studying a given combination of geographic forces, must be prepared for
a momentous readjustment and a new interplay after any marked turning
point in the economic, cultural, or world relations of a people.

[Sidenote: Interplay of geographic factors.]

Skepticism as to the effect of geographic conditions upon human
development is apparently justifiable, owing to the multiplicity of the
underlying causes and the difficulty of distinguishing between stronger
and weaker factors on the one hand, as between permanent and temporary
effects on the other. We see the result, but find it difficult to state
the equation producing this result. But the important thing is to avoid
seizing upon one or two conspicuous geographic elements in the problem
and ignoring the rest. The physical environment of a people consists of
all the natural conditions to which they have been subjected, not merely
a part. Geography admits no single blanket theory. The slow historical
development of the Russian folk has been due to many geographic
causes--to excess of cold and deficiency of rain, an outskirt location
on the Asiatic border of Europe exposed to the attacks of nomadic
hordes, a meager and, for the most part, ice-bound coast which was
slowly acquired, an undiversified surface, a lack of segregated regions
where an infant civilization might be cradled, and a vast area of
unfenced plains wherein the national energies spread out thin and
dissipated themselves. The better Baltic and Black Sea coasts, the
fertility of its Ukraine soil, and location next to wide-awake Germany
along the western frontier have helped to accelerate progress, but the
slow-moving body carried too heavy a drag.

[Sidenote: Land and sea in co-operation.]