acks with a cleverness that is almost human: yet, whenever a
mule runs accidentally against some projection, or its foot slips,
the poor beast invariably loses its balance, and over it goes,
down the hill with ever-increasing velocity.

On one occasion I heard a noise coming from above without being at
first able to discern what caused it. A few stones came tumbling down,
and were presently followed by a donkey, pack and all, turning over
and over with astounding speed. It cleared a perpendicular rock some
twenty feet high and landed at its base, rolling over twice. Then,
to my amazement, it rose to its feet in the midst of its scattered
cargo. And do you know what that cargo consisted of?--a case of
dynamite and our tool chest! As fast as their legs could carry them,
two Mexicans were by its side, promptly reloading the donkey and
leading it up to the trail as coolly as if nothing had happened. A
very fine mule, raised on the plains of Arizona, was naturally giddy,
and met with such a mishap three times in one day, tumbling down 150
to 200 feet without, however, being seriously hurt. At first I was
greatly shocked to see the animals thus rolling over and over with
their packs, down the mountain sides, never stopping until checked by
some large tree or rock, sometimes 200 feet below. But the Mexicans
were evidently quite accustomed to such happenings, which seemed to
be in the regular line of their travel.

I could not help admiring the agility as well as the valour of my
Mexican packers and muleteers on such occasions. They moved about as
sure-footed and quick as sailors on their ship, and always on the
alert. Whenever one of the poor beasts lost its foothold, the men
would instantly run after it, and as soon as some obstacle stopped
its downward career they would be by its side and relieve it of its
burden. Of course, sometimes the animal was badly bruised about the
head, and unable to carry a pack for a few days; but, _mira-bile
dictu!_ in the majority of cases it rose to its feet. Then, after
giving it a few moments' respite, the packers would strap the cargo
again on its back, unless they deemed it proper to take a part of
it upon themselves, so that the beast might more safely climb the
declivity. The men really seemed indefatigable. One of them once took
upon his head a large case of honey and carried it up the ridge on a
run. Strange as it may sound, on my first journey across the Sierra
Madre I did not lose