guished at once by the conspicuous white rump patch, and pure 
white underparts. These are the signs by which they may be 
recognized when on the wing—and they are more often seen thus 
than at rest. The sand-martin is a much smaller bird, has a less 
markedly forked tail, and is of a uniform pale brown above, and 
white below, but with a brown band across the chest. The swift 
is not even related to the swallow-tribe. On the wing—and very 
few people ever see him otherwise—he is very different. The wing- 
beat is extremely rapid and intermittent. While in its shape the 
wing differs in its extreme length and narrowness. The flight is 
extremely swift—hence the name of the bird. Not its least 
impressive feature is its wonderful flexibility. Who has not 
watched, with delight, a troop of these birds sweeping down the 
village street, now skimming the ground, now sweeping upward 
and away, round the church tower, accompanied by wild, 
exultant screams, as though they were bubbling over with vitality. 
When high up they look like so many animated bows and arrows— 
the arrows being, perhaps, somewhat short and thick. The swift, 
it is worth remembering, is a near kinsman of the humming-bird, 
which also has a long narrow wing. Both alike agree in this 
peculiarity—an upper arm bone of excessive shortness, and a hand 
of excessive length. No other birds approach them in this. The 
only other bird which has wings quite so ribbon-like, when 
extended, is the albatross—one of our rarest British birds. But 
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