70 THE WORLD'S LUMBER ROOM. 



would often be some difficulty in deciding which of the two 

 had been at work. 



Some of the creeks of South Australia, for instance, 

 which have perpendicular walls of tremendous height, bear 

 so strong a resemblance to the fjords of Norway and South 

 America, that, but for the absence of these tokens, one might 

 suppose them to have been excavated by the same workman. 

 The Australian fjords, however, are really canons, and are 

 due to the action of rivers and torrents, whereas the true 

 fjord has been carved by ice. 



The perpetual grinding of the glacier mill-stone against 

 the rocks which produces the "stone-meal," as it is called, 

 naturally deepens its bed year by year ; and in the course of 

 centuries, if the supply of snow continues, it will scoop out 

 deep channels with perpendicular cliffs. Then, if such a 

 change of climate should take place as has occurred many 

 times in the earth's history, the glacier will either melt away 

 altogether or shrink higher up among the mountains, and 

 its former bed will become a valley with, perhaps, a glacier 

 stream running at the bottom, and here and there some of 

 the rounded rocks, which, from their fancied resemblance to 

 sheep, the Swiss call " roches moutonmes" (Fig. 16). 



But if the glacier terminated on the coast instead of in- 

 land, something else might happen ; for if the land sank 

 a thing which has often taken place then, as the glacier 

 retreated, the sea would flow in and occupy its bed, and in- 

 stead of a valley there would be a fjord. The wonderful 

 series of fjords by which the coast of Norway is broken, and 

 those of Patagonia, British Columbia, Greenland, Kerguelen 

 Land, &c., have all been thus slowly engraved by glaciers. 



