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 projects which general prosperity cncourages, if it does not create, and which general distress forces people to abandon.

The change from arid to semiarid climate at the southern end of the Desert of Atacama takes place in a very narrow belt of country about Vallenar. In the Vallenar district there is a distinct rainy season that extends from May to August. June and July have commonly the greatest rainfall: three heavy showers and it is called a very wet year. But the fact that rain may be depended upon to come practically every year gives a stability to ranching and valley farming which is not enjoyed at Copiapó and places farther north. At the time I visited it, in mid-July, 1913, there had been no rain whatever, and it was said that this was the first year in twelve that the drought had been so prolonged and the third year in succession that no substantial amount of rain had fallen. Yet this is only a day's journey from Copiapó where rains are not de- pendable at all and where instead of one dry year in twelve there is more commonly but one “wet” year in twelve (cf. Fig. 14).

The heaviest rains in the wet years at Vallenar produce damage as great as at Copiapó. When all the mountain ra- vines have running water the main stream, the Huasco, rises to a great height and gnaws away the lower terraces and the edges of the flood plain. In 1906 and 1907 there was high water, and in one period so much damage was done to the valley lands that the land had actually to be resurveyed and reapportioned.

Unlike the narrow and small irrigated tracts about Copiapó, the Huasco valley at Vallenar is covered with green. The whole floor is populated for fifty or sixty miles upstream, and many of the terraces are irrigated and covered with green al- falfa fields. In the midst of them stand the ranch houses, spa- cious and prosperous-looking in contrast to the small huts of the smaller farms on the valley floor. Above and below the city are “shut-ins,” or narrow places in the valley, so that the town appears to be in the bottom of a vast bowl and, when seen from above with its great expanse of alfalfa meadows