THE SWIFT. 273 



subject close attention, it was speedily shown to be a 

 gross absurdity; and now it is known for certain that 

 Swallows and Swifts retire every autumn to Northern 

 Africa for the purpose of spending the winter months. 

 The reason the Swift leaves us so early is said to be 

 because the bird is but of delicate constitution ; and, 

 certain it is, the cold winds and frosty nights of autumn 

 cannot be borne with comfort, if at all, by a bird ap- 

 proaching very closely in its structure to the Humming 

 Birds themselves. 



