ON
LMATTER AND ETHER.








ON
MATTER AND ETHER
THE SECRET LAWS
OF PHYSICAL CHANGE.
BY
THOMIAS RAWSON BIRIKS, M.A.
RECTOR OF KELSEALL, HERTS
FORMIERLY FELLOW OF TRINITY COLLEGE, CAMBRIDGE
AUTHOR OF "THE DIFFICULTIES OF BELIEF" &c.
MACMILLAN AND CO.
AND 23, HENRIETTA STREET, COVENT GARDEN,
1862
[I77te r'ight of translcatio l is r'eserved.]




(Tambrittbe:
PRINTED BY C. J. CLAY, M.A.
AT TIHE UNIVERSITY PRESS.




PREFACE.
THE Theory unfolded in the present Essay, whatever
may be its merits or defects, is not the hasty production of
a moment. It is twenty-eight years since the first steps
were taken in the line of inquiry, -which has now  at
length assumed a consistent and connected form.  Three
main elements of the theory, the conclusion from the law
of gravitation with regard to the nature'of the atoms of
matter, the constitution of chemical elements, as the firs't
step in composition of these material monads, ancl the large
part played by rotatory motion and centrifugal atomic
force, in nearly all branches of physics, were then imperfectly traced out in connexion with various kinds of
phenomena, and became settled convictions of my mind.
A second step, after some little interval, was to discern the
absolute need of admitting ether distinct from matter, as
proved by the phenomena of light and electricity, and
along with this, the consequent necessity for three distinct
laws of central force, to explain their nature and mutual
action.  From these data alone consequences were traced
out, at intervals of reflection, such as other engagements
would allow, which seemed gradually to take a definite
shape, and reveal the main classes of phenomena, known
to science, as necessary results of such a constitution of the
two primary elements. One difficulty, however, hindered
me from ripening the theory into a definite and tangible
form, and made me unwilling, in spite of the many




Vi                     PREFACE.
interesting lines of speculation it opened, to offer it to
the thoughts and criticism of men of science, until it had
been overcome. I was long unable to conceive such a relation of the constants, required by the laws of force, as
would satisfy the phenomena of light and of the cohesion of
solids, and also make mechanical structure a direct and immediate result of chemical composition. It seemed needful
to allow a wide interval between the chemical atom, the
first result of composition, and the molecule, on which cohesion and solid structure depend.  In a later review of
the sutjeet, by comnbinning the known data, and adopting
an inductive course, this difficulty, I believe, was finally
removed. Its source was the assumption, on grounds of
apparent simplicity, of the lowest possible powers, the
inverse third and fourth, for the two unknown laws of
force to be determined.  By the course of reasoning unfolded in the earlier chapters of the Essay, this source of
perplexity was removed, while the main features of the
theory, as it had for many years been developed, remained
unaltered. All recent discoveries, during the thirty years
since I became possessed of some of its main outlines,
seem to me to have only confirmed, by anticipation, its
substantial validity and truth. With the strong hope that
it will be found to supply the true key to many of the undisclosed mysteries of nature, which have hitherto baffled
all attempts at harmonious and consistent explanation,
I commit it now.to the candid and thoughtful reflection of
men of science, and to the blessing of Him in whom are
hid all the treasures of wisdom and knowledge.
KELSmALL RECTORY,
S6et. 23, I862.




CONTENTS.
CHAPTER                                                       PA.G'
INTuODUCTION   e1
I. On Matter and Ether.                     7
I.  The Laws of Affinity and Repulsion..        19
III.  On the General Forims of Matter.                       27
IV. On the Igneous Forln of Matter andl the Phenomena of
Comets                                               45
V. The Nature and Properties of Light                        56
VI. On the Chemical Elements in General.                     85
VII.  On the Four Simplest Elements  99
VIII. General Relations of the Chemical Elements t. 119
IX. On Statical Electricity. 134
X. On the Electric Cu tenlt..    155
XI. On Electro-magnetism.                  176
XII. On Magnetism and Diama-gnetism. 190
XIII.  On Terrestrial Physics in General                        0.  202








