This quantity, large as it is, sinks into comparative insignificance when compared with the enormous masses of silver with which, ever since their discovery and conquest by Cortez and Pizarro, Mexico and Peru have enriched the world.
The Mexican silver mines, which deserve a particular notice from the immensity of their produce and the interesting details with which their history abounds, are mostly situated on the back or on the western slopes of the Cordillera of Anahuac at elevations which sometimes approach the line of perpetual snow. But little is known of their first history. The lodes of Tasco and Pachuca appear to have been worked soon after the conquest, and in 1548, twenty-eight years after the death of Montezuma, the mines of Zacatecas were opened, though situated above 400 miles from the capital. Muleteers travelling from Mexico to Zacatecas are said to have discovered the silver mines of Guanaxuato.
Many of my readers will no doubt be surprised to hear that the Mexican silver ores are generally poor. On an average they contain only from three to four ounces of silver per cwt., much less than the ores of Annaberg, Marienberg, and other districts of Saxony. Their comparative poverty is, however, amply redeemed by their abundance and the facility with which they are worked.
After these preliminary remarks I will now briefly describe the chief Mexican silver mines. The Sierra de Santa Rosa, a group of porphyritic hills, rises in the centre of the province of Guanaxuato. Partly arid and partly covered with the evergreen oak, it attains an absolute height of from 8,000 to 9,000 feet; but, as the neighbouring plain is nearly 6,000 feet above the sea, it hardly attracts the notice of the traveller accustomed to the vast proportions of the Andes.
The southern slope of this porphyritic range is crossed by the famous Veta Madre of Guanaxuato, the richest silver lode as yet discovered in Mexico. This enormous vein, which traverses the country for upwards of eight miles, with an average width of from 120 to 135 feet, is, however, not productive throughout its whole extent, but the ore occurs in branches and bunches, leaving intermediate spaces of dead and unproductive ground. Among the numerous mines that have been opened along its course, the Valenciana exhibited, at the beginning of the present century, the almost unparalleled example of a mine which, during a period of more than forty years, never yielded its proprietors less than an annual income of from 80,000l. to 120,000l. The part of the Veta in which it is situated had remained unexplored till 1760, when Obregon, a young Spaniard, began to work it, with the assistance of some friends who advanced him the necessary capital. In the year 1766 the diggings had reached a depth of 240 feet, and the expenses were far greater than the proceeds. But Obregon clung with the passionate ardour of a gambler to the hazardous enterprise on which he had staked all his hopes of fortune. In 1767 he entered into partnership with a small shopkeeper, Otero, who was destined soon to share the fabulous riches that were about to reward his perseverance. Already in the following year the produce of the mine considerably increased, and in 1771 it began to yield enormous masses of sulphuret of silver. From that time till 1804, when Humboldt left Mexico, it never produced less than 560,000l. worth of silver annually, and the net profits of the partners amounted in some years to 240,000l.
Under the title of Conde de la Valenciana, Obregon maintained the simple habits and the urbanity of character which had distinguished him in poverty. When he began to work his mine, the goats were feeding on the spot where ten years later a thriving town of 8,000 souls had started into existence. Guanaxuato, the capital of the State of the same name, is indebted to the neighbourhood of the richest silver mines in the world for its origin and prosperity. Inclosed in a narrow valley, its houses rise in terraces one above the other; and the contrast of the magnificent abodes of the rich mining proprietors with the miserable huts of their dependants adds to the singular appearance of the place. The Mexican miner is, however, not so poor as his wretched dwelling might lead us to suppose. In some measure he shares the fortunes of the proprietors of the mines, as he is entitled to part of the ore; so that when the vein is more than usually productive his weekly profits may amount to as much as a hundred dollars. Yet he never thinks of purchasing a piece of land, or of repairing his hut, when favoured by fortune; but foolishly squanders his money in drinking and gambling, and seldom returns to his work before his last farthing has been spent.
The population of Guanaxuato naturally fluctuates with the prosperity of the mines. In 1806 and 1807, when they were in the highest state of activity, it amounted to 90,000 souls; during the wars of independence it sank to 20,000, but since then it has again risen to 60,000.
Next to the mines of Guanaxuato those of Zacatecas are distinguished by their richness. They are likewise situated on the great central plateau of the Cordillera in a wild mountain region whose forbidding aspect forms a strange contrast to the riches concealed under its surface. In 1826 the United Mexican and the Bolaños Company undertook the working of these mines; and two years after, the latter had the good fortune to find an exceedingly rich vein, which up to the year 1834 produced no less than 1,680,316 marks of silver.
Before 1770 the populous district of Alamos de Catorce in the State of San Luis de Potosi, was still a complete desert. About this time a free negro, named Milagros, who made a scant livelihood as an itinerant musician, having lost his way, was obliged to pass the night in the forest. On the following morning he found a few drops of silver on the spot where he had made a fire, and, on a closer examination, discovered the rich cropping out of a bed of argentiferous ores. He lost no time in establishing the right of property which he derived from his discovery, and opened the shaft Milagros, which, in a few years, made him a wealthy man.
Soon after Don Barnabé de Zepeda discovered the chief vein of Catorce—the Veta Madre—which continued to be worked with great success until the revolution. This event having proved as destructive to the draining machines of Catorce as to those of Guanaxuato and Zacatecas, a contract was made with an English house for the furnishing of a steam-engine, the first ever seen in Mexico. It was landed at Tampico in May 1822, but arrived at Alamos six months later, as the carts which dragged the heavy piece of machinery broke down every moment on the wretched roads which lead to the central plateau on which the mines are situated. This, however, was but the prelude of new difficulties; for as the neighbouring forests could not furnish wood fit for the purpose, it was necessary to order iron pump-tubes in England, which did not arrive before 1826, so that the engine could not be set to work until four years had passed after its arrival in Mexico. The history of Catorce affords many remarkable examples of good fortune; but as most of the rich mineros (mine-proprietors) were men of low birth and without education, they squandered their treasures as fast as they acquired them. Medellin, the proprietor of the mine Dolores, once spent 36,000 dollars on a christening party; and at times, when the share of the hewers amounted to one-third of the extracted ores, a common miner would stake two or three thousand dollars on the issue of a cock-fight.