them under new formations, thus exercising a long-
enduring influence on the surface of the country.

The whole North German plain shows traces of a
considerable movement of rocks to the southward.
Behind every upstanding pillar of basalt, on its southern
side, lies a space covered with scattered blocks, among
which mingle some derived from Scandinavia, Finland,
and the Baltic Islands, the proportion of these increas-
ing as we go northward. Geologists have recognised
that this change of place cannot have been effected by
icebergs floating upon the seas that overspread the plain,
but that the glaciers of the Scandinavian highland pushed
forward their masses of ice into Germany, and there
produced upon the land those effects which only glacier
masses can produce. The boulder clay, formed as
a ground moraine moving forward beneath a weight
of ice, is interspersed throughout with great and
little stones that have neither order nor stratification,
their surface being often characteristically polished and
scratched. Even blocks of immense size were carried
down by the slow stream of ice, which on the mountains
of Central Germany sometimes reached as high as 1500
or even 2000 feet. Its border followed the edge of these
mountains from Duisburg to the Moravian gap, and also
that of the Carpathians as far as Sambor. It also
penetrated far into the interior of the mountains near the
Thuringian Forest, as far as Gotha and Saalfeld, and
along the Elbe as far as Schandau, as well as deep into
secluded valleys of the Sudetic Mountains. The most
evident effect left upon the landscape by this great spread
of northern ice, is probably the complete levelling of
extensive tracts sheathed by the clay of the ground
moraines. The fruitful fields south of Breslau and north
of Leipzig were thus produced. But we shall seek in vain
along the southern limits of the northern diluvium for
typical terminal moraines. If they ever existed, they
have long ago been destroyed again. It is only in a more
northern portion of Germany that raised morainic
formations still persist in the scenery. This region

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