"From the gizzard mills of the earthworm to the great earth mills of the sea, all are--most evidently--parts of one great system." (In the picture on the left an earthworm has been laid open to show its grinding apparatus.)] So we find a wonderful variety of things working together in making and feeding the soil that feeds the world: mountains and pebbles, volcanoes and lichens, the breath of the living and the bones of the dead; the sun, the winds, the sea, the rains; the farmers with four feet, the farmers with six feet; the swallow building her nest under the eaves, the earthworms burrowing under our feet, each bent on its own affairs, to be sure, but at the same time each helping to carry on the great business of the universe. From the little gizzard mills of the earthworm to the great earth mills of the sea, that renew the soil for the ages yet to come, all are--most evidently--parts of one great system; are together helping to work out great purposes in the advance of men and things; purposes which require that "While the earth remaineth, summer and winter, seed-time and harvest, shall not cease." HIDE AND SEEK IN THE LIBRARY As I said, most people not only think that they're smarter than their fellow animals, but when you point out to them how clever some of these other animals are, they say: "Oh, _that's_ just instinct!" As if animals don't think and learn by experience, and all, just as we do! You look up "instinct" in the encyclopædia, and you'll see. Then read Long's "Wood Folk at School." There's really a lot more fun in shooting animals with a camera than with a shotgun or a rifle. Did you ever try it? "Hunting with a Camera" in "The Scientific American Boy at School," by Bond, will tell you how to get the best results. Other good pointers on animal photography will be found in Verrill's "Boy Collector's Hand Book" ("Photographing Wild Things") and in "On the Trail," by A. B. and Lina Beard. And if you ever feel like killing a bird "just for fun," read in the diary of "Opal" about the farmer boy who shot the little girl's pet crow; it was "only a crow," he said, and he wanted to see if he could hit it. That will cure you, I think. The diary of "Opal" reads like a fairy-tale, but it's all true, and although it was written--every word of it--by a little girl of seven, it is one of the most remarkable books that anybody ever wrote. The crow's name, by the way, was "Lars Porsina of Clusium." The little girl used to give her pets names like that.