d try to urge her mule into a trot--a futile effort, since
the beast had a much higher regard for his skin than she had for hers;
and the mule of the arriero was but a few feet ahead.

Thus we continued day after day, I can't say how many. There was a
fascination about the thing that was irresistible. However high the
peak we had ascended, another could be seen still higher, and that,
too, must be scaled.

The infinite variety of the trail, its surprises, its new dangers, its
apparent vanishings into thin air, only to be found, after an all but
impossible curve, up the side of another cliff, coaxed us on and on;
and when or where we would have been able to say, "thus far and no
farther" is an undecided problem to this day.

About three o'clock one afternoon we camped in a small clearing at the
end of a narrow valley. Our arriero, halting us at that early hour,
had explained that there was no other camping ground within six hours'
march, and no hacienda or pueblo within fifty miles. We received his
explanation with the indifference of those to whom one day is like
every other day, and amused ourselves by inspecting our surroundings
while he prepared the evening meal and arranged the camp beds.

Back of us lay the trail by which we had approached--a narrow, sinuous
ribbon clinging to the side of the huge cliffs like a snake fastened to
a rock. On the left side, immediately above us, was a precipice some
thousand feet in height; on the right a series of massive boulders, of
quartzite and granite, misshapen and lowering.

There were three, I remember, placed side by side like three giant
brothers; then two or three smaller ones in a row, and beyond these
many others ranged in a mass unevenly, sometimes so close together that
they appeared to be jostling one another out of the way.

For several days we had been in the region of perpetual snow; and soon
we gathered about the fire which the arriero had kindled for our camp.
Its warmth was grateful, despite our native woolen garments and heavy
ponchos.

The wind whistled ominously; a weird, senseless sound that smote the
ear with madness. The white of the snow and the dull gray of the rocks
were totally unrelieved by any touch of green or play of water; a spot
lonely as the human soul and terrifying as death.

Harry had gone to examine the hoofs of his mule, which had limped
slightly during the afternoon; Le Mire and I sat side by side near the
fire, gazing at th