282 



DEPTHS OF THE OCEAN 



on possible vortex movements. Four parallel sections were 

 made, the two in the middle by the " Michael Sars," the 

 southerly one being represented in Fig. 190, and the northerly 

 one in Fig. 191. In the map of the stations (Fig. 104, p. 122) the 

 position of the sections is seen, the distance between them being 

 20 to 25 nautical miles. Although the sections were so close 

 together they differed greatly. In the northern section the 

 lines are fairly regular; high salinities of more than 35.25 per 

 thousand are found only in the neighbourhood of Shetland, not in 



^00 



600 



600 



Fig. 191 



-The Northern Section in the Faroe-Shetland Channel 

 (nth- 14th August 1910). 



the middle of the channel. Vertical oscillations may have had 

 great influence on the appearance of the section. The two 

 sections might not have presented such great differences if the 

 observations had been taken at other times, but in any case they 

 point to other irregularities, in the first place to vortices with 

 vertical axes, similar to those known in rivers, only very much 

 larger. These vortices have rendered the motion of the water 

 highly complicated. The "Atlantic water" has moved towards 

 the north, having a breadth of 50 or 60 miles in the neighbourhood 

 of Shetland; between Stations 105 and 106 the water of the 

 upper layers has probably moved southwards, between Stations 

 106 and 107 to the north, and so on. Previous investigations 



