Man's physical universe





To concentrate thought and effort upon dividing existing things rather than

on the creation of new ones is a sure sign of degeneracy. It is the doctrine of

one who would take from others rather than create for himself. — Henry M.



Machines have made the United States the richest country in the

world. They have made it possible for more people to have abundance

and leisure. They have also brought serious social problems, many of

which our government is struggling to solve. It is important that these

problems be understood, because the most intelligent planning by our

government will not solve these problems without our whole-hearted


Modem Machines Are Combinations of a Few Simple Principles.

Leonardo da Vinci, the greatest inventor of history and also a great


invented the centrifugal pump, the dredge, the roller bearing,

the universal joint, the conical screw, the rope and belt drive, link

chains, bevel gears, and spiral gears.

The use of gears is an illustration of the way in which man magnifies

the force he is able to exert in order to do work more advantageously.

The rate at which work is done is

power. In order to accomplish a given

amount of work, less power is required

if the work is done more slowly; that

is, if the distance an object is moved

during a given time is decreased. The

use of the inclined plane is one method

of decreasing the vertical distance an

object is moved per unit of time. Thus it requires more power but less

time to climb a steep stairway than one that is not so steep. The


Much of the material in this Section was taken from the following publications of the

Machinery and Allied Products Institute, with their permission:

More Fads on Technology and Employment

Machinery and the A merican Standard of Living


Fig. 102.

The inclined plane.

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