burrows during a frost.
Worms do not possess any sense of hearing. They took not the least
notice of the shrill notes from a metal whistle, which was repeatedly
sounded near them; nor did they of the deepest and loudest tones of a
bassoon. They were indifferent to shouts, if care was taken that the
breath did not strike them. When placed on a table close to the keys of
a piano, which was played as loudly as possible, they remained perfectly
quiet.
Although they are indifferent to undulations in the air audible by us,
they are extremely sensitive to vibrations in any solid object. When the
pots containing two worms which had remained quite indifferent to the
sound of the piano, were placed on this instrument, and the note C in the
bass clef was struck, both instantly retreated into their burrows. After
a time they emerged, and when G above the line in the treble clef was
struck they again retreated. Under similar circumstances on another
night one worm dashed into its burrow on a very high note being struck
only once, and the other worm when C in the treble clef was struck. On
these occasions the worms were not touching the sides of the pots, which
stood in saucers; so that the vibrations, before reaching their bodies,
had to pass from the sounding board of the piano, through the saucer, the
bottom of the pot and the damp, not very compact earth on which they lay
with their tails in their burrows. They often showed their sensitiveness
when the pot in which they lived, or the table on which the pot stood,
was accidentally and lightly struck; but they appeared less sensitive to
such jars than to the vibrations of the piano; and their sensitiveness to
jars varied much at different times.
It has often been said that if the ground is beaten or otherwise made to
tremble, worms believe that they are pursued by a mole and leave their
burrows. From one account that I have received, I have no doubt that
this is often the case; but a gentleman informs me that he lately saw
eight or ten worms leave their burrows and crawl about the grass on some
boggy land on which two men had just trampled while setting a trap; and
this occurred in a part of Ireland where there were no moles. I have
been assured by a Volunteer that he has often seen many large earth-worms
crawling quickly about the grass, a few minutes after his company had
fired a volley with blank cartridges. The Peewit (_Tringa vanellus_,
Linn.) seems to know instinctively that worms will emerge if the ground
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