But, even after the completion of his education, when he is independent of his parents, and quick and sure as they at capturing fishes down in their own dim element, is it not still a puzzle and a mystery that such a thing can be done? And here I speak not only of the little grebe, but of all birds that dive after fishes, and pursue and capture them in fresh or salt water. We see how a kingfisher takes his prey, or a tern, or gannet, or osprey, by dropping upon it when it swims near the surface; he takes his fish by surprise, as a sparrow-hawk takes the bird he preys upon. But no specialisation can make an air-breathing, feathered bird an equal of the fish under water. One can see at a glance in any clear stream that any fish can out-distance any bird, darting off with the least effort so swiftly as almost to elude the sight, while the fastest bird under water moves but little faster than a water-rat. [Sidenote: Fascination] The explanation, I believe, is that the paralysing effect on many small, persecuted creatures in the presence of, or when pursued by, their natural enemies and devourers, is as common under as above the water. I have distinctly seen this when watching fish-eating birds being fed at the Zoological {263} Gardens in glass tanks. The appearance of the bird when he dives strikes an instant terror into them; and it may then be seen that those which endeavour to escape are no longer in possession of their full powers, and their efforts to fly from the enemy are like those of the mouse and vole when a weasel is on their track, or of a frog when pursued by a snake; while others remain suspended in the water, quite motionless, until seized and swallowed. {264} CHAPTER XIII Morning in the valley--Abundance of swifts--Unlikeness to other birds--Mayfly and swallows--Mayfly and swift--Bad weather and hail--Swallows in the rain--Sand-martins--An orphaned blackbird--Tamed by feeding--Survival of gregarious instinct in young blackbirds--Blackbird's good-night--Cirl buntings--Breeding habits and language--Habits of the young--Reed-bunting--Beautiful weather--The oak in August. [Sidenote: Swifts]