Survey of Northeast Greenland. 449 
along the margin of the ice, flows through a series of marginal lakes, 
finally cuts through part of Storstrømmen, and debouches into the 
ice fjord of the latter (Borgfjorden). 
The quantity of water is considerable. Still, at the end of Au- 
gust 1912, we had some difficulty in finding a crossing for our horses. 
The marginal lakes in Dronning Louises Land. Where- 
ever we have reached as far as Dronning Louises Land, we have 
come across considerable marginal lakes or unmistakable traces of 
such. The marginal lakes at Ymers Nunatak, situated at an altitude 
of about 700 m above the level of the sea, have been exhaustively 
treated in “Die glaciol. Beob. d. Danmark-Expd.”, pp. 34—38 of the 
present volume. In March 1908 an immense marginal lake was 
found at Kap Bellevue, at an altitude of about 300 m; it then covered 
an area of 30 to 50 square kilometres (see Fig. 25 in “Die glaciol. 
Beob. d. Danmark-Exp.” and map in 1 : 500000, PI. Ш). During the 
winter 1912—13 we discovered, at the eastern edge of Dronning 
Louises Land, on about 76°40’ a marginal lake of 10 to 15 km in 
length, and only 30 metres above the level of the sea; also in the 
middle and western part of Dronning Louises Land did we meet 
marginal lakes, respectively of about 600 and 1200 m above the sea. 
It probably holds good of all of these marginal lakes that their 
water level varies greatly. The lakes are filled with inrushing melting 
water, up to the lowest pass altitude in the terrain surrounding them. 
In many cases the lowest pass altitude lies in the very marginal 
cleft, which the drainage is then made to follow as far as the 
next marginal lake, or until it makes its way. in under the ice; 
but now and then one also sees the drainage of the lakes taking 
place out across the inland ice. This is for instance the case with 
Jættebringen (the giants’ chest) on Ymers Nunatak and at the above- 
mentioned marginal lake on about 76°40’. Early or later — possibly 
at very long intervals — the marginal lakes further make an outlet 
for themselves from the bottom of the sea, in under the inland ice, 
and they may then become totally emptied, in so far as their bottom 
lies above the level of the sea. At Ymers Nunatak an emptying of 
this kind took place in the summer of 1907, in which manner the 
surface of the water had fallen about 50 m. The large marginal lake 
on about 76°40’ had, during the winter of 1912—13, by no means the 
extent which it had at a former higher water lewel, which was 
demonstrated by distinct terrace-formations. The outlet of the lake 
across the ice to the ice-fjord of Storstrømmen (Borgfjorden) consisted 
of an immense river bed, 15—20m deep and 50—80m wide. In 
1912—13 this river bed was inactive, at which time the surface of 
the lake lay considerably lower than the bottom of the river bed. 
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