160 
THE NATURAL HISTORY 
[LETT. 
place during the interval ? for we cannot suppose they had 
migrated to warmer climes, and so returned again for one day. 
Is it not more probable that they are awakened from sleep, and 
like the bats are come forth to collect a little food ? Bats 
appear at all seasons through the autumn and spring months, 
when the thermometer is at 50°, because then 'plialoerim and 
moths are stirring. 
These swallows looked like young ones.] — Observations on 
Nature. 
Some few pairs haunt the new and open streets of London, 
next the fields, but do not enter, liiie 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 undoubt- 
edly 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 
. uTop^T] of the swallow, I shall add, for your further amusement, 
an anecdote or two not much in favour of their 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 wdth 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 col- 
lection of art and nature. 
