the whole floor, by which means a small Torta may be amalgamated perfectly in four or five days, instead of employing as many weeks to effect it, as is the case at present.
It being absolutely impossible to avoid the use of Mexican mining terms, in an account of the mines of that country, it may be advisable to give here a concise explanation of their signification. The Torta contains fifteen Montones of ore, which has already undergone the process of dressing and stamping; and each Monton contains ten Cargas (or loads) of twelve Arrobas (25lbs.) or three quintals each.
To extract the silver contained in this mass, seven hundred pounds of quicksilver are required, of which from seventy-five to one hundred pounds are lost. To this are added eleven Cargas of Rock Salt, or four and a-half of Sea Salt, and from three to three and a-half Cargas of Magistral, (red copper ore roasted,) which is worth at Chico from eleven to sixteen dollars the Carga, being brought from Zacualpan, Angangeo, or San José del Oro, a distance of full thirty leagues.
All these ingredients are entirely lost in the process: the expense of which varies, in the different Mining districts, in proportion to the greater or less facility with which they are obtained.
The German Directors at Chico, Messrs. Du Berg and Kloppenberg, informed me that they found that no general rule or theory would apply to amal-
