large smelting works at Chihuahua which enabled the mines to produce profitably a large tonnage of relatively low-grade ore. In point of tonnage, this camp surpassed Sierra Mojada just before the present revolution, but a portion of the output of the mines was zinc ore which was shipped to Kansas and Oklahoma to be treated by modern methods, aided by cheap fuel.
Parral, State of Chihuahua. This had been one of the old bonanza camps of the Spaniards, who, after extracting the high-grade and easily worked ores, abandoned it as unprofitable. Activities were not resumed until Boston capitalists extended a branch of the Mexican Central Railroad to Parral and Santa Barbara in 1900. Following this there was a period of great activity involving the investment of many millions of American capital in the development of mining properties and the erection of large cyanide and concentrating mills. Perhaps half of these yielded favourable results, although on the whole the camp has never returned more than a small fraction of the money spent by the Americans. The camp was not supplied with cheap hydroelectric power, although a Canadian company had about completed a large plant for this purpose just before operations had to be suspended on account of the last revolution. One of the best-known mines of the camp was the Palmilla, owned by a native Mexican named Pedro
