OF SELBORNE. 277 



still naked and helpless. From whence we may con- 

 clude that birds whose way of life keeps them perpetu- 

 ally on the wing would not be able to quit their nest till 

 the end of the month. Swallows and martins, that have 

 numerous families, are continually feeding them every 

 two or three minutes ; while swifts, that have but two 

 young to maintain, are much at their leisure, and do 

 not attend on their nests for hours together. 



Sometimes they pursue and strike at hawks that 

 come in their way ; but not with that vehemence and 

 fury that swallows express on the same occasion. They 

 are out all day long in wet days, feeding about, and 

 disregarding still rain : from whence two things may be 

 gathered ; first, that many insects abide high in the air, 

 even in rain ; and next, that the feathers of these birds 

 must be well preened to resist so much wet. Windy, 

 and particularly windy weather with heavy showers, 

 they dislike ; and on such days withdraw, and are scarce 

 ever seen. 



There is a circumstance respecting the colour of 

 swifts, which seems not to be unworthy our attention. 

 When they arrive in the spring they are all over of a 

 glossy, dark soot colour, except their chins, which are 

 white ; but by being all day long in the sun and air, 

 they become quite weather-beaten and bleached before 

 they depart 2 , and yet they return glossy again in the 

 spring. Now, if they pursue the sun into lower lati- 

 tudes, as some suppose, in order to enjoy a perpetual 

 summer, why do they not return bleached? Do they 

 not rather, perhaps, retire to rest for a season, and at 

 that juncture moult and change their feathers, since all 

 other birds are known to moult soon after the season of 

 breeding. 



Swifts are very anomalous in many particulars, dis- 

 senting from all their congeners not only in the number 



2 Our swift departs before its moult, and when its plumage is at the 

 worst from wear and tear. Our summer visiters generally complete 

 their moult before they leave us, but not the Hirundinidte. W. Y. 



