$6o BRITISH BIRDS* 
in the year, fo that the young ones have time to 
gain ftrength enough to accompany the parent birds 
in their diftant excurfions : They have been no- 
ticed at the Cape of Good Hope, and probably vi- 
fit the more remote regions of Alia. Swifts are 
almoft continually on the wing; they fly higher, 
and wheel with bolder wing than the Swallows, 
with which they never intermingle. The life of 
the Swift feems to be divided into two extremes ; 
the one of the moll violent exertion, the other of 
perfedt inaction ; they mull either fhoot through 
the air, or remain clofe in their holes ; they are 
feldom feen to alight ; but, if by any accident they 
fliould fall upon a piece of even ground, it is with 
difficulty they can recover themfelves, owing to 
the fliortnefs of their feet, and the great length of 
their wings. They are faid to avoid heat, and for 
this reafon pafs the middle of the day in their 
holes ; in the morning and evening they go out in 
quell of provifion; they then are feen in large 
flocks, defcribing an endlefs feries of circles upon 
circles, fometimes in clofe ranks, purfuing the di- 
rection of a llreet, and fometimes whirling round a 
large edifice, all fcreaming together; they often 
glide along without ilirring their wings, and on a 
fudden they move them with frequent and quickly 
repeated llrokes. Swifts build their nelts in ele- 
vated places ; lofty Iteeples and high towers are 
generally preferred ; fometimes they build under 
the arches of bridges, where, though the elevation 
