INTRODUCTION. 
Ixiii 
has elapsed, most of them join in the song. The imagination, perhaps, 
wanders into the regions of fiction when it pourtrays these first twitterings 
as lessons of prudence and caution from the old, as descriptions of the 
difficulties to be surmounted in the voyage, of the advantages of mi- 
gration, and of the dangers that await the unwary and impotent; and the 
general chorus, as the, answer of the young of their determination to 
observe and fulfil their duties. Although these opinions should be merely 
the wild flights of fancy, their actions evidently are the effect of cogitation 
and design. They often ascend, as if by some sudden impulse, in perfect 
unison, to vast heights in the atmosphere, and return by a circuitous course 
to their former situation. At length, a loud, chirping, simultaneous scream 
announces their departure, and, making an extensive sweep, they ascend 
beyond the reach of the eye by spiral convolutions. Similar movements 
are made by the second brood, which commonly takes its flight before the 
tenth, or, at the latest, the fifteenth of October. A few still remain, and 
some of them, unable to accompany their fellows not from want of incli- 
nation but of power, sink into a state of torpor and inaction, from a life 
of wonderful agility and violent exertion ; and, most probably, never 
become reanimated. But if we take the aggregate of those that have been 
thus discovered in a torpid state, they will bear no more comparison with 
the immense multitudes that annually migrate, than one does to thousands. 
Nay, if we add to them the numbers which have been seen some time 
after the flight of their fellows, the relative proportion will be but slightly 
increased ; and even this transitory appearance in a warm winter’s day 
may be attributed to a few weak individuals which were then preparing to 
migrate, or so impotent, that they could not quit their native land.^ At 
I have often seen a few Swallows and Martins in the latter end of October, several times in 
November, and twice in December : (among other instances, five Martins and three Swallows on 
the nineteenth of October ; three Martins the twentieth of the same month, and four Martins on 
the eighth of December, 1808; and on the fifth day of December, 1805, a fine sunny day, I 
discovered, in a warm sheltered situation, a flock, composed of thirty-two Martins, hawking in the 
air with all the agility of a summer’s flight, which were most probably either preparing for depar- 
