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Part III. — Seventh Annual llcport 



the Norwegian coasts, which had a uniformly lower specific gravity than 

 that found off the Scottish and English coasts. As Dr Meyer points out, 

 this marked lowering of the specific gravity of the surface waters along 

 the Norwegian coasts could not be attributed to the comparatively small 

 supply of fresh land water contributed by Norway itself, but was evidently 

 chiefly due to the outflow from the Baltic. 



In this connection the observations made during the ' Pommerania ' 

 Expedition as to the direction of currents at different depths are specially 

 interesting and important. As has been stated above, the southern area 

 of the North Sea was filled for the most part from surface to bottom with 

 warm Atlantic water, this warmer water being cut off from the colder 

 northern area by the Dogger Bank. 



The outflow from the southern area of this warmer water was traced as 

 a current which sets in along the coasts of Schleswig-Holstcin and Jutland, 

 in an easterly direction, that is to say, into the Skagerack, where it bent 

 round and followed the line of the Norwegian coast in a northerly direc- 

 tion. The outflow of fresh or brackish water from the Baltic follows the 

 same course out of the Skagerack, and was distinctly traced along the 

 Norwegian coast as a shallow surface current only about 4 fathoms deep 

 superposed on the heavier water flowing in the same direction and coming 

 from the southern area of the North Sea, and originally therefore from the 

 Atlantic. The temperature of the shallow surface current was found to 

 ' be markedly higher than that of the Salter water underneath. It must be 

 remembered that all the ' Pommerania' observations were made during 

 summer. During winter the temperature of the outflowing waters from 

 the Baltic is of course much lower. 



In one instance in which a perfectly satisfactory observation was made 

 of the direction of the flow of the waters in the Norwegian furrow or 

 channel, distinct indication was obtained of a thiixTcurrent flowing along 

 the bottom in an opposite direction to the two upper currents, that is to 

 say, along the line of the Norwegian coast towards the Skagerack. The 

 presence of this third and lower current was also rendered probable by 

 the low temperature of the lowor layer of water, separated by a thin 

 intermediate layer from the warmer waters above. 



The Cruise of H.M.S. ' Jackal ' in the North Sea during 

 September and the early part of October 1888. 



In consideration of the large area over which it was proposed to 

 extend observations, and of the necessity for completing these observations 

 within a comparatively short period, it was decided to limit the work to 

 bo undertaken during the expedition almost entirely to physical and 

 chemical investigations. To assist me in carrying out this, part of the 

 work, I was accompanied by Dr C. Hunter Stewart and Mr F. M. Gibson, 

 B.Sc. I have much pleasure in stating that to the able and constant 

 assistance of these gentlemen, the successful carrying out of a very great 

 part of the scientific work of the expedition is due. I have also much 

 pleasure in acknowledging the hearty and kindly manner in which the 

 officers and crew of the ' Jackal ' did everything in their power to further 

 the work of the expedition. I am especially indebted to Lieutenant 

 Farquhar, Commander, for the valuable advice and support which he gave 

 throughout the cruise, and to Lieutenant Dundas for the determination of 

 the exact times and places at which the various observations wore made. 

 Thomas Mortimore, chief petty officer, gave constant assistance throughout 

 the cruise, during which much extra work was undertaken by him. His 

 previous experience in similar observational work enabled him to render 

 very valuable service. 



