50 LAUGE KOCH 



between the east and west coasts but remarkably far from the north 

 coast. 



The marginal zone of the inland ice cap is determined by (i) 

 the substratum, - and (2) the climatic conditions. The limit of 

 the marginal zone may, as a rule, be put at the 2,000-meter contour 

 (in extreme northern Greenland perhaps at the 1,500-meter contour) 

 Within this line of demarcation no melting takes place, and only 

 exceptionally do we find traces of inequalities in the foundation. 



Our knowledge of the inland ice cap is now so intimate that 

 we may, with fairly close approximation, predict the conditions the 

 traveler will meet with in the marginal zone. From north Green- 

 land especially three types are known : 



1. The littoral region consists of gneiss peaks which speedily 

 change into plateau-like tracts toward the interior. — The elevation 

 of the ice edge is about 1,500 meters, and the 2,000-meter contour 

 approaches the bordering land. In the months of July and August 

 a narrow melting zone is formed, too narrow to give rise to very 

 considerable streams. After a short journey we reach the 2,000- 

 meter contour and have now entered a level plain of dry and loose 

 snow. Examples are the west coast from 71° to 73° N. lat., and the 

 east coast from 7i°to 76° N. lat. 



2. The littoral region consists of fairly low gneiss tracts which 

 extend far into the interior and show a very irregular surface. — The 

 elevation of the ice edge above sea-level is, as a rule, low. The 

 surface is irregular with nunataks extending far into the ice. There 

 are irregular systems of fissures which prevent the forming of rivers 

 or lakes. The distance to dry firn snow is rather long. Examples 

 of this type are the west coast from Upernavik to Cape York, and 

 the east coast from Germania Land to Nordostrundingen. 



3. The littoral region is formed hy gneiss plains or fairly low 

 sedimentary plateaus. — The elevation of the ice edge above sea-level 

 is about 500 meters. The ice edge is smooth, free from cracks, 

 and easily traversed. Melting occurs in July, and at the close of 

 this month the thin layer of snow had melted about as far as up to 

 the 1,500-meter contour, above which there is dry and loose snow. 

 Near the ice edge there are many small rivers at right angles to it 

 and some few longer rivers and lakes. An example is furnished 



