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pressure is behind the rivers of ice or glaciers, as they are called, forc- 

 ing them into the deep fiords or long narrow bays that are found 

 along the eastern and western coasts of Greenland. When the ice 

 reaches the water's edge, it is very thick and of large proportion. The 

 ice continues to work out into the water in the fiords. When the 

 upward pressure due to the buoyant force becomes sufficiently 

 great, the front end of the glacier is broken off. This break usually 

 comes at some deep fissure in the ice. The berg that is formed then 

 drifts out of the fiord, where it begins its journey propelled by the 

 currents encountered. 



There are, generally speaking, three currents, two cold water and 

 one warm water, that interest the ice patrol vessels. The cold cur- 

 rents, the Labrador and the East Greenland, have their origin in 

 the Arctic. They are the carriers of the iceberg menace from the 

 northward. The warm-water current, the Gulf Stream, has its 

 origin in the Gulf of Mexico. This is the current that is really 

 responsible for the disintegration of the menace and the melting of 

 the ice as it comes from the northward. 



The bergs which appear in the North Atlantic Ocean have their 

 origin almost exclusively from the fiords around Disco Bay in west- 

 ern Greenland and from Jacobshavn, Umanak, Upernivik, and 

 Godhab. 



The bergs from eastern Greenland usually drift down the east 

 coast and round Cape Farewell and then turn to the northward 

 along the west coast of Greenland. They usually disappear before 

 reaching latitude 64° N. When strong northerly and northeasterly 

 winds prevail in the eastern part of Davis Strait, some of the bergs 

 are driven westward, but it is believed that they usually disintegrate 

 in the comparatively warm water in the center of the strait and 

 never reach the Grand Banks. Some of the bergs from the east 

 coast it is believed find their way to the eastward of Flemish Cap. 



The following expressions and their meanings are submitted as of 

 interest. 



"Beset," a ship closely surrounded by ice. 



"Bore," to enter the ice under power and force the way through. 



"Bay ice," very thick young ice. 



"Brash," also called "trash," a collection of small pieces or frag- 

 ments of ice not frozen together. 



"Ice blink," a bright line on the horizon seen over an ice field and 

 denoting more ice. When a blue streak is seen on the horizon, it is 

 an indication of open water and is called ^'water sky." 



"Calving," a large piece of ice breaking off a parent berg and 

 falling into the water, or the breaking off of an iceberg from a glacier. 



"Field"^ — a field is a large collection of any kind of ice, usually 

 pans, adrift at sea and the extent not necessarily bounded by the 



