All four stood for some minutes, their ears on the stretch, without uttering a word. All at once Simon Ford exclaimed, “Well, I declare! Are trucks already running on the rails of New Aberfoyle?”
“Father,” replied Harry, “it sounds to me just like the noise made by waves rolling on the sea shore.”
“We can’t be under the sea though!” cried the old overman.
“No,” said the engineer, “but it is not impossible that we should be under Loch Katrine.”
“The roof cannot have much thickness just here, if the noise of the water is perceptible.”
“Very little indeed,” answered James Starr, “and that is the reason this cavern is so huge.”
“You must be right, Mr. Starr,” said Harry.
“Besides, the weather is so bad outside,” resumed Starr, “that the waters of the loch must be as rough as those of the Firth of Forth.”
“Well! what does it matter after all?” returned Simon Ford; “the seam won’t be any the worse because it is under a loch. It would not be the first time that coal has been looked for under the very bed of the ocean! When we have to work under the bottom of the Caledonian Canal, where will be the harm?”
“Well said, Simon,” cried the engineer, who could not restrain a smile at the overman’s enthusiasm; “let us cut our trenches under the waters of the sea! Let us bore the bed of the Atlantic like a strainer; let us with our picks join our brethren of the United States through the subsoil of the ocean! let us dig into the center of the globe if necessary, to tear out the last scrap of coal.”