20 Dr. Torchhammer on the [July, 



Sandstone is the rock which is of all transition rocks most 

 abundant in the main ridge. The mountain Svuddu, which, 

 according to the measurement of Tillas, is 4422 feet high, 

 and, according to the measurement of Kissinger, 4693 feet, 

 is a conglomerate, which consists of the same materials as the 

 rest of the Scandinavian transition sandstone ; and Hausmann 

 has identified it with those of other parts of the Scandinavian 

 transition formation. The same author mentions an impression 

 on the surface of a piece of sandstone which he found in the inn 

 at Idre, where this sandstone is very frequent in the country 

 around. It seemed to belong to the stem of a fernlike plant, such 

 as are frequently found in the shale of the first coal formation. 

 This is the only instance where fossils are mentioned to occur in 

 in this sandstone ; some doubt may, therefore, be entertained, 

 whether it is not merely a lusus naturae. If it really was an im- 

 pression of a plant, it would be a direct proof that this sandstone 

 or quartz rock belongs to the transition formation ; while some 

 geologists are nevertheless of opinion, that it is a member of the 

 primitive class, principally because its position is frequently uncon- 

 formable with the gneiss upon which it rests. This, however, 

 does not prove much, because slate and limestone are, with few 

 exceptions, conformable with the sandstone, and they contain 

 numerous fossils. Besides, in some places not far from Christi- 

 ania, in Norway, sandstone occurs even upon slate and limestone. 

 Upon this san(5stone and conglomerate of the mountain Svuddu, 

 and a part of the main ridge m the neighbourhood, in the Swe- 

 dish province of Dalerne an extensive porphyry formation rests, 

 which furnishes the materials for the excellent works of art that 

 are made at Elfdale, now the private property of the King of 

 Sweden. The porphyry extends from the main ridge as far east 

 as Mora ; it is mostly of a red colour, the compact mass being 

 either siliceous slate or hornstone, or compact feldspar. The 

 sandstone passes distinctly into this porphyry. Breccia of bits 

 of porphyry cemented together by compact feldspar and syenite 

 likewise occur. The syenite is remarkable, as it furnishes a new 

 analogy between the formations of Dalerne and the country 

 round Christiania ; it occurs near Aasbye, and contains zircon, 

 which is so characteristic of the transition syenite of Norway. 

 The beds of sandstone, porphyry, and syenite, where a distinct 

 stratification may be observed are in general almost horizontal, 

 the angles never exceeding 20°. On the north side of the Lake 

 Siljan, a number of beds of limestone alternate with beds of 

 granite, both in a nearly vertical position, and in a direction 

 nearly north and south ; their elevation above the lake amounts 

 from 150 to 200 feet. On the south-east end of the lake, from 

 Ickaan to the church of Rattwick, much granite is found with 

 few and thin beds of limestone ; near the church of Rattwick, 

 a bed of limestone occurs, with grains of sand, and destitute of 



