Generally speaking, as Japan is a rainy and mountainous country, she is blessed with abundant water-power resources, which are now considerably exploited for generation of electricity. But before the Industrial Revolution, to be exact before 1892 when the first hydroelectric-power station was built in Japan, water-power had been used only on a small scale by water-mills scattered throughout the country.
The author, who is studying water-power utilization in Japan from a standpoint of historical geography, recently found one rare old list of water-mills of Nara Prefecture, which had been compiled from the official investigation in 1881, and may be called “the census of water-mill”. The items of investigation are as follows:
(1) the name of site where a water-mill was situated,
(2) the name of stream or ditch on which a water-mill was constructed,
(3) the date of construction,
(4) the name and address of the owner,
(5) uses (…e.g. rice-cleaning, flour-milling, oil-pressing, cotton-ginning, spinning and the rest),
(6) distinction between commercial and private use,
(7) the diameter of water-wheel.
This list, containing 556 water-mills which existed in Nara Prefecture in that year, tells us, through these items, the distribution of water-mills, the purpose of water uses, the degree and the process of water-power utilization and so forth. As the first part of the author's analysis, the distribution and the process of construction of those water-mills were studied (The Faculty of Letters of Nara Women's University: Annual Report of Studies in Humanities and Social Sciences, Vol. IX, 1965). In this second article, the variety of functions of these 556 water-mills is discussed.
Most of these water-mills-393 of the total-were used for rice-cleaning, and this fact means that rice-cleaning was the main purpose of water-power utilization in those days. They scattered every sixth village on an average, gathering in some villages and dispersing in others. In Nara Basin, where the yield of rice was abundant but the sites of water-mills were restricted, they were owned by specified people and were used for business. While on Yamato Plateau, where the outturn of rice was not so much as that of Nara Basin, but the water-mills were distributed densely, they were jointly owned by villagers and were employed in rotation for private use.
Other water-mills were used for the manufacturing of special products which were manufactured at that date in Nara Prefecture. Materials of some groceries, such as Japanese vermicelli and frozen bean curd, were prepared by these water-mills, and rape oil or cotton-seed oil were also pressed by them. Cotton-ginning and spinning also asked water for these motive power.

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The main contents of the present paper are concerned not only with geographical techniques to select the suitable area for housing estate from the point of view of the comparative cost of construction works in different locations, but also with the time and money distance required when residents go to work.
Both topographical and geological factors are the most important of all natural ones that bring local differences to construction expenses The former exerts an influence upon the cost of site development, and the latter upon the cost of foundation works. The relation between these factors and construction cost is as follows: Topographical factors…The site development cost occupies a high rate in all the constrruction expenses for housing estate, and varies largely by local differences. Such local differences depend mainly upon the conditions of initial relief of the site. Accordingly we can replace relief of topographic feature by site development costs. To the consideration we must clarify how to express relief of topographic feature, and the correlation between relief of topographic feature and land reformation costs:
1) We divide a development area into 100 meter sections on the topographic map of a three-thousandth, and regard the arithmetic mean of the total summing up the difference between the highest point and the lowest point within each section as the average relief energy of topographic feature.
2) The relation between the average relief energy of topographic feature and land reformation costs per unit area is as follows (refer to Fig-1):
The classification of relief of topographic feature viewed site development costs. Average relief energy of topographic feature (m/ha) Site development costs per unit area (1, 000yen/ha) The remarks column 2> 100 The flat area which does'nt require banking. 2< about 700 Pleistocene terrace whose initial surface remains mostly. 21> 3.000> Pleistocene terrace whose initial surface is almost losed. 21< 3, 000< Heavy slope area.
3) There is a high correlation between the average relief energy and the number of contour lines within each 500 meter section on the topographic map of a fifty-thousandth in the same area (refer to Fig-2):
The correlation is 0.98, the formula of regression line is
y=0.17x+0.87.
Using the techniques mentioned to above, we made the map of relief of topographic feature in Nagoya Metropolitan Area (Fig-3). From this map, we can know that housing estates have been developed on the alluvial plain, the Pleistocene terrace and the hill where the number of contour lines above mentioned is less than 2∼4. However it is expected that the large scale housing estate will be developed on the hills of 5∼7 contour lines where land value is comparatively low and there are lots of vast common lands.
Geological factors……It may safely be said that we can classify to a certain extent local differences of foundation work expenses in accordance with geological areas in Nagoya Metropolitan Area. Then we made the distribution map about local differences of pile length and forms of foundation work in Nagoya Metropolitan Area (Fig-4). The result is as follows:
1) Plio-Pleistocene upland…On cutting site 3∼5 story apartments are constructed without foundation piles. But in development area we have to construct buildings on banking site, so 30∼50% of apartments need foundation piles. Consequently, the adding cost of foundations is 120∼250 yen per floor area (m²).
2) P ocene terrace and alluvial fan……As the surface is plane, there is no need of site development. We construct 3∼5 story apartments without piles.
3) Delta plain……Generally 5∼10 meter prefablicated piles are used to reach the apex of the pile to the upper sand layer in alluvium, so the adding cost of foundations is 600∼1, 400 yen per floor area (m²).

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