Nine experiments with 2-inch waves breaking for 24 to 48 hours on a beach of pebbles and sand produced cusps in eight cases. Seven runs produced continuously changing cusps; the last run, after two hours, produced cusps which remained stable for 24 hours. The stable beach was analyzed for size and shape sorting in area and depth. There was no significant difference in size sorting between cusps and bays. The most spherical particles concentrated at the foot of the beach, the platelike ones at the back of the bays, and the cusp points were a highly permeable mixture of plates and tetrahedra; this is consistent with transport up the beach by suspension and down the beach by dragging and rolling.

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