The sea! the sea! the open sea! The blue, the fresh, the ever free! Without a mark, without a bound, It runneth the earth's wide regions round. From Barry Cornwall Sailors talk about "the seven...
The moving continents
It may seem to you that the earth's crust is a single piece of rock. You may think this crust covers the outside of the earth just as an apple's skin covers an apple. But the earth's crust is...