ON MATTER AND ETHER,
OR THE
SECRET LAWS OF PHYSICAL CHANGE.
INTRODUCTION.
SINCE the discovery of the Law of Gravitation, by
Sir Isaac Newton, an immense progress has been made
in every branch of physical science. Chemistry and electricity were then in their infancy, and galvanism quite unknown. But the advance, of late years, has been rapid
and continual. Secondary laws of high importance have
been discovered, as in the Undulatory Theory of Light,
researches on specific and radiant heat, electrical attraction
and induction, atomic proportions, and the laws of crystallization. All the subtler influences of nature, light,
heat, electricity, magnetism, chemical affinity, crystalline
polarity, are found, more and more, to be intimately related to each other. AMen of science feel themselves to be
on the verge of some great discovery, but the key which
can unlock these various secrets of nature has not yet been
attained.
I




2              ON MATTER AND ETIIER.
The theories which have been proposed, to explain
separately some one class of these phenomena, are plainly
insufficient. Thus electricity has been referred, sometimes
to one, and sometimes to two electric fluids. The second
hypothesis has been developed by Coulomb, Poisson,
Whewell, Murphy, and other analysts. But the reasons
why these two fluids should combine with matter, and
nearly all their laws of combination, remain wholly unexplained; while the supposition itself, of two such fluids
differing only by a positive and negative sign, is very
remote from natural probability. Again, magnetism has
been referred, by Amp're, to spiral systems of electric
currents. But the needful postulates, that two elements of
electricity attract each other, when they move in the same
direction at right angles to the line of junction; that
they repel with the same force, when they move opposite
ways, and with half the force, when the motion is in the
direction of their distance, have none of the simplicity of
ultimate laws. No explanation at all is given, why electricity in motion should attract differently from its state
of rest, or why currents in constant revolution should exist
around the particles of a magnet. The theory may have
its use as a landing-place in the ascent of science, but
the true nature both of electricity and magnetism clearly
remains still to be discovered.
Again, theories of heat have been constructed, by
Fourier and others, with great analytical ability, on the
hypothesis that caloric is a fluid, condensed around the
molecules of matter, and radiating constantly from  one
part of it to another. But the later discoveries of the
Polarization of Heat, and of its equivalence with mechanical
force, have almost entirely overthrown the idea that it is a




INTRODUCTION.                   3
distinct and separate fluid.  All these theories, of two
electric fluids, a magnetic fluid, and a fluid of heat, are
not only fragmentary, but divergent, and in their results
contradictory to each other.
Several attempts have been made to propound some
view of the constitution of matter, which may account for
the various forms of molecular action.  The theory of
Boscovich was one of the earliest. Each particle was supposed to be a point, endued with attractive and repulsive
force; the curve of force being such as to cross the
axis several times, or to have several neutral distances,
where the force changes from  attraction to repulsion,
the repulsion tending to infinity at one limit, and the
attraction varying as the inverse square at the other.
But a law of force with these conditions is so complex,
and admits of so many arbitrary varieties, as to make
the hypothesis highly improbable, and practically useless.
The modern discoveries in optics, also, seem to exclude
the notion that one kind of matter alone will account for
all the varied phenomena of the universe.
The first rule of philosophical reasoning, laid down by
Sir Isaac Newton, is to. this effect: "No more causes of
natural things are to be admitted, than such as are both
true, and sufficient to explain their appearance." He says
further, at the close of the work: "' Whatever is not deduced from the phenomena is to be called an hypothesis;
and hypotheses, whether metaphysical or physical, whether
of occult qualities or mechanical, have no place in experimental philosophy."
The rule, thus stated, is clearly open to a very weighty
objection. If the true cause is already known, all inquiry
is superfluous. But if not known, how can it be the test
1 2




