CLIMATE OF NORTH AMERICA HUNTINGTON. 395 



indicate where ntiiis would be found. Accordingly I decided upon 

 the head of the Rincon Valley, about 22 miles southeast of Tucson, 

 as a test case. The expected ruins were found in the shape of several 

 small villages, the cliief of which contains the foundations of at least 

 18 houses. Probably there were once other houses in the valley, 

 for pottery is found in several places where no foundations are visible. 

 The present })opulation consists of two Mexican and two American 

 families, one of the latter being the forest ranger; but the arable 

 land is said to amount to 150 or 200 acres, which would j^ermit of a 

 popidation of 20 or 25 families. The significant fact in this case is 

 not the discrepancy between the present and past population. The 

 number of inhabitants in the past was not limited by the amount of 

 water available in the stream, but by the amount of level land in the 

 narrow bottom of the valley. Apparently the Hohokam wanted 

 more land than they could readily obtain. About a mile and a half 

 east of the forest ranger's house and some 3 miles east of the promi- 

 nent hill called Sentinel Butte, a grassy slope drops toward the 

 northwest at the base of Rincon Peak, 8,465 feet high. The slope 

 has a fall of about 10 degrees, and an altitude of from 3,300 to 3,500 

 feet above sea level. On the most favorable part of the slope, for a 

 distance of about half a mile parallel to the upper Rincon, and for a 

 width of half or two-thhds as nuich, one finds unmistakable terraces 

 built apparently for purposes of agriculture. In general they are 

 from 20 to 70 feet long and 2 or 3 feet high. The commonest location 

 is at right angles to the minor drainage lines, each little swale being 

 broken into terraces with a width of from 20 to 30 feet. In some 

 cases the spaces between the swales are also terraced, the terrace 

 walls in all cases being composed of pebbles and cobblestones. I 

 searched carefully for pottery, but succeeded in findmg only one or 

 two coarse bits, quite in contrast to the abundant potsherds which 

 occur not only among the foundations lower down the valley, but 

 along the borders of the alluvial plain. The only other works of 

 man among the terraces are some small stone circles, like th(^ beds 

 where the modem Indians cook the yucca to make the drink known as 

 mescal, and a low round structure of bowlders. The whole hillside is 

 almost exactly like hundreds in Palestine, Syi-ia, and Asia Minor, or 

 like others in Mexico and South America. Even the little round 

 structure, about 7 feet in diameter, with its small doorway, suggests 

 the watchmen's shelters in the terraced fields of S}Tia. There can 

 scarcely be any doubt that the teixaces were designed for agriculture. 

 Apparently they were not intended for irrigation, for they are not 

 properly arranged for this, nor does there appear to be any available 

 source of water. They must have been intended for dry farming. 

 Three or four miles down the valley, near the main village, a few simi- 



