230 Glacial Erosion in Norway. 
Dr. John Rae, who had very extensive arctic experiences, found 
that snow drifting over precipices into the sea resulted in the for- 
mation of bergs, sometimes a hundred feet thick, filled with the 
loose rock debris of the coast, and having the form of the shore 
where formed. Most of them break loose and drift away to melt 
or become stranded elsewhere. 
Greely describes the great momentum with which the floe-bergs 
come together. By their meeting the ice is crushed, and raised up 
into ridges fifty or sixty feet high. 
One cannot read carefully the results of the British Arctic Expe- 
dition of 1875-6 without being impressed with the erosive power 
of drifting ice, moving with a velocity never acquired by glaciers. 
Floe-bergs are pushed upon a shelving sea-bottom, until the ice 
has risen from twenty to sixty feet, after their first stranding in 
perhaps only from eight to twelve fathoms of water, although 
weighing tens of thousands of tons.? 
As the grounded floe-bergs are forced up the shelving sea-bot- 
- toms, ridges of earth and stones are pushed up in front of them. 
Floe-bergs which have been toppled over, thus showing their orig- 
inal bottoms, and also masses of pushed-up coast ice are found to 
be grooved and to contain angular stones with their exposed sur- 
faces scratched and polished. As the movement is greater than the 
velocity of glaciers flowing about obstacles, it is only natural to 
expect that the enclosed stones should be held firmly as graving 
tools, or be wrenched out owing to the brittleness of the ice under 
such great stress. 
In describing the ice action on the coast of Labrador, Professor 
H. Y. Hind says the “ pan-ice” (from five to twelve feet thick) is 
polishing the surfaces and sides of the rocky coast, and producing 
boulder clay. He says: “ When the pans are pressed on the coast 
by winds, they accommodate themselves to all the sinuosities of 
the shore line, and being pushed by the unfailing arctic current, 
which brings down a constant supply of floe ice, the pans rise over 
all the low lying parts of the Islands, grinding and polishing 
exposed shores, and rasping those that are steep-to. The pans are 
shoved over the flat surfaces of the Islands, and remove with irre- 
sistible force every obstacle which opposes their thrust, for the — 
1 In Canadian Journal, Toronto, 1859. 
2 British Arctic Expedition of 1875-76, Sir George Nares. 