4              ON MATTER AND ETHER.
of a sound induction?  Dr Whewell has observed, more
accurately, that hypothesis is essential to the progress of
science; that few discoveries have been made, till several
hypotheses have been tried; and that the test of a sound
induction is not the rejection of all hypothesis, but a readiness to invent those which shall be most promising, and
to abandon those which have been proved insufficient. It
is like the use of a bunch of keys in unlocking a door.
lie succeeds best who only tries the keys which have some
apparent resemblance of size to the lock itself, and who,
instead of trying to force the lock with a wrong key, lays
it aside quickly, and tries another. There can be no more
complete test of an hypothesis than its power to explain all
the phenomena; and the word " true" in Newton's rule,
may thus appear not only superfluous, but to involve a logical contradiction. The real meaning, however, of Newton,
was probably this; that a cause already accepted for one class
of phenomena, if it will also explain another class, is preferable to one which explains the latter alone.  Thus gravity
was a known fact with regard to bodies on the earth's surface; and since it would account also for the moon's revolution, and the orbits of the planets, it was to be preferred to
any explanation which would apply to the latter only. The
principle, thus understood, is the same which has been well
called "the consilience of inductions," and seems to lead
to the following principles or rules of inductive inquiry.
AxIOM I. There are only two tests of the truth of
any physical hypothesis; its fitness to account for all the
phenomena, and its simplicity.
AxIoiI II. The simplest hypothesis, which offers any
hope of explaining the facts, ought first to be tried; and




INTRODUCTION.                   5
more complex ones, only when the simpler has been tried,
and proved to be insufficient by careful examination.
AxIoM III.  The first step in the required proof of
any hypothesis, is when it can be shewn to produce, by
natural consequence, all, or nearly all, the same classes of
phenomena, which a true theory is wanted to explain.
Such an hypothesis may be called probable, and has a
claim to fuller development.
AxIoM IV. An hypothesis is not only probable, but
almost certainly true, when, on being developed, it yields a
large variety of measurable results, which agree in quantity
with the results of direct experiment.
AxIoMi V. The simplest hypothesis is that which
includes the smallest number of arbitrary postulates, such
as distinct laws of force, constants of force, and constants
of distance.
The first result of these simple axioms, when applied
to the great problem of physical science, still unsolved, is
to sweep away all the specific fluids, which have been conjecturally proposed, each for one limited class of phenomena; the two electricities, the fluid of heat, or caloric,
and the magnetic fluid. The phenomena of optics seem to
compel the admission of a luminous ether, besides matter,
of immense elastic force. Until it has been shewn that
this double admission, of ponderable matter, and of luminiferous ether, is insufficient to explain the phenomena, the
recognition of any further varieties, or of fundamental diversities in matter itself, or of many distinct and unchangeable
material substances, is opposed to the true laws of a sound




6             ON MATTER AND ETHER.
induction. But before the inquiry can make any considerable progress, it will plainly be needful to form  some
clear and definite conception with regard to the real nature
of both these kinds of substance, and the laws of mutual
action which must be supposed to exist between them.
Such will be the first object of the present investigation.
It will then be endeavoured to trace out, in order, the main
consequences of the fundamental hypothesis, and their correspondence with the known phenomena of physical
change.




CHAPTER I.
ON MATTER AND ETHER.
1. EIERY particle of matter attracts every other particle, with a force varying inversely as the stuare of the
distance between them.
This is the great discovery of Newton, which must form
the natural starting point for every further advance in physical science. The history of Astronomy for two centuries
has consisted mainly in the development of its results.
But rich and fertile as its consequences, in one direction,
have proved to be, those which flow from  it in another
have never been traced with sufficient clearness.  When
examined narrowly, it points to conclusions of great importance and scientific value.
2. Every particle is eitzer a mathematical point, or else
contains such a point, as the true centre ~fom whzich tzhe
attraction proceeds.
By the fundamental law, the attractive power varies
inversely as the square of the distance.  But distances
cannot be measured from a space of finite dimensions. They
nust be measured from some point only.  Hence, if the
attractive forces exerted by a particle on every other are
determinate, then the point from which they emanate, or




