The revolutions of the seasons, with their alternations of temperature
and of length of day and night, the climates of different zones, and the
general conditions and movements of the atmosphere and the seas, depend
upon causes for the most part cosmical, and, of course, wholly beyond
our control. The elevation, configuration, and composition of the great
masses of terrestrial surface, and the relative extent and distribution
of land and water, are determined by geological influences equally
remote from our jurisdiction. It would hence seem that the physical
adaptation of different portions of the earth to the use and enjoyment
of man is a matter so strictly belonging to mightier than human powers,
that we can only accept geographical nature as we find her, and be
content with such soils and such skies as she spontaneously offers.

But it is certain that man has reacted upon organized and inorganic
nature, and thereby modified, if not determined, the material structure
of his earthly home. The measure of that reaction manifestly constitutes
a very important element in the appreciation of the relations between
mind and matter, as well as in the discussion of many purely physical
problems. But though the subject has been incidentally touched upon by
many geographers, and treated with much fulness of detail in regard to
certain limited fields of human effort and to certain specific effects
of human action, it has not, as a whole, so tar as I know, been made
matter of special observation, or of historical research, by any
scientific inquirer. Indeed, until the influence of geographical
conditions upon human life was recognized as a distinct branch of
philosophical investigation, there was no motive for the pursuit of such
speculations; and it was desirable to inquire how far we have, or can,
become the architects of our own abiding place, only when it was known
how the mode of our physical, moral, and intellectual being is affected