ture. He has improved wild fruits and vegetables by
cultivation, he has domesticated wild animals, he has harnessed the
water of the streams and the winds of heaven. He has tunnelled the
mountains, bridged the rivers, and laid his cables beneath the ocean.
He has learned to ride over land and sea and even to skim along the
currents of the air. He has been able to discover the chemical
elements that permeate matter and the nature and laws of physical
forces. By numerous inventions he has made use of the materials and
powers of nature. The physical universe is a challenge to human wits,
a stimulus to thought and activity that shall result in the wonderful
achievements of civilization.

360. =The Human Physique.=--Another element that enters into every
calculation of success or failure in human life is the physical
constitution of the individual and the group. The individual's
physique makes a great difference in his comfort and activity. The
corpulent person finds it difficult to get about with ease, the
cripple finds himself debarred from certain occupations, the person
with weak lungs must shun certain climates and as far as possible must
avoid indoor pursuits. By their power of ingenuity or by sheer force
of will men have been able to overcome physical limitations, but it is
necessary to reckon with those limitations, and they are always a
handicap. The physical endowment of a race has been a deciding factor
in certain times of crisis. The physical prowess of the Anakim kept
back the timid Israelites from their intended conquest of Canaan until
a more hardy generation had arisen among the invaders; the sturdy
Germans won the lands of the Roman Empire in the West from the
degenerate provincials; powerful vikings swept the Western seas and
struck such terror into the peaceful Saxons that they cried out: "From
the fury of the Northmen, good Lord, deliver us."

361. =Biological Analogies.=--The physical factor in society received
emphasis the more because society itself was thought of as an organism
resembling physical organisms and dependent upon similar laws. As a
man's physical frame was essential to his activity and limited his
energies, so the visible structure of social organization was deemed
more important than social activity and function. Particularly did the
method of evolution that had become so famous in biology appeal to
students of sociology as the only satisfactory explanation of social
change. The study