And you will see that on the side of the Coiles towards Lochnagar, and between the knolls of them, are scattered streams, as it were, of great round boulder stones--which are not serpentine, but granite from the top of Lochnagar, five miles away.

And you will see that the knolls of serpentine rock, or at least their backs and shoulders towards Lochnagar, are all smoothed and polished till they are as round as the backs of sheep, "roches moutonnees," as the French call ice-polished rocks; and then, if you understand what that means, you will say, as I said, "I am perfectly certain that this great basin between me and Lochnagar, which is now 3000 feet deep of empty air was once filled up with ice to the height of the hills on which I stand--about 1700 feet high--and that that ice ran over into Glen Muick, between these pretty knolls, and covered the ground where Birk Hall now stands." And more:--When you see growing on those knolls of serpentine a few pretty little Alpine plants, which have no business down there so low, you will have a fair right to say, as I said, "The seeds of these plants were brought by the ice ages and ages since from off the mountain range of Lochnagar, and left here, nestling among the rocks, to found a fresh colony, far from their old mountain home." If I could take you with me up to Scotland,--take you, for instance, along the Tay, up the pass of Dunkeld, or up Strathmore towards Aberdeen, or up the Dee towards Braemar,--I could show you signs, which cannot be mistaken, of the time when Scotland was, just like Spitzbergen or like Greenland now, covered in one vast sheet of snow and ice from year's end to year's end; when glaciers were ploughing out its valleys, icebergs were breaking off the icy cliffs and floating out to sea; when not a bird, perhaps, was to be seen save sea-fowl, not a plant upon the rocks but a few lichens, and Alpine saxifrages, and such like--desolation and cold and lifeless everywhere.

That ice-time went on for ages and for ages; and yet it did not go on in vain.

Through it Madam How was ploughing down the mountains of Scotland to make all those rich farms which stretch from the north side of the Frith of Forth into Sutherlandshire.

I could show you everywhere the green banks and knolls of earth, which Scotch people call "kames" and "tomans"-- perhaps brought down by ancient glaciers, or dropped by ancient icebergs--now so smooth and green through summer and through winter, among the wild heath and the rough peat-moss, that the old Scots fancied, and I dare say Scotch children fancy still, fairies dwelt inside.