Probably Treve had no clear idea why he dashed to the rescue of the man for whom he had no feeling except a vague dislike. While Pancho and Joel had fought upon more even terms, the dog had looked on impersonally, entertained by the spectacle, and with no impulse to interfere. But now that the man was down and helpless, somehow it was different.

To a dog, all men are gods. That does not mean they are his own particular gods or that he has any interest in most of them. But they are of the race which he and his ancestors have served and guarded and worshiped since the days when the new earth was covered with vapor and the Neanderthal man tamed the first wolf-cub.

So now, when Joel Fenno lay stricken and defenseless and the mustang turned on him in murder, the collie played true to ancestral instinct.

Pancho spun about at the dog that had balked his yearning to murder the man. Apparently the collie must be gotten rid of, before the mustang could finish the task of killing Fenno, with any peace and absence of interruption. Wherefore, the pony turned his attention to killing Treve.

But, in less than a handful of seconds, he found he had taken upon himself a job far too big and too dangerous for his powers. The dog entered rapturously into the sport. He was everywhere at once and nowhere at any particular moment.

He was rending the bloody nostrils of the mustang. He was nipping the mustang’s hocks. He was slashing at the throat; he was tearing at face and chest and hips, in almost the same instant. With perfect ease, he eluded the flailing hoofs and the pony’s wide-snapping jaws.

Joel Fenno forgot his own intolerable pain in the fascination of the combat. But, as suddenly as it began, the fight ended. The mustang had wit enough to know when he was bested. Bleeding, smarting, confused, all the lust of battle bitten out of him, he turned tail and fled. After the first few yards of clamorous barking and heel-teasing, Treve let him go and trotted back to the groaning Fenno.

Gravely, inquisitively, the collie stood over the man who had brought him here to shoot him. Down into the tortured face he looked. Joel returned the sorrowful gaze, with something of terror in his own leathern visage. He was jolted out of a lifetime’s beliefs and theories. His thoughts would not assemble themselves.

He tried once more to get to his feet. But his legs were numb. He sought to wriggle along on his stomach toward the mile-off waterhole. There he could quench the awful thirst that had begun to grip him. There, too, he might be found by some passerby, seeking water on the way across the arid waste.

But the pain of even the slightest motion was more than his iron nerve could endure. With a groan he gave up the attempt. Supine and panting, Fenno lay where he had fallen; the great dog standing protectingly above him.