There was no doubt in Harlan's mind that John Haydon was the mysterious "Chief"--the man who had sent into Lane Morgan's breast the bullet that had ultimately killed him; and there was no doubt that some powerful, secret force was at work in the country, and that the force was directing its attention to the Rancho Seco and the defenseless girl who was at the nominal head of it. For some reason the secret force had killed her father, had isolated the ranch, had encompassed it with enemies, and was working slowly and surely to enmesh the girl herself. Harlan was convinced that one of the motives behind the subtle aggressions of the men was a yearning for the gold that Morgan had left--in fact the presence of Dolver and Laskar at Sentinel Rock--and Morgan's word to him about the gold--provided sufficient evidence on that score. They had watched Morgan; they suspected he was taking gold to Pardo to have it assayed, and they had killed him in the hope of finding something on his person which would reveal to them where he had hidden the rest of it. One other motive was that of the eternal, ages-old passion of a man for woman. Evidence of that passion had been revealed to Harlan at Lamo, by the attack on Barbara by Deveny's hireling--Higgins; by the subtle advances of John Haydon. It seemed to Harlan that all of these men had been--and were--equally determined to possess the girl. And yet back of it all--behind that which had been rendered visible by the actions of the man and by Harlan's own deductions--was something else--something stealthy and hidden; a secret threat of dire things to come--a lingering promise of trickery. Standing at one of the gates of the corral upon the third morning following Linton's departure, Harlan considered this phase of the situation. He felt the hidden threat of something sinister that lurked in the atmosphere. It was all around him. It seemed to lie secreted in the yawning space that engulfed the Rancho Seco--south, north, and east. From the haze that stretched into the unending distance westward it seemed to come, bearing its whispered promise. The solemn hills that flanked the wide stretches of Sunset Valley seemed to hint of it--somberly. Mystery was in the serene calm that seemed to encompass the big basin; from the far reaches westward, in the misty veil that seemed to hang from the far-flung shafts of sunlight that penetrated the fleecy clouds, came the sinister threat--the whole section seemed to pulse with it. And yet Harlan knew there could be no mystery except the mysteries of men. Nature was the same here as in any other section of the world, and her secrets were not more profound than usual.