s the true end and aim of geological study. The
history of man seems to run back into a far distant and gloomy past.
Except for the poetical account in Genesis and the traditions of
various peoples throughout the world, real history fades away into an
earlier time of which there are no written records. When the delvers
in the Mesopotamian plain talk to us of kingdoms running back through
seven or eight or nine thousand years, we seem to be getting back to
the beginnings of things. But seven or eight or nine thousand years
are as nothing in comparison with the age of the earth, which runs
back into a past so limitless that no man can safely assign any set
figure to it. In a recent paper, Dr. Walcott, of the Smithsonian
Institution, says that the antiquity of the earth must be measured not
in millions, for they are too short, nor hundreds of millions, for
this carries us too far, but must surely be measured in tens of
millions of years.

When we attempt to study the past we find its various epochs unequally
clear to us. In human history only quite modern times are absolutely
clear. The history of the Middle Ages is distinct enough for us to
build for ourselves a picture of the time with reasonable hope of
gaining a correct view of the state of affairs. Back of this comes the
long stretch of the Dark Ages, in which here and there we have bright
spots, but it will perhaps long be impossible to portray clearly the
life of the people. Getting back to the Romans, things once more
become reasonably plain, as is true also in the case of Greek history.
Back of this stretches the Egyptian with fair precision, and, older
than it, the Babylonian and Chaldean. But these past three have not
left nearly so definite an account for us as did the later
civilizations of Greece and Rome.

When we try to go back of these we must change our method of study
entirely. Writing is absent, and all we know of earlier men must be
inferred from a few pictures that were daubed on the rocks or carved
in ivory or bone, from tools made of stone or bone, from a few metal
or stone ornaments, or from the bones of the men themselves. Even so,
the history fades out without telling us its own beginnings. It is
quite as impossible for history to write its origins as it is for man,
from his own knowledge, to describe his birth.

What is true of the human story is quite as true of that of the earth.
Recent steps are very plain. We may read them with considerab