THE EARTH. 21 



The mountain ice, as was said, is different in 

 every respect, being formed of fresh water, and 

 appearing hard and transparent ; it is generally 

 of a pale green colour, though some pieces are of 

 a beautiful sky blue ; many large masses, also, 

 appear grey, and some black* If examined more 

 nearly, they are found to be incorporated with 

 earth, stones, and brush-wood, washed from the 

 shore. On these also are sometimes found, not 

 only earth, but nests with bird's eggs, at several 

 hundred miles from land. The generality of 

 these, though almost totally fresh, have neverthe- 

 less a thick crust of salt water frozen upon them, 

 probably from the power that ice has sometimes 

 to produce ice. Such mountains as are here des- 

 cribed, are most usually seen at spring time, and 

 after a violent storm, driving out to sea, where 

 they at first terrify the mariner, and are soon 

 after dashed to pieces by the continual washing 

 of the waves, or driven into the warmer regions 

 of the south, there to be melted away. They 

 sometimes, however, strike back upon their native 

 shores, where they seem to take root at the feet 

 of the mountains ; and, as Martius tells us, are 

 sometimes higher than the mountains themselves. 

 Those seen by him were blue, full of clefts and 

 cavities made by the rain, and crowned with 

 snow, which alternately thawing and freezing 

 every year, augmented their size. These, com- 

 posed of materials more solid than that driving at 

 sea, presented a variety of agreeable figures to 

 the eye, which, with a little help from fancy, as- 

 sumed the appearance of trees in blossom ; the 