8               ON MATTER AND ETHER.
from which all the distances are reckoned, must be determinate also.
3.  There is no reason for admitting, in the particles of
vnatter, a solid sphere of repulsion, enclosing the trite centre
of force, and distinct from it.
First of all, such an assumption is very complex and
arbitrary, and thus violates the first and second Axioms of
inductive inquiry.  A central force, emanating from a definite point or centre, is proved to exist. The hypothesis introduces these further elements; an arbitrary radius of the
solid nucleus, an arbitrary shape of the atom, a surface of
abrupt and infinite repulsion, a structure  unalterably
rigid, and also an arbitrary relation of the centre of force
to the supposed solid nucleus. None of these things can
be rightly assumed, while there is no clear necessity for
the supposition.
Again, two of these assumptions are opposed to all
the conclusions from  experience.  They would rest a
scientific datum upon a popular impression, which exact
science disproves. In compound bodies, repulsion always
begins at some distance from  the surface.  A  sudden
change, then, from attraction to infinite repulsion, has no
analogy in its favour. The most solid bodies, also, have
always some elasticity, and a case of perfect rigidity is not
to be found.  The hypothesis, then, of a rigid, solid
nucleus, not only finds no warrant in the law of gravitation itself, but is also opposed to all known analogy.
Hence, by Axiom II. it is inadmissible, until it can be
shewn that a simpler hypothesis, the natural result of the
law alone, fails to satisfy the actual phenomena.
4.  The simplest view of matter, derived at once from
the law of gravitation, i's tZhat it consists of monaRcds, or move



CHAPTER I.                        9
able cenltres of force, unextended, but definite in position,
which attract each other with a force varying  inversely as
the square of the distance between the centres.
This conception, of points that are centres of force,
results plainly and unavoidably from  the nature of the
law  of gravitation.  Any further conception of the constitution of matter is an unproved addition.  Also the
conception, in this simplest form, involves no greater metaphysical difficulty than may be shewn to exist equally in
every other conception of primitive or constituent atoms.
5.  The particles of matter, so constituted, could never
coalesce with each other, and thus lose their inzdividual being,
or disap)Iear.
Let us suppose two particles to fall from rest in the
line joining their centres. Unless all other particles were
disposed with perfect symmetry in reference to this line,
and were also at rest, there must be some lateral disturbance.  But in this case they will describe ellipses round
their centre of gravity, and after their nearest appulse,
will recede again.  Hence it is plainly impossible that
any two particles, so formed, should coalesce together.
6.  T/he law of gravitation, in matter so constituted, will
not alone account for the cohesion and solid structure of
bodies.
Let us assume one thousand millionth of the earth's
radius (=~ in. or 6- millimetres nearly) for a linear unit.
Assume further that a small sphere of this radius, and
of the density of the earth, has its particles symmetrically
placed, and 104 for the number in its radius, or its mean
linear density. The attraction of this sphere on an atom at
its surface will be 109 less than the atom's weight. The attraction of atom on atom at that distance will be -7r.103+9




10             ON SMATTER AND ETHER.
less than the weight of an atom, and at their own mean clistance 4v. 100+' less than the weight. Hence two atoms must
be 64720x102 nearer to each other than this mean distance,
that one may have a cohesive action on the other equal
to its own weight, so as to retain it in permanent connection.  There is plainly no arrangement of the particles which can satisfy this condition, and retain the
least semblance of a solid structure. We must therefore
look elsewhere for the explanation of cohesive force and
solidity.
Two alternatives are possible. Either the law of gravitation must be modified for small distances; or there muSt
be some other substance, distinct from common matter, on
which the phenomena of cohesion depend.
7. A seif-repulsire ether, wholly distinct frnom conmon
nmatter, also exists, and is cditfsed widely throuq/zout all
known space.
The closing words of the Principia are like a prophecy,
and shew  in what direction the second main series of
physical discovery must be attained.
"I might add something about a certain very subtle
spirit, which pervades dense bodies and lies hid in them;
by the power of which, bodies at very small distances
attract each other, and when brought close together, cohere; and electrical bodies act at greater distances, attracting and repelling neighbouring bodies; and light is
emitted, refracted, and reflected, and warms bodies; and
sensation is excited, and the limbs of animals are moved
at will, through vibrations of this spirit, propagated
through the nerves to the brain, and from the brain to
the muscles. But these things cannot be expounded in
few words; nor is there extant a sufficient abundance of




