394 MINES OF MEXICO, 
of the veins is for the most part totally independent 
of the nature of the beds which they intersect. 
Great advantage is derived in working the Mexi- 
ean mines, from the circumstance that the most 
important of them are situated in temperate regions 
where the climate is favourable to agriculture. 
Guanaxuatois placed in a ravine, the bottom of which 
is somewhat lower than the level of the lakes of the 
valley of Mexico. Zacatecas and the Real de Catorce 
are a little higher; but the mildness of the air at 
these towns, which are surrounded by the richest 
mines in the world, is a contrast to the cold and dis- 
agreeable atmosphere of the Peruvian districts. 
The produce of the Mexican mines is very un- 
equally apportioned. The 2,500,000 marks, or 
1,541,015 troy pounds of silver annually exported 
to Europe and Asia from Vera Cruz and Acapulco, 
are drawn from a very smal] number. Guanaxuato, 
Zacatecas, and Catorce, supply more than the half; 
and the vein of Guanaxuato alone yields more than 
a fourth part of the whole silver of Mexico, and a 
sixth of the produce of all America. The following 
is the order in which the richest mines of New Spain 
are placed, with reference to the quantity obtained 
from them :— 
Guanaxuato, in the intendancy of the same name. 
Catorce, in the intendancy of San Luis Potosi. 
Zacatecas, in the intendancy of the same name. 
Real del Monte, in the intendancy of Mexico. 
Bolanos, in the intendancy of Guadalaxara. 
Guarisamey, in the intendancy of Durango. 
Sombrerete, in the intendancy of Zacatecas. 
Tasco, in the intendancy of Mexico. 
Batopilas, in the intendancy of Durango. 
Zuriapan, in the intendancy of Mexico. 
Fresnillo, in the intendancy of Zacatecas. 
Ramos, in the intendancy of San Luis Potosi. 
Parral, in the intendancy of Durango. 
