Each kind of power requires its own special machinery so constructed
and adapted as to utilize it; hence, to be serviceable to mankind,
electricity demands machinery suited to its nature; what that is, will
be indicated in the following few paragraphs.
Electricity is a name derived from the Greek word _electron_—amber. It
was discovered more than 2,000 years ago that amber when rubbed with a
Fox’s tail possessed the curious property of attracting light bodies.
It was discovered afterwards that this property could be produced in
a dry steam jet by friction, and in A. D. 1600 or thereabouts, that
glass, sealing-wax, etc., were also affected by rubbing, producing
electricity.
Whatever electricity is, it is impossible to say, but for the present
it is convenient to consider it as a kind of invisible something which
pervades all bodies. While the nature and source of electricity are a
mystery, and a constant challenge to the inquirer, many things about
it have become known—thus, it is positively assured that electricity
never manifests itself except when there is some mechanical disturbance
in ordinary matter, and every exhibition of electricity in any of its
multitudinous ways may always be traced back to a mass of matter.
NOTE.—The great forces of the world are invisible and impalpable; we
cannot grasp or handle them; and though they are real enough, they
have the appearance of being very unreal. Electricity and gravity are
as subtle as they are mighty; they elude the eye and hand of the most
skillful philosopher. In view of this, it is well for the average man
not to try to fathom, too deeply, the science of either. To take the
machines and appliances as they are “on the market,” and to acquire
the skill to operate them, is the longest step toward the reason for
doing it, and why the desired results follow.
Electricity, it is also conceded, is without weight, and, while
electricity is, without doubt, one and the same, it is for convenience
sometimes classified according to its motion, as—