of a conversation which passed between two owls, reclaimed a
sultan, before delighting in conquest and devastation; but I would be
thought only to mean that many of the winged tribes have various sounds
and voices adapted to express their various passions, wants and feelings;
such as anger, fear, love, hatred, hunger and the like. All species are
not equally eloquent; some are copious and fluent as it were in their
utterance while others are confined to a few important sounds: no bird,
like the fish kind, is quite mute, though some are rather silent. The
language of birds is very ancient and, like other ancient modes of
speech, very elliptical; little is said, but much is meant and
understood.

The notes of the eagle-kind are shrill and piercing and about the season
of nidification much diversified, as I have been often assured by a
curious observer of Nature, who long resided at Gibraltar, where eagle
abound. The notes of our hawks much resemble those of the king of birds.
Owls have very expressive notes; they hoot in a fine vocal sound, much
resembling the _vox humana_, and reducible by a pitch-pipe to a musical
key. This note seems to express complacency and rivalry among the males;
they use also a quick call and a horrible scream: and can snore and hiss
when they mean to menace. Ravens, besides their loud croak, can exert a
deep and solemn note that makes the woods to echo; the amorous sound of a
crow is strange and ridiculous; rooks, in the breeding season, attempt
sometimes in the gaiety of their hearts to sing, but with no great
success; the parrot-kind have many modulations of voice, as appears by
their aptitude to learn human sounds; doves coo in an amorous and
mournful manner, and are emblems of despairing lovers; the woodpecker
sets up a sort of loud and hearty laugh; the fern-owl, or goat-sucker,
from the dusk till daybreak, serenades his mate with the clattering of
castanets. All the tuneful _passeres_ express their complacency by sweet
modulations and a variety of melody. The swallow, as has been observed
in a former letter, by a shrill alarm bespeaks the attention of the other
hirundines, and bids them be aware the hawk is at hand. Aquatic and
gregarious birds, especially the nocturnal, that shift their quarters in
the dark, are very noisy and loquacious; as cranes, wild-geese,
wild-ducks, and the like; their perpetual clamour prevents them from
dispersing and losing their companions.

In so ext