362 Alf Trolle. 



0^. The presence of this warm layer, which is due to the warmth from 

 the atmosphere, shows, that the water has been fairly free of ice during 

 the period dealt with. At St. LXXVII, which, as already mentioned, 

 lay in the neighbourhood of the western edge of the polar pack-ice, 

 it is not found. 



It is a characteristic feature in the density curves, that there is 

 a break between 75 and 100 m., showing a sudden increase of den- 

 sity at this depth. This is most marked nearest the land (at St. 

 LXXIII) and gradually becomes less marked the further we come 

 from land (St. LXXV and LXXVI) until every trace of it is lost at 

 St. LXXVII, where the density curve courses quite evenly. This 

 break is due to the earlier described, special circulation, which was 

 at that time proceeding between the upper and lower layers; the upper 

 laj^ers tending away from land, the lower layers in towards land. 



This circulation thus reached out to the eastern part of the 

 coastal water. 



We see, that the coastal water is in reality in hydrographical 

 regards a region for itself, within which the water-layers circulate 

 independently, even though dependent on the Polar Current in that 

 its water-masses are gradually renewed from the western side of the 

 Current. 



Remarks on Section III. 



The section passes through the stations IV, VI, VII and IX from 

 1906 and LXXIII, LXXVII and LXXVIII from 1908. 



As already mentioned. Sect. I did not reach quite into the coast. 

 As it is of great interest, however, to follow the course of the isopykns 

 especially here, I have in place of the station wanting at ca. 76° N. 

 included St. LXXVII, which lies at ca. 78° N. L., and imagined it 

 to be at the position ca. 76° N. 17° W. in continuation of Sect. I. 

 In other words, I assume, that the hydrographical conditions at two 

 stations lying at ca. 76° N., 17° W. and 78° N., 15 1/4° W. will be 

 almost the same at the same time. I base the correctness of this as- 

 sumption on a comparison of observations from different stations 

 in the coastal water north of 75° N. L., which show, that the hydro- 

 graphical conditions there are dependent especially on the distance 

 of the station from land, but in very small degree on its geographical 

 latitude. 



Sect. II shows now, that the hydrographical conditions at St. 

 LXXVII, 78° N., 151/4° W. and at St. LXXVI, 771/2° N., 16° W., 

 were very much the same and it is thus permissible to conclude, that 

 a third station at ca. 76° N. L., taken at the same time and at the 

 same distance from land as the others, would have nearly the same 

 temperature and salinity. 



We may therefore imagine St. LXXVII moved S. S. W. past 

 St. LXXVI to meet the line from Sect. I, thus coming to lie at ca. 



