GLACIAL DRIFT. 31/ 



bergs off the eastern coast, such as would be seen if the glaciers dis- 

 charged themselves as they do upon the western side. At the rate of 

 increase indicated by the observations of Hayes, the height of land may 

 be averaged at 5,000 feet, and the thickness of ice above it as 10,000 feet. 

 This flows mainly into Baffin's bay. Smith's sound, and the other waters 

 to the west. A northward transportation is indicated at Polaris bay, 

 where Dr. Bessel found numerous granitic rocks containing peculiar 

 garnets, such as abound in South Greenland, resting upon Silurian lime- 

 stones. On the western side are no less than thirteen well marked gla- 

 ciers discharging their bergs into the sea, as far north as Upernavik, 

 about 73° north latitude. The largest ones occur further north, some of 

 them being 3,000 feet thick. The bergs derived from them are of this 

 thickness, as measured by Hayes. The Humboldt glacier enters Smith's 

 sound with a width of 60 miles, the ice-cliffs, from 50 to 300 feet high, 

 extending 2,000 feet deep in some places. The adjacent rock-cliffs are 

 500 to 1,000 feet high. 



The derivation of icebergs from glaciers is well proved. The glacier 

 pushes down the fiords into the sea, till the buoyancy of the ice, lifted up 

 by the waters, causes it to separate in large blocks which float out to sea, 

 urged onwards by the land motion, and afterwards by the oceanic cur- 

 rents. Baffin's bay and Davis straits are filled with these bergs, which 

 float southerly till the warmer air and water of the lower latitudes dis- 

 solve them. It is uncommon to see them as far south as 40° north lati- 

 tude. The romantic history of Tyson's party illustrates the long con- 

 tinuance of floating ice. This party consisted of nineteen persons, and 

 they floated southwards 1,800 miles in six months' time, before they were 

 rescued, — October 16 to May i. 



These bergs often carry earth and rocks in immense amount. Scoresby 

 saw some carrying from 50 to 100,000 tons of material. Every Arctic 

 traveller describes them. This rubbish falls to the bottom as fast as the 

 bergs melt or topple over. It has been suggested that much of the 

 Great Banks of Newfoundland has been accumulated from the leavings 

 of icebergs. 



Greenland may be compared to a broad platter slightly inclined west- 

 erly, with occasional chinks in the sides through which the ice discharges 

 itself, as if it were a viscous body. We might say the ice accumulates 

 VOL. III. 41 



