In one great flood the truth swept upon him, the truth of what lay behind the cataract, of where John Ball had gone!  For he held in his hands an eyeless creature of another world, a world hidden in the bowels of the earth itself, a proof that beyond the fall was a great cavern filled with the mystery and the sightless things of eternal night, and that in this cavern John Ball found his food and made his home!

CHAPTER XVII

IN A SUBTERRANEAN WORLD

When Mukoki and Wabigoon returned half an hour later the hot-stone biscuits were still unbaked.  The fire was only a bed of coals.  Beside it sat Rod, the strange fish upon the ground at his feet.  Before Mukoki had thrown down the pack of meat which he was carrying he was showing them this fish.  Quickly he related what had happened.  He added to this some of the things which he had thought while sitting by the fire.  The chief of these things were that just behind the cataract was the entrance to a great cavern, and that in this cavern they would not only find John Ball, but also the rich storehouse of that treasure of which they, had discovered a part in the pool.

And as the night lengthened there was little talk about the gold and much about John Ball.  Again and again Rod described the madman’s visit, the trembling, pleading voice, the offering of the fish, the eager glow that had come into the wild eyes when he talked to him and called him by name.  Even Mukoki’s stoic heart was struck by the deep pathos of it all.  The mad hunter no longer carried his gun.  He no longer sought their lives.  In his crazed brain something new and wonderful was at work, something that drew him to them, with the half-fear of an animal, and yet with growing trust.  He was pleading for their companionship, their friendship, and deep down in his heart Rod felt that the spark of sanity was not completely gone from John Ball.

When the three adventurers retired to their blankets in the cedar shelter it was not the thought of gold that quickened their blood in anticipation of the morning.  The passing of an age would not dull the luster of what they had come to seek.  It would wait for them.  The greatest of all things—­the sympathy of man for man—­had stilled that other passion in them.  John Ball’s salvation, and not more gold, was the day’s work ahead of them now.

With the dawn they were up, and by the time it was light enough to see they were ready for the exploration of whatever was hidden behind the fall.  In a rubber blanket Wabigoon wrapped a rifle and half a dozen pine torches.  Mukoki carried a quantity of cooked meat.  Standing on the edge of the pool Rod pointed into the falling torrent.

“He dived straight under,” he said.  “The opening to the cavern is directly behind the shoot of falling water.”

Wabi placed his hat and coat upon a rock.

“I’ll try it first.  Wait until I come back,” he said.