hat had created this rent in the earth.

There was a stretch of miles where steep steps in hard red rock
alternated with long levels of round boulders. Here one by one the
mustangs went lame. And the fugitives, dismounting to spare the faithful
beasts, slipped and stumbled over these loose and treacherous stones.
Fay was the only one who did not show distress. She was glad to be on
foot again and the rolling boulders were as stable as solid rock for
her.

The hours passed; the toil increased; the progress diminished; one
of the mustangs failed entirely and was left; and all the while the
dimensions of Nonnezoshe Boco magnified and its character changed. It
became a thousand-foot walled canyon, leaning, broken, threatening, with
great yellow slides blocking passage, with huge sections split off from
the main wall, with immense dark and gloomy caverns. Strangely, it had
no intersecting canyon. It jealously guarded its secret. Its unusual
formations of cavern and pillar and half-arch led the mind to expect any
monstrous stone-shape left by an avalanche or cataclysm.

Down and down the fugitives toiled. And now the stream-bed was bare of
boulders, and the banks of earth. The floods that had rolled down that
canyon had here borne away every loose thing. All the floor was bare red
and white stone, polished, glistening, slippery, affording treacherous
foothold. And the time came when Nas Ta Bega abandoned the stream-bed to
take to the rock-strewn and cactus-covered ledges above.

Jane gave out and had to be assisted upon the weary mustang. Fay was
persuaded to mount Nack-yal again. Lassiter plodded along. The Indian
bent tired steps far in front. And Shefford traveled on after him,
footsore and hot.

The canyon widened ahead into a great, ragged, iron-hued amphitheater,
and from there apparently turned abruptly at right angles. Sunset rimmed
the walls. Shefford wondered dully when the India would halt to camp.
And he dragged himself onward with eyes down on the rough ground.

When he raised them again the Indian stood on a point of slope with
folded arms, gazing down where the canyon veered. Something in Nas Ta
Bega's pose quickened Shefford's pulse and then his steps. He reached
the Indian and the point where he, too, could see beyond that vast
jutting wall that had obstructed his view.

A mile beyond all was bright with the colors of sunset, and spanning
the canyon in the graceful shape arid beautiful hues of a rainbo