Jökull - 01.01.2001, Page 75

Observations on the dry fog in June 1783
and vanished entirely, although the haze remained un-
changed. From this time the haze, was now lighter,
now stronger, as on day 28; but then the sulfurous
odor was not perceived. The haze lasted until 1 July.
The sun was soon entirely obscured by the haze
and was soon enfeebled to such an extent, that one
could gaze at it without injury. But while the haze was
most strong, the border of the sun appeared colored.9
The haze perceivably increased the refraction of the
atmosphere/lower air on the 24
 day. The sun re-
mained above the horizon a little longer than usual.10
The haze was high enough that it affected the up-
per branches of the tallest trees; and it seemed to me,
as I was most credibly able to show from other cir-
cumstances, that it was again serene in the higher alti-
tude (see below, what I say about the things observed
of the city Neufchatel). The force, with which this
haze crawled through everything, which was exposed
to the atmosphere around us, is remarkable. It per-
vaded even into homes and bedchambers. Places com-
pletely shut, and which had no communication with
the atmosphere, were the only ones, into which the
sulfurous odor did not penetrate.
The barometer was very high while the haze was
present. Then from 20 June it rose greatly and was the
highest while the haze as strongest. When the haze
weakened the mercury descended. (N.B., the barome-
ter was one line, or one and a half and beyond, higher
at Groningen than at Franeker; at the most three lines
higher on the 25
 ; and only one on the 23   . Whence
it is agreed, that this difference was not particularly by
these instruments themselves, if indeed, it was in any
fashion caused by these instruments. On the 24
 the
difference was of 2 lines.)
The winds were
Day 17 SW,S,SE Day 21 W,NW Day 25 NE
Day 18 SW Day 22 W,NW Day 26 NE,N
Day 19 S,SE Day 23 NW,N Day 27 NWN
Day 20 SW,W Day 24 NE Day 28 NW
(It is clear thereupon, that the winds partly but
not entirely were similar to those that had position at
Franeker.)
In the afternoon of the 24
 many experienced
very troublesome headaches and respiratory difficul-
ties, similar to that which they experienced while
the atmosphere around us was filled with the vapor
of burned sulfur. Asthmatics experienced a return
of asthma. Horses, cows, sheep, felt no inconve-
nience. But this haze made a great slaughter of in-
sects, especially of fleas, which settle on leaves of
trees. When the leaves themselves were damaged,
the insects of the trees, which were not injured by the
haze, were killed exclusively as they remained intact
to the leaves. In the morning of the 25
 day the fields
showed a very sad appearance. The green color of
the trees and plants had disappeared and the earth was
covered with drooping leaves. One would easily have
believed that it was October or November. But hap-
pily it befell that not all plants were equally affected;11
certain uninjured ones remained standing (The cata-
log of Dr. Brugmannusnus showed four classes/types
of plants, that is to say, plants that were greatly dam-
aged, that were damaged less, a little, and not at all.)
In general it is possible to establish that it was not
the origin of fructification that was injured, but only
the leaves, which immediately began after midday on
the 24
 , but variously in various plants. Certain ones
were covered with spots, which increased gradually
and soon caused drooping of leaves. Some leaves
were not entirely spoilt; they continued to quicken,
but the places, in which they had been affected, were
soon made into little holes. Others faster than a
minute turned from green to brown, black, gray, or
white. Others kept their color, but began to droop, so,
that they were reduced to powder at the touch of one’s
fingers. A very great abundance of leaves fell. Certain
calyxes were injured, but in truth no flowers or fruit,
but because the leaves fell, that also caused the fruit
to fall, from failure of nutriment. Moreover the in-
jury, and falling of leaves, lasted for some time. These
things were continued up until 3 July, but the origin of

Implying that the outer edges of the sun were darker than normal? Referring to extended duration of the twilight or an illusion generated by refraction?
Similar observations are noted in several other contemporary descriptions of the haze (Thordarson, 1995). Obviously certain species of
trees are more vulnerable to volcanic pollution than others.
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