[Sidenote: Weak land tenure of hunting and pastoral tribes.]

A people who makes only a transitory or superficial use of its land has
upon it no permanent or secure hold. The power to hold is measured by
the power to use; hence the weak tenure of hunting and pastoral tribes.
Between their scattered encampments at any given time are wide
interstices, inviting occupation by any settlers who know how to make
better use of the soil. This explains the easy intrusion of the English
colonists into the sparsely tenanted territory of the Indians, of the
agricultural Chinese into the pasture lands of the Mongols beyond the
Great Wall, of the American pioneers into the hunting grounds of the
Hudson Bay Company in the disputed Oregon country.[106] The frail bonds
which unite these lower societies to their soil are easily ruptured and
the people themselves dislodged, while their land is appropriated by the
intruder. But who could ever conceive of dislodging the Chinese or the
close-packed millions of India? A modern state with a given population
on a wide area is more vulnerable than another of like population more
closely distributed; but the former has the advantage of a reserve
territory for future growth.[107] This was the case of Kursachsen and
Brandenburg in the sixteenth century, and of the United States
throughout its history. But beside the danger of inherent weakness
before attack, a condition of relative underpopulation always threatens
a retardation of development. Easy-going man needs the prod of a
pressing population. [Compare maps pages 8 and 103 for examples.]

[Sidenote: Land and food supply.]

Food is the urgent and recurrent need of individuals and of society. It
dictates their activities in relation to their land at every stage of