have the art of moving things to suit our
needs. Nothing can be truer than Tennyson's line, "We rule by obeying
nature's powers."

Chapter II. Forces In Production Of Wealth.

_Nature._--When men learn to meet their wants by exertion in accord with
nature's ways, they are said to use the forces of nature in production of
wealth. Every accumulation of materials for satisfying future needs
implies some control over natural objects. If advantage is taken of
natural motions or other activities to bring about larger accumulation,
the man whose plans secure this has gained control over, and so
property-rights in, the natural force which he has harnessed. The wind
caught by a sail and the water controlled by a dam contribute to the
power, and indirectly to the wealth, of the man who contrives to make them
move things for him. The directive actions of men necessarily appropriate
the natural objects which they use, together with all the qualities of
those objects.

_Energy._--Human exertion produces wealth, as we have seen, whenever it
anticipates and provides for future wants by securing at hand the things
to be used. So far as this anticipation includes control of forces or
qualities in nature, these natural agencies contribute to wealth of
individuals or communities. So voluntary human exertion is combined with
involuntary forces of outside nature to give wealth. No amount of gold in
Alaska is wealth until some human ability has appropriated it to human
uses; but the mere fact of locating a claim for mining purposes gives the
prospector advantage over any other man because of his foresight. So every
activity of nature may become a factor in wealth by human ingenuity in
making it useful.

_Natural forces._--Such natural agencies for producing wealth are seen in
the simple properties of material bodies, such as the metals or woods or
grains or fruits or flowers possess. We secure these properties for our
uses. Gravity, sound, heat, light, electricity, chemical affinity,
crystallization, even life itself, are names for certain forms of energy
in nature which men are using more or less to meet their wants. Whenever
exertion is needed to provide for using these, the thought of wealth is
connected with the forces themselves. The fish in the sea and rivers
become wealth to one who has caught them, and even more distinctly the
property of the community which has protected them in breeding. Sunlight
may reach all alike in