These heavings and twistings, these crumplings and swayings, of the earth-crust do not belong only to land, but go on in the same manner under the ocean. Many an earthquake felt on land has its origin under the sea; and others are so far out as to be felt only by passing ships. In the Pacific alone it is said that about two thousand five hundred shocks occur in the course of a year. Of the eight or ten thousand shocks, believed to be about the average number throughout the world annually, fully half have their origin beneath ocean-waters.
CHAPTER XIII.
OLD OCEAN AS A BUILDER
“Grain by grain His Hand
Numbers the unmeasurable sand.”
C. G. Rossetti.
“... The ever changing strand
Of shifting and unstable sand
Which wastes beneath the steady chime
And beating of the waves.”—Whittier.
AS a vast Cathedral is made of separate blocks of stone, laid one upon another and cemented together, so a stratified rock is formed of tiny particles of substance, placed one over another and pressed into solidity.