of the length of time it has taken the river to
fill up the lake as much as it has.

But in making this calculation the date arrived at was a maximum
one--that is, a point beyond which it is not reasonable to suppose the
time extended. These calculations gave as a result one hundred thousand
years. The meaning of this is that the time elapsed since the close of
the Glacial Age was something less than the number just stated. On the
other hand, a minimum date for this time has been obtained by estimating
the amount of erosion in the valley of the River Saone, in France.
From this we know that the time can not be less than seven thousand
years.<22>

It is, perhaps, doubtful whether we shall ever be able to obtain
satisfactory answers to these questions. From what we have repeatedly
seen of the slowness of development of primitive man, we do not doubt
but what the antiquity of Neolithic Man goes much farther back than
seven thousand years. When a naturalist finds in widely separated parts
of the world animals belonging to a common order, he is justified in
concluding that the order is a very ancient one. To illustrate,
the opossum belongs to an order of animals of which the only other
representatives are found in Australia and the neighboring islands.<23>
We are not surprised, therefore, to learn that this order was the
first to appear in geological time.<24> We think the rule is equally
applicable to races of men. We are told that the Turanian race, or, as
it is often named, the Mongoloid race, is a very widely scattered
one. Its representatives are found over the larger portion of Asia,
in Northern Europe, the islands of the Pacific; and they were the only
inhabitants of the New World at the time of the conquest.<25> This wide
dispersion would imply that they were one of the ancient races of the
world, and as such their antiquity must be far greater than the above
named number of years.

This point grows clearer when we see what light is afforded on this
subject by historical research. The Turanian people were in full
possession of Europe while yet the ancestors of the Hindoos and the
various European nations dwelt together as one people in Asia. As a
race they had grown old when the Celts commenced their wanderings. Egypt
comes before us as a powerful people, at a time at least as early as six
thousand years ago. Even at that time they had attained civilization.
But we need not doubt that there is a long seri