68 Rapids Lakes. 



rocky arid sloping, the water rushes down vio- 

 lently and rapidly. Such parts of a river are 

 called rapids. (See rapids in the chart.) 



The St. Lawrence River contains the celebrated 

 Lachine (Zah-sheeri) Rapids. 



36. A lake is a body or collection of water 

 which is formed and fed by one or more rivers ; 

 these are called its inlets. The water of most 

 lakes is fresh ; some lakes which have no out- 

 lets or outflowing streams are salt. 



37. The largest fresh water lakes in the world are those 

 between the United States and the Dominion of 

 Canada ; their names are Superior, Huron, Michi- 

 gan, Erie, and Ontario. Great Salt Lake is in Utah. 

 Observe from the chart that some lakes are on low and 

 others on high ground. 



38. Lakes and rivers are very useful in many 

 ways ; people sail on them to different parts of 

 their State or Country, and on them they send 

 and receive all sorts of things, such as food, 

 clothing, and building materials, very easily and 

 cheaply. On account of these advantages peo- 

 ple have built cities, towns, and villages on or 

 near the banks of rivers and lakes. 



39. This buying, selling, and trading between people of 

 different States or Countries is called commerce. Com- 

 merce is carried on also by way of railroads and canals 

 and the great ocean or sea. (You will learn about canals 

 in Chapter VIII.) 



