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Volcanic skies

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Volcanic skies

Posted by Sheridan Williams at 14:12 on 2010 May 31

In scanning the Journals I came across this in Volume 15 Number 7. It's highly relevant to the recent Icelandic volcano.Query No. 12 5.The Rev. Gilbert White in his "Natural History of Selborne," writes as follows regarding the summer of 1783 :"The summer of 1783 was an amazing and portentous one and full of horrible phenomena ; for, besides the alarming meteors and tremendous thunderstorms that affrighted and distressed the different counties of this kingdom, the peculiar haze or smoky fog, that prevailed for many weeks in this island and in every part of Europe and even beyond its limits, was a most extraordinary appearance, unlike anything known within the memory of man. By my journal, I find that I had noticed this strange occurrence from June 23 to July 20 inclusive, during which period the wind varied to every quarter without making any alteration in the air. The sun at noon looked as black as a clouded moon, and shed a rust-coloured ferruginous light on the ground and floors of rooms, but was particularly lurid and blood-coloured at rising and setting. . . . The country people began to look with a superstitious awe at the red lowering aspect of the sun ; and, "indeed, there was reason for the most enlightened person to be appre-"hensive, for all the while Calabria, and part of the Isle of Sicily, were "torn and convulsed with earthquakes ; and about that juncture, a volcano sprang out of the sea on the coast of Norway."Is there any other record of the peculiar appearance of the sun during that summer ? May sun-spots have had much to do with it ? Or would the volcano off the Norwegian coast entirely account for it ?John T. Bird.ReplyThe great eruption of Skaptar Jokul in Iceland occurred in 1783. Sir J. Herschel says, " Volcanic dust and a " preternatural smoke, which obscured the sun, covered all Europe as far as the Alps, over which it could not rise." The eruption began about May 10, 1783, which agrees with the dates given in the Query. Compare the " green sun " and the remarkable twilight glows after the Krakatoa eruption in 1883 (exactly a century later).A. C. D. Crommelin.