The coin shape stonework measuring 1.65 meters long, 1 meter wide and 20 centimeters deep could also be used to pool water with its drain being connected to the turtle head.
小判形石造物は長さ1.65m、幅1mで深さ20cmで同じく水が貯められるようになっており排水口は、亀の頭に繋がっている。