Bŏnānză began in 1787, and continued for more than twenty years, in which time the mine was sunk to its present depth, 536 varas. It has now three shafts, one below the other; and this increases the difficulties of the drainage so much, that many are of opinion that it can only be effected by the adit of La Luz, which, as already stated, would enter the lower levels at the depth of 412 varas. The mine, however, is still kept "Amparada" by the present proprietors; that is to say, men enough are employed upon it, from time to time, to preserve a legal right of possession; and in a good week, ores to the amount of four or five hundred dollars are occasionally raised.
The Concepcion belonged originally to Don Bernade Cĕpēdă, who sold the mine in borrasca to the Ăgūirrĕs, with whom Ŏbrĕgōn made a contract similar to that concluded with Davalos for the Purisima. In 1798, a Bonanza commenced, that only terminated with the Revolution.
During the war, the mine was neglected, and became gradually full of water; in consequence of which, a contract was concluded with the house of Gordon and Murphy for a steam-engine, by which it was hoped that the drainage might be speedily effected.
This engine, the first of the kind transmitted to Mexico, was sent out, in 1821, by a special permission from the Spanish Government, and landed at Tampico in May 1822. Its conveyance from this place into the interior was entrusted principally
