The aim of this study is to develop data base system dealing with digital map data. A case study is made concerning railway route data connected with relational data base system for historical indexes. Referince is made through the relational data base system and graphical presentation is displayed on the CRT screen by BASIC program. Several observations were obtained on the articulation of railway data.
In Japan, before river improvement works began from the age of civil strife wars in the 16th century, people had been allowing free floods on alluvial plains. It was construction of embankments in the river improvement projects that had gradually thrusted floods in river ways. In modern ages, embankments had become higher and stronger. Therefore, general people at present have naturally thought that rivers don't overflow their banks. Nowadays, if once we allow floods from rivers, it may cause heavy damages. In Japan, it is said that the river improvement works by using high embankments to protect cultivated lands against overflow have begun since the Kyouhou period (1716-1736) in the Tokugawa era. Nowadays, we can understand Water use and Control technologies at that time from literatures of the Tokugawa era. In order to know the change of river improvement methods of those days, we have tried to find out development of embankments in the Tokugawa era by using these existing literatures.
Historical data were analiesed for evaluation of the 1742 flood at the Chikuma River in Japan. From the corps damage ratio data at 18 villages along the Chikuma River, the maximum flood heights were estimated at each villages. These maximum flood heighs were plotted and maximum flood stage profile was g i ven. Th i s estimation was verified by flooding marks. Nax i mu m flood discharge total flooding a rea and volume were calculated from this profile. Then, it i, vas clearfied that the 1742 flood at Chikuma River was the higgest one in 300 years and had heavy rainfall area at right tributaries of the upper Chikuma River.
The Tatsumi-canal is a remarkable monumental work in the history of Japanese water supply canals, and was constructed by Hyoshiro Itaya, the conductor in 1632. This paper is primarily concerned with the technological aspects of the Tatsumi-canal. The hydraulic technologies, channel excavation technologies, water conveyance pipe system and pipe manufacturing techniques adoped for the Tatsumi-canal have been reviewed and discussed. The Tatsumi-canal is relatively well preserved, and thus most of the parts are still operational in the original manner. It is, however, suggested that details of the technologies adopted for the Tatsumi-canal are not sufficiently known. Thus, the further study, especially for the parts extended in 1837 and 1855, respectively, is recommended.
This paper describes the past and present state of railway tunnels, based on field surveys and historical records. In this second report the objects selected are the former Kyoto Ry. and Hankaku Ry., which were constructed to link Keihanshin district with Maizuru area in the 1890s, and the structural features of the tunnels on these railways are made clear here. These two companies were established with similar intentions, in similar periods, on a similar scale; later purchased by the National Railways of Japan, and now the greater parts of the lines have discontinued services upon completion of new lines. These tunnels are found very valuable as monuments to brick or masonry structures of the Meiji Era.