sixteen miles south of Nacori, was a bed of clay thirty feet thick and
about a mile and a half long. On the edge of this field he discovered
a tusk six feet eight inches long and twenty-six inches at its widest
circumference, and having almost the curve of a circle. It was not
petrified and had no bone core, but the hole filled in with clay,
and its colour was a rich mahogany. It was undoubtedly the tusk of
a mammoth.

From the beginning it had surprised me how very ignorant the people
of Sonora were regarding the Sierra Madre. The most prominent man
in Opoto, a town hardly forty miles from the sierra, told me that
he did not know how far it was to the sierra, nor was he able to say
exactly where it was. Not even at Nacori, so close to this tremendous
mountain range, was there much information to be gotten about it. What
the Mexicans know about that region may be briefly summed up thus:
That it is a vast wilderness of mountains most difficult of approach;
that it would take eight days to climb some of the high ridges;
that it contains immense pine forests alive with deer, bear, and
wonderfully large woodpeckers, able to cut down whole trees; and that
in its midst there are still existing numerous remains of a people
who vanished long ago, but who once tilled the soil, lived in towns
and built monuments, and even bridges over some of its cañons.

This general ignorance is mainly due to the fact that until very
recently this entire part of the sierra, from the border of the
United States south about 250 miles, was under the undisputed control
of the wild Apache Indians. From their mountain strongholds these
marauders made raiding expeditions into the adjacent states, west
and east, sweeping down upon the farms, plundering the villages,
driving off horses and herds of cattle, killing men and carrying off