It was a dark night, soft and soundless, with all things waiting in a mysterious hush. At the camp on the skirts of Mystery, Fair found Bossick ready. “Selwood’s conscious,” he told him quickly, “and his first thought was of his race for life. He said ‘they didn’t get me after all,’ and ‘I saw them driving Bossick’s steers into the face of Rainbow Cliff a mile from Sky Line.’ That’s the secret he discovered and for which they tried to kill him. “There’s some sort of opening in the rock face which connects with the subterranean passage that leads to Blue Stone Cañon, the desert range beyond, and finally to Marston on the railroad. That, gentlemen, is the secret of your disappearing cattle. Selwood said they always vanished at the same time Kate Cathrew drove her stock down to Cordova and out to the station—do you see? “The drive, coming down to the river, obliterated all tracks of those going up. Now that we know I think we’ve got the Sky Line rustlers dead to rights. There are twenty-one of us. “We’ll divide you; you, Bossick, going with your party up to Rainbow Cliff, and I striking up through the mysterious passage. This trip will take a long hard grill, for it is far up Blue Stone to the south, and none of us know the length of the underground way. “However, it must lead to some pocket not far from the cliff itself and on the inside. A gun-shot will locate us when we are ready for each other. Lord knows what we’ll find, or what the outcome will be. Let’s go.” And so it was that some time later Brand Fair with his posse passed close along the upper edge of Nance Allison’s ruined field and thought tenderly of the blue-eyed girl with her dogged courage and her simple faith, little dreaming that she was not safe in her bed in the cabin. The hours of the night wore on. Far down in the open reaches poor Dan was loping gallantly with open mouth and laboring lungs while the boy on his back drove him relentlessly on in a desperate attempt to overtake Fair, whom the sentries at Selwood’s ranch had described as on the way to Mystery Ridge. Crossing diagonally down, Rod Stone, safe away from Sky Line at last, made for Cordova with Minnie Pine behind him. Bossick, having the shortest journey of all, sat in a clump of pines with his men around him, and waited in strained silence for a distant shot.