SUMMARY 



407 



PART OF THE PLAIN OF WATERLOO, 

 BELGIUM. 



men can easily be assembled. Military stores can be 

 readily collected and all the operations of war carried on 

 without natural obstructions. Thus it happens that cer- 

 tain plains have been the 

 seats of almost innumer- 

 able wars. The great 

 plain of the Tigris and 

 Euphrates was the gath- 

 ering ground and bat- 

 tlefield of vast ancient 

 monarchies. The plains 

 of the Po have been the 

 arena in which embat- 

 tled Europe has settled 



some of its deadliest strifes, while the level lands of Bel- 

 gium have been dyed again and again with the blood of 

 thousands and thousands of Europe's bravest sons. 



Summary. Level areas are called plains when low, 

 plateaus when high. When a coast has been elevated 

 and part of the continental shelf becomes exposed, this is 

 called a coastal plain, as the east coast of the United 

 States from New York to the Gulf of Mexico. 



Coastal plains have little mining and manufacturing ; 

 their agricultural products vary. Their large cities lie 

 either at tide water or at the fall line of the rivers. The 

 best drinking water on coastal plains usually comes from 

 artesian wells. 



Besides coastal plains there are lake plains, like those of^ 

 northern New York and eastern North Dakota, and 

 river plains, of which the Mississippi is the best example. 

 The prairies have a fine, rich, treeless, fertile soil, a result 

 of ancient glaciation. The great plains of the United 

 States have an irregular surface usually barren of trees. 



