We were passing through rocks of the transition or silurian [1] system.
"It is evident," I cried, "the marine deposits formed in the second period, these shales, limestones, and sandstones.

We are turning away from the primary granite.

We are just as if we were people of Hamburg going to Luebeck by way of Hanover!" I had better have kept my observations to myself.

But my geological instinct was stronger than my prudence, and uncle Liedenbrock heard my exclamation.
"What's that you are saying ?" he asked.
"See," I said, pointing to the varied series of sandstones and limestones, and the first indication of slate.
"Well ?" "We are at the period when the first plants and animals appeared." "Do you think so ?" "Look close, and examine." I obliged the Professor to move his lamp over the walls of the gallery.

I expected some signs of astonishment; but he spoke not a word, and went on.
Had he understood me or not?
Did he refuse to admit, out of self-love as an uncle and a philosopher, that he had mistaken his way when he chose the eastern tunnel?
or was he determined to examine this passage to its farthest extremity?
It was evident that we had left the lava path, and that this road could not possibly lead to the extinct furnace of Snaefell.
Yet I asked myself if I was not depending too much on this change in the rock.