Page:Mexico, California and Arizona - 1900.djvu/253

 Rh substituted large zinc cones for the ordinary sails and slats. The extracting processes were more entertainingly seen, however, at the beneficiating haciendas themselves. The "Loreto" is one of the principal. The ore is crushed her by the Cornish stamp, which drops a succession of iron-shod beams upon it; the Chilean mill, which grinds it by means of superposed revolving stones; or the arrastra. The last is the most primitive, cheapest, and still most in use. The crushing is done by common stones, hung to the arms of a horizontal cross, dragged round and round in a circular bed by mule-power.

Then follows the making of tortas, "the patio system," which had its origin here in 1557. Numerous large mud-pies of the powdered ore and water are laid out on a vast open court floored with wood. The chemicals mentioned are thrown in in successive stages, and troops of broken-down horses are driven around in the mass for from two to three weeks in succession, thoroughly mingling it together. It is then brought in wheel-barrow loads to washing-tanks, where men and boys puddle it bare-legged till the metal falls to the bottom and the detritus runs away. "Rebellious" ores are treated by first calcining, then separating with mercury by "the barrel process." This last is done chiefly at the hacienda of Velasco, on the way to Regla.

Of the two hundred and sixty-seven mines in the district, seven are worked by the Real del Monte Company. The paying mines are comparatively new, discovered within the last twenty or thirty years. The old Spanish mines do not pay, and are, in fact, little worked. The stories of old Spanish mines, abandoned, perforce, at the date of the Independence, and ready to yield splendid returns to whoever will reopen them, serves very well as `