HydrographicaJ Observations from the Danmark Expedition. 409 



drift-ice at ca. 12^9^. L. and drifted at that time due S. ^4 W. at 

 an average speed of 0.8 miles per hour, though the wind was S. W. 

 and thus opposed the drift southwards. From 10 — 11 Aug. 1906 the 

 vessel was again quite enclosed in the drift-ice at 15° — 16° W. L. and 

 drifted mainly S. W. at a somewhat less speed, namely on an average 

 0.4 miles per hour. The wind was N. N. E. and thus rather tended 

 to aid the drift southwards. 



Judging from the Table the directions of the current are very 

 irregular, but this irregularity is certainly in some part due to inexact- 

 ness in the reckoning during the days when the vessel was manoeuvred 

 forward in winding channels among the fields of drift-ice. In con- 

 sequence we can hardly conclude from these calculated directions of 

 the currents other than that the current at ca. 75° — 77° N. L. seems 

 to set most strongly southwards at 10^° — 16° W. L. and to be weaker 

 and more irregular to the east and west of this. The effects of the 

 tidal current were noticeable in the coastal water, the flood setting 

 toлvards north, the ebb to the south. Even in the drift-ice further 

 from land the influence of the tidal wave could be detected, changes 

 often occurring in the mutual positions of the ice-floes about the changing 

 of the tides. 



The south-going current of water over the Continental Shelf was 

 probably stronger in winter than in summer; it is difficult to find any 

 other explanation of some of the changes in the mouth of Oresund 

 in the course of the winter 1906—07 and 1907—08. 



In latitudes more southerly than those investigated by the "Dan- 

 mark", it seems as if the strong south-going current reached closer 

 in towards land; at 75° N. L. off Shannon Island there was a strong 

 movement in the drift-ice and large openings in it, whereas the ice 

 lay fast and immovable at ca. 76° — 77° N. L. off Koldewey Isl. The 

 reason for this must presumably be sought for in the fact, that the 

 current mainly folloлvs the Continental Shelf and that its eastern 

 edge comes nearest the coast off Shannon Island (see PL XII); the cross- 

 section of the current is thus reduced and it is then probable, that 

 the rapidity of flow is at the same time increased. 



It is quite natural, indeed, that there should be a close connection 

 between the ice and current conditions and that conclusions may be 

 drawTi with regard to the one from our knowledge of the other. Thus, 

 it can be seen from the chart of the ice boundary in the earlier men- 

 tioned work. Due d'Orléans, Croisière océanographique, that the 

 eastern ice-boundary runs nearly parallel with the coast-line later 

 discovered by the Danmark Expedition (and thus that, even before 

 the departure of the Danmark Expedition, from knowing the position 

 of this ice-boundary, one might have suspected, that the coast line 

 in N. E. Greenland north of 75° N. L. would have a direction east 

 of north). 



