What can be the cause of it ?" "I don't know," replied Singleton, "it has long been a matter of dispute among learned men.

But we must examine it for ourselves, so come along." The remarkable colour of the snow referred to, although a matter of dispute at the period of the _Dolphin's_ visit to the Arctic Seas, is generally admitted now to be the result of a curious and extremely minute vegetable growth, which spreads not only over its surface, but penetrates into it sometimes to a depth of several feet.

The earlier navigators who discovered it, and first told the astonished world that the substance which they had been accustomed to associate with the idea of the purest and most radiant whiteness had been seen by them lying _red_ upon the ground, attributed the phenomenon to innumerable multitudes of minute creatures belonging to the order _Radiata_; but the discovery of red snow among the central Alps of Europe, and in the Pyrenees, and on the mountains of Norway, where _marine_ animalcula could not exist, effectually overturned this idea.

The colouring matter has now been ascertained to result from plants belonging to the order called _Algae_, which have a remarkable degree of vitality, and possess the power, to an amazing extent, of growing and spreading with rapidity even over such an ungenial soil as the Arctic snow.
While Singleton was examining the red snow, and vainly endeavouring to ascertain the nature of the minute specks of matter by which it was coloured, Fred continued to gaze with a look of increasing earnestness towards the tall column, around which a bank of fog was spreading, and partially concealing it from view.

At length he attracted the attention of his companion towards it.
"I say, I'm half inclined to believe that yon is no work of nature, but a monument set up to attract the attention of ships.