THE RUINS OF SOUTHERN ARIZONA. 57 



opposite side. If Charco Yuma West of the Mountains had existed at the same time as 

 Charco Yuma East of the Mountains, the same necessity for protection must have existed 

 in both cases. Hence it seems probable that the western and larger village was abandoned 

 in favor of the eastern at a time when protection against enemies had not yet become a 

 vital necessity. The western village is more favorably located than is the eastern with 

 respect to agricultural lands, such as those of Rillito or the rest of the Santa Cruz Plain, 

 but it is not so sheltered as the other, nor so near to the river bed, whence water was pre- 

 sumably derived. If a progressive diminution of the water-supply had anything to do 

 with the matter, the supply of the lower village would fail before that of the other; for 

 the village east of the mountains is located where the level of permanent underground water 

 is at a depth of a little over 20 feet, and a slight rise would bring it within reach of the 

 surface; while in the bed of the river adjacent to the western village the ground-water 

 level is at a depth of 50 feet or more. The greater abundance of pottery in the western 

 village, the greater depth to which it is buried, the greater degree of weathering of the 

 wall of the temple inclosure, and the absence of all defensive structures on the hills suggest 

 that the western village dates from an early time, presumably of peace and prosperity, 

 while the eastern village dates from a later period of greater stress and danger. If the 

 same line of reasoning is pursued farther, we may infer that the absence of a genuine fort 

 at Charco Yuma and the presence of such structures at Tucson and San Xavier indicate 

 that in course of time conditions grew still worse, so that the outlying town at the Point 

 of the Mountains was abandoned, while the upper towns began to seek the protection of 

 regular forts. The abandonment of the lower town may have been due to desiccation and 

 the consequent failure of the crops, or to the growth of warlike tendencies among the 

 neighboring peoples. 



In offering these suggestions we are venturing upon the realm of theory rather than of 

 proven fact. The justification for this lies in the fact that among Asiatic ruins of similar 

 character, in the deserts of Chinese Turkestan and elsewhere, written records prove that 

 the villages were abandoned one after another, beginning far downstream and progressing 

 upward. Further comment on Charco Yuma is unnecessary. Its population was appar- 

 ently almost as great as that of Jaynes; it was inhabited for a long time, and its people 

 must have required much water both for drinking purposes and for the irrigation of fields. 

 The supply available in the vicinity to-day is hmited to floods in wet seasons and is often 

 entirely lacking for many months, sometimes for over 2 years at a stretch. No trace of 

 reservoirs has been found, and no reservoir which could be built in this flat, dry region could 

 retain water more than 5 or 6 months, as is proved by modern experience in more favored 

 localities. The arable land is limited to .300 acres, and even this small tract often fails to 

 produce a good crop. 



Seven miles below Charco Yuma, or 24 miles down the Santa Cruz from Tucson, 

 Mr. W. J. Wakefield showed us a small ruin located about 0.7 mile due north of Nelson's 

 Desert Ranch. It is over 3 miles from the dry bed of the Santa Cruz, and 3 miles from 

 the lower end of the strip of arable land which begins at RiUito Station. The level of 

 ground water is so low that in digging a well at the ranch it was necessary to go down 

 182 feet. This is stated on the authority of Mr. Wakefield, who lived here as a boy 

 and whose knowledge of this region and others, both in Arizona and Mexico, was most 

 kindly put at our disposal at much inconvenience to himself. At the ruins near Nelson's 

 Ranch the water-level must be still lower than at the ranch. A few small "washes" 

 lead occasional floods down from the Tortollitas Mountains some miles to the north, but 

 there is absolutely no hint of any permanent water-supply. The ruins consist of a rec- 

 tangular inclosure, 210 by 175 feet, with the long side running N. 25 E. magnetic, or N. 

 37 E. true. A wall of earth, now almost obliterated, surrounded the inclosure and was 

 pierced at the southern corner by a gateway. In the opposite, or northern, corner a 



