CRUISES OF THE "MICHAEL SARS " 123 



of valley, which is bounded on the west by the Rockall bank, 

 and on the east by the coast bank of Scotland. Farther north 

 this valley shallows towards the extensive ridge that stretches 

 from Iceland past the Faroe Islands to Shetland, and separates 

 the Atlantic Ocean from the Norwegian Sea at all depths 

 beyond 400 to 500 metres. The part of this ridge between the 

 Faroe Islands and Shetland is known as the Wyville Thomson 

 Ridge, which has frequently been examined, first by British, 

 afterwards by Danish, naturalists ; in fact, it may be regarded 

 as a classical field for oceanic research (see Chapter I.). The 



'tm 



■^^^iifeMfcwNi-^ 



Fig. 105.— Rockall. 



" Michael Sars " had made investigations there previously, both 

 on the Atlantic side south of the ridge and in the Norwegian 

 Sea to the north of it. In Fig. 104 our former research-stations 

 are marked with a cross. 



It was desirable, however, to re-investigate this area, em- 

 ploying there the same methods of working as we had adopted 

 in the North Atlantic, and we felt it necessary to have a 

 section south of the Wyville Thomson Ridge and another 

 one to the north of it. The valley between Britain on the one 

 side and Rockall and the Faroes on the other is really the only 

 connection between the two deep basins, for it is only through 



