

1818.] Henderson's Journal of a Residence in Iceland. 307 



they retract, but seldom so far as to recover their original situa- 

 tion, leaving- a face of rock or a waste of stones on which no soil 

 can ever after accumulate, and which, therefore, is lost to the 

 inhabitants. The following was the appearance of Breidamark 

 Ybkul when Dr. Henderson passed by it. 



" All along the margin, and a considerable way back, were deep indentations, 

 and, in s.ime places, chasms of an immense size, that penetrated further than the eye 

 could reach, and in which I could hear the distant dashing of the water as it fell 

 from the surface of the Yokul. The margin consisted, for the most part, of large 

 flat pieces of ice lying in all directions : sometimes it was as perpendicular as a 

 wall; at others, the ice lay horizontally, forming vast crysial grottoes; and, what 

 particularly struck me, was a number of small cavities and cells, in such parts of 

 the surface of the ice as were not exposed to the sun, which were filled with the 

 most beautiful pyramidic crystals, from a quarter of an inch, to an inch and a half 

 in diameter. In some places, the interior of the grottoes was completely studded 

 with these crystal groups, sparkling with a dazzling lustre, and assuming various 

 hues, according as they were more or less exposed to the light. 



" Towards the bottom of the slope, the ice has collected so much sand and clay, 

 that it assumes a black and dark grey colour : higher up, where the heat of the sua 

 has less influence, the winter snows remain undissolved, and give the Yokul a whiter 

 appearance; and, what is remarkable, at some distance from the margin, avast 

 number of round pillars, resembling sugar-loaves, only more pointed at the top, 

 begin to rise above the surface, and extend back to the regions of snow. They are 

 quite black in appearance, and may be from three to 20 feet in height. Where 

 the Yokul has pushed forward in one direction and again receded, large heaps of 

 clay, sand, and turf, are thrown up, so as to forma catenation of small bills round 

 its base; but whereits progress is continuing, no such hills are seen; only furrows 

 are laid .pen in the sand, by the sharp projecting pieces of ice, and the sand is 

 raised, precisely as the ground by a plough, to either side. In some places, I could 

 plainly observe the motion of the sand ; but whether it arose from the actual pro- 

 gress of the Yokul, or merely from thedissolution of the ice, I shall not determine." 



Occasionally the Ybkul volcanoes wake to activity, and then 

 the destructive effects of an ordinary volcano are combined and 

 heightened tenfold by the immense deluges of cold and of hot 

 water which are then produced. Four times during the last 

 century, namely in 1727, 1753, 1755 — 6, and 1783, has this part 

 of the island been thus desolated. With the following descrip- 

 tion of the last of these awful visitations, we shall conclude our 

 extracts from this interesting work. 



" About a month previous to the commencement of the eruption, a submarine 

 volcano burst forth at the distance of nearly 70 miles in a south-west direction from 

 Cape Reykianess in Guldbringe Syssel, and ejected such an immense quantity of 

 pumice, that the surface of the ocean wag covered with it to the distance of 150 

 miles, and the spring «hips considerably impeded in their course. 



" The Skaptar volcano, so called from the river of the same name, down which 

 the greater part of the lava was poured, is situated close to the eastern boundary 

 of West Skaftafell's Sys>el, about 32 British miles due north of Kjrkiubae Abbey, 

 and near the contiguous sources of the rivers Tftna, Skapta, and Hverfisfliot. It 

 lies principally in the valley called Varmirdal, and consists of about 20 red coni- 

 cal hills, '■tretching in nearly a direct line, from E.N.E. to W.S.W. which have 

 served as so many furnaces, from which the melted matter has been discharged iuto 

 the valley. From these craters the lava has flowed which inundated the low coun- 

 try, through the channel of the Skapta. What flowed down the Hverfisfliot, has 

 had its source in some other craters situated further to the north-east, but which are 

 evidently connected with the former hills, and would, in all probability, have 

 poured their contents down Varmardal, had it not been completely tilled with the 

 lava, which had already been emptied into it. 



" From the 1st to the 8th of June, 1783, the inhabitants of West Skaftafell's 

 Syssel were alarmed by repeated shocks of an earthquake, which, as they daily in- 

 creased in violence, left no reason to doubt that some dreadful volcanic explosion 



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