SELBORNE, _Jan._ 29_th_, 1774.
Dear Sir,--The house-swallow, or chimney-swallow, is undoubtedly the
first comer of all the British hirundines; and appears in general on or
about 13th April, as I have remarked from many years' observation. Not
but now and then a straggler is seen much earlier; and, in particular,
when I was a boy I observed a swallow for a whole day together on a sunny
warm Shrove Tuesday; which day could not fall out later than the middle
of March, and often happened early in February.
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 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 to secure her broods from rapacious birds, and
particularly from owls, which frequently fall down chimneys, perhaps in
attempting to get at these nestlings.
The swallow lays from four to six white eggs, dotted with red specks; and
brings out her first brood about the last week in June, or the first week
in July. The progressive method by which the young are introduced into
life is very amusing: first, they emerge from the shaft with difficulty
enough, and often fall down into the rooms below: for a day or so they
are fed on the chimney-top, and then are conducted to the dead leafless
bough of some tree, where, sitting in a row, they are attended with great
assiduity, and may then be called _perchers_. In a day or two more they
become _flyers_, but are still unable to take their own food; therefore
they play about near the place where the dams are hawking for flies; and,
when a mouthful is collected, at a certain signal given, the dam and the
nestling advance, rising towards each other, and meeting at an angle; the
young one all the while uttering such a little quick note of gratitude
and complacency, that a person must have paid very little regard to the
wonders of Nature that has not often remarked this feat.
The dam betakes herself immediately to the business of a second brood as
soon as she is disengaged from her first; which at once associates with
the first broods of house-martins; and with them congregates, clustering
on sunny roofs, towers, and trees. This hirundo brings out her second
brood towards the middle and end of August.
All the summer long is the swallow a most instructive pattern of
unwearied industry and affection; for from morning to night, while there
is a family to be supported, she spends the whole day in skimming close
to the ground, and executing the most sudden turns and quick evolutions.
Avenues, and long walks, under hedges, and pasture-fields, and mown
meadows where cattle graze, are her delight, especially if there are
trees interspersed; because in such spots insects most abound. When a
fly is taken a smart snap from her bill is heard, resembling the noise at
the shutting of a watch-case: but the motion of the mandibles is too
quick for the eye.
The swallow, probably the male bird, is the _excubitor_ to house-martins,
and other little birds, announcing the approach of birds of prey. For as
soon as a hawk appears, with a shrill alarming note he calls all the
swallows and martins about him; who pursue in a body, and buffet and
strike their enemy till they have driven him from the village, darting
down from above on his back, and rising in a perpendicular line in
perfect security. This bird also will sound the alarm, and strike at
cats when they climb on the roofs of houses, or otherwise approach the
nests. Each species of hirundo drinks as it flies along, sipping the
surface of the water; but the swallow alone, in general, washes on the
wing, by dropping into a pool for many times together: in very hot
weather house-martins and bank-martins dip and wash a little.
The swallow is a delicate songster, and in soft sunny weather sings both
perching and flying: on trees in a kind of concert, and on chimney tops:
is also a bold flyer, ranging to distant downs and commons even in windy
weather, which the other species seem much to dislike; nay, even
frequenting exposed seaport towns, and making little excursions over the
salt water. Horsemen on wide downs are often closely attended by a
little party of swallows for miles together, which plays before and
behind them, sweeping around them, and collecting all the sculking
insects that are roused by the trampling of the horses' feet: when the
wind blows hard, without this expedient, they are often forced to settle
to pick up their lurking prey.
This species feeds much on little _Coleoptera_, as well as on gnats and
flies; and often settles on dug ground, or paths, for gravels to grind
and digest its food. Before they depart, for some weeks, to a bird, they
forsake houses and chimneys, and roost in trees; and usually withdraw
about the beginning of October; though some few stragglers may appear on
at times till the first week in November.
Some few pairs haunt the new and open streets of London next the fields,
but do not enter, like the house-martin, the close and crowded parts of
the city.
Both male and female are distinguished from their congeners by the length
and forkedness of their tails. They are undoubtedly the most nimble of
all the species: and when the male pursues the female in amorous chase
they then go beyond their usual speed, and exert a rapidity almost too
quick for the eye to follow.
After this circumstantial detail of the life and discerning στοργὴ
of the swallow, I shall add, for your farther amusement, an anecdote or
two not much in favour of her sagacity:--
A certain swallow built for two years together on the handles of a pair
of garden-shears, that were stuck up against the boards in an out-house,
and therefore must have her nest spoiled whenever that implement was
wanted: and, what is stranger still, another bird of the same species
built its nest on the wings and body of an owl, that happened by accident
to hang dead and dry from the rafter of a barn. This owl, with the nest
on its wings, and with eggs in the nest, was brought as a curiosity
worthy the most elegant private museum in Great Britain. The owner,
struck with the oddity of the sight, furnished the bringer with a large
shell, or conch, desiring him to fix it just where the owl hung: the
person did as he was ordered, and the following year a pair, probably the
same pair, built their nest in the conch, and laid their eggs.
The owl and the conch make a strange grotesque appearance, and are not
the least curious specimens in that wonderful collection of art and
nature.
Thus is instinct in animals, taken the least out of its way, an
undistinguishing, limited faculty; and blind to every circumstance that
does not immediately respect self-preservation, or lead at once to the
propagation or support of their species.