Several men join together and build a wall of rocks and timber two feet high in the form of a circle about 15 metres (50 feet) across. This wall is made open so that the water will run through as the tide ebbs away. On the top of this wall is a heavy net 1 to 1.5 metres (3.5 to 5 feet) high, made of coarse twine, supported by long pilings driven into sand at the base. They are held in position by the stone wall with an opening on the upper side toward the beach, also with long arms running back toward the shore for as long as 100 metres (330 feet). This is made so that the fish running against this fence 12 metres (40 feet) high and lined with this heavy net will be unable to go any farther in this direction, and will naturally swim along this netting toward the sea until they come to the opening in the enclosure, and will swim into the cage, without a clue that they are swimming into a place where they can never return to the ocean. The tide then ebbs away leaving them in a pool of water about 45 centimetres (18 inches) deep. Then one man stands in the centre of the pool with a scoop net, and another man with a pole will walk around in the pool and drive the fish into the net. Every twelve hours this pool fills up with all kinds of fish.