SCIENTIFIC RESULTS 141 



or less representative of oceonographio coiulitions in the bay as they 

 noi-nially tend to i)revail. Tlie trouiihlike depression extended from 

 Disko Ishind northwesterly to the entrances of Jones Sound and Lan- 

 caster Sound, with the lowest i)oints centered in two pools, one about 

 100 miles east of Lancaster Sound Entrance and the other about the 

 same distance west of Disko Island. The highest elevation of the 

 sea surface was found in Smith Sound, where off Etah, Greenland, 

 it rose 26 dynamic centimeters above the lowest central areas of the 

 bay. The steepest slope, according to the calculations, was in the 

 lower end of the bay off Cape Dier where a gradient of 17 dynamic 

 centinu'tcrs in a distance of 30 miles Avas recorded. 



The slope currents on the Greenland side resulting from the 

 above described topography took form as a sluggish set moving north- 

 ward along the front of the principal iceberg fjords at the rate of 5 

 miles per day. This circulation provided for the immediate removal 

 of the bergs that had been carried out of the fjords into the open 

 coastal zone. The ice which remained inside the headlands, however, 

 was subject to another sort of behavior. 



About 1,000 bergs were observed by the Marlon expedition the 

 summer of 1928 distributed in Disko Bay. In whatever parts of 

 these waters the Marion cruised, 100 to 200 bergs were constantly in 

 sight from the ship but they appeared to be most numerous along the 

 southeastern shore of Disko Island and around the mouth of Jacobs- 

 havn Fjord. A particularly interesting sight was the row^ of bergs 

 always to be observed strewn along the southern shore of Disko 

 Island, where they appeared to ground temporarily, awaiting the 

 arrival of an unusually high tide or an offshore wind to start them 

 again on their westward journey out into the open sea. During the 

 Marioii's excursion of the Vaigat, the 6 to 10 mile wide strait which 

 separates Disko Island from the mainland, about 60 bergs were always 

 in sight from the ship at once, most of them in the vicinity of 

 Torsukatak Fjord, where they were noticeably drifting out of its 

 northern side. A comparison of the areas of greatest iceberg abun- 

 dance in Disko Bay with the current maps. Figures 91 and 92, shows 

 good agreement in the main with the southern, major, portion of the 

 bay as far as Claushavn dominated by an indraft from Davis Strait. 



The Marlon\s section across the Vaigat did not indicate such a 

 north w^esterly discharge but the GodthaaVs data, consisting of two 

 sections, one not far from Jacobshavn and the other at the outer end 

 of the Vaigat. both indicate it, and prove, therefore, that once the 

 bergs clear the coastal waters they will be set slowdy but definitely 

 northward. This statement is contrary to the belief of Mecking 

 (1906, p. 68), who stresses the importance of east winds to drive the 

 icebergs across Baffin Bay into the south-flowing current along the 

 American shore. While the bergs are still in the quiet fjords, off- 

 shore winds, no doubt, play a definite part in hastening the ice out to 

 sea. but once they have drifted away from the inshore w^aters they 

 will normally move northward. Lender a 5-knot-per-day gradient 

 current, moreover, the ordinary deep-drafted berg will be governed 

 chiefiv bv the current, even if a continuous easterly gale prevailed. 

 (Seep. i34.) 



The currents as drawn from the physical data collected by the 

 Godthaah expedition are further supported by the distribution of 

 thie icebergs in the waters north and west of Disko Island. Vessels 



