The Mighty Deep 



about one ton ; and some mighty billows are 

 known to batter with a weight of three tons. 



Such a fierce assault as this, continued through 

 thousands of years, might well in time wear away 

 the hardest rocks, demolish the loftiest cliffs. 



A counteracting force, however, exists, and has 

 already been named. Our earth-crust is in 

 motion. Parts of it are sinking, and in those 

 regions the ocean has the best of the contest ; 

 for fight as man may, raise walls and bulwarks 

 and breakwaters as he will, he can but retard the 

 inevitable. If the sinking continue, no matter 

 how sluggishly, he must in the end be beaten, 

 and the persistent sea will encroach upon the 

 land's domain. But many coasts are slowly 

 rising, slowly lifting themselves out of the sea, 

 slowly shaking themselves free from Ocean's 

 dominion ; and in those regions, no less in- 

 evitably, the action of the sea is thwarted. 



As to the why and the wherefore of such 

 Crust-movements, science suggests explanations. 



Once upon a time, long ago, our Earth was 

 a glowing molten mass. Since that period it has 

 been cooling, and it .is cooling still. Many facts 

 point to the great probability of a still molten 

 centre. 



Not only do we find volcanoes scattered over 

 ii6 



