Since the rapid economic growth in the 1960's, with an increased demand for cement, the tendency to use fresh concrete and transport in bulk has increased. This tendency has resulted in the development of seaside plants and shipping transportation, and in an increase of seaside Cement service stations as transit bases. On the other hand, the growth of inland plants and Cement service stations which rely on railways, tends to have stagnated. That is, since the character of cement is only minimally suited to freightage, a seaside plant is more lucrative than an inland plant in the respect of transportation. As for the areal trend of cement, transport is mainly from Chugoku and Kyushu, where excess cement is produced, to Kanto and Kinki area, and the distributing area of a seaside plant is wide compared to the narrow inland plant's area. An example of the distributing range of the Tokai area can be illustrated by seaside Cement service stations which are supplied from distant areas, mainly Chugoku and Kyushu, and inland Cement service stations, supplied from a nearby area within 50km to 150km. Areas to be distributed differ according to makers. The makers who use seaside Cement service stations mainly supply in a wide range. Makers can be divided from a view-point of sales area into nationwide makers and local makers.
The former plants are mainly seaside and their production is large. The latter plants are mainly inland or smalloutput seaside plants with a few plants in either location.

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Since some prefectures do not announce the number of employees officially, the writer estimated them by size of factory measured by the number of workers (employees and family workers) in the period of 1970-1972, using regression between workers per factory and employees per factory. Estimation was judged useful when the maximum value of|c|was less than 0.05, where c=d/y, d is confidence interval obtained on condition that confidence coefficient is 95% and y is estimate. Due to this criterion, usefulness of estimation was found in the factory groups of above 20 workers, above 10 workers, above 4 workers and all workers.

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In order to clarify the climate by year fluctuation of climatic condition on the Nansei Islands, the year climates were studied in comparison with the climates by the normal values. Formosa, the region around the Yangtze river mouth, and southern Kyushu are also included in the study for making clear the local differences of the Nansei Islands.
The year climates based on the Köppen's climatic types reveal the differences clearer than the climates by normal values. Namely, Cwa appears to the north and south of the Cfa area, all over the Nansei Islands. The difference between humid and dry areas by the year climates based on the Thornthwaite's climatic types range widely as compared with the climates by normal values. The Nansei Islands are relatively humid in contrast to the surrounding areas. This can be explained by the Pacific Polar Frontal Zone which locats over the Nansei Islands in winter. In spring and autumn, on the other hand, there occurs frequent cyclogenesis on East China Sea and the cyclones move along the Nansei Islands. The different dry conditions by years has stronger effect on the Thornthwaite's year climates than the annual evapotranspiration. The water deficiency based on the year climates appears at the all stations. The amounts of the water deficiency are larger south of Okinoerabu Island than north. Especially, the areas at the northern part of Formosa, on the coast of the continents, at the southern part of Formosa and around the Minamidaito Island are the driest. When the middle latitude high pressure prevails strongly in summer, the dry conditions occur over southern part of the Nansei Islands.

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It is said that Japan has a short dry period in mid-summer. However even in such a period, the local rainfall is frequent in some regions. The author clarifies the distribution of such a local rainfall during the short dry period, using data for precipitation in Fukushima Prefecture and Northern Kanto area (Fig. 1).
The results are summarized as follows;
1) The local rainfall in mid-summer is often observed along the north borders of Tochigi Prefecture. This area does not always coincide with the region abundant in total summer precipitation (Fig. 3).
2) As a whole, the local rainfall in mid-summer occurs during 1600-1800 JST, and it tends to stop within two hours (Table 1), but each station has a different characteristic in hourly occurrence (Fig. 4). In the northwestern Tochigi Prefecture, the local rainfall in mid-summer inclines to occur in the earliest time (Fig. 5 and Fig. 7).
3) The ratio (%) of amount of precipitation in the dry period of mid-summer to that of total summer precipitation is highest, about 20%, in Yamizo Mountains, Tadami area, and around Kiryu (Fig. 9). The ratios fluctuate considerably year-to-year, and in some case, they exceed 50%.

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From the 4th to the 7th of August, 1979, the active “Bai-u” front passing through Iwate Prefecture in Northeast Japan brought about a heavy intermittent rainfall and it caused inundation disasters along the main stream of the Kitakami River. The damage by the inundation amounted to over 11 billion yen the whole prefecture.
The inundation brought about two types of damage along the main stream of the Kitakami. One of these is directly due to the rising of the Kitakami, which caused a flood over a wide area, stagnant for a long time. This type of damage typically occurred at the lower reaches of the Kitakami Basin, especially in the Ichinoseki area.
The other type is inundation disasters on account of the countercurrents of tributaries and the unworkable draining of channels. Such damage is rather artificial in that the residential sections have been constructed in marshy areas of flood plains, back swamps and abandoned channels. This type of damage typically occurred in the Hanamaki area.
Considering these damages by inundation disasters, the writers will point out some important problems as given below concerning the development of the Kitakami River.
1. The dams constucted at the tributaries drain off to control the water level of their dam-reservoir during a heavy rainfall. This raises the water level of the main stream of the Kitakami. The heavier it rains in the drainage of tributaries, the more damage is caused by inundation disasters along the main stream. In Constructing dams, we need to consider the balance of the water level of all the drainage basins.
2. We can appreciate the value of the “Yusui-chi” project in the Ichinoseki area (“Yusui-chi” means a land for pooling flood water). It should be kept in mind secondary inundation disasters such as the countercurrents of tributaries of the flood through the unworkable draining of channels may be caused by the construction of artificial embankments.
3. The more urbanization progresses and the more residential sections are formed in marshy areas, the greater damage of inundation disasters will occure. It is therefore necessary that the local public bodies consider how to keep off such disasters.

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