As illustrating a remarkable quality of flight, the case of the kestrel or windhover may be taken. On a summer day one may frequently see this pretty little falcon standing against the blue in what seems an absolutely stationary position, as though suspended by an invisible silken thread. But let a meadow-mouse so much as move and it drops to the sward in an instant. As has been already stated, there is perhaps nothing more wonderful in nature than the power of flight, and no subject which yields such startling facts upon investigation. "The way of an eagle in the air" is one of those things of which Solomon expressed himself ignorant; and there is something truly marvellous in the mechanism which controls the scythe-like sweep of wings peculiar to most birds of prey. The noblest of these, the peregrine, has been seen flying over mid-Atlantic; and Henry IV., King of France, had a falcon which escaped from Fontainebleau, and in twenty-four hours after was found in Malta, a space computed to be not less than 1,350 miles, a velocity equal to fifty-six miles an hour, supposing the hawk to have been on the wing the whole time. Indeed, in Montagu's opinion, the rapidity with which hawks and other birds occasionally fly is probably not less than at the rate of a hundred and fifty miles an hour, when either pursued or pursuing. The speed of flight of the peregrine cited above is about that of our best trained pigeons; and it may here be remarked that the flight of these two (otherwise dissimilar) birds very much resembles each other. The beautiful swallow-tailed kite has accomplished the feat of flying across the whole Atlantic Ocean, which is hardly to be wondered at seeing its vast powers of flight. Lieuwenholk relates an exciting chase which he saw in a menagerie about one hundred feet long between a swallow and a dragon-fly (Mordella). The insect flew with incredible speed, and wheeled with such address that the swallow, notwithstanding its utmost efforts, completely failed to overtake and capture it. The best speed of a railway train is only a little more than half the velocity of the golden eagle, the flight of which often attains to the rate of one hundred and forty miles an hour. Of all birds, the condor mounts highest into the atmosphere. Humboldt describes the flight of this bird in the Andes to be at least twenty thousand feet above the level of the sea. Upon one occasion a falcon was observed to cut a snipe right in two, with such strength and speed did it cut down its prey. Sparrow-hawks and merlins have not unfrequently been known to crash through thick plate-glass windows when in pursuit of prey, or at caged birds.