226 ACCOUNT OF THE ARCTIC REGIONS. 



pcnsatcd by their amazing extent of surface. Some 

 of them have been observed extending many leagues 

 in length, and covering an area of several hundreds 

 of square miles ; each consisting of a single sheet of 

 ice, having its surface raised in general four or six 

 feet above the level of the water, and its base de- 

 pressed to the depth of ten to twenty feet beneath. 



The ice in general is designated by a variety of 

 appellations, distinguishing it according to the size 

 or shape of the pieces, their number or form of ag- 

 gregation, thickness, transparency, situation, &c. 



As the different denominations of ice will be fre- 

 quently referred to in the course of this work, it 

 may be useful to give definitions of the terms in use 

 among the whale-fishers, for distinguishing them. 



1. An icc-herg or ice-mountain, is a large insu- 

 lated peak of floating ice ; or a glacier, occvipying a 

 ravine or valley, generally opening towards the sea, 

 in an arctic country. 



2. Afield is a sheet of ice so extensive, that its 

 limits cannot be discerned from a ship's mast-head. 



3. A floe is similar to a field, but smaller ; inas- 

 much as its extent can be seen. This term, how- 

 ever, is seldom applied to pieces of ice of less dia- 

 meter than lialf a mile or a mile. 



4. Dnft-icc consists of pieces less than floes, of 

 various shapes and magnitudes. 



5. Brash-ice is still smaller than drift-ice, con- 



