The mesa trail was wide—­in reality a cross-country road, so Bartley had opportunity to try Dobe’s different gaits.  The running walk was a joy to experience, the trot was easy, and the lope as regular and smooth as the swing of a pendulum.  Finally Bartley settled to the best long-distance gait of all, the running walk, and began to enjoy the vista; the wide-sweeping, southern reaches dotted with buttes, the line of the far hills crowded against the sky, and the intense light in which there was no faintest trace of blur or moisture.  Everything within normal range of vision stood out clean-edged and definite.

Unaccustomed to riding a horse that neck-reined at the merest touch, and one that stopped at the slightest tightening of the rein, Bartley had to learn through experience that a spade bit requires delicate handling.  He was jogging along easily when he turned to glance back at the town—­now a far, huddled group of tiny buildings.  Inadvertently he tightened rein.  Dobe stopped short.  Bartley promptly went over the fork and slid to the ground.

Dobe gazed down at his rider curiously, ears cocked forward, as though trying to understand just what his rider meant to do next.  Bartley expected to see the horse whirl and leave for home.  But Dobe stood patiently until his rider had mounted.  Bartley glanced round covertly, wondering if any one had witnessed his impromptu descent.  Then he laughed, realizing that it was a long way to Central Park, flat saddles and snaffles.

A little later he ate two of the sandwiches Wishful had thoughtfully provided, and drank from the canteen.  Gradually the shadows of the buttes lengthened.  The afternoon heat ebbed away in little, infrequent puffs of wind.  The western reaches of the great mesa seemed to expand, while the southern horizon drew nearer.

Presently Bartley noticed pony tracks on the road, and either side of the tracks the mark of wheels.  Here the wagon had swung aside to avoid a bit of bad going, yet the tracks of two horses still kept the middle of the road.  “Senator Brown—­and Cheyenne,” thought Bartley, studying the tracks.  He became interested in them.  Here, again, Cheyenne had dismounted, possibly to tighten a cinch.  There was the stub of a cigarette.  Farther along the tracks were lost in the rocky ground of the petrified forest.  He had made twenty miles without realizing it.

Winding in and out among the shattered and fallen trunks of those prehistoric trees, Bartley forgot where he was until he passed the bluish-gray sweep of burned earth edging the forest.  Presently a few dwarf junipers appeared.  He was getting higher, although the mesa seemed level.  Again he discovered the tracks of the horses in the powdered red clay of the road.

He crossed a shallow arroyo, sandy and wide.  Later he came suddenly upon a red clay cutbank, and a hint of water where the bank shadowed the mud-smeared rocks.  He rode slowly, preoccupied in studying the country.  The sun showed close to the rim of the world when he finally realized that, if he meant to get anywhere, he had better be about it.  Dobe promptly caught the change of his rider’s mental attitude and stepped out briskly.  Bartley patted the horse’s neck.