Sid watched the glistening surface for some time, for all the day was his, and he had no appointment with anything or anybody. Gradually a loose needle detached itself from the ring of them about the hole and floated slowly _toward_ the brook! Sid’s interest at once arose mightily. He had assumed that this water was merely a backup from the brook, but that needle said, No! More of them detached and followed the pioneer across the water hole in the cleft. Out of such small beginnings do great things grow, in the woods! There was evidently a current between the hummocks, flowing toward the brook. If so, where did it come from? Sid asked himself. A spring, back in the depths of the cove, most likely. He explored the little dent in which he had camped, carefully. The broken and jagged strata of the walls had met here, jammed together by some prehistoric movement of the earth’s crust. It was _not_ the real plateau wall. The trees had taken advantage of the jumble of interlocking slabs, for a giant fir had effected a lodgment in the fissure, filled as it was with pockets of soil that had accumulated there. Sid eyed it with thrills of adventure and discovery running through him like wine. There _was_ no spring! The water came from farther back--somewhere! He raced back and crossed the brook, climbing the stratified walls of the canyon as high as he could. Squatting on a ledge, he peered upward to where the walls of the canyon towered into the cloudless blue far overhead. His eye followed the symmetrical column of the giant fir. The edges of the cove met and interlocked behind it, and for a considerable distance above its topmost spire. Then appeared a narrow cleft, a sort of fat man’s misery, extending to the top, and through it showed a thin seam of sky blue. The cove was a mere wall then, and something lay behind it--a blocked canyon perhaps. On fire with adventure, Sid eyed it speculatively, seeking a way to climb up to that cleft. Every ruin in the main canyon was known, and had been explored and rifled of its relics by ethnologists and tourists. Two or three centuries ago they had been inhabited by tribes of pueblo Indians, but when the Navaho, the Dene (deer hunters), as they called themselves, came down from the Far North they had attacked these villages and driven out all the pueblos in their neighborhood. How the Navaho _got_ down, from the neighborhood of Great Slave Lake where their kinsmen, the Dene, still live,--through the Blackfeet, the Shoshones, the Cheyennes and the Utes,--was a whole mystery in itself, but here they were, and had been since the times of the Spaniard. It accounted for the deserted state of all the cliff dwellings in the San Juan and Chaco Valley and Canyon Cheyo regions.