There was there a sort of depression in the water, as if it was suddenly lost in some fissure in the ground.
Cyrus Harding listened; placing his ear to the level of the lake, he very distinctly heard the noise of a subterranean fall.
"There," said he, rising, "is the discharge of the water; there, doubtless, by a passage in the granite cliff, it joins the sea, through cavities which we can use to our profit. Well, I can find it!"
The engineer cut a long branch, stripped it of its leaves, and, plunging it into the angle between the two banks, he found that there was a large hole one foot only beneath the surface of the water. This hole was the opening so long looked for in vain, and the force of the current was such that the branch was torn from the engineer's hands and disappeared.
"There is no doubt about it now," repeated Harding. "There is the outlet, and I will lay it open to view!"
"How?" asked Gideon Spilett.
"By lowering the level of the lake water three feet."
"And how will you lower the level?"
"By opening another outlet larger than this."
"At what place, Cyrus?"
"At the part of the bank nearest the coast."
"But it is a mass of granite!" observed Spilett.
"Well," replied Cyrus Harding, "I will blow up the granite, and the water escaping, will subside, so as to lay bare this opening———"
"And make a waterfall, by falling on to the beach," added the reporter.
"A fall that we shall make use of!" replied Cyrus.
"Come, come!"
The engineer hurried away his companion, whose confidence in Harding was such that he did not doubt the enterprise would succeed. And yet, how was this granite wall to be opened without powder, and with imperfect instruments? Was not this work upon which the engineer was so bent above their strength?
When Harding and the reporter entered the Chimneys, Herbert and Pencroft were unloading their raft of wood. "The woodmen have just finished, captain," said the sailor, laughing, "and when you want masons———"
