ic events necessarily involves an orderly and corresponding
progression of organic life.

'To this doctrine of the control of physical agencies over organic
forms I acknowledge no exceptions, not even in the case of man. The
varied aspects he presents in different countries are the necessary
consequences of those influences.'

Whether we advocate the doctrine of the origination of the human race
from a single pair, or from different races at different centres, we
are, in Dr. Draper's judgment, alike driven to the conclusion of the
transitory nature of typical forms, to their transmutations and
extinctions. In the former case, we can only account for diverse races,
having different shades of complexion, different varieties of skull,
etc., by the admission of the paramount control of physical agents, such
as climate and other purely material circumstances; in the latter, we
can only account for the varieties visible among the different races
themselves on similar grounds.

Variations in the aspect of man are best seen when an examination is
made of nations arranged in a northerly and southerly direction, the
differences of climate being much greater in this direction than from
east to west. These variations do not affect complexion, development of
the brain, and, therefore, intellectual power, only. But differences of
manners and customs, that is, differences in the modes of civilization,
must coexist with diversities of climate. An ethnical element is
therefore necessarily of a dependent nature; its durability arises from
its perfect correspondence with the conditions by which it is
surrounded. Whatever can affect that correspondence will touch its life.

With such considerations the author passes from individuals to groups of
men or nations:

'There is a progress for races of men as well marked as the
progress of one man. There are thoughts and actions appertaining to
specific periods in the one case as in the other. Without
difficulty we affirm of a given act that it appertains to a given
period. We recognize the noisy sports of boyhood, the business
application of maturity, the feeble garrulity of old age. We
express our surprise when we witness actions unsuitable to the
epoch of life. As it is in this respect in the individual, so it is
in the nation. The march of individual existence shadows forth the
march of race existence, being, inde