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on tinder, particles of any supposed caliche are brought in contact with a strip of burning cotton wicking. or mecha. If nitrate is present, the particles ignite sharply, and with no further test an expert can tell approximately the percentage of nitrate present.

The nitrate is so readily soluble that the deposits could not exist even in a moderately rainy region, but there is little trouble on that score in northern Chile. The high Andes on one side and the cold Humboldt or Peruvian current on the other make Chile north of the 30th parallel one of the driest regions in the world. Some places have passed more than a decade without a drop of rain. Other places have a few minutes of scattering sprinkles almost every year. This is said to have been the case in parts of Antofagasta for many years prior to 1910, when there was a heavy shower, followed in 1911 by two days of steady downpour. These occurrences, with rain again in 191?. and, more wonderful still, snow where people living in the region for a generation never had seen snow, have led many residents to believe that "the climate is changing since Halley's comet went past." That water has flowed here at times in the past is shown by the dry gullies and channels. Numerous snow-fed rivers descend the western slopes of the Andes, but their waters soon are evaporated or lost in the dry sands of the pampa. For hundreds of miles along this coast not a perennial stream enters the ocean. If absolute desert exists in the world, it lies in the nitrate pampa.

In crossing this region one can not help feeling the utter helplessness of man in the face of such great expanses of waterless and lifeless wastes. All directions lead to sand, more sand, even to the border of the ocean itself. One fails at first to understand how men are willing to live there year after year: why those who 2:0 away generally come back again