employing many men who live in the villages belonging to the works--and stores, schools, and other useful institutions exist to make life upon these bare plains endurable. The “caliche” is worked locally in these factories, where it is first crushed, then dissolved in boiling water, the insoluble matter precipitated, the solution containing the nitre being allowed to crystallise, and the product after being roughly dried is exported in bags. Curious remains of birds and animals and human beings are frequently discovered in the “caliche” deposits, all well preserved, and many of these specimens of the earlier fauna of the country are found in the museum at Lima and elsewhere. The deposits of “caliche” are of course limited, and there is great difference of opinion as to when the beds will be exhausted. But some time ago the Collector of Customs at Valparaiso estimated that thirty-five million metric tons remain at present in private properties--and about thirty million metric tons in the Government properties--and, in his opinion, by 1923 the remaining deposits upon private properties will have been exhausted, whilst the Government properties may last fifteen years longer. Although the Government receive a large revenue from the sale of their stock of this valuable deposit, by the time it is exhausted other sources of wealth will have been developed, for the agricultural possibilities are practically unlimited. Chili also possesses the largest guano deposits in the world, and here is another source of wealth. The material, which consists of the droppings of pelicans, is the most valuable manure known. It is found along the hills that lie near the seashore, and helps to give those weird effects of dirty snow lying on brown earth. Precisely when its use was first discovered is not known, but there is evidence to show that its value was understood by the subjects of the Incas, and it helped to give them that expertness in agriculture which so astonished the Spaniards in the sixteenth century. Humboldt introduced it into Europe early in the nineteenth century, and since then its employment has increased among farmers everywhere, and has been greatly fostered by the improvements which chemists and inventors have brought about in the methods of preparing it for use. Unlike nitrates, there is little possibility of the supplies of this fertiliser ever becoming exhausted. CHAPTER XV _Argentina_