1870.] BROWN—PHYSICS OF ARCTIC ICE. 679 
equivalent of the bergs) are detached, as the attraction of gravity 
overcomes the cohesiveness of the ice. These have been seen and 
described by Dr. Kane on many parts of the Arctic coast. I noticed 
them in the shape of “miniature glaciers between the cliffs”? (Trans. 
Bot. Soc. ix. 13) at Sakkak, lat. 70° 0’ 28” N., and on the Way- 
gatz shore of Disco Island. In this latter locality they were the 
overflow of the inland ice of the island. They are also seen in the 
little local glaciers, where the bed they move in is shallow, and 
the seaward or outward end high, as near Omenak, where, however, 
I did not see them, but depend for my information on intelligent 
Danish officers resident in that section. In Alpine regions away 
from the coast, the glacier, as it pushes its way down into warmer 
regions, either advances or retreats according to the heat of the 
summer ; but in either case it gives off no great masses of ice from 
its inferior extremity. The same is true of the Arctic glacier when 
it protrudes into some mossy valley without reaching the sea; but 
when it reaches the sea another force comes into operation. We 
have seen (1) the inland ice-field emptied by (2) the glacier; we 
now see the glacier relieving itself by means of (3) the iceberg or 
“ice mountain,” as the word means. 
3. The Iceberg.—When the glacier reaches the sea (fig. 1, e) it 
grooves its way along the bottom under the water for a considerable 
distance ; jindeed it might do so for a long way did not the buoyant 
action of the sea stop it. For instance, in one locality in South Green- 
land, in about 62°32! N. laf., between Fredrikshaab and Fiskernesset, 
or a little north of the Eskimo fishing-station of Avigait, and south 
of another village called Tekkisok, is a remarkable instance of this. 
Here the “ Tisblink,” or the “ice glance,” of the Danes (7. ¢. the 
projecting glacier—though English seamen use the word iceblink in 
a totally different sense, meaning thereby the “loom” of ice at a 
distance), projects bodily out to sea for more than a mile. The 
bottom appears to be so shallow that the sea has no effect in raising 
ij up; and the breadth of the glacier itself is so considerable as to 
form a stout breakwater to the force of the waves. It was long 
supposed that the iceberg broke off from the glacier by the mere 
force of gravity ; this is not so. It is forced off from the parent 
glacier by the buoyant action of the sea from beneath. The ice 
groans and creaks; then there is a crashing, then a roar like the 
discharge of a park of artillery; and with a monstrous regurgitation 
of waves, felt far from the scene of disturbance, the iceberg is 
launched into life. The breeze which blows out from the land, 
generally for several hours every day, seems, according to my ob- 
servation, to have the effect of blowing the bergs out to sea; and 
then they may be seen sailing majestically along in long lines out 
of the ice-fjords. Often, however, isolated bergs or groups of 
bergs will float away south or north. Bergs from the ice-streams 
of Baffin’s Bay will be found in the southern reaches of Davis 
Straits, while others, bearing débris which could only have been 
accumulated in South Greenland, will be found frozen in the floes 
of Melville Bay, or Lancaster Sound. It is a common mistake, 
VOL. XXVI.—PART I, 3D 
