e southern flank in several streams finally reached the sea, making the
waters hiss and boil at the moment of contact. Slowly but surely these
relentless red-hot rivers of lava crept like serpents along the hill-side,
destroying vineyard and garden, cottage and chapel, on their downward
path. Resina shared the fate of its ancient forerunner Herculaneum, whilst
Torre del Greco and Portici suffered severely, as we can see to-day by
noting the great masses of lava flung on to the strand at various points.
To add to the universal confusion of Nature, the sea, which had now become
extraordinarily tempestuous, probably owing to some submarine
earthquake-shock, suddenly retreated half a mile from the coast, and then
as suddenly returned in a tidal wave more than a hundred feet beyond its
normal limits. Such were the main features of the second great eruption of
Vesuvius, wherein the ashes ejected by the Mountain were wafted by the
wind beyond the Adriatic, to the Greek islands and even to Constantinople
itself.

[Illustration: VESUVIUS AND THE BAY OF NAPLES]

From this date onward the Mountain became very active in contrast with its
previous condition of lethargy, and throughout the whole of the eighteenth
century there were frequent eruptions, many of them on a vast scale. All
these outbursts have been carefully recorded and commented upon, for
naturally the scientists of a great city like Naples were intensely
interested in the passing phases of their own volcano. During the latter
half of this century all the phenomena have been described for us by Sir
William Hamilton, British ambassador at the Court of the Two Sicilies, the
versatile diplomatist who eventually married the beautiful but frail Emma
Hart. During his long period of residence in Naples, Sir William made no
fewer than fifty-eight explorations of the crater alone, besides carefully
studying every peculiarity visible upon the sides of the Mountain. He was,
of course, a close observer of the great eruptions of 1766-7, and also of
the still greater convulsion of 1779, which, strangely enough, occurred on
the seventeenth centenary of the awakening of the Mountain from its
pre-historic slumbers. On this occasion, Hamilton, accompanied by a Mr
Bowdler of Bath, had the temerity to track the streams of flowing lava to
their hidden source by walking over the rough unyielding crust of stones
and earth that had formed upon the surface of the molten stream, as it
slowly t