i
and 105 feet in breadth. The direction
of the chafm itfelf is from north
to fouth : its weilern wall, from which
the other has been perpendicularly
divided, is X07 feet 6 inches in height,
and coniifts o f many ftrata (each of
which is about ten inches thick) of
lava, grown cold at different times, as
may eafily be difcovered by the apparent
cruft, that is full o f blifters of
a more dark brown, and not fo much
compreifed as the reft o f the mafs of
lava. The eaftern wall is only forty-
five feet four inches in height ; and
that part o f it which is direClly oppofite
to the higheft part on the other fide, is
no more than thirty-fix feet five inches
high.
It is likewife confidered as a fign of
an impending eruption, when fmall
lakes, rivulets, and ftreams dry up.
Some perfons believe, that it does not
contribute a little to hafteii the eruption,
when the mountain is fo covered
with ice, that the holes are ftopped up
through which the exhalations. Sec.
often found a free paifage.
Though
Thougli it is by no means my opinion
that this contributes much to it,
it cannot be denied, that the fire is
generally contained in thefe mountains
covered with ice, or, as they are called
in the country, jokuls.
The firft thing that is ufually obferved,
before a frefli eruption o f fire,
is the burfting o f the mafs o f ice with
a dreadful noife, whence it is called in
Icelandic Jokla-hloid (Jokul’s Sound)
and Jokla brejiar.
The flames then burft forth, and
lightning and balls o f fire iifue with the
fmoak, which arc feen feveral miles.
With the flames a number o f large and
lefs ftones are fometimes thrown to an
incredible diftance. I have feen a
round ftone near Nafverholt, about a
mile from Heckla, that was an ell in
diameter, and had been thrown there
in the laft eruption of Heckla. Eggert
Olafsen alfo relates, that at the laft
eruption of Kattlegiaa, a ftone which
weighed 290 pounds was thrown to the
diftance o f four miles.
A quantity o f white pumice-ftone
is alfo thrown up with the boiling waters
:
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