I 
4 ' 
160 Mr Menge's Account (^Jiis Mlnerahgical 
In my journey from south to north, I found a perpetual al- 
ternation of true volcanic and pseudo-volcanic rocks. The lat- 
ter are principally formed by Water^ or Aqueous Volcanoes. 
At the Huernafell, near to the Geyser, where there is also lava 
which has flowed, I found principally trap-porphyry. In a 
heap of debris brought down by the Bergwasser, I observed a 
number of masses which appeared like sandstone ; but I was 
inclined to deny the existence of sandstone here, as I had not 
met with any quartz rocks which could afford materials for this 
sandstone. I found this rock afterwards in Nordland, and ascer- 
tained it to be an ironshot trap-tuff *. The Blafell, beyond 
the Geyser, is of pseudo-volcanic formation. We found here, 
besides half-burnt basalt, also a quantity of porcelain-jasper, 
which originated from the ironshot trap-tufp. The trap-por- 
phyry is here again the predominating rock. On the Blafell, 
as well as on the Bald and Hoffsjokulls, the Neptunian destruc- 
tion is as dreadful as the volcanic lava of Kiolfell, which lies 
between the two latter. This destruction appears to have been 
occasioned by the glacier ice during the eruption of the Kiolfells 
and Baldjokulls. The whole country is so covered with ruins 
of rocks that it is with the greatest difficulty we can make our 
way through it. After passing these debris, we enter the valley 
of Suarta, and immediately into the lava-flood of the Kiolrhaun. 
Although every thing around us appeared solid and secure, we 
were often about to sink into rents of the lava filled with mud, 
which had been poured into them by snow and glacier-water. 
The lava of Kiolfell has the same kind of surface as that of the 
Guldbringe Syssel ; but it is more of the nature of melted basalt 
than of melted trap-porphyry. On the edge of the Kiolen- 
rhauns, is situated the district of hot-springs named Huera-vellir. 
We now travel through an extensive district of volcanic sand, in 
which I frequently found small pebbles of obsidian, and of com- 
pact basalt-lava, to the valley of Blanda, through which the road 
leads to the rocky shore of Malefell. The structure of the trap 
formation of Malefell, on both sides of the romantic Firth of 
Skaga, is very striking. All the members of the trap series are 
arranged above each other in horizontal beds. Some m.ay be 
* The same sjiccies of trap-tuff occurs near Kingliorn in Fifeshire. — Ed. 
