there were traces of small dwellings, huts of undressed stone,
and fragments of pottery. We found three mortars and one pestle,
a remarkable number of metates (the stone on which corn is ground),
and the corresponding grinding stones, showing that a large population
must have once lived here, huddled together in a small space.

But the most striking feature of antiquity met thus far on our journey
were curious stone terraces built across the small gullies. They
are called trincheras (trenches). Some of them do not appear to be
very old, and many present the appearance of tumble-down walls, but
the stones of which they are constructed were plainly used in their
natural state. Although many of the boulders are huge and irregular in
shape, they were used just as they were found. The building material
always conformed to the surroundings: in places where conglomerate
containing water-worn boulders abounded, this was used; where porphyry
was prevalent, blocks of that material were employed. There is no
trace of dressing or cutting, but in the mason work considerable
skill is evident. The walls are not vertical, but incline somewhat
toward the slope on which they are erected. The terrace thus formed
is often filled with soil to the height of the wall-top for a space
of from fifteen to twenty feet. Earth taken from them does not show
any colours. Some of these trincheras measure thirty feet in length
by four feet in height, while the smallest ones I saw were only five
feet long and three feet high. Naturally enough, the largest ones are
in the lower part of the gullies; then, some twenty-five feet back
and above, others almost as large may be found. As the arroyo rises
and narrows, the walls, each placed a little higher up the slope than
the preceding one, are necessarily smaller.

In the mountains near Nacori, especially on their eastern and