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ELEMENTS OF GENERAL SCIENCE 



It is believed that the whole gorge, seven miles in length, 

 was formed by the recession of the falls. When the river first 

 began to flow between the lakes, it fell over a cliff that runs 

 parallel to the shore of Lake Ontario, the falls being located 

 near the present town of Lewiston, New York. During the many 

 centuries that it has been flowing, the falling water has been 

 wearing away the head of the gorge and thus lengthening it. 



FIG. 83. Niagara Falls 



At Niagara the river falls into the head of a narrow, steep-walled gorge. The 

 gorge has been made by the river 



The rock which formerly occupied the present position of the 

 gorge has not only been broken loose, but most of it has been 

 worn into sand and gravel, which has been carried to the lower 

 stretches of the river or into Lake Ontario. Many hundred 

 tons of rock have thus been loosened and transported a long 

 distance by the water of this river. There are many other 

 rivers which have transported much more material than the 

 Niagara River has. 



