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an agreeable allociation of ideas, fince that note never 
occurs but in the moft lovely fiimmer weather. They 
never fettle on the ground but through accident, and 
when down can hardly rife, on account of the fliortnefs of 
their legs and the length of their wings : neither can they 
walk, but only crawl; but they have a flrong gralp with 
their feet, by which they cling to walls. Their bodies being 
flat, th^y can enter into a very narrow crevice ; and where 
they cannot pafs on their bellies, they will turn up edge- 
ways. The particular formation of the fwift’s foot dif- 
criminates that bird from all the Britifli hirundines^ and 
indeed from all other known birds, the hirundo m.elba, or 
gi eat white-bellied fwift of Gibraltar, excepted ; for it is 
lo difpofed as to carry omnes quatuor digitos anticos. Be- 
fides, the leaf! toe, which fliould be the back toe, con- 
lifls only of one bone alone ; and the other three only of 
two apiece. A conftru<ftion mod: rare and peculiar; but' 
nicely adapted to the purpofes in which their feet are 
employed. This, and fome peculiarities attending the' 
nodrils and under mandible, have induced a difcerning' 
naturalidr^; to fuppofe, thaf this fpecies might conditute' 
a genus per fe. In London, a party of fwifts frequent^ 
the Tower, playing and feeding over the river jud be-*^ 
low the bridge : others haunt fome of the churches of 
the Borough next the fields;- but do nor venture, like'.. 
the houfe-martin, into the clofe, crowded qiarts of the' 
town. The Swedes have bedowed a very pertinent^ 
(a) JOHN ANTONY scoPoCi, of Carhlola, M. D - ^ 
VOL.LXV. . pp 
