Jökull - 01.01.2001, Page 74

S. P. van Swinden
Perhaps it will be by no means useless to indi-
cate briefly the state of the air and the wind that pre-
ceded the haze. Thereupon from very warm days on
the 3 and 4 June on which the wind was E, NE,4 the
temperature of the air exhibited nothing remarkable.
From the 5
 –11
 the heat at one moment exceeded
the medium so to speak, at another moment was a lit-
tle below the medium. At the same time the column
of mercury in the torricellian tube was higher; yet the
mercury fell on the 9
 day. Between the 10
 –18
it stayed depressed,5 especially on the evening of the
15th and 16
 ; at this time the air was semi–clear.6
A little rain fell on days 4, 11, 13, 15, 17; but all
these days showed only 11 lines of water; day 4 alone
produced 6 and day 11 indeed roughly 3. Moreover
the winds were on the 5
 , SW, W; 6
 , NW, SW;
7
 , NW; 8
 , NNW; 9
 , NW; 10
 , NW, W; 11
 ,
SW, S; 12
 , NW; 13
 , SE, SW; 14
 , SW; 15
 , SE,
SW, NW; 16
 , SE, S, SE. And so they were variable,
and indeed so, such that I am undecided whether con-
sequently the conjectures I have drawn avail by rea-
son of the position from which by chance the haze
has been moved from one place to another among us.
Look indeed at the state of the atmosphere, when the
haze was present. It shows very great and medium
altitude of the thermometer, medium altitude of the
barometer and hygrometer, and regarding the state of
the air and the winds (see Table 1).
And so the winds almost always blew from NE
and NW, indeed especially from NW, while the haze
was present; the barometer reached the greatest alti-
tude, and rose most quickly, at the same time as the
haze appeared, as is evident on the 20
 day. The
warmest air, was the driest; moreover the 24
 was
the warmest and driest day of the whole month.7
On 1, 2, 3 July, the barometer remained at high
elevation, with the air semi–clear. The heat of day 2
was violent, when the thermometer rose to 26 ; the
wind blew from NE on day 1, except that at 7 a.m. it
was from NW. On day 2, it blew from NE, SE, NW,
NE and on day 3 it blew from W, SW, NW.
We implied already that this haze brought very
great damage. In the morning of 25 June the leaves
of many trees were discovered drooping; grass and
leguminous plants were drooping; the leaves fell as in
autumn and followed little later by a number of fruits.
The appearance of the fields was very sad. Dr. Brug-
mannusnus, a most acute botanist, allied to the fac-
ulty at Divion, dealt with this accurately and fully in
a book published in Belgium. Here I shall copy what
pertains to our scope. The author speaks of the city
Groningen, and the province of the same name. Be-
tween ( ) henceforth I8 add certain information.
“Now some days before the 24
 (at Franeker
thence from the 19
 ) first in the city, then in the coun-
try, a certain continuous haze was seen, but this ex-
cited no attention, since this phenomenon is not un-
usual here, nor did any irregular effects accompany
it. But some thought, that they had seen, as an imme-
diate consequence on the 21 
and 22

 certain mu-
tations in certain plants; but when that mutation did
not increase with the haze, I judged rather that this
was owed to a certain disease of these plants. I am
unable to decide whether any plant before the 24
had been affected in this way, which I shall mention
presently, and meanwhile the nature of the haze re-
mained always likewise. But on the 24
 day of the
month the haze, which was stronger than on the pre-
ceding day, brought with it a very distinct sulfurous
odor. This had been observed until now in the morn-
ing, but after noon on the 24
 it was much stronger,
such that it not only affected the sense of smell, but
even taste (this last, as far as I know, did not affect
Franeker). This sulfurous odor lasted the whole day,
but had diminished much on the following morning,

In the original text the directions are given as O, NO, but since van Swinden designates west with a W, then O most surely indicate the
Latin word “orient” which translates as east. Consequently, O and NO are taken to indicate east and northeast, respectively.
A cyclone (low pressure system) traveled SSW from Scandinavia to the British Isles at this time and then remained stationary over the
British Isles for several days (see Kington, 1988).
It is not obvious what Swinden means by semi-clear air, but most likely he is referring to partly cloudy skies.
An anticyclone was forming over Europe at the time and these weather conditions remained more or less unchanged for rest of June and
into July.
i.e., van Swinden.
74 JÖKULL No. 50