Well, my dear boy, the true causes of it have only been known for the last thirty or forty years; and we English are, as good King Alfred found us to his sorrow a thousand years ago, very slow to move, even when we see a thing ought to be done. Let us hope that in this matter--we have been so in most matters as yet--we shall be like the tortoise in the fable, and not the hare; and by moving slowly, but surely, win the race at last. But now think for yourself: and see what you would do to save these people from being poisoned by bad water. Remember that the plain question is this--The rainwater comes down from heaven as water, and nothing but water. Rainwater is the only pure water, after all. How would you save that for the poor people who have none? There; run away and hunt rabbits on the moor: but look, meanwhile, how you would save some of this beautiful and precious water which is roaring away into the sea. * * * * * Well? What would you do? Make ponds, you say, like the old monks' ponds, now all broken down. Dam all the glens across their mouths, and turn them into reservoirs. "Out of the mouths of babes and sucklings"--Well, that will have to be done. That is being done more and more, more or less well. The good people of Glasgow did it first, I think; and now the good people of Manchester, and of other northern towns, have done it, and have saved many a human life thereby already. But it must be done, some day, all over England and Wales, and great part of Scotland. For the mountain tops and moors, my boy, by a beautiful law of nature, compensate for their own poverty by yielding a wealth which the rich lowlands cannot yield. You do not understand? Then see. Yon moor above can grow neither corn nor grass. But one thing it can grow, and does grow, without which we should have no corn nor grass, and that is--water. Not only does far more rain fall up there than falls here down below, but even in drought the high moors condense the moisture into dew, and so yield some water, even when the lowlands are burnt up with drought. The reason of that you must learn hereafter. That it is so, you should know yourself. For on the high chalk downs, you know, where farmers make a sheep-pond, they never, if they are wise, make it in a valley or on a hill-side, but on the bleakest top of the very highest down; and there, if they can once get it filled with snow and rain in winter, the blessed dews of night will keep some water in it all the summer through, while the ponds below are utterly dried up. And even so it is, as I know, with this very moor. Corn and grass it will not grow, because there is too little "staple," that is, soluble minerals, in the sandy soil. But how much water it might grow, you may judge roughly for yourself, by remembering how many brooks like this are running off it now to carry mere dirt into the river, and then into the sea. But why should we not make dams at once; and save the water?