When the boys came to the full light of day, they saw the sun shining on a pool of clear, glistening water, which lay in a cup-like depression in a narrow canyon sloping up to the north. Judging from the time they had been in the passage, Clay concluded that they were at least six hundred feet from the river, and not far from two hundred feet above it.
The canyon in which they found themselves was little better than a deep wrinkle in the massive formation of the west shore, but it seemed to point the way to an exit up stream. After wading the pool, which was supplied by springs in the walls, they gained a dry bottom and proceeded northward, still climbing.
“If this crack in the earth keeps on this way for a mile or two,” Clay suggested, “we will come out on the wide shelf that divides the west wall not far south of the old mine. From there we can signal to the boys who went up there, and they can come in the motor boat and get us. We never can swim across. In the first place, it is too far; and in the second, the current is too strong.”
“You heard the story Case and Alex told about the sunburst on the wall?” asked Don.
“I thought that rather fishy!” Clay replied.
“We’ll soon have a chance to find out whether it is or not,” Don continued, “for we’ll come out on the shelf near the place they described—if we come out on the river bank at all.”
“But we’d be too close to the sunburst and the ‘X’ to see them,” Clay remarked. “You have to look at such large things from a distance in order to discern them at all.”
“If we can get there some day by ten o’clock,” Don hastened to say, “we can mark where the line of sunlight lies, and that will help some. But,” he added, with a frown, “I guess we’re not going to get out to the river wall by following this old scratch in the earth! Here’s where it turns to the west! Now, what about it?”
“It may bring us to the top, anyway!” Clay said, encouragingly.
But it did not bring them to the top, for directly it ran into a cavern not unlike that which the boys had passed through! Disgusted and disheartened, the lads took to the tunnel and pressed on in the darkness. The only satisfaction they felt was that they were still going up.