As evening came on and the red eye of the sun winked and closed behind a purple range of mountains Denver Russell came out of his cliff-dwelling cave and looked at the old town below. Mysterious shadows were gathering among the ruins, the white walls stood out ghostly and still, and as a breeze stirred the clacking leaves of the sycamores a voice mounted up like a bird's. It rose slowly and descended, it ran rippling arpeggios and lingered in flute-like trills; but it was colorless, impersonal, void of feeling. It was more like a flute than like the voice of a bird that pours out its soul for joy; it was perfect, but it was not moving. Only as the spirit of the desolate town--as of some lost soul, pure and passionless--did it find its note of appeal and Denver sighed and sat silent in the darkness. His thoughts strayed far away, to his boyhood in the mountains, to his wanderings from camp to camp; they leapt ahead to the problem that lay before him, the choice between the silver and gold treasures; and then, drowsy and oblivious, he left the voice still singing and groped to his bed in the cave. All night the prying pack-rats, dispossessed of their dwelling, raced and gnawed and despoiled his provisions; but when the day dawned Denver left them to do their worst, for his mind was on greater things. At another time, when he was not so busy, he would swing some rude cupboards on wires and store his food out of reach; but now he only stopped to make a hasty breakfast and started off up the trail. When the sun rose, over behind Apache Leap, and cast its black shadow among the hills, Denver was up on the rim-rock, looking out on the promised land that should yield him two precious treasures. The rim where he stood was uptilted and broken, a huge stratified wall like the edge of a layer cake or the leaves of some mighty book. They lay one upon the other, these ledges of lime and sandstone, some red, some yellow, some white; and, heaped upon the top like a rich coating of chocolate, was the brownish-black cap of the lava. In ages long past each layer had been a mud bank at the bottom of a tropic sea, until the weight of waters had pressed them down and time had changed them to stone. Then Mother Earth had breathed and in a slow, century-long heave, they had emerged from the bottom of the sea, there to be broken and shattered by the pent-up forces of the fire which was raging in her breast.