Chapter LIII: Section 60: Motive Power

It is assumed that all physical energy is derived more or less directly from the sun, whose rays combine: 1, heat; 2, light; 3, actinic or chemical power.

=Heat= may be obtained:

a. By direct use of the sun’s rays.

b. From any combustible material.

c. From chemical reaction.

=Light= does not separately develop power.

=Chemical reactions= are employed to develop heat, combustion, contraction, or expansion, as means of developing power.

From the foregoing elementary physical sources the following are the practical sources of our power for mechanical purposes.

Electrical power.

Magnetic power.

Tidal motion.

Falling water.

Descending weights.

Wave motion.

Wind.

Expansion of air or other gases.

Steam.

Explosives.

Fuels, hydrocarbons, &c.

These are employed in producing power by the following apparatus or motors:--

=Electric motors= driven from a dynamo, battery, or accumulator.

=Magnetic power= cannot be employed continuously as a motor, as it
gives out only as much as it receives.

=Tidal motion= can be utilised to drive any kind of wheel, see Water
Wheels, Section 90. It can also be stored in a reservoir, driving a
water engine as it flows in and out on the flood and ebb; or a
floating vessel may, by its rise and fall, communicate motion to
machines.

=Falling water;= for machines employed to utilise, see Water Wheels,