CHAPTER I.                    11
experiments, by which the laws of the activity of this
spirit could be accurately determined."
In Sir Isaac Newton's Op2tics, the same thought appears in the modest form of queries.
"Is not heat conveyed through a vacuum by the vibrations of a much more subtile mediumn than air?  Is not
this medium  the same by which light is refracted and
reflected, and communlicates heat to bodies, and is put into
fits of easy.reflexion and transmission? Do not hot bodies
communicate their heat to cold ones by the vibrations of
this medium?  And is it not exceedingly more rare and
subtile than the air, and exceedingly more elastic and
active?  And does it liot readily pervade all bodies?
And is it not, by its elastic force, expanded through all the
heavens?"
Since the days of Newton, science has done much to
supply the deficiency of experiment to which he alludes.
The Undulatory Theory of Light, in. displacing his own,
has lent new evidence of the truth of his modest conjectures. In the hands of Young, Fresnel, Malus, Cauchy,
Airy, Lloyd, and Stokes, it has come very near to astronomy in the singular and beautiful triumphs of its analysis,
and the large variety of curious phenomena which have
been explained. But its first postulate is the existence of
an ether,, such as the sagacity of Newton divined long ago,
and indeed the same by which Huyghens, his contemporary,
had already solved the phenomena of double refraction.
This ether must be diffused through all known space.
For light is caused by its undulations, and this reaches
us from  stars immensely distant.  Its elasticity, also,
implies its diffusion in all directions, and not merely in the
lines of the transmission of stellar light.




12             ON MATTER AND ETHER.
Again, this ether must be self-repulsive. If its particles
were mutually attractive, they would evidently condense
around centres, where there was any excess of density
at first, and light could not pass from one of these condensing systems to another. Mutual repulsion, therefore,
must plainly be one of its fundamental laws.
The denial of the existence of this ether, when confirmed by so many discoveries of modern times, though
AM. Comte in his Lectures ventures to style.it a mark
of superior wisdom, is a step backwards into the nonage
of science. To recognise a cause, which is pointed out
by many classes of phenomena converging together, is
just as imperative a law of sound philosophy, as to reject
and refuse every really superfluous element.
8. No secondc flid, of caloric, electricity, or mnagnetism,
ought to be recoqnised, until it can be proved that the action
and reaction of common matter and a luminous ether are
incapable of sztpplying the required explanation.
This results at once from the second Axiom.  The
simplest hypothesis may justly claim to be the first examined. That which recognises matter alone, is disproved
by the phenomena of cohesion and of light. Next in order
of simplicity is that which recognises both matter and a
luminiferous and elastic ether, but no other fundamental
variety. The ready adoption of so many hypothetical fluids,
as have been often proposed, repels thoughtful students,
and makes them ready to question the existence of any
ethereal medium whatever, distinct from common or ponderable matter. The line of safe induction lies between
these two extremes; and the most able analysts and experimentalists already tend to this middle view.
9.  The existence of matter and ether requires the ad



CHAPTER I.                     13
missson of three, and only three, laws of force for their
mutual action.
First, matter acts on matter, and the law of its action
is already known, being one of mutual attraction, inversely
as the square of the distance.
Secondly, matter must act on ether, and ether on
matter.  This force must also be attractive, since otherwise the ether would not be condensed around the material atoms, nor give rise to cohesive affinity between
neighbouring particles. Its exact law of force is hitherto
unknown.
Thirdly, ether acts on ether. This force must be repulsive; since otherwise the ether would converge into
patches, and not be diffused through space, as the transmission of light from the stars in every direction evidently
proves it to be.
Fourthly, these two unknown laws cannot be the same
with that of gravitation,, or vary only as the inverse square.
In this case all three forces would increase and diminish
together, and cohesive attraction and ethereal repulsion
would have the same relative amount at great as at small
distances. There could thus be neither increase of cohesion, nor of resistance to pressure, however closely
particles  were  packed  together.   These two  forces,
then, must follow some higher law than the inverse
square.
10.  The ether of the universe greatly exceeds ink quantity, or in the number of its atoms, the amount of ponderable
matter.
The force of cohesion, by the hypothesis, must depend
on the presence of ether along with the material atoms.
Hence, even in solids and liquids, the number of ether




