1 877.] The Great Ice Age and Origin of the “Till” 219 
plain beyond, while the moraines of the glaciers are but in- 
considerable and comparatively insignificant heaps of loose 
boulders, spread out on the present and former shores of the 
above-named glaciers, which are overflows from one side of 
the great neve, the Jostedal Sneefornd. AH of these glaciers 
flow down small lateral valleys, spread out, and disappear 
in the main valley, which has now no glacier of its own, 
though it was formerly glaciated throughout. 
What must have been the condition of this and the other 
great Scandinavian valleys when such was the case ? To 
answer this question rationally we must consider the meteor- 
ological conditions of that period. Either the climate must 
have been much colder or the amount of precipitation 
vastly greater than at present, in order to produce the gene- 
ral glaciation that rounded the mountains up to a height of 
some thousands of feet above the present sea-level. Probably 
both factors co-operated to effect this vast glaciation, the 
climate colder, and the snow-fall also greater. The whole 
of Scandinavia, or as much as then stood above the sea, 
must have been a neve or sneefornd on which the annual 
snow-fall exceeded the annual thaw. 
This is the case at present on the largest neve of Europe, 
the 500 square miles of the great plateau of the Jostedals 
and Nordfjords Sneefornd ; on all the overflowing neve 
or snow-fields of the Alps above the snow-line, over the 
greater part of Greenland, and (as the structure of the 
southern icebergs prove) everywhere within the great 
Antarctic ice barrier. 
What, then, must happen when the snow-line comes 
down, or nearly down, to the sea-level ? It is evident that 
the outthrust glaciers, the overflow down the valleys, can- 
not come to an end like the present Swiss and Scandinavian 
glaciers, by the direCt melting aCtion of the sun. They may 
be somewhat thinned from below by the heat of the earth, 
and that generated by their own friction on the rocks, but 
these must be quite inadequate to overcome the perpetual 
accumulation due to the snow-fall upon their own surface 
and the vast overflow from the great snow-fields above. 
They must go on and on, ever increasing, until they 
meet some new condition of climate or some other powerful 
agent of dissipation — something that can effectively melt 
them. 
This agent is very near at hand in the case of the Scan- 
dinavian valleys and those of Scotland. It is the sea. I 
think I may safely say that the valley glaciers of these 
countries during the great ice age must have reached the 
