Abstract
It had been found that the water supplied in a newly-build school house in M District in Gifu City was a little astringent, and formed greese like membrane on standing, which became cloudy by boiling. The source water of the supplied water proved to contain much of erosive free carbonic acid, which cause the dissolution of Ca, Mg from asbestos pipe, and Zn from zinc coated iron pipe into the supplied water. This phenomenon has been observed for more than 3.5 years since the beginning of water supply. The influence of feeding mice and golden fishes by the supplied water on their growth and living time were also observed.