14             ON MATTER AND ETHER.
atoms must exceed that of the material atoms.  But
the planetary and stellar spaces are all filled with ether,
and nearly voidl of matter. The space of the solar system
half way to the nearest stars, exceeds the bulk of the sun
more than 1022 to 1, or ten thousand trillion times. It does
not seem likely that the mean distance of the monads
of matter can be much less than that of the free ether
in space. We may conclude that the number of ethereal
is immensely great, compared with that of the material
atoms.
11.  The mean distance of the particles of free ether
must be less, and is probabljy far less, than one ten millionth
of an inchz.
The violet rays of light make 60,000 undulations in one
inch. With the limit assumed above, there would be only
167 ether particles in the length of a wave. In like
manner 250 would be the number in the length of a red
ray, and the difference about 80. It seems plain that,
in a discontinuous medium  of the kind suppposed, no
vibration can be propagated to any distance, of which
the length is not some multiple of the mean interval from
atom to atom. But the black lines of the speculum divide
it into a much greater number of different shades or kinds
of light. Hence it seems to follow that the distance of the
atoms must be less than  oo0 ooo in. and may be very
greatly less.
12.  The pressure of the ether on any surface must be
immensely great.
The pressure of common air, at the earth's surface, is
nearly fifteen pounds per square inch.'Now when two media
are compared, the velocity of a vibration varies as the
square root of the pressure, or modulus of the elasticity.




CHAPTER I.                     15
The velocity of sound, however, apart from its increase
by the momentary heat, is only 916'3 feet per second,
while that of light is 192,000 miles. The ratio is thus
1,106,360 to 1. The ethereal pressure, then, must be
1,224037,000000 times greater than that of atmospheric
air, or 18~ billions of pounds to the square inch. It is
plain, then, how powerful must be the action of what are
usually called the imponderable elements, or the mechanical forces, which light, heat and electricity, bring continually into play.
13.  Thie action of matter on ether must vary as the inverse cabe or some hlqher law, and the repulsion of ether on
ethzer, as the inverse fourth, or some ziqgher integer power.
First, the principle of the second Axiom requires us
to assume integer, rather than fractional powers, for the
two unknown laws of force, until decisive evidence to the
contrary can be found, since the assumption is evidently
far simpler.  The nature of cohesion, also, and ethereal
action, evidently requires inverse powers.  But the action
of matter on ether must increase more rapidly than gravitation for small distances, or else cohesion would not be
limited to such distances.  Hence the inverse cube is the
lowest admissible power.
Again, the repulsive force of the ether must vary more
rapidly than the affinity of matter for ether, since otherwise there would be no limit to the condensation, and
attraction would increase the fastest with the density of
the mass.  The inverse fourth is the lowest power which
can satisfy this first condition. Reasons, however, will
presently appear for assuming still higher powers for the
true laws of nature.
14.  The Three Laws of Force imply two inadependent




16             ON MATTER AND ETHER.
constants, and two others result from the actual constitution
of the ether in splace, and of material bodies.
Because the action of ether on matter and ether follows
two different laws, there must be some distance at which
they are equal, or have a fixed proportion. The distance
at which the attractive power of a monad of matter is half
the repulsive power of a monad of ether, will be a First
Constant.  The distance at which the gravitation  of
matter to matter, and the repulsion of ether for ether, are
equal, will be a Second, or Mean Constant. The distance
at which the affinity of matter for ether is one half the
attraction of matter for matter, will be a Third Constant.
The Second, or Mean Constant, is determined by the
two others. It will be a mean proportional when the powers
are equidistant, and will divide the ratio as m -2: n — m, in
other cases, where mn is the index of affinity, and n of repulsion.
Again, the self-repulsion of ether implies its equable
diffusion through space, apart from the condensing power
of material atoms. There must therefore be a certain
mean distance, on which its elasticity, and the propagation
of light and radiant heat depend, and which will modify
every kind of molecular action. This may be called the
Ether Constant.
A cubic inch of water must contain a certain number
of material monads, on which its weight depends. If
these are all arranged symmetrically, at right angles, they
will define a certain mean linear distance of the monads of
matter, when the density is one. This distance may be
called the Solid Constant. When we know the density of
any body, and the number of monads in its chemical atom,




