302 ComMuoiications reftpecting Bocks of Scandinavia. 



becomes crystalline and dull, presents an example of a change 

 of structure without any alteration of its solidity ; and copper 

 coins, buried in the earth, become oxidised without losing 

 their impressions. 



From the Tyri-Fjord, out of which the Draramen-Elv or 

 river discharges itself into the sea, we observe, to the south- 

 east, a long wall of rock, which box'ders the beautiful district 

 of Ringrige. In the bottom of the valley is transition 

 rock, with its petrifactions or fossils ; and above it there lies, 

 almost horizontally, the red non-fossiliferous sandstone, which 

 we consider as analogous to the old red. We now advance 

 on the Krokskleven by that steep wall, and we are not a little 

 surprised to see, lying in the middle of the declivity of the 

 sandstone, the most beautiful porphyry, with large crystals 

 of feldspath : it is Buch's rhombic-porphyry. That this por- 

 phyry is spread over the sandstone cannot be doubted, for it 

 is quite horizontal, and the bounding surface of these two 

 different rocks does not lie concealed under rubbish, but is 

 visible along the rocky wall, and so plain, that no profile 

 could delineate it better. One can place his hand upon it, 

 and the evidence of the senses must be believed. The marls 

 of the sandstone get white spots next the boundary, and fre- 

 quently become amygdaloidal. I here called to remembrance 

 the road from Castelruth up to the Seisseralp ; for if one 

 looks, for instance, in Euch's profile of that part of Tyrol, at 

 the front side alone, and leaves out the portion which repre- 

 sents the interior of the Seisseralp (which also has never 

 been observed), — as you state in your lectures, — then we 

 have a phenomenon analogous to the Krokskleven, viz., Me- 

 laphyr, lying above marl and limestone. As everything in 

 Norway bears a grand character, so also here this overlying 

 of the porphyry upon the sandstone is not confined to a single 

 locality, but, for the distance of many miles, we see in the 

 mountains the porphyry covering tlie sandstone. But nobody 

 has j^et observed anything like veins passing out of the por- 

 phyry into the sandstone below ; and as the porphyry is, in 

 this case, entirely cut off from the lower regions, so, in like 

 manner, is any explanation of this phenomenon, by the Vul- 

 canic theory, cut off. 

 The Slosberg in Hadeland, as Keilhau has already described 



