The Japanese don't leave any land lay waste and and presume it has all been under cultivation for many centuries. At Tokyo one of the large canals was flanked by great stone walls five height of 25 or 30 feet, the stones used being lava upon andesite lava. They were else rough lava rocks no mortar being used & the stones being irregular but well fitted. The walls slanted inward as as at a slight angle as with lava walls. The wall rocks used is andesite practically no other was seen, In some of the lengths the flooring was of white granite. The wooden pilings don't teller wooden posts plentiful, were alight red like our Cal. Redwood apparently the Cryptomeria tree.