universal catastrophe from which none could
escape."[257]

Had we discovered evidence that man had come into the earth at a period
as early as that when a large number of the fossil quadrupeds now
living, and almost all the recent species of land, freshwater, and
marine shells were in existence, we should have been compelled to
ascribe a much higher antiquity to our species, than even the boldest
speculations of the ethnologist require, for no small part of the great
physical revolution depicted on the map of Europe (Pl. 3), before
described, took place very gradually after the recent testacea abounded
almost to the exclusion of the extinct. Thus, for example, in the
deposits called the "northern drift," or the glacial formation of Europe
and North America, the fossil marine shells can easily be identified
with species either now inhabiting the neighboring sea, or living in the
seas of higher latitudes. Yet they exhibit no memorials of the human
race, or of articles fabricated by the hand of man. Some of the newest
of these strata passing by the name of "raised beaches," occur at
moderate elevations on the coast of England, Scotland, and Ireland.
Other examples are met with on a more extended scale in Scandinavia, as
at the height of 200 feet at Uddevalla in Sweden, and at twice that
elevation, near Christiana, in Norway, also at an altitude of 600 or 700
feet in places farther north. They consist of beds of sand and clay,
filling hollows in a district of granite and gneiss, and they must
closely resemble the accumulations of shelly matter now in progress at
the bottom of the Norwegian fiords. The rate at which the land is now
rising in Scandinavia, is far too irregular in different places to
afford a safe standard for estimating the minimum of time required for
the upheaval of the fundamental granite, and its marine shelly
covering, to the height of so many hundred feet; but according to the
greatest average, of five or six feet in a century, the period required
would be very considerable, and nearly the whole of it, as well as the
antecedent epoch of submergence, seems to have preceded the introduction
of man into these parts of the earth.

There are other post-tertiary formations of fluviatile origin, in the
centre of Europe, in which the absence of human remains is perhaps still
more striking, because, when formed, they must have been surrounded by
dry land. I allude to the silt or _loess_ of the basin of the Rhine