CLIMATE OF NORTH AMERICA HUNTINGTON. 399 



constructed numerous reservoirs, however, and these were their main 

 dependence in the dry season. One such reservoir still remains 

 intact at Gran Quivira. It lies about a quarter of a mile cast of the 

 village in the mouth of a shallow arroyo, as dry valleys are here 

 called. The reservoir is only about 75 feet in width and 5 feet deep. 

 The owners of the ranch down below in the main valley say that 

 during seven years of life here they have never seen any water in it 

 excel) t immediately after rain. My visit took place in the early 

 spring of 1911, after a more than commonly rainy season. The day 

 before I started from the railroad at Willard, 30 miles to the north, 

 there was a heavy storm, and during the drive we were soaked in a 

 pouring rain. Nevertheless the next morning the reservoir con- 

 tamed no water and showed no sign of having had more than a small 

 pool in it the day before. In all the region within a score of miles of 

 Gran Quivira there is only one permanent spring. That is located 7 

 miles to the west at jMontezuma, and, as might be expected, it has its 

 own ancient village. Strangely enough, however, the Montezuma 

 village was apparently abandoned long before Gran Quivira. This 

 suggests that the difficulty of raising crops was a more serious matter 

 than the difficulty of obtaining water. At Montezuma the land does 

 not lie so low and flat as at Gran Quivira, and is not flooded as are 

 the lowlands of the latter place during summers, when the rainfall is 

 unusually large. In considering these places the point to be borne 

 in mind is this: We have before us two theories, which stand on an 

 ecpial footing as to innate probability. The only question is which 

 one best fits all the facts. One theory is that the climate of the past 

 three centuries has been uniform, while the other is that the seven- 

 teenth century was considerably moister than the nineteenth, and 

 that the eighteenth century was intermediate between the other two. 

 Viewing the two theories without prejudice, the theory of change 

 seems to fit the facts better than the theory of uniformity. Hence 

 we may tentatively conclude that the seventeenth century was a 

 period of relative humidity, although both the preceding and succeed- 

 ing centuries may have been comparatively dry. 



The other two periods of relative moisture may well be discussed 

 together. One of the most strikmg examples of a former abundant 

 ])opulation in a region now almost uninhabited is the Chaco Canyon 

 in the northwestern corner of New Mexico. It lies just to the west 

 of the wooded crest which forms the continental divide in this por- 

 tion of the great southwestern i)latcau. As soon as the wooded area 

 is left behind one comes out ui)on a barren treeless plateau at an 

 elevation of 6,000 or 7,000 feet, a dreary region where one may ride 

 25 miles at a stretch without seeing a smgle habitation. The only 

 inhabitants are a few nomadic Indians of the Navajo tribe and a 

 handful of white settlers. The Indians and a few of the white men 



