26. When a Cannon keeps attacking a Rook, disregard whether the
Rook is protected or not, even if the Rook doesn't move and both
sides only move the cannon mount, it is a perpetual chase. (See
examples in Diagram 61 and 62)
Diagram 61: Red (in Capital) moves first
Diagram 62: Red (in Capital) moves first
In Diagrams 61 and 62, the Red Cannon moves the Guard or Minister to
perpetually chase the Black Rook. Red has to change the move.