176 NATURAL HISTORY OF SELBORNE. 



tall buildings, churches, and steeple;-, 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 instance 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 ob- 

 servation. 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. 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 opportunity 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 its 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. 



This hirundo differs widely from its congeners in laying invariably 

 but two eggs at a time, which are milk-white, long, and peaked at 

 the small end ; whereas the other species lay at each brood from 

 four to six. It is a most alert bird, rising very early, and retiring to 

 roost very late ; and is on the wing in the height of summer at least 

 sixteen hours. In the longest days it does not withdraw to rest till 

 a quarter before nine in the evening, being the latest of all day-birds. 

 Just before they retire whole groups of them assemble high in the 

 air, and squeak, and shoot about with wonderful rapidity. But this 

 bird is never so much alive as in sultry thundry weather, when it 

 expresses great alacrity, and calls forth all its powers. In hot 

 mornings, several, getting together in little parties, dash round the 



