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270 "There is now a continuous straggling stream, forming ever so many little troops. The first bird of one troop tends to become the last of the one preceding it, and the last one the leader of the troop following. Then come numbers, flying in a very irregular and widely disseminated formation, yet together in a certain sense. There is much of rising and sinking and again floating upwards, of twists and twirls and sudden, dashing swoops downwards, from side to side, like the car of a falling balloon; two birds often pursuing each other in this way.

"And now come two great bands, one flying all abreast, as before described, the other forming a great, irregular, quasi-circular rook-storm. Leadership in the latter case would be an impossibility; in the former I see no sign of it. All these birds, though at a fair height, are flapping steadily along in the usual prosaical manner; through them, and far above—at a very great height indeed, the highest I have yet seen, and far beyond anything I should have imagined—I see another band gliding smoothly, majestically on, with scarce an occasional stroke of the eagle-spread pinions. The one black band of birds seen through the others, far, far above them, has a curious, an inspiring effect."

Rooks, when in continued progress, either fly with a constant, steady flapping of the wings, in a somewhat laboured way, though often fairly fast, or they sail along with wings outspread, and flapping only from time to time—this last, however, only when they are at a considerable height. A crowd of rooks, indeed, in the higher regions of air present a very different appearance to what they do when they fly