The river Nogawa is a tributary of the Mogami. As the Nogawa flows from the snowy Asahi Mountains, it gets melted snow until June. The temperature of the water is very low, and is unfavourable to the rice. Being a rapid stream it often causes serious damages of the floods. For the multiple purposes of raising the water temperature, protection from floods, and at the same time to generate hydro-electricity, Yamagata prefecture constructed the dam Kanno in April, 1954, and the dam Kijiyama in November, 1960.
Based on the data of the observation of 30 years by Mr. Shibuei Shibuya, Nagai-shi, the author compared the water temperatures before and after the construction of the dams. Concerning the water temperatures of August, which is important to the rice crop, the average of ten years before the construction of the dam Kanno is 21.7°C., and the seven years' average after its building falls to 18.0°C. After the building of the dam Kijiyama, the average of the four years is 18.6°C. Accordingly, the drops of 3.7°C. and 3.1°C. are noticed. So, in order to find the cause of the fall of the water temperature, the author made a research about the distribution of the water temperatures at the dam lakes Kijiyama and Kanno.
The dam lake Kijiyama has not a device to collect the warmer surface layer water. So it takes the water from the depths of 11.6 meters to 14.0 meters below the surface, the temperatures of which range from 16°C. to 18°C. This water, then, flows into the dam lake Kanno, but, as the two-thirds of this lake is like a river on account of its deposits of earth and sand, its water temperature does not rise much. As to the dam lake Kanno, although it is devised to collect the surface water from to the depth of 4 meters, it gets sometimes the water 12 meters below the surface, the temperture of which is 16.0°C.
In conclusion, in order to raise the water temperature, it is necessary that the dam lake Kijiyama should have a proper device to collect the warmer surfaec layer water, and that the one at the dam lake Kanno should be improved.

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At the time of heavy rainfall, very humid air named “moist tongue” is found in the upper air levels over Japan. This air, extending as a tongue from a moist air to the west or to the southwest, has been repeatedly observed during the rainy periods. In this paper, the moist air area around Japan was analyzed statistically from the vie wpoint of dew-point distribution during the baiu season (June and July). The observed frequency of dew-points above 6°C., 8°C., 10°C., and 12°C. indicates that between the 1st and the 10th of June in the average of three years, 1960-1962 (Figs. 1-4) the axis of the moist area lies in South China and extends to the east; and that between the 1st and the 10th of July (Figs. 5-8) the axis lies in central China and extends to the east. Each group of figures for June and July shows that the core of the moist area exists approximately in SW China with its axis moves toward the north in the early summer when the baiu frontal zone moves toward the north.
The observed frequency of high dew-points is shown in Table. Analyzing each observation, the authors conclude that the “moist tongue” appearing over Japan emanates, in many cases, from the above mentioned moist air area.

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Bearing capacity, on the surface and subsurface horizon, is a factor deciding the trafficability of bulldozers, tractors, combines and other such heavy equipment. By statistical analysis, the author investigated the relationship between the bearing capacity and the soft grounds of alluvial areas in the Kanto plain, the Tsugaru plain, and the Sarobetsu plain. In this paper, the bearing capacity is calculated from the average of the results that are measured at each point, 0 to 50cm. deep, by cone penetro-meter. Asa result of his investigations, the author comes to the following conclusions: 1) The bearing capacity is different for alluvial fan areas, natural levee areas, and delta areas in the Kanto and the Tsugaru alluvial plains. 2) Except alluvial fan areas, the standard deviation is from 13 to 15 in both the Kanto and the Tsugaru alluvial plains with a normal frequency distribution at each area. 3) Except of surface soils, the bearing capacity shows the same change for every area made up of silt, clay and peat. 4) The plowpan (Sukidoko) horizon, lying under the Ap horizon, causes the difference in bearing capacity between natural levee areas and delta areas. 5) Where land is made up of silt and clay, the standard deviation is the same, so the relationship between the number of survey points for bearing capacity survey and the allowable errors to the sample mean can be accurately delimited (the Y-N Curve, Fig. 4) .

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In Akita, Yamagata, and Niigata prefectures, various damages were caused by the Niigata Earthquake occurred at 13:02 June 16, 1964 with its epicenter near Awa Island. To know the influence of this earthquake on the landslide areas, the author made recon-naissance survey in the landslide areas of the southern part of Niigata prefecture and of the northern part of Akita prefecture. 1) In the southern part of Niigata prefecture where various types of landslides frequently occur, such landslides were not caused by this earthquake, while various miniature disturbance of the ground, for example, cracks several meters deep and several centimeters wide were brought about ; the groundwater table are lowered. 2) On the rear mountain slope situated at a once slumped part in the northern part of Akita prefecture, the author found a newly-formed scarplet with a throw of 10 to 20m and a length of 0.8km (Photo) .

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The relations of some conspicuous families in Isawa-gun, Iwate prefecture are traced back to the mediaeval age. They were of local importance, and their houses have some common characteristics such as moats and embankments and often made nuclei of village agglomerations.

