The world was palpably a triangle, baseless to southward; walled out by iron, radiant ramparts--a black range, gateless, on the east; a gray range on the west, broken, spiked, and bristling.

At the northern limit of vision the two ranges closed together to what seemed relatively the sharp apex of the triangle, the mere intersection of two lines.

This point, this seemingly dimensionless dot, was in reality two score weary miles of sandhills, shapeless, vague, and low; waterless, colorless, and forlorn.

Southward the central desert was uninhabitable; opinions differed about the edges.
Still in Arizona, the eye wearied; miles and leagues slid together to indistinguishable inches.

Then came a low line of scattered hills that roughly marked the Mexican border.
The mirage played whimsical pranks with these outpost hills.