ot long after the
middle of the 19th century by the students of palaeontology and of
prehistoric archaeology. A recognition of the fact that primitive man
used implements of chipped flint, of polished stone, and of the softer
metals for successive ages, before he attained a degree of technical
skill and knowledge that would enable him to smelt iron, led the Danish
archaeologists to classify the stages of human progress under these
captions: the Rough Stone Age; the Age of Polished Stone; the Age of
Bronze; and the Age of Iron. These terms acquired almost universal
recognition, and they retain popularity as affording a very broad
outline of the story of human progress. It is obviously desirable,
however, to fill in the outlines of the story more in detail. To some
extent it has been possible to do so, largely through the efforts of
ethnologists who have studied the social conditions of existing races of
savages. A recognition of the principle that, broadly speaking, progress
has everywhere been achieved along the same lines and through the same
sequence of changes, makes it possible to interpret the past history of
the civilized races of to-day in the light of the present-day conditions
of other races that are still existing under social and political
conditions of a more primitive type. Such races as the Maoris and the
American Indians have furnished invaluable information to the student of
social evolution; and the knowledge thus gained has been extended and
fortified by the ever-expanding researches of the palaeontologist and
archaeologist.

Thus it has become possible to present with some confidence a picture
showing the successive stages of human development during the long dark
period when our prehistoric ancestor was advancing along the toilsome
and tortuous but on the whole always uprising path from lowest savagery
to the stage of relative enlightenment at which we find him at the
so-called "dawnings of history." That he was for long ages a savage
before he attained sufficient culture to be termed, in modern
phraseology, a barbarian, admits of no question. Equally little in doubt
is it that other long ages of barbarism preceded the final ascent to
civilization. The precise period of time covered by these successive
"Ages" is of course only conjectural; but something like one hundred
thousand years may perhaps be taken as a safe minimal estimate. At the
beginning of this long period, the most advanced race of men