es,
and should have come to some conclusions upon them in accordance with
the light they possessed. These terrible forces presented to the Greeks,
who clothed all the operations of Nature in poetic imagery and deified
her forces, their poetical and mystical side; and as there was a deity
for every natural force, so there was one for earthquakes and volcanoes.
Vulcan, the deformed son of Juno (whose name bears so strange a
resemblance to that of "the first artificer in iron" of the Bible, Tubal
Cain), is condemned to pass his days under Mount Etna, fabricating the
thunderbolts of Jove, and arms for the gods and great heroes of
antiquity.

The Pythagoreans appear to have held the doctrine of a central fire
(meson pyr) as the source of volcanic phenomena; and in the Dialogues of
Plato allusion is made to a subterranean reservoir of lava, which,
according to Simplicius, was in accordance with the doctrine of the
Pythagoreans which Plato was recounting.[1] Thucydides clearly describes
the effect of earthquakes upon coast-lines of the Grecian Archipelago,
similar to that which took place in the case of the earthquake of
Lisbon, the sea first retiring and afterwards inundating the shore.
Pliny supposed that it was by earthquake avulsion that islands were
naturally formed. Thus Sicily was torn from Italy, Cyprus from Syria,
Euboea from Boeotia, and the rest; but this view was previously
enunciated by Aristotle in his "Peri kosmou," where he states that
earthquakes have torn to pieces many parts of the earth, while lands
have been converted into sea, and that tracts once covered by the sea
have been converted into dry land.

But the most philosophical views regarding terrestrial phenomena are
those given by Ovid as having been held by Pythagoras (about B.C. 580).
In the _Metamorphoses_ his views regarding the interchange of land and
sea, the effects of running water in eroding valleys, the growth of
deltas, the effect of earthquakes in burying cities and diverting
streams from their sources, are remarkable anticipations of doctrines
now generally held.[2] But what most concerns us at present are his
views regarding the changes which have come over volcanic mountains. In
his day Vesuvius was dormant, but Etna was active; so his illustrations
are drawn from the latter mountain; and in this connection he observes
that volcanic vents shift their position. There was a time, he says,
when Etna was not a burning mountain, and the tim