PHYSICAL GEOGEAPHY. xxxv 



f{^(£c(IIaTii] g crossed, by tlie soutliern mouutain boundary of 

 for the^^'^^^ Park into the eastern main chain, tbe continental 

 i^ l)#ide lies now on tbe eastern side of the." Summit Plateau," 

 g242t only througli 1*^ ; it then crosses again from Long's 

 jgiijak to the western chain, forming three sides of a 

 lare, enclosing the next park. Middle Park, which, of 



ve 



.arafflie 



.•IllgggU'se, is di-ained by streams flowing west. These streams 

 ,u^^^ the head- waters of Grand Eiver ; they escape through a 

 i jjjft in the western main chain, and, uniting eventually with 

 sen Eiver, form the Great Colorado of the West, 

 jf ho next section of the '' Summit Plateau " is South Park ; 

 s hemmed in on all sides, like the other parks, by moun- 



llinioiis 

 [eratioff 



«j 



1 j^^ns, the eastern and western main chains being well defined. 



•i^g^e continental divide traverses the northern and westerrb 

 nges which bound the park. The drainage is collected 



,-,^to two streams, and passes through the other two sides 

 . ':at througli the eastern forms the south fork of the Platte, 

 ■|^hile that which escapes through the southern becomes the 



^ j-kansas Piver. 



a; South of South Park the two main chains of the Eocky 

 . iountain system are never again united by transverse ranges, 

 ', ..ut diverge very considerably, as may be seen by referring 



'fl the map. In the fork thus formed rise the head- waters of 

 ; Jie Eio Grande, and as the ranges diverge, so does the valley 

 ^ )f this important river widen out. High up in the fork the 

 Summit Plateau" is called the St. Louis Park, and with 



ts crystal streams, its corn-fields, and its lake abounding in 



'.rout, is well deemed the most beautiftd of all the Parks. It 



''' s no less than 7,500 feet above the sea; the mountains 



"joundiner it on the east are called the SieiTa Planca, and 



^ hose on the west the Sierra de San Juan. 



Gradually the ^'Summit Plateau" widens out, and sinks 



c2 



i 



