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