48 THE FOURTH ZONE. 



slopes of the Rocky Mountains, when we may gaze ujjwards 

 at the lofty snow-covered peaks above our heads. Hence, 

 crossing the mighty range in spite of grizzly bears and wilder 

 Indians, we descend towards the bank of the Rio Colorado, 

 which falls into the Gulf of California, and thence over a 

 mountainous region, some of whose heights, as Mount Dana, 

 reach an elevation of 13,000 feet, and Mount Whitney, 

 15,000 feet. 



THE FOURTH ZONE. 



The southernmost of the four zones begins on the coast of 

 Florida, passes for hundreds of miles over a low or gently 

 sloping country toward the gTeat western plains which border 

 the Rocky Mountains into Texas ; its southei-n boundary being 

 the Gulf of Mexico. Through this region flow numerous 

 rivers, the queen of which is the Mississippi. The western 

 portion is often wild and barren in the extreme, inhabited 

 only by bands of wild and savage Indians. The Rocky 

 Mountains being passed, there is a lofty table-land, and then 

 rise the Sierras de los Nimbres and Madre ; beyond which, 

 bordering the Gulf of California, is the wild, grandly pictur- 

 esque province of Sonora, with its gigantic trees and stalactite 

 caves. 



