The last two words, directed to Calder came, with a metallic hardness, for the marshal started as a great black dog slipped from behind a tree and slunk towards him. This was the shadow which moved more swiftly and noiselessly than a human being. "Keep back that damned wolf," he said desperately. "He ain't goin' to hurt you," said the calm voice. "Jest toss your gun to the ground." There was nothing else for it. Calder dropped his weapon with the butt towards Whistling Dan. "Bring it here, Bart," said the latter. The big animal lowered his head, still keeping his green eyes upon Calder, took up the revolver in his white fangs, and glided back to his master. "Jest turn your back to me, an' keep your hands clear of your body," said Dan. Calder obeyed, sweating with shame. He felt a hand pat his pockets lightly in search for a hidden weapon, and then, with his head slightly turned, he sensed the fact that Dan was dropping his revolver into its holster. He whirled and drove his clenched fist straight at Dan's face. What happened then he would never forget to the end of his life. Calder's weapon still hung in Dan's right hand, but the latter made no effort to use it. He dropped the gun, and as Calder's right arm shot out, it was caught at the wrist, and jerked down with a force that jarred his whole body. "Down, Bart!" shouted Dan. The great wolf checked in the midst of his leap and dropped, whining with eagerness, at Calder's feet. At the same time the marshal's left hand was seized and whipped across his body. He wrenched away with all his force. He might as well have struggled with steel manacles. He was helpless, staring into eyes which now glinted with a yellow light that sent a cold wave tingling through his blood. The yellow gleam died; his hands were loosed; but he made no move to spring at Dan's throat. Chill horror had taken the place of his shame, and the wolf-dog still whined at his feet with lips grinned back from the long white teeth. "Who in the name of God are you?" he gasped, and even as he spoke the truth came to him--the whistling--the panther-like speed of hand--"Whistling Dan Barry." The other frowned. "If you didn't know my name why were you trailin' me?" "I wasn't after you," said Calder. "You was crawlin' along like that jest for fun? Friend, I figger to know you. You been sent out by the tall man to lay for me." "What tall man?" asked Calder, his wits groping. "The one that swung the chair in Morgan's place," said Dan. "Now you're goin' to take me to your camp. I got something to say to him." "By the Lord!" cried the marshal, "you're trailing Silent." Dan watched him narrowly. It was hard to accuse those keen black eyes of deceit. "I'm trailin' the man who sent you out after me," he asserted with a little less assurance. Calder tore open the front of his shirt and pushed back one side of it. Pinned there next to his skin was his marshal's badge. He said: "My name's Tex Calder."