AMONG GLACIERS RECENT ANT) EXTINCT. 
171 
forest bed and the skeletons of its extinct mammalia. Seeds and 
berries of herbs, and shrubs too, must be often carried on ice-rafts 
out to sea ; and we may owe our Arctic plants which still linger 
on our mountain summits in Great Britain to such migrations in 
glacial times. Bears and wolves have often been seen and heard 
on icefloes, hundreds of miles from the shore ; and the crew of 
the Hansel are not the first men who voyaged upon a floe. 
I shall allude to Greenland again as revealing another history. 
It is the lot of few men to behold such ice and frost phenomena 
as I have alluded to. Ordinary mortals must be content with 
ascending mountain heights in more temperate latitudes, where 
the atmosphere becomes colder as we ascend ; for even in 
tropical regions there are mountain heights where frost does its 
work. In the Swiss Alps the snow line is about 8,500 feet 
above the sea, so that in the lofty recesses of the high Alps, 
which reach from 12,000 to 15,000 feet in height, the moment 
the sun goes down, frost sets in, even in the summer time, and 
the icicle droops from the rock, at night, where, in the daytime, 
dripped the runlet. In Switzerland, as is well known, we may 
ascend to regions on the summer snow-line, where comfortable 
hostels are established, and we may investigate snow and ice and 
glaciers. Such is the Inn of the Eiffel, above Zermatt and the 
great Gorner Glacier, and from near which we visit the Monte 
Eosa glaciers, and behold a panorama of snow mountains forty 
miles in diameter. Such snow mountains are the great feeders of 
the glaciers of the Alps. Everyone knows what a glacier is, and 
how they are rivers of ice, frozen masses, which descend some- 
times for a distance of twenty miles from Alpine heights to the 
valleys below. We need not enter into the disputed cause of 
their motion. I propose rather to direct attention to phenomena 
presented by these products of frost which come within the 
observation of all travellers in Alpine regions, and the observa- 
tion of which greatly enhances the enjoyment of Alpine travel. 
Unlike the continental ice of South Greenland, above which no 
rock rises above the ice to become shattered by the frost, or 
weathered by the gale, to send down its debris upon its glassy 
bosom, in Alpine districts the mountains rise sometimes 
thousands of feet above these rivers of ice, as they creep down 
the valleys and gorges ; and great masses of rocky debris fall on 
them, the result of the continuous and alternate action of thaw 
and frost. These accumulations are termed moraines : and 
there are lateral moraines, which are piled on the sides of a 
glacier ; medial moraines, which are formed when two streams 
of ice meet ; and the terminal moraine, where the debris is 
deposited at the termination of the ice. 
Now with regard to moraines , I advise every traveller among 
glaciers who would add to the enjoyment of his tour to learn 
