156 
THE NATURAL HISTORY 
[LETT. 
It is wortli 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 
ont-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 Ladib 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 slmft of an old 
well, through which chalk had been formerly drawn up for the 
purpose of manure : but in general with us this hiritnclo breeds 
in chimneys ; and loves to haunt those stacks where there is a 
constant fire, no doubt for the sake of warmth. ]N'ot 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 
