15 



natural boundary line between the two geological systems 

 here brought together. 



It is now believed that the sedimentary rocks, the ends of 

 which are now exposed to our view along the eastern side of 

 this valley, must have extended very much farther into the 

 mountains, and that after "the elevation of their mass they 

 were partly removed by erosion. The thickness of these 

 layers is given by Dr. Hayden's surveys at 7000 feet. 



From the consideration of these general features let us 

 turn our attention to the various phenomena as seen when 

 travelling along between the granite and the sedimentary 

 rocks. No one can obtain an adequate idea of the wonders of 

 this famous strip of country until he has seen it for himself, 

 and it would be hopeless for us to attempt a description that 

 would fully convey the impression produced by these master- 

 pieces of the work of erosion. We shall therefore be con- 

 tent with the scientific part of the description, leaving the 

 imagination to fill up the blanks. 



The Front Range is really broken but once below Denver 

 by a deep canon, where the Platte rushes from the South 

 Park through this narrow path to the plains. Below this 

 point, on the road to the south, we cross the low divide which 

 separates the Platte from Plum Creek, and soon descend 

 into the valley, whose curiously carved monuments, of which 

 we will speak below, make it so attractive. 



About half-way between Denver and the Garden of the 

 gods we find the divide which separates the waters of the 

 Platte from those of the Arkansas. This slight elevation of 

 a little over 1000 feet above Denver controls the flow of the 

 tributaries of those streams until they reach the open plains 

 to the north and south of this point, when they take the direc- 

 tion of the long gentle slope to the east. To the south of 

 this divide these monuments increase in number until the 

 Garden of the gods is reached, which owes its name to the 

 grand display of these singular objects at that place. 



These monuments seem to have been formed in several 

 ways, principally, however, by erosion ; these isolated parts 

 have been left because they were either of harder material 

 than that surrounding them, or more able to resist meteoric 



