sea-insects, he is sure to find his food in the spray of a heavy
wave; and you may see him flitting above the edge of the highest
surge. I believe that the reason of this migration of sea-gulls, and
other sea-birds, to the land, is their security of finding food; and
they may be observed, at this time, feeding greedily on the
earth-worms and larvae driven out of the ground by severe floods; and
the fish on which they prey in fine weather in the sea, leave the
surface, and go deeper in storms. The search after food, as we have
agreed on a former occasion, is the principal cause why animals
change their places. The different tribes of the wading birds always
migrate when rain is about to take place; and I remember once, in
Italy, having been long waiting, in the end of March, for the arrival
of the double snipe in the Campagna of Rome, a great flight appeared
on the 3rd of April, and the day after heavy rain set in, which
greatly interfered with my sport. The vulture, upon the same
principle, follows armies; and I have no doubt that the augury of the
ancients was a good deal founded upon the observation of the
instincts of birds. There are many superstitions of the vulgar owing
to the same source. For anglers, in spring, it is always unlucky to
see single magpies,--but _two_ may always be regarded as a favourable
omen; and the reason is, that in cold and stormy weather one magpie
alone leaves the nest in search of food, the other remaining sitting
upon the eggs or the young ones; but when two go out together, it is
only when the weather is warm and mild, and favourable for fishing.

_Poiet_. The singular connexions of causes and effects to which you
have just referred, makes superstition less to be wondered at,
particularly amongst the vulgar; and when two facts, naturally
unconnected, have been accidentally coincident, it is not singular
that this coincidence should have been observed and registered, and
that omens of the most absurd kind should be trusted in. In the west
of England, half a century ago, a particular hollow noise on the
sea-coast was referred to a spirit or goblin, called Bucca, and was
supposed to foretell a shipwreck. The philosopher knows that sound
travels much faster than currents in the air; and the sound always
foretold the approach of a very heavy storm, w