It is a capital plan for finding out Madam How's secrets, to see what she might do in one place, and explain by it what she has done in another.

Suppose now, Madam How had orders to lift up the whole coast of Bournemouth only twenty or even ten feet higher out of the sea than it is now.

She could do that easily enough, for she has been doing so on the coast of South America for ages; she has been doing so this very summer in what hasty people would call a hasty, and violent, and ruthless way; though I shall not say so, for I believe that Lady Why knows best.

She is doing so now steadily on the west coast of Norway, which is rising quietly--all that vast range of mountain wall and iron-bound cliff--at the rate of some four feet in a hundred years, without making the least noise or confusion, or even causing an extra ripple on the sea; so light and gentle, when she will, can Madam How's strong finger be.
Now, if the mouth of that Chine at Bournemouth was lifted twenty feet out of the sea, one thing would happen,--that the high tide would not come up any longer, and wash away the cake of dirt at the entrance, as we saw it do so often.

But if the mud stopped there, the mud behind it would come down more slowly, and lodge inside more and more, till the Chine was half filled-up, and only the upper part of the cliffs continue to be eaten away, above the level where the springs ran out.