Niltci, the Navaho boy, sprang to his feet grunting assent eagerly. His lithe form bounded down the slope towards a grass meadow, his red bandanna a blazing note of color, set off by an equally blazing white cotton shirt contrasting with his long, dark blue leggins which sparkled with rows of barbaric silver buttons. In a trice he was leading back Scotty’s chestnut mare and his own flea-bitten desert pony. Ever since Niltci had miraculously “disappeared” during the religious excitements of his own people over the Black Panther, he had been with Scotty on his mining expeditions down here, far to the south in the Apache country of White River and far away from his own people. To his white friends he had owed his life that time--a debt that, to a Navaho, is never paid. He handed Scotty the mare’s halter and started deftly saddling his own pony. Ruler’s bays came unceasingly down through the mountains. Their giant coonhound was of an indomitable persistence; he could be depended upon to follow that trail, whatever it was, for days on end without relenting. “Up the coulée, Niltci!” shouted Scotty, vaulting his horse and clattering down the slope from camp. Behind him the fast hoofbeats of the Navaho’s pony followed. The mare crossed the creek bottom in a single jump and began working up the opposite flank in a long slant. On ahead an occasional yelp from Ruler gave inkling of his whereabouts. He was traveling fast, for the distance between them did not seem to close up. Frightened deer burst from cover and dashed down and across the stream bottom as they rode. A wild turkey, scared into flight by the showers of rolling stones struck loose by the horses, soared over the willows in the ravine and disappeared in a mass of thick green. Then, behind Scotty, Niltci grunted eagerly and made a queer sound that was half a yelp. “Yep! I see him, Niltci--cougar! There he goes!--regular old he-one!” gasped Scotty, jouncing in his saddle as he bent to drag his rifle from the holster. The mare shied as the heavy .405 swung out around her flanks. Scotty’s knees gripped her fast and he let the horse go with the bridle reins dropped over the pommel. Ruler’s deep tones now came back in explosive volleys. “_Ow-ow-ow! Ow-ow-ow!_” he sang, belling a hot trail. “Heading north, up the cañon!” yelled Scotty, galloping through the timber at full speed. “_Look_ at him _go_!” He pointed out a running cougar far up on the yellow mountain sides, galloping along in easy bounds that seemed effortless. His tawny body doubled and stretched out in the queer lope of the cat tribe, now trotting with fast-moving feet, now humping up in the swinging bounds of the gallop. He seemed very like a buff and white household cat magnified to enormous size. His tail drooped behind, tapering from a thick root seemingly as wide as his hips to a ropy furry length that undulated as he sprang easily up over the rock ledges.