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Rh million dollars a year. There are seven smelting furnaces, employing from six hundred to one thousand men and turning out one thousand tons of copper a month.

There are glass and brick works established at Lota, also machine shops. The two towns. Upper and Lower Lota, have together a population of 14,000. Other extensive coal mines in Chile are the Schwager at Coronel, Rojas at the same place, the Errázuriz at Lebu, and the Arauco Company's mines.

But the true source of Chile's wealth and excellent credit is to be found in the nitrate works of the north. The vast deserts between Copiapo and the Camerones, once considered only a worthless waste, have been called a great natural chemical laboratory, for here various kinds of salts have been precipitated in immense quantities. Not only is this region rich in salts, but here are also some of the best paying mines on the coast. The value of the fertilizing product from the nitrate of soda deposits, called in the natural state calicheras, is too well known to need mention here. The calicheras are situated in the desert just below the surface, in the old dried up lake beds. It is on the sides, or rings, of these that the richest deposits are found. The deposits are detected by small natural holes, caused probably by the action of water at some period of the formation, and by fissures in the surface. The salitreras are situated at intervals on the east slope of the coast Cordillera along the edge of the pampa which lies between the Cordillera and the Andes, and at an elevation of from three thousand to four thousand feet above the sea level. They vary in richness; the calicheras near Antofagasta contain from fifteen to twenty per cent of nitrates, these of Tarapacá as much as seventy per cent.