several months, was in a
state of great activity. At first, there were only volumes of smoke and
some small streams of lava, but these were followed by the most
magnificent projections of red hot stones and rocks rising 2,000 feet
above the top of the mountain. Many fell back again into the crater, but
a large portion were thrown in fiery showers down the sides of the cone.
At length, these beautiful eruptions of _lapilli_ ceased, and the lava
flowed more abundantly, though, being intermittent and always issuing
from the summit, it was quite harmless; volumes of smoke and vapour rose
from the crater, and were carried by the wind to a great distance. In
sunshine the contrast was beautiful, between the jet-black smoke and the
silvery-white clouds of vapour. At length, the mountain returned to
apparent tranquillity, though the violent detonations occasionally heard
gave warning that the calm might not last long. At last, one evening, in
November, 1868, when one of my daughters and I were observing the
mountain through a very good telescope, lent us by a friend, we
distinctly saw a new crater burst out at the foot of the cone in the
Atrio del Cavallo, and bursts of red-hot lapilli and red smoke pouring
forth in volumes. Early next morning we saw a great stream of lava
pouring down to the north of the Observatory, and a column of black
smoke issuing from the new craters, because there were two, and assuming
the well-known appearance of a pine-tree. The trees on the northern edge
of the lava were already on fire. The stream of lava very soon reached
the plain, where it overwhelmed fields, vineyards, and houses. It was
more than a mile in width and thirty feet deep. My daughters went up the
mountain the evening after the new craters were formed; as for me, I
could not risk the fatigue of such an excursion, but I saw it admirably
from our own windows. During this year the volcanic forces in the
interior of the earth were in unusual activity, for a series of
earthquakes shook the west coast of South America for more than 2,500
miles, by which many thousands of the inhabitants perished, and many
more were rendered homeless. Slight shocks were felt in many parts of
Europe, and even in England. Vesuvius was our safety-valve. The pressure
must have been very great which opened two new craters in the Atrio del
Cavallo and forced out such a mass of matter. There is no evidence that
water had been concerned in the late eruption of Vesuvi