282

VEINS OF TASCO.

grande, and sunk the pit of La Esperanza; when
a second time he acquired immense wealth. The
silver produce of the mine of Zacatecas rose then
to nearly 330,000 lbs. troy per annum; and though
the abundance of metals did not long continue the
same, he left at his death a fortune of nearly
He compelled his daughter
125,0007. sterling.
In
to enter into a convent, that he might leave his
whole fortune to an only son, who afterwards vo-
luntarily embraced the ecclesiastical office.
Mexico, and every where else in the Spanish pro-
vinces, it is extremely rare to see children follow-
ing the profession of their fathers; and we do not
find there, as in Sweden, Germany, and Scotland,
families in which the business of miner is here-
ditary.

The veins of Tasco and the Real de Tehuilotepec
traverse barren mountains, furrowed by very deep
ravines.

The mining districts of Tasco and of the Real de Tehuilotepec contain a great number of veins, which, with the exception of the Cerro de la Compaña, are all directed from the north-west to the south-east, hor. 7-9. These veins, like those of Catorce, traverse both the limestone and the micaceous slate which serves for its base; and they exhibit the same metals in both rocks. These metals have been much more abundant in the limeThe mines have become extremely poor stone. since it became necessary to work the veins in the

micaceous slate. A very intelligent and very active miner, Don Vicente de Anza, wrought the mines of Tehuilotepec to the depth of 122 fathoms; and he cut two excellent levels for a length of 3,936 feet; but unfortunately he found that the same veins which had furnished considerable riches at the surface of the earth, were at great depths as poor in red silver ores, as they were abundant in galena, pyrites, and yellow blende.

An extraordinary event which happened on the 16th February 1802, completed the ruin of the miners of this district. The mines of Tehuilotepec, like those of Guautla, have at all times wanted the necessary water to put in motion the stamping mills and other machines which prepare the minerals for the process of amalgamation. The most abundant stream used in the works, issued from a cavern in the limestone rock called the Cueva de San Felipe. This rivulet was lost in the night between the 16th and 17th of February; and five days afterwards a new spring was found at five leagues distance from the cavern, near the village of Platanillo. It has been proved by researches of the greatest interest for geology, that there exists in this country, between the villages of Chamacasapa, Platanillo, and Tehuilotepec, in the bosom of calcareous mountains, a series of caverns and natural galleries, and that subterraneous rivers, like those of the county of Derby in England, traverse those galleries, which communicate with one another.

The veins of Tehuilotepec are in general western (spathgänge); they are from six to ten feet in extent, and being separated from the rock by a list of clayey loam, they form several lateral branches, which enrich the principal vein where they fall into it (se trainent). Their structure has this peculiarity, that the metallic mineral is rarely disseminated throughout all the lode, but is collected in a single band, which is sometimes near the roof, and sometimes near the wall of the vein. In general, the mineral depositories of Tasco and Tehuilotepec are extremely variable in their produce. As to the nature of the mass of which they are constituted, I perceived four very different formations of veins: viz.

1. Brown, red, and yellow oxides of iron, in which native and sulphuretted silver are disseminated in impalpable particles; cellular brown ironstone, specular iron, a little galena, and magnetic iron, and blue carbonate of copper. This formation, analogous to that of the pacos of Fuentestiana, and Pasco in Peru, is designated at Tehuilotepec, by the name of tepostel. It is found at small depths from the surface (in ausgehenden) in the mines of San Miguel, San Estevan, and La Compaña, near Tasco, as well as at the Cerro de Garganta, near Mescala. The tepostel is generally not so rich as the Pasco of Peru; but is so much the richer at Tasco, as the oxide of iron is more mixed with azure of copper: it generally, however, does not

contain more than 80 ounces of silver per

ton.

2. Calcareous spar, a little galena, and transparent lamellar gypsum, containing drops of water with air, and filiform native silver.

3. Light-red silver, brittle vitreous silver (sprödglaserz), much yellow blende, galena, very little of iron pyrites, calcareous spar, and milk-quartz. This formation, which is the richest of all, displays the remarkable phenomenon, that the minerals the most abundant in silver, form spheroidal balls, from 3.93 to 4.71 inches in diameter, in which red silver, mixed with brittle vitreous silver, and native silver alternate with bands of quartz. These balls, which have seldom been found but at a depth of from 50 to 200 feet, are nidulated in a course of calcareous and brown spar.

4. Much argentiferous galena, which is richer in silver in proportion as the detached pieces are of smaller grain; much yellow blende; little pyrites, quartz and calcareous spar, in the mines of Socabon del Re and de la Marquesa.

All these veins run through a table-land of from 5,550 to 5,910 feet elevation above the level of the sea, which enjoys a temperate climate very favourable to the cultivation of the grains of the old continent.

CHAPTER XV.

Intendancy of Guadalaxara-extent-climate-agricultural produce-principal towns-mines.

THIS province, part of the kingdom of Nueva Galicia, has almost twice the extent of Portugal, with a population five times smaller. It is bounded on the north by the intendancies of Sonora and Durango, on the east by those of Zacatecas and Guanaxuato, on the south by the province of Valladolid, and on the west, for a length of coast of 370 miles, by the Pacific Ocean. Its greatest breadth is 300 miles, from the port of San Blas to the town of Lagos; and its greatest length is from south to