To me the longest railroad journey, instead of being stupid, is like continually turning over the leaves of a wonderful book, or looking at wonderful pictures of old worlds which were made and unmade thousands of years ago.

For I keep looking, not only at the railway cuttings, where the bones of the old worlds are laid bare, but at the surface of the ground; at the plains and downs, banks and knolls, hills and mountains; and continually asking Mrs.
How what gave them each its shape: and I will soon teach you to do the same.

When you do, I tell you fairly her answer will be in almost every case, "Running water." Either water running when soft, as it usually is; or water running when it is hard--in plain words, moving ice.
About that moving ice, which is Mrs.How's stronger spade, I will tell you some other time; and show you, too, the marks of it in every gravel pit about here.

But now, I see, you want to ask a question; and what is it?
Do I mean to say that water has made great valleys, such as you have seen paintings and photographs of,--valleys thousands of feet deep, among mountains thousands of feet high?
Yes, I do.

But, as I said before, I do not like you to take my word upon trust.