If the few officers in command had ever attempted to teach them military discipline, the result was not apparent in the line they formed; but any man who looked at their swarthy faces, the hawklike profiles, and deep-set, steady eyes, would know that they were fighters. After all, a straight line on parade has very little to do with actual warfare, and these men had proved their worth under fire. To be sure, it was the fire of Mexican guns, and perhaps that was why the officers were so quiet and unassertive; for every one of these big, upstanding Indians had been captured in the Yaqui wars and deported to the henequen fields of Yucatan to die in the miasma and heat. But they had come from a hardy breed and the whirligig of fortune was flying fast--Madero defeated Porfirio Diaz; fresh revolutions broke out against the victor, and, looking about in desperation for soldiers to fill his ranks, Madero fell upon the Yaquis. Trained warriors for generations, of a race so fierce that the ancient Aztecs had been turned aside by them in their empire-founding migration, they were the very men to whip back the rebels, if he could but win them to his side. So Madero had approached Chief Bule, whom Diaz had taken under a flag of truce, and soon the agreement was made. In return for faithful service, Mexico would give back to the Indians the one thing they had been fighting a hundred and sixty years to attain, their land along the Rio Yaqui; and there they should be permitted to live in peace as their ancestors had done before them. And so, with a thousand or more of his men, the crafty old war-chief had taken service in the Federal army, though his mind, poisoned perhaps by the treachery he had suffered, was not entirely free from guile. "It is the desire of the Yaquis," he had said, when rebuked for serving under the hated flag of Mexico, "to kill Mexicans, And," he added grimly, "the Federals at this time seem best able to give us guns for that purpose." But it had been a year now since Bule had passed his word and, though they had battled valiantly, their land had not been given back to them. The wild Yaquis, the irreconcilables who never came down from the hills, had gone on the war-path again, but Bule and his men still served. Only in two things did they disobey their officers--they would not stack their arms, and they would not retreat while there were still more Mexicans to be killed. Otherwise they were very good soldiers. But now, after the long campaign in Chihuahua and a winter of idleness at Agua Negra, they were marching south toward their native land and, in spite of the stern glances of their leaders, they burst forth in weird Yaqui songs which, if their words had been known, might easily have caused their Mexican officers some slight uneasiness. It was, in fact, only a question of days, months, or years until the entire Yaqui contingent would desert, taking their arms and ammunition with them.