The Sierra Madre was now so close that the tilted masses of its rocks
seemed to overhang our tents threateningly where we had pitched them
at its foot. From this camp we had about the same splendid view as
from the ridge of Huehuerachi we had just left behind; and between
us and the foot-hills of the Sierra de Bacadehuachi stretched out a
vast mass of barren-looking rocks and hills. The Mexicans call them
_agua blanca_, a designation also applied to the small water course
that runs through them in a northerly and southerly direction, but
which from our point of view could not be made out in the chaotic
confusion. Away off toward the north, at a distance of from fifteen
to twenty miles, could be seen a high chain of sharp peaks.

I may mention here that I found the water of many streamlets and
brooks throughout the western mountains of Mexico to have a slightly
whitish colour and a dull, opalescent look, like a strong solution
of quinine. The Mexicans call it _agua blanca_, or _agua zarca_, and
consider it the best water they have. Many places, especially ranches,
are named after it. In the locality where we now found ourselves the
water had a slightly bitter taste, owing to a strong admixture of
iron and other minerals, but generally it was very palatable.

Here, only twenty-three miles from Nacori, and at an elevation
of 4,000 feet, we were obliged to make camp for three days. Dense
fogs and occasional hard showers made travel impossible. Besides,
our principal guide, Agustin Rios, became dangerously ill. He was
sixty-five years old, and I decided to send him back.

When I hired him I had not been aware that he was afflicted with an
incurable disease, and that on this account his wife had tried to