THE SUNKEN ISLAND OF ATLANTIS. 23 
rents which, lite our great Gulf-stream, conducted warm water from the 
Indian Ocean to the Pannonic Bay, and to the hills about Vienna, 
could flow no longer. A great continent in the east placed Europe in 
direct connection with Asia. All this, and the partial sinking of 
Atlantis, must have seriously affected the Condition of Europe. True, 
the cooling-down process was gradual, hut nevertheless so marked that 
the accumulation of snow on the heights of the hills — now grown into 
mountains — by degrees assumed such an extent, that the whole coun- 
try, at least northwards of our central mountain-chainj became one im- 
mense glacier. Thus was ushered in the glacier period, Avhich also 
must have lasted a considerable time, till the climate, in consequence 
of favourable geological changes, began to improve. The open polar 
way to the Arctic seas was closed, and by the desiccation of the North 
African sea an oven was created in the desert of Sahara, which con- 
stantly supplied Europe with heated air. The British islands came in 
closer connection wath the continent, but Atlantis sank below the level 
of the ocean, leaving a few traces only behind. Europe as well as 
America thus obtained nearly their present shape. This w^as the time 
of the cave bears (ITrsus spel<Bus), the aurochs {Bos primigenius, Boj.), 
of the last European elephant and rhinoceros (Elephas antiqtmSy Palk., 
and Rhinoceros leptorJiinus^ Cuv.), and in North America of the Mis- 
sourium {Missourium theristocaulodon^ Koch). In Europe these great 
changes in the climate were followed by the introduction of an entirely 
foreign vegetation, not derived, as formerly, from the west, but from the 
east, passing from the Kussian steppes by way of the Caucasus and 
Crimea to Europe, where it took possession of the plains covered with 
gravel and mud. The time necessary for this eastern influx of plants 
and animals we may conjecture, but we liave no safe date of the com- 
mencement or duration of this period. Nor are we able to prove posi- 
tively whether at that time man already existed, though we have suc- 
ceeded in finding bones of hiai with those of animals of that period, 
and in North America a gigantic Missourium slain by stone weapons. 
The earlv historv of man is still wrapt in obscurity. It is therefore 
the more surprising to meet with a tradition of the highest importance 
with respect to that geological period, and containing as it were a con- 
firmation of the former connection of Europe with America, though we 
should have thought that this connection had ceased long before man's 
appearance on earth. This curious tradition is found in Plato's dialogue 
