east of Iquique. Yet where these stands of bush occur it is just as much a desert as the nitrate pampa, where there may be no vegetation at all.
Definition of the Desert
Those who have studied the Sahara and also the deserts of our Southwest have always remarked the relative abun- dance of vegetation in our deserts. A desert has become by definition not naked sand or rock but a place of small rainfall with a sparse and specialized plant and animal life. The point is worth making here, because upon a number of maps published before 1860 the term “The Great American Desert” was written over the western part of the Great Plains of the United States, over plains, valleys, and basins alike, where later exploration and settlement have shown a dependable water supply, a large acreage of irrigable land in the aggre- gate, and even local forests.[1] Because such settlement and exploration has steadily pushed back the borders of the American desert, it is sometimes supposed that the word “desert” can be discarded entirely and that we can look upon the whole of our vast public domain in the West as land that will some day be made habitable. Only those who mix pa- triotism and rainfall can envisage so rosy an outcome. As a matter of fact, we have an extensive area, as truly desert as the Sahara or Atacama—thin or meager vegetation, highly adapted in its resistance to drought through the narrowness and hardness of its leaf surfaces and its resinous protective epidermis, scattered scttlements, extensive tracts without vegetation or human settlements, strong contrasts between day and night temperatures, excessively high midday tem- peratures, and a rainfall of but a few inches a year.[2]
Except for those places where mountain streams flow out upon the piedmont border there is no vegetation to speak of in the Desert of Atacama between the basin floors at two
