ish discolorations with a look of professional pride, but you do not exactly fall down in ecstasy over these. There are no forks and spoons hanging ready to your hand, no presentation plate, nor even ingots. The heaps of ore about the shafts do not glitter, and seem good for little but to mend the roads. The principal shafts are about sixteen feet in diameter, the galleries five by eight, and spaced about eighty feet apart. At the San Pedro mine the pumping-engine was of one hundred and fifty horsepower, and another of the same power drew up the malacate, or skip, full of ore in bags of maguey fibre. In some of the old mines, at Guanajuato and San Luis Potosi, they tell us, peons still tote the ore up the interminable ladders on their backs; but this, I think, must be rare. The depth of the Santa Gertrudis is about six hundred feet. The material is marl, limestone, and quartz, all of a soft character and easy to work, but requiring a heavy timbering-up. The clothing of the laborers is ransacked for nuggets by three separate searchers in turn, as they emerge from their work.
There is a Government School of Practical Mining at Pachuca, to which students are sent after finishing the theoretical course at the Mineria, or school of technology, in Mexico. The director, an affable man, showed us the process of beneficiating, or extracting the metal from the rough ore, in miniature. You see the rock first crushed and reduced, with water, to a paste, then mingled with sulphate of copper, common salt, and quicksilver, which get hold of the metal. The quicksilver is afterward withdrawn and reserved for continued use. He gave me, also, a pamphlet of his on a new form of application of "La Accion Mechanica del Viento"- the mechanical action of the wind. A large wind-mill was moving in the court-yard made in accordance with his principle, which `
