350 



THE COLORADO DESERT 



not subside for many decades. The volcanoes are doubtless imme- 

 diatel}' due to the infiltration of water from the Colorado overflow 

 down to the heated beds of rock not far beneath. Converted into 

 steam, these waters burst violently upward through the deposits of 

 silt, and around their orifices throw up encircling walls of mud. The 

 heated condition of the rock formations below the surface would seem 

 to be due to the great delta accumulations here, and would seem to 

 support the mechanical theories of the origin of crastal heat. 



COCOPAH WINTER HuCSE ANU BASKET (iRAXAltlKS — WITH l.llilX GKOWIXl 

 IXVXDATED BY OVERFLOW 



OS liROlXU RECENTLY 



From a photo(/raph bi/ the author 



Throughout the desert the inundated countrv produces a most 

 astonishing growth of grasses, wild hemp, and weeds. A variety of 

 tumbleweed (Chenopodium) grows to a height of ten feet in a few 

 weeks' time. For months of the summer thousands of acres of the 

 so-called desert are transformed into luxuriant meadows. The Coco- 

 pah Indians, who live along the right bank of the Hardy, as well as 

 on sloughs further east and on the lower Colorado itself, raise abun- 

 dant crops of maize, beans, and melons from the naturally irrigated 



