54 | The Sea 
If ice is only one year old it is called winter ice; if it is 
many years old it is called polar ice. Polar ice predominates in 
the polar sea as the name suggests. The thickness of this ice is 
on the average about 9 to 10 feet in the winter, although in 
certain mounds and ridges it reaches depths of 15 to 20 feet. 
STRIPS AND BELTS 
Floating ice fragments may arrange themselves into long 
strips or belts extending in parallel lines from horizon to 
horizon. By strips we mean narrow, thin lines of ice; by belts 
we mean lines many miles across. Strips are ordinarily formed 
at right angles to the direction of the wind; belts, parallel to 
the direction of the wind. 
ICEBERGS 
The real giants of the ocean ice are icebergs. They have 
different shapes. They may be flat-topped, with steep sides. 
Such ones are termed blocky. If they are triangular shaped, 
or dome shaped, pinnacled or with deep valleys, winged, 
horny, or twinned, they are classed as pyramidy. Icebergs 
usually appear a snowy white, but sometimes they are 
colored by bands of mud, pigmented marine life, or clear ice. 
Glacier born bergs often carry large quantities of rock debris, 
boulders, gravel, etc., thousands of miles out to sea and drop 
them into the ocean as they melt. 
Icebergs in the Antarctic Ocean attain enormous sizes, 
some being 20 miles wide, 70 miles long and with a vertical 
thickness of 2500 feet, 270 feet of which may be above water. 
Bergs of this size have been mistaken for islands—and no 
wonder! 
From a list compiled by Captain Lecky—that veritable old 
