12 A rctic and A nt arctic Exploration [part i 
the enormous tabular icebergs which float northward in 
such vast numbers. Their height is about 200 ft., and 
their length from one or two to as much as twenty miles. 
Large floes are not very common, but there is a great 
deal of drifting ice, broken off from fixed land ice, which 
forms closely packed or sailing ice according to the winds. 
In December this pack ice is usually 300 miles across 
from 66° to 71 0 S. in front of the Ross Sea, but it lies 
further south in the King George IV Sea of Weddell. 
In February the Ross Sea is navigable, and the pack is 
scattered. 
