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 a private estate of over two million acres, on which dwell some two thousand people.

well up on the horizon are the high Mesas del Zorillo. Their broad level tops lie in the same plane, at their borders a sheer descent is visible to the point where the talus slope begins and slants off in graceful lines to the rolling lands below. But such configurations are rare in that region. Here and there what is left of that stratum which forms the high floor of these Mesas may be visible, but only as vestiges, for they have mostly disappeared.

Standing at the edge of one of these wide plains and looking across, one may survey at a glance twenty to forty miles of mountain barrier along the opposite side, thirty to fifty miles away. Deep scalloped with cañons and ravines which divide and subdivide into successively smaller branches as we follow their course upwards, they are ultimately lost in the rounded brow of the mountain. Below the steeper slopes the low-lying, far-outreaching butresses of the range finally sink into the plain. At the mouths of the cañons, broad fans of silt, gravel and other detritus from the heights above, spread out and meet their neighbors on the right and left until a long, slightly undulating footslope is formed, and gradually merge into the floor of the valley. Thus the wide valley is gradually being made wider by the building up of its floor, which is the accumulation of ages of the wash from the mountains; the nature of the process is obvious. Where a deep arroyo cuts down through the land a section of the deposit shows