X.] VOLCANIC ACTION. 199
Pliny also gives his adherence to the same view1. By more care-
ful observation of these occurrences it was further
established that the volcanoes served as a vent, by relieved by
means of which the frequency and violence of the °canoes*
earthquake movements were lessened. Thus Strabo, when speaking
of a succession of shocks by which the island of Euboea was
affected, remarks that they ceased when an eruption took place in
the Lelantian plain between Chalcis and Eretria*. And again, he
explains the cessation in South Italy of any such convulsions as
that which was supposed to have originated the Straits of Messina,
by the formation in that neighbourhood of cones of eruption like
those of the Lipari islands3. After Aristotle, the man of science
who contributed most to the study of this subject
was Posidonius. He described in considerable
detail, and in terms which closely correspond to
the records of modern observers of similar occurrences, the eleva-
tion of a new volcanic islet among the Lipari islands, which took
place during his lifetime. Strabo thus reports his narrative:—
"Posidonius says that within his memory, one day about the
summer solstice, just at dawn, the sea was seen to rise to an extra-
ordinary height between the islands of Hiera and Euonymus, and
continued to increase steadily for a certain time, until suddenly it
ceased. Those who ventured to sail near to the spot were appalled
by the sight of the dead fish that were carried by the current, and
by the heat and stench, and so took to flight; but one of the
vessels, which approached nearer than the others, lost part of its
crew, while the rest hardly escaped to Lipara, and from time to
time were attacked by delirium like epileptic patients, though at
intervals they recovered their senses. Several days afterwards the
surface of the sea was seen to be covered with mud, and at many
points jets of flame, with exhalations and smoke, burst forth, and
the scum subsequently hardened and assumed the appearance of
mill-stone4-" He is also quoted by Strabo in connexion with the
1 Pliny, 2. 192; ventos in causa esse non dubium reor...condito scilicet in
venas et cava ejus occulta flatn. neque aliud est in terra tremor quam in nube
tonitruum, nee hiatus aliud quam cum fulmen erumpit incluso spiritu luctante
et ad libertatem exire nitente.
* Strabo, z. 3. 16. 8 6. i* 6. 4 6. a. n.