Chigiri is the method that we use butterfly-shaped wedge to prevent both of two things made of stone or wood from detaching. We can see two iron wedges in the different directions here. That is why they keep stones of the top of the wharf from falling down, The wave has washed them for a long time, so we can find just the marks.
Akashi heritage-map “castle town(Jouka)” 2017
Exist without change
