NABiRATIVE. 105 



various terraces would mark the successive paroxysms or periods of reeleva- 

 tion Such a depression would not cause an irruption of the sea, since the 

 level of the lake is over six hundred feet higher than the sea-level. But 

 these phenomena are exceedingly complicated, and cannot be sufficiently 

 illustrated without further details. 



" The east and west direction of the scratches at Spar Island, contrary to 

 the general rule, I suppose to have been caused by the depth of the chan- 

 nel there, giving the glacier on its retreat a direction parallel to the shore of 

 the lake. We had there two very distinct systems of strias, one much more 

 southerly in direction than the other. Probably the glacier when advancing 

 from the north, having an enormous thickness, disregarded the shape of the 

 ground over which it passed, but on its retreat, that is, when it began to con- 

 tract, having meanwhile melted away considerably and thus become lighter, 

 its direction would be more easily modified. Similar phenomena are ob- 

 served in the present glaciers in Switzerland. In a little loch near Ben 

 Nevis there is also a secondary system of scratches, at right angles with the 

 general direction, which may be traced even on the bottom of the loch." 



We learned from the surveyors that a brown bear, differing from 

 the black and grizzly bears, is found in this region. It was said to 

 be about the size of the black bear, and is probably the barren-ground 

 bear, ( Ursus arctos americamis,') of Richardson, though he says this 

 species is not found so far south. 



On coming out of the tent we observed that standing by one of 

 the fires, so as to bring it between us and the rapids, the roar of the 

 water was suddenly shut off, as if by a door, the sound being inter- 

 rupted no doubt by the ascending column of heated air. 



The weather looked threatening this evening, and in the night we 

 had a violent shower accompanied by thunder and lightning. In the 

 midst of one of the gusts we were aAvakened by several small rivu- 

 lets playing down upon us from folds in the tent, which, on account 

 of the sandy soil, was not properly stretched. Indeed, without some 

 better contrivance than mere loops for the tent-pins, a tent like 

 that we had cannot be stretched so as to be water-proof in a vio- 

 lent shower. One of the tents, brought by Mr. Marcou, of the kind 

 used by the French officers in Algiers, was entirely water-proof, and 

 in every way more convenient than ours. It was square, with nearly 

 perpendicular sides, and stretched near the top by cross-pieces at 



