156 THE NATURAL HISTORY [LETT. 



It is worth remarking that these birds are seen first about 

 lakes and mill-ponds ; and it is also very particular, that if 

 these early visitors happen to find frost and snow, as was the 

 case in the two dreadful springs of 1770 and 1771, they imme- 

 diately withdraw for a time. A circumstance this much more 

 in favour of hiding than migration ; since it is much more 

 probable that a bird should retire to its hybernaculum just at 

 hand, than return for a week or two only to warmer latitudes. 



The swallow, though called the chimney-swallow, by no 

 means builds altogether in chimneys, but often within barns and 

 'out-houses, against the rafters ; and so she did in Virgil's time : 

 Garrula quam tignis nidos suspendat hirundo." " The twitter- 

 ing swallow hangs its nest from the beams." 



In Sweden she builds in barns, and is called Ladu swala, the 

 barn-swallow. Besides, in the warmer parts of Europe there 

 are no chimneys to houses, except they are English built : in 

 these countries she constructs her nest in porches, and gate- 

 ways, and galleries, and open halls. 



Here and there a bird may affect some odd, peculiar place ; 

 as we have known a swallow build down the shaft of an old 

 well, through which chalk had been formerly drawn up for the 

 purpose of manure : but in general with us this hirundo breeds 

 in chimneys ; and loves to haunt those stacks where there is a 

 constant fire, no doubt for the sake of warmth. Not that it can 

 subsist in the immediate shaft where there is a .fire ; but prefers 

 one adjoining to that of the kitchen, and disregards the per- 

 petual smoke of that funnel, as I have often observed with some 

 degree of wonder. 



Five or six or more feet down the chimney does this little bird 

 begin to form her nest, about the middle of May, which consists, 

 like that of the house-martin, of a crust or shell composed of 

 dirt or mud, mixed with short pieces of straw to render it tough 

 and permanent : with this difference, that whereas the shell of 

 the martin is nearly hemispheric, that of the swallow is open at 

 the top, and like half a deep dish : this nest is lined with fine 

 grasses, and feathers which are often collected as they float in 

 the air. 



Wonderful is the address which this adroit bird shows all day 



