Footprint sculptures. Among relics of undetermined use and significance left by the vanished tribes are numerous representations of human footprints, often regarded as actual footprints made while the rock material was still plastic. They are sculptured in slabs or masses, generally of sandstone, and show a varying degrees of skill in execution. Representations of tracks of men and beasts also occur frequently in pictographs painted and sculptured on rock surfaces. In this connection they probably served to designate particular creatures or beings, the direction of their movements, the number of individuals, etc., but the larger well-sculptured footprints represented in museum collections probably had special significance as the reputed tracks of ancestors, of giants, or monsters, and may have been designed by cunning persons to deceive the uninitiated. The carvings represent sometimes a single footprint and again two or more in association, and are usually shallow, being rarely more than an inch in depth. Consult Rau in Smithson. Cont., xxii, 22, 1876. (W. H. H.)