The Chimney Swift 87 



see. During this splendid exhibition of flight there 

 occurs at short intervals the not altogether unmusical 

 sharp and rolling twitter. 



The nest of our swift is one of the most remarkable 

 structures to be found among our common birds. 

 It is usually placed in a chimney and is composed of 

 twigs quite uniform in length and size, woven into 

 a semicircular basket. As they seldom frequent the 

 ground, there has been considerable speculation con- 

 cerning the methods by which the swifts obtain their 

 nesting material. It has, however, been found that 

 instead of selecting material already scattered about 

 by the wind they break twigs from dead limbs or 

 trees, while in full flight. These twigs are held in 

 place upon the side of the chimney and where they 

 cross each other, by a very adhesive saliva secreted 

 by the birds. When the nest is completed it is quite 

 shallow as compared with that of a robin, being 

 usually not more than a fourth as deep, and having 

 none of the soft lining usually found in the nests of 

 other birds. On the contrary, the home of the swift 

 is rather rough within, while the entire surface, inside 

 and out, has a glistening appearance due to the 

 abundance of saliva which is used, not only at the 

 intersection of the twigs, but also scattered some- 

 what promiscuously over them. The saliva when dry 



