Vol. 52.] OF ABCTIC EUROPE AND ITS ISLANDS. 723 



From base to summit it is a homogeneous mass of blue clay, with 

 boulders and stones interspersed throughout. There is not a trace 

 of bedding throughout the mass. As I considered this deposit to 

 be a typical example of boulder-clay formed under water, I took 

 advantage of my journey in the neighbourhood last summer to 

 revisit the spot. A more careful examination showed that the 

 clay contains ice-scratched stones, and that mollusca are abundant 

 throughout the bed ; examples of Cyprina islandim and Pecteii 

 islandicus, partially retaining their colour, are common, likewise 

 stones to which the 'bases' of a Balanus are attached. On ascending 

 the terrace, which at its base is only a few feet above present high- 

 tide mark, and looking up the valley, one can realize that apart 

 from its composition it owes its formation to glacial causes. This 

 terrace is flat on the top and at the outer edge slopes seaward, and 

 the same on its opposite side looking up the valley. There can 

 be no doubt that this valley was formerly occupied by a glacier; 

 and when the land stood at a lower level than it does to-day, the 

 front of the glacier was in the sea and the terrace was formed by the 

 material which passed from under the ice, and is therefore a kind 

 of subaqueous moraine. 



As we sail from Tromso towards the North Cape, the course takes 

 us through Kaag Sund and past the island of Arno. The southern 

 shore of that island is fringed for miles by three great parallel 

 terraces. I roughly estimate Arno at about 1200 feet in altitude 

 and the terraces at 50, 100, and 150 feet above sea-level. Their 

 position on an island exposed to the full force of a stormy ocean is 

 entirely opposed to the possibility of ice-dams having had any 

 connexion with their construction. In Magero Sund, which separates 

 from the mainland the island whence juts out the North Cape, sea- 

 worn caves, much above the present sea-level, tell of recent elevation 

 of the land. 



The remarkable terraces in the Porsanger and other northern 

 fiords of Norway have been noticed by Bravais, Martens, J. D. 

 Forbes, Chambers, Campbell, Bonney, and others in their descrip- 

 tions of this part of Norway. The Porsanger is the first of the 

 large fiords that run into the mainland of Finmark. It is about 18 

 geographical miles in length. The hills on either side are low, 

 probably not more than 500 feet in altitude. They have an ice- 

 planed, ice-smoothed contour. The topographical contrast between 

 this area and the peaked Lofotens and those around and immedi- 

 ately south of Tromso is striking. The island of Stor Tamso 

 lies in the centre of the Porsanger Fiord. Its greatest height is 

 probably not more than 300 feet ; it is about 7 square miles 

 in extent. Evidently an ice-worn surface, it is entirely or almost 

 entirely covered with a growth of peat, showing a depth in places 

 of 8 or 9 feet before reaching the polished underlying rock, which 

 is a rather felspathic quartz-schist. 1 Where I landed, the rock, 

 smooth and slippery, passes with a gentle slope into the sea. 



1 See Prof. Bonncy's determination of thir< rook, p. 74J. 



