A Book on Birds 



himself, the twigs composing it being shied 

 together by him Hke wicker-work with a 

 gelatinous substance, secreted in his mouth, 

 and fastened rudely, without any Hning 

 of grass or feathers, against the inside of 

 the chimney — somewhat as a semi-circular 

 fungus to the bark of a tree. 



In earlier times the Swift made his home 

 in caves and hollow trunks of the forest, 

 and resorted to chimneys when these ap- 

 peared because, probably, like many other 

 birds, he is of a social disposition and seeks 

 proximity to human habitations; and for 

 the further reason, no doubt, that he found 

 as caves and hollow trunks grew fewer 

 with the march of civilization, the number 

 of large, well-warmed and easily accessible 

 chimneys continually increased. 



One of the most entertaining sights 

 imaginable is to watch a flock of Swifts at 

 evening in early autumn, circling some one 

 of these towering piles of brick or stone for 

 an hour or so after sunset, in a wild, merry- 

 go-round flight, and finally pouring down 

 into it in a great stream. 



[64] 



