Jökull - 01.12.2003, Blaðsíða 6

Thorvaldur Thordarson
appeared to weigh around ten pounds or more.”
This may be the oldest known description of cow-
dung and spindle bombs. Moreover the passage em-
phasises that Steingrímsson looked upon volcanic
eruptions as a natural phenomenon and that he ob-
served the Laki event from a realistic point of view.
He also realised the importance of keeping records
on the course of events and the damage caused by
the eruption, in order to ease any proceedings with
the Danish authorities with regard to natural disas-
ter assistance. Although his writings contain a certain
overtone of religious superstition, he clearly discrim-
inates between observations and interpretations in his
descriptions.
CONSISTENCY OF THE ELDRIT WRITTEN
BY STEINGRÍMSSON
The first two Eldrit written by Steingrímsson in 1783
were documents accompanying letters to the authori-
ties (Rafnsson, 1984). They record the progress of the
eruption up to the cited dates (Table 1). The third Eld-
rit was regarded by Steingrímsson to be a complete
description of the eruption and was written so that the
public could become acquainted with this “chastise-
ment of the Lord for their reformation.”
Earlier publications regarding the Laki eruption,
i.e. the works by S. Hólm and M. Stephensen (Table
1) were not accessible to the Icelandic public, because
they were published in Danish and in Steingrímsson’s
opinion they were “incomplete and inconsistent.” In
light of this and the famine caused by the Laki event,
Steingrímsson felt it necessary to describe the details
of the eruption and its consequences, or as he stated
in his epilogue to Fullkomið skrif um Síðueld; “Here I
will compile in one document what I wrote down day
after day, season-after-season during the eruption, to
the day the good Lord relieved us of this burden. Ev-
erything written here is accordant with what other ve-
racious human beings and I saw and experienced dur-
ing the eruption, as my conscience and the Lord God
can verify. Nothing is overstated or exaggerated, but
minor incidents are left out, especially those which
concerned families and individuals because such de-
tails would be too redundant.”
In general the consistency of Steingrímsson’s
works is very good and the discrepancy that occurs
is mainly concerned with dates of specific events. In
most cases the difference is only one day and therefore
does not seriously affect the reconstruction of events.
If it is kept in mind that the two earlier works, Eldrit 1
and Eldrit 2 were written during the eruption, but his
latest Eldrit was completed five years later, this kind
of inconsistency could be expected. It is logical to as-
sume that dates and statements, where they differ, are
correct in the earlier works.
The first thing to consider is Steingrímsson’s de-
scription of the ash-fall during the first days of the
eruption. In the first Eldrit it is noted that footprints
could be made in the ash on the third day of the erup-
tion, i.e. 10 June. For footprints to mark in a tephra de-
posit it needs to be at least 0.1 cm thick (Thorarinsson,
1955). In Eldrit 2 and 3 this is said to have occurred on
the first day of the eruption. At the same time the de-
scriptions of the volcanic cloud become statelier (see
Thordarson et al., this issue). Another interesting ad-
dition in the two later Eldrit is Steingrímsson’s state-
ment that the plume was pushed back in the afternoon
on 8 June by a southerly sea breeze. This statement
seems to challenge the above-mentioned descriptions
of a statelier plume, because a light sea breeze would
hardly have a significant impact on the dispersal of an
expanding eruption column.
All of the Eldrit clearly show that the ash-falls dur-
ing the first days of the eruption were all of short du-
ration, lasting for few hours at the time, and were fre-
quently accompanied or followed by heavy rain. Ash-
fall occurred in the Síða and Fljótshverfi districts and
it is likely that some ash fell in the Landbrot district.
According to J. Eiríksson I (Table 1), no tephra fell
in the Skaftártunga district during this time and no re-
ports mention tephra fall in the Meðalland and Álfta-
ver districts (position of these districts are shown on
Figure 1 in Thordarson et al., this issue). Reconstruc-
tion of the tephra dispersal from thickness measure-
ments in soil profiles indicates that the Skaftártunga,
Meðalland and Álftaver districts were not severely af-
fected by tephra fall from the Laki eruption (Thordar-
son and Self, 1993).
If the eruption cloud was as large as Steingrímsson
indicates in Eldrit 2 and 3, the tephra would be ex-
4 JÖKULL No. 53, 2003