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southerly parts of Andalusia, where they can be no ways 

 influenced by any defect of heat ; or, as one might 

 suppose, defect of food. Are they regulated in their 

 motions with us by a failure of food, or by a propensity 

 to moulting, or by a disposition to rest after so rapid a 

 life, or by what ? This is one of those incidents in 

 natural history that not only baffles our searches, but 

 almost eludes our guesses 1 



These hirundines never perch on trees or roofs, and so 

 never congregate with their congeners. They are fearless 

 while haunting their nesting places, and are not to be 

 scared with a gun ; and are often beaten down with poles 

 and cudgels as they stoop to go under the eaves. Swifts 

 are much infested with those pests to the genus called 

 hippoboscse hirundinis ; and often wriggle and scratch 

 themselves, in their flight, to get rid of that clinging 

 annoyance. 



Swifts are no songsters, and have only one harsh 

 screaming note ; yet there are ears to which it is not 

 displeasing, from an agreeable association of ideas, since 

 that note never occurs but in the most lovely summer 

 weather. 



They never settle on the ground but through accident ; 

 and when down can hardly rise, on account of the short- 

 ness of their legs and the length of their wings : neither 

 can they walk, but only crawl ; but they have a strong 

 grasp with their feet, by which they cling to walls. Their 

 bodies being flat they can enter a very narrow crevice ; 

 and where they cannot pass on their beUies they will 

 turn up edgewise. 



The particular formation of the foot discriminates the 

 swift from all British hirundines ; and indeed from all 

 other known birds, the hirundo melba, or great white- 

 bellied swift of Gibraltar, excepted ; for it is so disposed 

 as to carry " omnes qiiatuor digitos anticos " all its four toes 



