going out of Tokyo during just one day frm 10 a.m. on May 5, 1950 to 10 a.m. on the next day. According to its investigation, the truck transportation areas of Tokyo are divided into five. They are as follows:
1. The suburban area (10-60 kilometers). Within this area a truck driver can return to his base early enough to do his works of the next day. This area is a sphere within which the truck is superior to the train whatevera condition may be.
2. The middle distance area (60-150 kilometers). Within this area it takes one day including the times both for loading and unloading for the truck to reach over there. The daily fresh provisions such as vegetables, fruits, milk and meat area are transported profitably by means of truck service, within this area. But in general this area is a competitive zone between trucks and trains.
3. The long distance area (150-300 kilometers). As this area is beyond one day's reach, the driver has to put up for the night on his way or to make a through-night driving and it is hard to get the chance of acquiring the return loads. Therefore the freight rate in trucks becomes higher than that in trains.
4. The areas out of limits in far distances (more than 300km). Beyond 300 kilometers it becomes very difficult to operate the trucks economically from theoritical and practical point of view. This is a monopolistic sphere for the activity of the freight train.
5. The area out of limits in short distances (less than 10km). Within 10 kilometer circle trucks can not work effectively. In place of trucks, bicycles or carts work much more profitably.

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Nearly simultaneous measurements of the water temperature were carried out 13 times on every 21st from Oct. 1930 to the same month of the next year at the river Chikuma (the upper half of the river Shinano flowing in Nagano Pref. is so named). The writer selected 18 bridges built at irregulra intervals on the Chikuma and 3 on the river Sai, the largest tributary of the former, and asked his acquaintances (most of whom were the teachers of primary and middle schools) residing in the vicinities suited to do this job. The mercury thermometer, the bulb of which was tightly covered with 15fold gauzes, was plunged into the water about 2 feet deep for 10 minutes, when it was quickly pulled up to be read within one minute. It must be added that this measurement was performed only within one hour from 8 to 9 o'clock a.m. till Feb. 1931 and later on be tween 7 to 8 o'clock a.m.
Tie figure is the profile of the Chikuma, in which the numerals indicate the localities of the bridges and the water temperatures measured ar edotted. The broken lines connecting them. The figure shows that the water temperatures are almost uniform throughout the river during winter 4 months.
There is even a slight tendency to decrease in its Temperature as the river flows downwards in its severest month, when the influence of springs at the upper part of the river is obvious. Therefore the temperature gradient of the river is very small. In summer, however, the water becomes outstandingly higher as the river runs down, the most characteristic type of the season being shown in August.
The river Sai starts from the Matsumoto Basin where the numerous and voluminous springs at the edges of the continuous alluvial fans adjacent to the precipitous east slope of the Japanese Alps are the main water sources of the river, which meanders incisedly through the Sarashina Hill.
The Sarashina Fill lies between this and the Zenkoji Flat and flows into the Chikuma at a point about 2km downwards from No. 13 in the latter depression. On account of the abundant supply of water from these spring-sin the Matsumoto Basin, the annual fluctuation of the water temperature in the Sai is less. That is, during summer season, the water temperature of the Sai is cooler than that of the Chikuma, while, during winter season, the temperature relation between two becomes reversely. One can easily find this interesting contrast in comparison between No. 13 of the Cikuma and No. 19 of the Sai, the latter being nearly 5km upwards from the joint of these rivers and only within a few kilometers from the former.

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