The New Student's Reference Work/Quicksand

Quick'sand (quick, i. e. living or moving sand), a tract of sand which, without differing much in appearance from the shore of which it forms a part, remains permanently saturated with water to such an extent that it cannot support any weight. Quicksands are most often found near the mouths of large rivers. They appear to be formed only on flat shores, the layer of earth under the sand being stiff clay, which water cannot pass through; and in narrow channels, through which the adjoining shore from its shape causes strong tidal currents to run, the sand may be kept so constantly stirred up by the moving water that a quicksand results. Quicksands are not commonly of great extent, and their danger has probably been exaggerated in the popular mind by sensational descriptions in works of fiction, as in the Bride of Lammermoor and in Moonstone.