Almaden is a town in Spain, about sixty miles north of Cordova. It is noted for its quicksilver mines, which are the oldest and among the largest in the world.
The mines were worked by the Romans.
The principal mine is directly under the town, and is about one-fifth of a mile below the surface.
Convict labor was long employed, but now hired men are used.
The mines are worked day and night in the winter, but are closed during the summer, when the heat makes the fumes rising from the quicksilver too poisonous to breathe.
