That Apollyonic monster of the prime, the pterodactyl, did even better. Stretching on each little finger a lateen sail that would have served to waft a skiff across the Thames, it kept the rest of its hands for other uses. But what bearing has all this on the case of birds? Here is a whole sub-kingdom, as they call it, of the animal world which has unreservedly and irrevocably bartered one pair of its limbs for a flying-machine. The apparatus is made of feathers--a new invention, unknown to amphibian or saurian, whence obtained nobody can say--and these are grafted into the transformed frame of the old limbs. The bargain was worth making, for the winged bird at once soared away in all senses from the creeping things of earth, and became a more ethereal being; "like a blown flame, it rests upon the air, subdues it, surpasses it, outraces it; it is the air, conscious of itself, conquering itself, ruling itself." But the price was heavy. The bird must get through life with one pair of feet and its mouth. But this was all the bodily furniture of Charles François Felu, who, without arms, became a famous artist. A friend of mine, standing behind him in a _salon_ and watching him at work, saw him lay down his brush and, raising his foot to his head, take off his hat and scratch his crown with his great toe. My friend was nearly hypnotised by the sight, yet it scarcely strikes us as a wonder when a parrot, standing on one foot, takes its meals with the other. It is a wonder, and stamps the parrot as a bird of talent. A mine of hidden possibilities is in us all, but those who dig resolutely into it and bring out treasure are few. And let us note that the art of standing began with birds. Frogs sit, and, as far as I know, every reptile, be it lizard, crocodile, alligator, or tortoise, lays its body on the ground when not actually carrying it. And these have each four fat legs. Contrast the flamingo, which, having only two, and those like willow wands, tucks up one of them and sleeps poised high on the other, like a tulip on its stem. Note also that one toe has been altogether discarded by birds as superfluous. The germ, or bud, must be there, for the Dorking fowl has produced a fifth toe under some influence of the poultry-yard, but no natural bird has more than four. Except in swifts, which never perch, but cling to rocks and walls, one is turned backwards, and, by a cunning contrivance, the act of bending the leg draws them all automatically together. So a hen closes its toes at every step it takes, as if it grasped something, and, of course, when it settles down on its roost, they grasp that tight and hold it fast till morning. But to birds that do not perch this mechanism is only an encumbrance, so many of them, like the plovers, abolish the hind toe entirely, and the prince of all two-legged runners, the ostrich, has got rid of one of the front toes also, retaining only two.