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Show The Migration of Birds [line unreadable] to us, there is, perhaps, no question in geology more obscure. The long flights they take, and the unerring certainty with which they wing their way between the most distant places, arriving and departing at the same period year after year, are points in the history of bird of passage as mysterious as why they ??? a moonlight night to cross the mediterranean. But that their meterological instinct is not unerring is proved by the fact that thousands are every year drowned in their flight over the Atlantic and other oceans. Northern Africa and Western Asia are selected as winter quarters by most of them, and they may be often noticed on their way thither, to hang over towns at nights, puzzled, in spite of their experience, by the shifting lights of the streets and ???. The swallow or the nightingale may be sometimes delayed by unexpected circumstances. Yet it is rarely that they arrive or depart many days sooner or later, one year with another. Professor Newton considered that, were sea fowls satellites revolving round the earth their arrival could hardly be more surely calculated by an astronomer. "Foul weather or fair, heat or cold, the puffins? repair to some of their stations punctually on a given day, as if their movements were regulated by clockwork. The swiftness of flight which characterizes most birds enables them to cover a vast space in a brief time. The common black swift can fly 276 miles an hour, a speed which, if it could be maintained for less than half a day would carry the bird from its winter to its summer quarters. The large purple swift of America is capable, of even greater feats on the wing. The chimney swallow is slower, ninety miles an hour being about the limit of its powers; but the passenger pigeon of the United States can accomplish a journey of 1,000 miles between sunrise and sunset. It is also true, as the ingenious Herr Palmen has attempted to show that migrants during their long flights may be directed by an experience partly inherited and partly aquired by the individual bird. They often follow the coast line of continents, and invariably take, on their passage over the Mediterranean, one of three fronts. But this theory will not explain how they pilot themselves across the broad oceans, and is invalidated by the ?? familiar to every ornithologist that the old and young bird do not journey in company. Invariably, the young broods travel together, then come after an interval, the parents and usually the rear is brought up by the weakly, infirm, molting and broken winged. This is the rule in the autumn. The return journey is accomplished in the reverse order. The distance traveled seems, moreover, to have no relation to the size of the traveler. The Swedish blue throat performs its maternal functions among the Alps? and enjoys its winter holiday among the negroes? of Soudan?, while [unreadable]by -throated humming-bird [line unreadable]foundland and back again, though one would imagine that so delicate a little fairy would be more at home among the cacti and agaves of the Tierra Cal???? Than among the firs and fogs of the North. London Standard. |