GENERAL EEPOET. 



2' 



Nortll, 



Vertical Scale 1 inch to 5000 feet. 



South. 



In the above profile, vertical proportions only are closely observed. 

 The southward slope is well made out. I have taken, so far as possible, 

 representative altitudes. 



1. South Park, on Platte River, Colorado, altitude 9,000 feet. 2. 

 Trout Creek Divide, 9,350 feet (approximate). 3. Granite on Arkansas 

 River, 8,883 feet. 4. Puncho Pass, 8,945 feet. 5. Saguache, on the head 

 of the Rio Grande, 7,723 feet. 6. Bacon Spring, near Fort Wingate, New 

 Mexico, 7,189 feet. 7. Port Wingate, 6,982 feet. 8. Zufii Mountains, rather 

 a plateau than mountain-range, with an altitude of seldom, if ever, over 

 9,000 feet. 9. Zuni, on the head of Zuni River, 6,355 feet. 10. Willow 

 Spring, 7,195 feet. 11. Camp Apache, 5,000 feet. 12. Tanks south of 

 Camp Apache, 5,624 feet. 13. Gila River, 18 miles east of San Carlos, 

 2,769 feet. 14. Camp Grant, 4,833 feet. 15. Tucson, 2,400 feet (approx- 

 imate). 



Of course, as a rule, along any given latitude there would be an 

 eastern or a western slope also, as this line is not far from the meridian 

 of the continental axis. An absolutely north and south line would give 

 somewhat different figures, but would nevertheless illustrate the same 

 truth. 



Intimately connected with this slope of the continent to the south is 

 the geographical distribution of the forest growth. It appears that the one 

 factor of all others in the problem as to what shall be assigned as the lowest 

 limit of timber, is the lowest point on the plain to which sufficient moisture 