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Nowadays, in Tagajo-machi and the eastern part of Sendai city urban areas expands as the result of increased urban landuse diverted from arable land, due to the development of manufacturing industry. The authors made a research on the diversion of landuse in the areas along the National Highway 45, the main road from Sendai to Shiogama. The farmers who gave up their arable land for diverted landuse also changed their farm management. Following five types may be classified in this change: 1) The farmers who enlarged their farm land, by purchasing more land with money gained from the sale of a part of their land. 2) The reduction of the area of the farm land due to the purchase of arable land smaller than the land sold. 3) The farmers who lost in the acreage of their land as the direct result of the sale of the land. 4) Landowners changed from farmers who lent a part of their land reserved from the sale. 5) People who abandoned farming after selling their arable land and were engaged in other works. Generally, the farmers lost in the acreage of their farms. However, some farmers increased their land by means of the purchase of arable land larger than the conveyed land. Consequently, the scale of their farms is largely different one another.
Most of the diverted land is used as residential lots. 77 percent of those who obtained the diverted land, settled in Tagajo and Shiogama, and many of them are engaged in the secondary and the tertiary industries, especially in retail sale business and as government employees. Considering the former dwelling-places and occupations of the people who took over the diverted land, it seems that the development of the urban use in Tagajo is not the direct influence of the development of Sendai city.
On the other hand, in the eastern part of Sendai, most of diverted land is used as factory- and warehouse-sites, and this is different from the case in the rest of Sendai city where diverted land is ordinarily used as residential lots and school sites.
Thus, the type of diversion of land from arable to urban use is different in both areas, in Tagajo and in the eastern part of Sendai. There is a contact area of the two types of the diversion, the formation of which may mean the process of conurbation. The landuse in this area will change into more intensive ones, such as the secondary and the tertiary industries or at the same time into residential lots.

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Muroran-Tomakomai district is one of the main industrial districts in Hokkaido. Many factories are distributed in Muroran-shi and some are located in their adjacent areas. The larger factories among them are Fuji Steel Plant, Nihon Steel Plant, Oji Paper Mill, Kokusaku Pulp Factory, and Daishowa Paper Mill. The medium and small factories are rather few. Recently, chemical, ceramic, and lumber industries are growing in this district marking an epoch in the industrial development of Hokkaido.

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Recently, the motor vehicle traffic rapidly developed in medium and small cities as well as large cities. In this report, the author analysed the pattern of the motor vehicle traffic of medium and small cities in Tohoku district. Principal sources are results of the “origin and destination survey” which practiced at 12 cities in 1962.
In urban area the motor vehicle traffic is classified into three patterns as follows : the first pattern named intra-urban traffic, which both origin and destination lie in urban. According as size of city become large, the proportion of this traffic to urban increase and clearly forms the traffic region in medium cities whose 200, 000-500, 000 populations, for example Sendai, Aomori, and Akita. This traffic concentrates in urban center, commercial, business, and railway station area. Traffic volumes become rapidly to dicline in proportion to the distance from urban center. The automobile traffic regions are small, but the truck traffic regions are larger and dispersive. The second pattern, urban-suburban traffic which origin or destination lies in urban and suburban. This traffic shows mainly a truck movement. The third pattern, through traffic which both origin and destination lie outside of urban. In small cities there are so many through traffic compared with all traffic, but through traffic volumes make little difference to it in medium cities.

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For the modernization of Japanese agriculture, it is indispensable to cut the number of farming households, and to enlarge the average size of the farms several times. According to the analysis made of a NW part of Nagano prefecture, however, the number of farm households in rural area has shown a decrease neither in 1950-55, nor in 1955-60 period. If the trend can be generalized to the whole of the nation, it would be difficult to expect the success of the current government program of the modernization of agriculture.

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Two seamounts on the northern part of Kyushu-Palau Ridge were explored by the Takuyo Expedition in August 1960. These seamounts stand abruptly about 1500m above a swell rising about 2000m gently from the Philippine Sea Basin with a NNW-SSE direction.
One of them, the Komahashi Seamount appears to have an uneven top which has its peak at the depth of 500m. The peak of the other seamount, the Takuyo guyot, is conical with a distinctly flat top 3.7 kilometers wide. There is a distinct break in the slope around the Takuyo guyot at the depth of about 700 meters. Apparently this seamount is a wave-truncated submerged volcano like the guyots on the Mid-Pacific-Mountains.

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Fukushima basin is composed of alluvial fans covering lake deposits. Mesuring the depth of the water table in wells, the author obtained the following results.
The ground water flows from the west to the east and nourishes the Abukuma. The distribution of the ground water table is generally parallel to the surface topography. Two ground water valleys are found, which are buried valleys of the paleo-Sukawa. Influent seepage of the Matsukawa is important as the source of ground water and springs at the ends of fans.

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The authors surveyed pH and temperature of the surface water in the Goshikinuma and other lakes on 24th July, 1964. The results are compared with figures from the former surveys in 1931, 1935, and 1937 by S. Yoshimura (Tab. 1) .

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