He could see their brandished spears glancing in the sun glare.

They would soon be within reach, thrusting through his body; their barbed blades piercing him between the ribs.
No time for sentiment nor dallying now, without the certainty of being slain.
He gave one last look at his steed, and then letting go the rein, turned away, as one who, by stern necessity, abandons a friend, fearing reproach for what he does, but without the power to explain it.
For a time the abandoned steed kept its place, with glances inquiringly sent after the master who had forsaken it.

Then, as the yelling crew came closer behind, it threw up its head, snorted, and tore off with trailing bridle.
Hamersley had turned to the guide, now also afoot, but still retaining hold of his horse, which he was conducting towards the crack in the cliff, with all his energies forcing it to follow him; for the animal moved reluctantly, as though suspecting danger inside the darksome cleft.
Still urging it on, he shouted back to the Kentuckian, "You go first, Frank! Up into the kanyon, without losin' a second's time.

Hyar, take my gun, an' load both, whiles I see to the closin' o' the gap." Seizing both guns in his grasp, Hamersley sprang into the chine, stopping when he got well within its grim jaws.
Wilder went after, leading his steed, that still strained back upon the bridle.
There was a large stone across the aperture, over which the horse had to straddle.

This being above two feet in height, when the animal had got its forelegs over Wilder checked it to a stand.