achievement within that region, or rather within those regions, of the
Old World where the stream-heads of our modern culture seem to take
their rise? The qualification which has slipped from my pen is half the
answer already, for we are to deal not with one homogeneous region but
with a cluster of regions in all climates from Arctic tundra to Sahara
and the Nile, and in all altitudes from alpine to maritime. Unity of
prehistoric culture, in such conditions, can at best be but a question
of degree.

Modern ethnology, emancipated from a belief in an immediate
consanguinity of mankind, by the spread of less infantile views about
Noah's Ark, goes on to question the sufficiency of language as a bond
of union, and forthwith stumbles over the Tower of Babel.

Two contemporary lines of discovery have tended to determine the result.
Geology gives us a very long margin of time since the north-west
quadrant began to be reinhabited by human beings after the Ice Age, and
assumed approximately its present distribution of land and water.
Archaeology, which in this aspect is the special stratigraphy of man,
sanctions an extension of time, since not merely human beings but
organized societies of men made their appearance in Europe, which far
exceeds the period required, or commonly assumed, for the spread of any
known Indo-European language, from any possible 'home' to any region
where it was spoken at the beginning of historic time. And not only does
archaeological evidence enable us to detect such societies sedentary for
a while on this or that site over the face of Europe and its
neighbourhood; it traces not merely one 'prehistoric culture', but a
number of distinct types of such culture, each with its own geographical
distribution, and with distributions which expand and contract at
different times, superseding one type of culture here, and another