He turned and walked toward a door at the further end of the long room, the two men following him between the tables. But Buck had not taken more than half a dozen steps before he stopped abruptly. That curious silence seemed to him too long continued to be natural; there was a hint of tension, of suspense in it. And something about the attitude of the seated Mexicans--a vague sense of watchful, stealthy scrutiny, of tense, quivering muscles--confirmed his sudden suspicion. "Hold up, Bud!" he warned impulsively. "There's something wrong here." As if the words were a signal, the crowd about them surged up suddenly, with the harsh scrape of many chair-legs and an odd, sibilant sound, caused by a multitude of quick-drawn breaths. Like a flash Buck pulled his gun and leveled it on the nearest greaser. "Get out of the way," he ordered, taking a step toward the outer door. The fellow shrank back instinctively, but to Buck's surprise--the average Mexican is not noted for daredevil bravery--several others behind pushed themselves forward. Suddenly Jessup's voice rose in shrill warning. "Look out, Buck! Behind yuh--quick! That guy's got a knife." Stratton whirled swiftly to catch a flashing vision of a tall Mexican creeping toward him, a long, slim knife glittering in his upraised hand. The fellow was so close that another step would bring him within striking distance, and without hesitation Buck's finger pressed the trigger. The hammer fell with an ominous, metallic click. Amazed, Buck hastily pulled the trigger twice again without results. As he realized that in some mysterious manner the weapon had been tampered with, his teeth grated, but with no perceptible pause in the swiftness of his action he drew back his arm and hurled the pistol straight into the greaser's face. His aim was deadly. The heavy Colt struck the fellow square on the mouth, and with a smothered cry he dropped the knife and staggered back, flinging up both hands to his face. But others leaped forward to take his place, a dozen knives flashing in as many hands. The ring closed swiftly, and from behind him Stratton heard Bud cry out with an oath that his gun was useless. There was no time for conscious planning. It was instinct alone--that primitive instinct of every man sore pressed to get his back against something solid--that made Buck lunge forward suddenly, seize a Mexican around the waist, and hurl him bodily at one side of the closing circle.