Page:The Music of the Spheres.djvu/302

 slight mastery over the heat, and by cooling the earth's film was continually shrinking thus forming a thicker and more solid protective crust. After an heroic struggle between these mighty forces the crust was at last strong enough even to sink down in places to fit the inner core; the sea then ran into these hollows and into the wrinkles formed from the shrinking, and the first ridges or islands appeared above the surface of the water.

These ridges or islands were then attacked by the elements, eroded by the weather and the rains, and the granite which formed them was crumbled into quartz, feldspar and mica. The torrents of rain formed rivers, and these, seeking a level, carried the débris down to the shores of the ridges,—the finer sediment, the feldspar and mica, being washed far out from the rocky land where it settled to the bottom of the sea and in time formed mud-banks, which under pressure turned to clay, while the clay under greater pressure, turned to slate. The quartz of the granite, ground to fine particles, stayed near the shore and formed sandy beaches, which if covered under great pressure, became sandstone. Thus were some of our various rocks formed from the original rock of granite, and no matter where one sees sandstone or claybanks, even if on top of a mountain, such a place was once under water, for that is the only place where such sedimentary material could form.

This slow disintegration of the earth's first land continued for millions of years, the waste accumulating along the shores, and as far out as the finer sediment could be carried. Finally the pressure on the edges of this land caused the thin crust to soften and break, the molten magma poured forth in great masses, and the thick sediments were smashed together, folded up and thrust