76 NATURAL HISTORY OF SELBORNE 



middle of May, and I have remarked, from eggs taken, 

 that they have sat hard by the ninth of June. In general 

 they haunt tall buildings, churches, and steeples, and breed 

 only in such : yet in this village some pairs frequent the 

 lowest and meanest cottages, and educate their young 

 under those thatched roofs. We remember but one in- 

 stance where they breed out of buildings, and that is in 

 the sides of a deep chalk-pit near the town of Odiham, in 

 this county, where we have seen many pairs entering 

 the crevices, and skimming and squeaking round the 

 precipices. 



As I have regarded these amusive birds with no small 

 attention, if I should advance something new and peculiar 

 with respect to them, and different from all other birds, I 

 might perhaps be credited ; especially as my assertion is the 

 result of many years exact observation. The fact that I 

 would advance is, that swifts tread, or copulate, on the 

 wing : and I would wish any nice observer, that is startled 

 at this supposition, to use his own eyes, and I think he will 

 soon be convinced. 1 In another class of animals, viz., the 

 insect, nothing is so common as to see the different species 

 of many genera in conjunction as they fly. The swift is 

 almost continually on the wing ; and as it never settles on 

 the ground, on trees, or roofs, would seldom find oppor- 

 tunity for amorous rites, was it not enabled to indulge 

 them in the air. If any person would watch these birds 

 of a fine morning in May, as they are sailing round at a 

 great height from the ground, he would see, every now and 

 then, one drop on the back of another, and both of them 

 sink down together for many fathoms with a loud piercing 

 shriek. This I take to be the juncture when the business 

 of generation is carrying on. 



As the swift eats, drinks, collects materials for it's nest, 

 and, as it seems, propagates on the wing, it appears to live 

 more in the air than any other bird, and to perform all 

 functions there save those of sleeping and incubation. 



1 See vol. i. p. 101. [R. B. S.] 



