Icebergs upon Drift. 429 



tributed to the agency of icebergs by the advocates of the 

 aqueo-glacial theory, are, the transportation of earth and large 

 fragments of rock, the abrading and furrowing of the rocks, 

 the distortion and bending of strata of clay and sand, the 

 formation of bowl-shaped cavities by the rotatory movement 

 of the stranded berg, and the formation of accumulations, or 

 ridges of bowlders and gravel, like the moraines which border 

 the glaciers. We must reason from actual to ancient causes, 

 and, to ascertain the soundness of these views, must study the 

 phenomena of icebergs in our present seas. 



I will now proceed to present the facts which 1 have 

 collected. 



I. As to the mode of formation of icebergs, their original 

 position, and the manner in which they have been detached. 



II. The magnitude and form of those floating at sea. 



III. The direction, rate and nature of movement, the 

 limits of their transport, their grounding and dissolution. 



IV. Positive and negative testimony as to the transporta- 

 tion of fragments of rock, bowlders, mud, and earth. 



I. The islands of ice which are seen at sea, and receive 

 the name of icebergs, have been, without doubt, originally 

 detached from the glaciers of the north and south polar shores. 

 The term Iceberg was originally given to the glaciers of 

 Spitzbergen and Greenland, and is now applied by the South 

 Sea sealers and whalers to the glaciers of the South Shetlands, 

 South Georgia, Sandwich Land, and Terra del Fuego. Scores- 

 by, the most accurate writer upon the Arctic Seas, says that 

 the greater part of the icebergs that occur in Davis's Strait are 

 merely fragments of large glaciers which exist in great num- 

 bers on the coast forming the borders of Baffin's Bay. These 

 glaciers fill immense valleys, and extend, in some places, sev- 

 eral miles into the sea. In others, they form a precipitous 

 edge at the general line that forms the coast. 



In Greenland, according to Graab, the long narrow bays or 

 fiords, like broad rivers, run far up amid the lofty mountains 

 or table-lands of the interior. The vast plains of the interior 



