214 ELEMENTARY GEOLOGY 
the ice covering, the interior is completely hidden by 
an ice cap (Fig. 119). The rock of this land appears 
only at the margin, either at the very seashore or just 
inland from this, where mountains project above the 
ice sheet. 
Along the margin of Greenland, the glacier divides 
Fie. 119. 
The Bowdoin glacier, Greenland. A tongue of ice extending down a valley from 
the ice cap seen in the background. 
into tongues, sometimes surrounding mountain peaks, 
which are known to the Greenlanders as nunataks. In 
many places the ice enters the sea with solid front; but 
often it merely passes down the valleys in the form of 
tongues of ice, which have many characteristics of other 
valley glaciers. Excepting at the margins of these 
