Both men stopped rowing. The sound of the oars ceased, and the noise of the ripple from the oars. All listened intently. A hissing sound could be distinctly heard--a loud hissing sound which they had not noticed before, because, no doubt, of the gradualness of their approach and the noises made by the rowers.
"It's water--falling water. But, in the name of all the saints, where is it falling from, and how can we see it in the darkness? Give way, Tim."
The cave grew narrower still, and now there was barely room for the shortened oars. The sides of it came closer, the roof lowered until it was no more than an arm's length above the heads of the standing men. The bright patch grew higher and broader. The torch still burned. A dull whiteness shone on the rocks.
The luminous space now looked like a faintly-lighted sheet of glass. The hissing sound of the water had gathered intensity.
"I don't know what's beyond, but I'll risk going through if you are willing," cried Phelan, who was now in a state of almost frenzy from suppressed excitement.
"Go on--go on!" shouted O'Brien, who found it difficult to keep from jumping overboard.
"Go on!" repeated Alfred, who, too, was now standing up.
"Give way with a will!" shouted Phelan; and in a minute the boat shot through a thick sheet of foam and falling water, and glided into a placid pool.
For a moment the men were blinded by the foam and water, and could see nothing.
They rubbed their eyes, looked up obliquely, and were blinded once again.