as the
lowest point we reached in our crossing of the Sierra Madre between
Chuhuichupa and Temosachic. It took us almost the entire day to move
the animals the one mile and a half to this camp. On the way we had
found some good quartz crystals in the baryte, about four inches high
and one inch in width.

The country before us looked more forbidding than ever, as if it
did not want us to penetrate any further into its mysteries, but our
guide seemed to be quite at home here.

Our march toward Rio Chico was about thirty miles of ups and downs,
ascending to a height of 7,600 feet and descending again some 3,000
feet. In the beginning it was almost impossible to make out the track;
where it did not lead over bare rocks, it was nearly obliterated
by overgrown grass. The first ascent was over a mile long in a
straight line; then, after a little while, came the most arduous
climbing I had until then ever attempted. Following the slope of the
mountain, the track rose higher and higher in long zigzags, without
any chance for the animals to rest, for at least three-quarters of
a mile. It was necessary to push them on, as otherwise the train
would unavoidably have upset, and one or the other have rolled down
the declivity. One large white mule, El Chino, after it had almost
climbed to the top, turned giddy at the "glory-crowned height" it
had reached, and, sinking on its hind legs, fell backward and rolled
heels over head down, with its two large canvas-covered boxes, like
a big wheel. As luck would have it, it bumped against a low-stemmed
old oak that cropped out of the hillside in an obtuse angle to it,
some ninety feet below. Making one more turn up the stem, the mule was
nicely caught between the forked branches, which broke the momentum,
loosened the cargo, and caused the animal to fall back into the high
grass. One box landed close by, the other, containing our library,
pursued its course downward 200 feet further, bursting open on the
way and scattering the wisdom of the ages to the winds, while the
mule escaped without a scratch.

The burros came into camp three hours after us, and the drivers
explained how they had succeeded in bringing them up the long slope
only by constantly punching them to prevent them from "falling asleep."

As we continued our journey toward Rio Chico the panorama of the
sierra changed continuously. We got a side view of the big Mesa de
los Apaches, and many weathered pinnacles of eroded congl