ITS HISTORY AND INHABITANTS. 173 



the mountain rushed down in a violent torrent towards 

 the sea, bearing along with it so much of stones, sand and 

 detritus that a sheet of water having a depth of 180 feet 

 was changed into a diy sandy beach. Five fertile districts 

 were totally laid waste. Forty farms and two churches 

 were swept away out to sea with all that was in them in a 

 few hours. Pumice and ashes were carried into the north 

 and west of Iceland 200 to 300 miles. 



Its third or fourth eruption took place 1727, August 3rd, to 

 1728, May 25th, from five to six rifts in the glacier. The 

 people had to camp out and walked about with tubs on their 

 heads, as the air was filled with burning embers. 



The lava desert, OdaSahraun, which is 1,700 square miles 

 in extent, has many craters, mostly unexplored, except those 

 of the Dyngjufjoll, the largest volcano in Iceland, 4,500 feet 

 in height, east of the centre of the desert. These mountains 

 enclose a circular valley or crater Askja (the basket), 25 

 square miles in area, a vast crater, 17 miles inner, 24 outer 

 circumference, a mountain built up by innumerable lava flows 

 and upheavals to 3,800 feet, or 2,300 feet above Oda^ahraun. 

 Its bottom is 3,100 to 3,500 feet above sea level inclining 

 eastward (1° 26') towards the mouth of the valley which 

 opens into the surrounding lava tracts. Many active craters 

 stud its bottom. An eruption took place here in 1875. In 

 the south-east corner of this valley is a dip 800 feet deep in 

 the ground, in which there is a round hot lake having a 

 temperature of 72° F., and 4,000 feet in diameter Avhen it was 

 found in 1876. In 1884 it filled the whole dip and had become 

 10,000 feet long, but its temperature was only 56° F. 



On March 2yth, 1875, an eruption covered the whole of 

 eastern Iceland with pumice and ashes. The crater from 

 which the eruption proceeded is situated on the north-east 

 edge of the dip, 300 feet in diameter, 150 feet in depth. Its 

 exterior is a slope filled with ashes, its interior is round and 

 perpendicular. It is now a mud cauldron, which no longer 

 emits steam, but goes on boiling, in quaint colours, depositing 

 sulphur. Craters in this lake emit steam with thundering 

 noises, sounding in the far distance like the simultaneouf^ 

 letting off steam from innumerable pipes. Thoroddsen says : 

 " Nature is here grander and more overawing than in any 

 place in Iceland I have seen. He who once has stood on the 

 edge of this earthdip will never forget the sight." 



The steam pressure seems to have converted all the lava 

 in this eruption into pumice and ashes. 



