from below to above the Ice. 59 



ice is weak, the boulders break through it ; but when the ice 

 becomes (say 2 or 3 feet) thick, it freezes firmly to the boulder, 

 and when the tide rises, is strong enough to lift the boulder 

 with it. Thus, once fastened to the ice, the stone continues 

 to rise and fall with the rise and fall of each tide, until, as the 

 winter advances, it becomes completely enclosed in the ice, 

 which by measurement I found to attain a thickness of more 

 than 8 feet. 



Small stones, gravel, sand, and shells may be fixed in the 

 ice in the same way. 



In the spring, by the double effect of thaw and evaporation, 

 the upper surface of the ice, to the extent of 3 feet or more, is 

 removed, and thus the boulders, which in autumn were lying 

 at the bottom of the sea, are now on the ice, while it is still 

 strong and thick enough to travel with its load, before favour- 

 able winds and currents to a great distance. 



The finding small stones and gravel on ice out to sea does not 

 always prove that such ice has been near the shore at some time 

 or other. 



I have noticed that wherever the Walrus in any numbers 

 have been for some time lying either on ice or rocks, a not 

 inconsiderable quantity of gravel has been deposited, apparently 

 a portion of the excreta of that animal, having probably been 

 taken up from the bottom of the sea and swallowed along with 

 their food. 



Mammoth-remains. The position in which their Skeletons are 

 found, §*c. 



In LyelPs l Principles of Geology,' vol. i. p. 185, we read: — 

 " In the flat country near the mouth of the Yenesei river, 

 Siberia, between latitudes 70° and 75° north, many skeletons of 

 mammoths, retaining the hair and skin, have been found. The 

 heads of most of these are said to have been turned to the south ." 



As far as I can find, the distinguished geologist gives no 

 reason why the heads of the mammoths were turned to the 

 south ; nor does he say all that I think might be said of the 

 reasons why, and the means by which the skins have been pre- 

 served for such a long period of time. 



Having lived some years on the banks of two of the great 

 rivers of America, near to where they enter Hudson's Bay, and 

 also on the M'Kenzie, which flows into the Arctic Sea, I have 

 had opportunities of observing what takes place on these streams, 

 all of which have large alluvial deposits, forming flats and shal- 

 lows at their mouths. 



What I know to be of common occurrence in these rivers 

 may, if we reason by analogy, have taken place in ancient times 



