3 1 4 
CAVE AND CLIFF DWELLERS. 
I shall try and give my readers some 
slight idea of the wealth of this portion 
of a country so famous in early Spanish 
conquest. In those great, broken barran¬ 
cas, leading out to the westward from the 
heart of the Central Sierra Madres, I 
found myself in the richest mineral dis¬ 
trict of America, and probably the richest 
in the world. The fact that this is not 
generally known (and, to tell the truth, 
but very little has ever been published in 
the English language about so rich a dis¬ 
trict, and that little is very old) would 
make it easy to write a book on this 
region alone, and still leave a great deal 
unsaid. One of the late cyclopedias 
says of Mexican mines, “ Almost one-half 
of the total yield [of silver] is derived 
from the three great mining districts 
in Guanajuato, Zacatecas, and Catorce.” 
