498 SCIENTIFIC RECORD FOR 1885. 



W. of Copenbagen) is the most celebrated of the Icelandic volcanoes. 

 It has been studied by Schythe and Kjerulf, It is located on a cliain 

 of 23,000 meters in length, rises in three or four terraces to a height of 

 1,556 meters, and is surrounded by large lava beds of 080 square kilo- 

 meters in extent. A little below the summit are craters which, in 1845, 

 were formed in a crevice running southwest to northeast. Parallel 

 with the Hecla emerge from the lava five ridges of soft gravel stone," 

 all running, partly disconnected, from southwest to northeast; in the 

 midst the Hecla rises on a base of 630 meters. The largest streams of 

 lava are found on the east slope of the Hecla, on which side the base 

 also is more elevated than on the west side. Several series of craters 

 appear around the Hecla, and at the foot of the chains of soft gravel 

 stone. At Torfajokull, to the east of the Hecla, the remarkable trachyte 

 lava current of Hrafntinnuhraun* is met with. The Hecla has hp,d 

 eighteen eruptions within historic times. 



The Randhukamhar (64° 12' N. Lat., 32° 25' Long. W. of Copenhagen) 

 is a volcano extending, like the Hecla, in a direction southwest to north- 

 east. Only one eruption (in 1343) is known to have occurred, whereby 

 a formerly very fertile valley became covered with ashes and pumice 

 stone. 



(3) Group of EeyJcjanes. — The peninsula of Eeykjanes should be con- 

 sidered a continuation of the Hecla. It is composed of stratified 

 masses; gravel, alternating with trap-rock, forming plateaus of about 

 125 meters in height, completely covered with lava, from which rise, in 

 a direction from southwest to northeast, a series of volcanoes and cones 

 of scoria, reaching to a height of 630 meters, containing several hot 

 springs and solfatares. Here, in X. Lat. 64° and W. Long. 33° 55', one 

 meets with the lava stream of Thurrdrhraun, dating from the year 1000. 

 It started from two craters situated in the northwest portion of the 

 Hellisheidhi and extended to a distance of 15 kilometers. In its south- 

 east portion, 4 kilometers long, it has an inclination of only 1° 50', but 

 it then descends with an inclination of 24° to 30°, and from a height 

 of 140 meters into the plain of Olfus. Nearly in the middle of the 

 peninsula, in 63° 50' K Lat. and 34° 14' Long. W. of Copenhagen, 

 there rises to the northwest of the solfiitare of Krisnvik the volcano 

 of Trolladyngja. The Icelandic annals mention six eruptions of the 

 TroUadyngja, which have been credited to the volcano of Odadha- 

 hraun of the same group, but which, according to the investigations of 

 Jonas Hallgrimsson, appear to be those of the Reykjanes. On the 

 southwest point of Reykjanes are several hot springs, and in the same 

 direction, about llj kilometers from the coast, a series of volcanic 

 islands, known under the name of Fugles Kjaer or Eldegar, in tlie 

 neighborhood of which several submarine eruptions have occurred. 



(4) Group of Katla. — Upon the grand glaciers of My rdalsjokull (1,320 

 square kilometers), separating the district of Skaptafell (Skaptafells- 



* Ilraim ilewignatea in Icelandic a current of lava. 



