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 of the two dreadful
springs of 1770 and 1771, they immediately 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 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:

. . . "Ante
Garrula quam tignis nidos suspendat hirundo."

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 gateways, 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
perpetual 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 long in
ascending and descending with security through so narrow a pass. When
hovering over the mouth of the funnel, the vibrations of her wings acting
on the confined air occasion a rumbling like thunder. It is not
improbable that the dam submits to this inconvenient situation so low in
the shaft, in order