272 
CAVE AND CLIFF DWELLERS. 
antee ourselves one thousand five hundred 
to two thousand feet of plain sailing. 
On the trail from Batopilas to Parral is 
the “La Infinitad” of the Mexican 
miners (the Infinity), where the trail, not 
over half a foot wide, looks down a sheer 
vertical twenty-six hundred feet. 
Presently the pines begin to grow less 
numerous and to be interspersed with the 
many varieties of oak for which the 
Sierra Madres will one day be noted, the 
most conspicuous of which is the encino 
robles , or everlasting oak, a beautiful tree 
with enormous leaves of a bright green 
color. The oaks increase in numbers as 
we descend, and the pines soon disappear ; 
for we are getting out of the country of 
cold nights, which the conifers love so 
much. Presently a thorny mesquite is 
seen, and in half an hour we have traveled 
