Picture - Cosmic Polymath

ii6 DESIGN IN NATURE
even then, be cumulative proof that a Creator produced both kingdoms ; but when it is found that the two kingdoms
dovetail into each other and interact at innumerable points, and are, in the widest and fullest sense, complemental
as regards their matter and much of their force, then the proofs of a First Cause, a Sustainer, and Regulator are, it
appears to me, indefinitely strengthened.
In considering magnetism, electricity, heat, and Hght we have to deal with the movements of the atoms
and molecules of matter, and of the ether which pervades space. Magnetism, electricity, heat, and light may be
said to merge into each other. They are all forms of motion, and are best treated together. A knowledge of
electricity is necessary to a comprehension of the others, and forms, in a sense, a prehminary inquiry.
The precise nature of electricity is unfortunately not yet quite understood. Recent researches, however, make
it all but certain that the old idea of an electric fluid must be abandoned. Electricity, there can be little doubt,
does not flow as water and other hquids do. When an electric current passes along a wire, the transference is effected
by continuous molecular action propagated within and outside the wire : the action extending to the atmosphere.
There is a movement of the molecules of the wire, and of the molecules of the ether between and outside those of
the wire in the atmosphere ; the latter constituting the so-called magnetic field. ^ Both sets of movements take
the form of waves, and the molecules rotate as well as vibrate or pulsate :
there are longitudinal wave and rotatory
transverse movements. The molecular action is primarily between neighbouring molecules ; the remote molecules
being afiected secondarily. The movements are not those of fluids streaming steadily in a particular direction
between the molecules, but vibratory wave movements of the molecules themselves in several directions ; the
advance or transference being due to what is practically a system of percussion, one molecule acting on another in
rapid succession not only in the wire but throughout space. The molecules have a vibratory progressive wave
movement in the aggregate. They have also transverse, rotatory, and, some think, spiral movements individually.
Each molecule has an environment to which it is confined, but the molecules as a whole have movements apparently
co-extensive with space.
Professor Trowbridge of Harvard University, in his work, " What is Electricity ? " ^ points out that when fluids
or compressed air are made to flow through tubes there is no disturbance outside the tubes in the surrounding
medium ; a magnetic needle placed outside the tubes not being affected. It is otherwise when a current of electricity
is passed along a copper wire. In this case, when a magnetic needle is placed in the vicinity of the wire it is
disturbed or deflected, showing that the atmosphere outside the wire is involved. The conducting wire is surrounded
by an atmospheric magnetic field, which influences substances placed in it. While it is convenient in popular
parlance to speak of the flow of electricity, and of electrical currents, it is necessary to make a distinction between
the passage of fluids in the ordinary sense and that of electricity. In electrical transferences it is the ether prin-
cipally which is concerned. That ether exists is all but proved by the transference of energy in magnetic in-
duction. When an electric current is sent through one circuit it begets a current in a neighbouring circuit. The
energy which disappears in the exciting current reappears in the induction current, and must have existed in the
space separating the currents during the transference. A medium of some kind (beHeved to be ether) is necessary
to convey the energy through the intervening space in question. The phenomena of light also involves the existence
of a medium.
" The old fluid theories impUed that when a body was electrified it had something upon it which was caUed
electricity. According to the modem views, we regard the ether around the body as charged with energy which is
the result^of the work we have done in charging the body. This energy in the ether is the energy of motion,
ihere is a^state of stram m the ether which we term a polarised condition. Around a positively charged body this
polarisation has a certam direction and a certain amount. With a negatively charged body this polarisation is
m an opposite direction. It is suggested that these polarisations may be Uke right-handed and left-handed
rotations or twists. When we electrify a conductor we store up energy around the conductor in the ether. The work
we do IS spent m changing the state of the medium. When a body is discharged, the medium returns to its original
state, and the energy is dissipated as heat in the electric spark or as heat in the conductor. The electric current
IS therefore the mamfestation of energy in the ether along the wire through which the current appears to flow. The
consideration of the rotation of the plane of polarisation of Kght by magnetic force led Maxwell to a theory of
magnetism which is called ' the hypothesis of molecular vortices.' Since there is good evidence for the beUef that
there is some land of rotation going on in the magnetic field, Maxwell investigated the condition of motion which
exists when a great number of very small portions of matter rotate on their own axes, these axes being parallel to
the direction of the magnetic force. The motion of these vortices does not sensibly affect the visible motions of
large bodies, but it can be supposed to affect the periodic motion of the medium which constitutes the phenomena
2 S^^^y,".'"
«?;P^'*'^d his belief that the ponderable
"'/I^.^
atoms vibrate, but with much smaller amplitude than the
inteinational ether "'ci
Scientific
nartinlPQ
Sencs. painoies.
London, 1897.