“Saltpeter, or nitrate of soda, is found mixed with other substances. The beds contain four layers of material, the next lowest being that of the nitrate itself. Above this are the _chuca_, on the surface, which is nothing more than the accumulation of ages; the _costra_ beneath, a harder and older mass, but still a somewhat worthless débris; the _caliche_, the real nitrate of soda, and, finally, the stratum of bed rock called _gova_. To obtain the nitrate, a shaft is sunk to the _gova_, on which powder is placed and exploded; the overlying mass is thrown up and the _caliche_ containing the nitrate scattered over the ground. This is then collected and taken to the refining works for preparation into refined or almost pure nitrate of soda, ready for export. In the _oficinas_” (refining works) “machinery of the most economical and effective pattern is used, and the methods of refining the salt are according to the best researches of industrial chemistry. The same is true of the facilities for transportation to the steamer. Many small but well-equipped railways are in operation in the fields, and they carry the product to the coast towns, from which they are finally shipped abroad.... Great Britain takes about forty per cent., Germany and the United States each about twenty per cent., France about ten per cent., and the remainder goes to such far-away places as Egypt, Japan, the Hawaiian Islands, and Australia. _In fact, without nitrate the great agricultural producers cannot advance._” And it is well for Chile that these nitrate deposits have proven of such great value—they were acquired only at the cost of a long and expensive war. Formerly the Province of Antofagasta belonged to Bolivia and the Provinces of Tarapacá and Tacna to Peru. The dividing line between Chile and Bolivia, it appears, had always been a bone of contention, and, in 1866, while these republics were allied in a war with Spain, a treaty had been entered into between them, fixing a boundary and agreeing that the citizens of either should have the right to engage in mining operations in the territory of the other, and export the products free of all taxation, within a certain limited area. It appears also that in 1870 Bolivia, for a money consideration, granted to a company composed of Chileans and Englishmen the right to work the nitrate beds both in and north of the treaty area, also to construct a mole at the port of Antofagasta and a road to Carácoles, where rich silver mines had been discovered. The mole was constructed and not only a road but a railroad, and the company is said to have invested heavily in various plants for the preparation of the nitrate and the reduction of the silver ore. As a result, as it was contended, it was Chilean and British capital, and principally Chilean energy and labor that developed the wealth of the region.