were really very good people, and very kind to me, I shall not tell you
what the name of the place is.

Of course after that I could do no less than ask Madam How, very civilly,
how she made earthquakes in that particular place, hundreds of miles away
from any burning mountain? And this was the answer I _thought_ she gave,
though I am not so conceited as to say I am sure.

As I had come up the valley I had seen that the cliffs were all beautiful
gray limestone marble; but just at this place they were replaced by
granite, such as you may see in London Bridge or at Aberdeen. I do not
mean that the limestone changed to granite, but that the granite had
risen up out of the bottom of the valley, and had carried the limestone
(I suppose) up on its back hundreds of feet into the air. Those caves
with the waterfalls pouring from their mouths were all on one level, at
the top of the granite, and the bottom of the limestone. That was to be
expected; for, as I will explain to you some day, water can make caves
easily in limestone: but never, I think, in granite. But I knew that
besides these cold springs which came out of the caves, there were hot
springs also, full of curious chemical salts, just below the very house
where I was in. And when I went to look at them, I found that they came
out of the rock just where the limestone and the granite joined. "Ah," I
said, "now I think I have Madam How's answer. The lid of one of her
great steam boilers is rather shaky and cracked just here, because the
granite has broken and torn the limestone as it lifted it up; and here is
the hot water out of the boiler actually oozing out of the crack; and the
earthquake I heard last night was simply the steam rumbling and thumping
inside, and trying to get out."

And then, my dear child, I fell into a more serious mood. I said to