Now and then the solitude was relieved by the appearance of a horseman riding with flapping arms and jingling spurs up the pass; or again the silence was broken by the inconsequent bleating of a flock of sheep wandering in search of their scant pasturage or huddling together, an agitated mass of grimy wool, its outskirts painfully exposed to the sharp but well-intentioned admonitions of a somewhat irascible collie. Neither man nor beast took special note of the overgrown boy striding so confidently on his way, nor was one observer more likely than the other to guess what inspiring thoughts were animating the roughly clad, uncouth form. The boy's clothes were shabby and travel-stained, and over his shoulders was slung a canvas bag, its miscellaneous contents making sharp, angular protuberances on its surface. He had left the ranch with clothes and books enough to give the bag a pretty weight, and this he had unconcernedly increased by the insertion into the straining receptacle of many a "specimen" picked up by the way. For the eyes were keen and observant that looked out from under the strongly marked brows, and bits of fluorite and "fool's gold," and of rarer minerals as well, which had lain for years beside the road, noted as little by cowboy and ranchman and mountain tourist as by the redman whose feet first trod the pass, were destined to-day to start on their travels, enlisted in the service of Science. It must have been a daring specimen indeed that should have thought of resisting its fate when it came at the hands of Waldo Kean. There was a certain rough strength not only in the muscular frame, but in the face itself, with its rude features, its determined outlines, its heavy under-lip; and in the stiff black hair roughly clipped on the ample skull, growing in a bushy thatch above the keen dark eyes. It seemed but natural that just that type of boy should feel himself drawn to the study of the rocky foundation of things.