310 SCOTT'S LAST EXPEDITION 
barrier berg. The tabular berg has a height up to 200 feet above 
sea and at times reaches the enormous length of 21 miles—truly 
a floating island. After partial melting it usually becomes 
slightly tilted to one side, or develops enormous caverns due to 
the action of the waves. In the final stages it may overturn or 
even disintegrate and after prolonged exposure to the elements 
is hardly distinguishable from the glacier berg. 
The general tendency of the currents in the Ross Sea is to 
carry these bergs northwards into the warmer water, so that in 
late summer the greatest accumulation of bergs occurs at a fairly 
low latitude. As a result also of their great heat capacity they 
are not associated at this time of the year with pack ice as they 
are in the early summer. 
That the number and distribution of these enormous reser- 
voirs of cold has a real effect upon the climate of Australasia can 
hardly be doubted, and it is therefore evident that a close study 
and analysis of the data on this subject may well give results of 
the very greatest value. 
a, 
