Page:The Music of the Spheres.djvu/327

 rim are imposing as they fall across its plain. Aristillus is about 34 miles in diameter, and 10,000 feet deep. In the center of this deep cavity rises a massive many-peaked mountain whose base is often lost in the darkness of the crater's shadows. Autolycus, south of Aristillus and somewhat smaller, is 23 miles in diameter with a floor somewhat depressed below the country which surrounds it.

On the "shore-line" of Mare Imbrium, north of Archimedes, Aristillus and Autolycus, and not far from the "Valley of the Alps," lies Plato, one of the most easily found craters on the moon. Plato is a very huge oblong crater, 60 miles in diameter and containing an area of 2,700 miles. Its floor