ed. It is dotted with cones 60 or 70 feet
high, and extensively intersected by deep cracks, from both of which
sulphurous smoke ascends. It is surrounded by a wall about twelve
miles in circumference, in most parts 1000 feet deep. I despair of
conveying an idea of what our sensations were, when we first launched
out on this fearful pit to cross to the active crater at the further
end. With all the feeling of insecurity that attends treading on
unsafe ice, was combined the utter sense of helplessness the
desolation of the scene encouraged: it produced a sort of instinctive
dread, such as brutes might be supposed to feel in such situations.
This, however, soon left us, and attending our guides, who led us away
to the right for about a mile, we turned abruptly to the left, and
came upon a deep dike, which, running concentric with the sides,
terminates near the active crater, with which I conceive its bottom is
on a level. The lava had slipped into it where we crossed, and the
loose blocks were difficult to scramble over. In the lowest part where
these had not fallen, the fire appeared immediately beneath the
surface. The guides here evinced great caution, trying with their
poles before venturing their weight; the heat was intense, and made us
glad to find ourselves again on _terra firma_, if that expression may
be allowed where the walking was exceedingly disagreeable, owing to
the hollowness of the lava, formed in great bubbles, that continually
broke and let us in up to our knees. This dike has probably been
formed by the drainage of the volcano by a lateral vent, as the part
of the crater which it confines has sunk lower than that outside it,
and the contraction caused by loss of heat may well account for its
width, which varies from one to three hundred yards. In support of
this opinion, I may mention, that in 1840 a molten river broke out,
eight miles to the eastward, and, in some places six miles broad,
rolled down to the sea, where it materially altered the line of coast.
From where we crossed, there is a gradual rise until within 200 yards
of the volcano, when the surface dips to its margin. Owing to this we
came suddenly in view of it, and, lost in amazement, walked silently
on to the brink. To the party who had made the excursion the previous
evening, the surprise was not so great as to the others; moreover, a
bright noonday sun, and a floating mirage which made it difficult to
discern the real from the deceptive,