I don’t suppose the maddest geologist under such circumstances would have studied the nature of the rocks that we were passing. I am sure I did trouble my head about them. Pliocene, Miocene, Eocene, Cretaceous, Jurassic, Triassic, Permian, Carboniferous, Devonian, Silurian, or Primitive was all one to me. But the Professor, no doubt, was pursuing his observations or taking notes, for in one of our halts he said to me:

“The farther I go the more confidence I feel. The order of these volcanic formations affords the strongest confirmation to the theories of Davy. We are now among the primitive rocks, upon which the chemical operations took place which are produced by the contact of elementary bases of metals with water. I repudiate the notion of central heat altogether. We shall see further proof of that very soon.”

No variation, always the same conclusion. Of course, I was not inclined to argue. My silence was taken for consent and the descent went on.