Joe, very carefully descending to the edge of the pool, measured the depth with his rod, when, finding it to be about four feet deep, we concluded that we would let well enough alone and end our survey at this point.
“Come on up, Joe,” I called out. “No use trying to go any farther: it’s too dangerous; we might get in over our heads.”
“Just a minute,” Joe replied. “Let’s see if we can’t find out which way the current sets in the pool.”
With that he took from his pocket a newspaper he had brought with him in case for any purpose we should need to make a “flare,” and crumpling this into a loose ball he set it afloat in the pool. Away it sailed, quickly at first, and then more slowly; and taking a sight on it as far as it was distinguishable, I found that the set of the current continued as before—due southeast.
“All right, Joe,” I cried. “Come on, now.” And Joe, giving me the end of his stick to take hold of, quickly rejoined me, when together we made our way carefully up the stream again, and climbing the rope, once more found ourselves out in the daylight.
“Now, Joe,” said I, “let us run our line and find out where it takes us.”
Having previously measured the distance from the point where the underground stream turned southeast to where the rope hung down, we now measured the same distance back again along the foot of the bluff, and thence, ourselves turning southeastward, we measured off a thousand feet. This brought us down to the lowest of the old lake-benches, about a hundred yards back of the house, when, sighting along the same line with the compass, we found that that faithful little servant pointed us straight to the entrance of the lower cañon.
“Then that does settle it!” cried Joe. “We’ve found the stream that keeps ‘the forty rods’ wet; there can be no doubt of it.”
It did, indeed seem certain that we had at last discovered the stream which supplied “the forty rods” with water; but allowing that we had discovered it:—what then? How much better off were we?
Beneath our feet, as we had now every reason to believe, ran the long-sought water-course, but between us and it was a solid bed of lava about forty feet thick; and how to get the water to the surface, and thus prevent it from continuing to render useless the meadow below, was a problem beyond our powers.