412 



APPENDIX V 



mille. They have also comparatively high temperatures; the 

 isotherm for 10° C. goes down to a depth of about 500 metres 

 in both these parts. 



It is obvious that both these comparatively salt and warm 

 volumes of water belong to the Gulf Stream. The more westerly 

 of them, at Stations 11 and 12, and in part 13, in the deep sea to 

 the west of the Porcupine Bank, is probably in motion towards the 

 north-east along the outside of this bank and then into Rockall 

 Channel — between Rockall Bank and the bank to the west of the 



Fig. 3. — Temperature and Salinity in the "Fram's" SotrrHERN 



Section, June, 1910. 



British Isles — where a corresponding volume of water, ^^•ith a 

 somewhat lower salinity, is found again in the section which was 

 taken a few weeks later by the Frith joj from Ireland to the west- 

 north-west across the Rockall Bank. This volume of water has 

 a special interest for us, since, as will be mentioned later, it forms 

 the main part of that arm of the GuK Stream which enters the 

 Norwegian Sea, but which is gradually cooled on its way and mixed 

 with fresher water, so that its salinity is constantly decreasing. 

 This fresher water is evidently derived in great measure directly 



