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did not see any of this cavernous lava, but from
a drawing of one of these hollow blocks, which
Dr. Bright was kind enough to show me since
my return, its blistered cavity, and confused or
imperfectly fused shell, would seem to indicate
that the feeble force of the igneous action of
the steam or gas had but just been sufficient to
heave it above the crust of the earth. This
supposition would appear to afford a better solution
of the difficult problem of accounting for
those blocks of lava that are perched on high
ridges, than that given by Sir George Mackenzie,
Avho imagines this lava to have flowed from the
loAver ground, and calls it the “ ascending lava.”
He says It is caused by the formation of a crust
on the coating of the surface, and a case or tube
being thus produced, the lava runs in the same
manner as water in a pipe.” This solution however
is, to me at least, quite incomprehensible.
The external air will unquestionably form a crust
on the surface of flowing lava, within which it may
he confined while in its descent; but would such a
crust be able to resist the pressure of a column of
melted lava in its upward ascent—if it could be
supposed that, inverting the order of Nature, the
lava should run up hill, before any “ pipe” could be
formed ? It is pretty clear that when the stream
once got to the bottom it might create itself into a
hill there, but would never run up one already
made.
I know not whether the lava that surrounds the
little harbour of Havnefiord be peculiar to Iceland,
bnt I have not found any description in other
volcanic countries to accord with the sc§ne of ruin
and desolation th a t here presents itself. The Icelanders
pretend to say it is th e ’most ancient-lava on
the whole island, but of this they can know nothing
but what their historical sagas inform them, and
Avhich carry back the real records of the country •/
at least to the beginning of the eleventh century.
This part of the island, from Hecla to the Snsefell
Yokul, was that however which received the first
brave emigrants who fled from the tyranny and
oppressions of Harold H arfag er; but it is not described
by them to have worn the same desolate,
the same dreary appearance, nor the same barren
aspect W'hich it now does.
After winding our oblique way for some little
Approach to Havnefiord.
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