I remarked: "It is so; and here is a fact which science has scarcely suspected."
"Science, my lad, has been built upon many errors; but they are errors which it was good to fall into, for they led to the truth."
"What depth have we now reached?"
"We are thirty-five leagues below the surface."
"So," I said, examining the map, "the Highlands of Scotland are over our heads, and the Grampians are raising their rugged summits above us."
"Yes," answered the Professor laughing. "It is rather a heavy weight to bear, but a solid arch spans over our heads. The great Architect has built it of the best materials; and never could man have given it so wide a stretch. What are the finest arches of bridges and the arcades of cathedrals, compared with this far reaching vault, with a radius of three leagues, beneath which a wide and tempest-tossed ocean may flow at its ease?"
"Oh, I am not afraid that it will fall down upon my head. But now what are your plans? Are you not thinking of returning to the surface now?"
"Return! no, indeed! We will continue our journey, everything having gone on well so far."
"But how are we to get down below this liquid surface?"
"Oh, I am not going to dive head foremost. But if all oceans are properly speaking but lakes, since they are encompassed by land, of course this internal sea will be surrounded by a coast of granite, and on the opposite shores we shall find fresh passages opening."