clinging to the nest, supply them with food from 

 morning till night. For a time the young are fed on 

 the wing by their parents ; but the feat is done by so 

 quick and almost imperceptible a slight, that a per- 

 son must have attended very exactly to their motions 

 before he would be able to perceive it. As soon as 

 the young are able to shift for themselves, the dams 

 immediately turn their thoughts to the business of a 

 second brood, while the first flight, shaken off and 

 rejected by their nurses, congregate in great flocks, 

 and are the birds that are seen clustering and hover- 

 ing on sunny mornings and evenings round towers 

 and steeples, and on the roofs of churches and 

 houses. These congregatings usually begin to take 

 place about the first week in August ; and therefore 

 we may conclude that by that time the first flight is 

 pretty well over. The young of this species do not 

 quit their abodes all together ; but the more forward 

 birds get abroad some days before the rest. These 

 approaching the eaves of buildings, and playing 

 about before them, make people think that several 

 old ones attend one nest. They are often capricious 

 in fixing on a nesting-place, beginning many edifices, 

 and leaving them unfinished ; but when once a nest 

 is completed in a sheltered place, it serves for several 

 seasons. Those which breed in a ready-finished house 

 get the start in hatching of those that build new by 

 ten days or a fortnight. These industrious artificers 



are at their labours in the long days before four in 



198 



