ine
tendrils, the leaves and tops of the trees dried up immediately, and the
country was changed from spring to winter. The storm, although repeated
on the following days, passed away by degrees, and thus the floods,
which I strongly feared, did not occur. Almost always after great
eruptions of Vesuvius, storms of heavy rain have followed, and the
ground being covered with ashes, the water could not filtrate through
into the soil, but descended in muddy torrents over the adjacent
country, occasioning as much damage as the fire itself.

On the 30th, the detonations were very few, and the smoke issued only at
intervals, and by the 1st May the eruption was completely over.

When the smoke had cleared off the figure of the cone was seen to be
changed. (_Vide_ Plate 5a.)

The ground was perpetually disturbed whilst the Volcano raged, so that
the Observatory oscillated continually. Some shocks were felt not only
in the adjacent territory, but at a greater distance, at Montovi and
elsewhere. The oscillations at the Observatory were chiefly undulatory,
from N.E. to S.W. They were observed for some days after the termination
of the eruption, but not continuously, although they maintained some
intensity.

If we refer to January, 1871, we shall find that that eruption was
preceded by several earthquakes, among which were those of the months of
October, November and December, in the previous year, that wrought such
destruction in Calabria, and especially in the province of Cosenza; if
we consider that as only the last phase, we shall find that it was
preceded by great shocks of earthquake that devastated some regions of
Greece.[3]

The great quantity of lapilli which fell buried the scoriae with which
the Vesuvius cone was covered, so that it became somewhat more difficult
to ascend to the summit, and much less difficult to descend. Having
reached the top of the mountain, I found a large crater divided into two
parts by what seemed a cyclopean wall. The two abysses had vertical
sides, and revealed the internal structure of the cone. Their vertical
depth was 250 metres; and beyond that I observed a sort of tunnel
perforated in the rock, with a covering arch raised above the bottom of
the eastern abyss about 12 metres, judging by the eye. The interior
walls of the crater showed neither the usual stalactitic scoriae nor
sublimations, nor fumaroles, but alternate beds of scoriae and of compact
lava. The fumaroles and sublimations