CHAPTER I.                    17
the mean distance of those atoms will be deduced immnediately from this solid constant.
15.  To determine some general relations amzong tlese
constants.
Let 10-n, 10-n, in inches, be the Ether and Solid Constants.  The log. in grains, of the weight of a cubic inch
of water, is 2'40219.  The Earth's attraction, assuming
its density to be 5'5, exceeds that of a cubic inch of water
at one inch distance, log = 9 39790.  But the action of one
cubic inch on another must exceed that of one atom  onl
another, as 10%n.  Hence 6n + 699571, or 6n —+ 7 nearly,
will be the neg. log. for the force in grains, exercised by
one material monad on another at one inch distance.
Again, the pressure of the air on a square inch is about
14'62 lb. = 102340 grs., log = 5'01005. But the ratio of the
velocities of light and sound, apart from the heat of compression, has its log=6'04390.  The pressure in elastic
fluids is as the square of the velocity of vibration. Hence
the logarithm of the ethereal pressure, in grains per square
inch, = 17'09785, or 125270 billions of grains.
The tenacity of a square inch bar of steel is about
134,000 lb., or nearly 109 in grains. The cohesive action
in a substance, density = 1, with its monads evenly disposed,
is probably less, or its log = 9 - x, where the value of x
depends on the chemical atom and structure, and the
density.
If now we assume the Ether and Solid Constants to be
equal, and the cohesion of steel to be nearly the same as
of matter evenly disposed, density = 1, we lhave 17, 9, and
-(2n+ 7), for the common logarithms of the repulsion,
affinity, and gravitation, of 102o or 102"" monads on a like
number, on the surface of a square inch, and at a dis2




18             ON MATTER AND ETHER.
tance, each from each, of 10-"'. From this first comparison, then, it would seem to result that the Ether Constant, if not lower, must be nearly as low as the First
Constant, since the monads of ether must have a longer
mean distance, that the cohesion may equal the ethereal
pressure, as deduced from the immense velocity of light
compared with sound.
The thickness of a soap-bubble, before it bursts, has been
proved to be only four ten-millionths of an inch. Hence n,
the index for the Solid Constant, cannot be less than seven,
and may be much greater. In like manner, it follows
from the waves of light, that the mean distance of the
ether monads must be less than one ten-millionth of an
inch, or mb greater than 7. But other facts lead to the
inference that both of these indices have a much higher
value, and that the mean distance of the monads of ether
and atoms of matter is very considerably lower in order
of real magnitude.




CHAPTER II.
THE LAWS OF AFFINITY AND REPULSION.
16.  To determni'ne the general relatweons of lVatter and
Ethers, under laws of Affinity and  ehulsion, following a
hihqer power of the dcistance than the Inverse Square.
Let an atom of matter be placed in an ocean of free
ether, and attract it by the law of the inverse cube, or by
some higher power. It will be nearer to one monad of
ether than to the others, or will become so by their motion,
and will therefore be more strongly attracted by it, and
attract it in return.  The other monads, repelling the
ether, and attracting the matter, will impress on the two a
rotatory motion. But the centrifugal force produced by
their mutual action, or that of the surrounding monads,
will not, with the inverse cube or any higher power, be
equal to the increase of the direct force. They will thus describe a rapidly decreasing spiral, in which the line to the
centre is finite.  Hence the two atoms must coalesce with
an infinite force, and then remain inseparable.
This process of elective affinity, if the ether particles
are in great excess, will continue until every monad of
matter has combined with one of ether, so as to form a
double or conjugate atom. This dual aton will be neutral
2-2




20              ON MATTER AND ETHER.
to other dual atoms at the distance of the First Constant,
where the one repulsion will balance the two affinities; and
will be neutral to free ether atoms at a slightly greater
distance, depending on the two laws of force. There will
be a strong attraction at greater distances, and a still
stronger repulsion at less distances.
All further coalescence of these double atoms with each
other, or with the monads of uncombined ether, will be
impossible. For when the distance is less than the First
Constant, the repulsion will be greater than the sum of the
two equal affinities, and at half the distance be at least
twice as great; or if the indices of the powers differ by
two, four, or six, it will be four, sixteen, or sixty-four
times greater. Hence we shall have two kinds of centres
of force only. The first consists of double monads, of
matter combined with ether, following a double law of
force, with a positive and a negative term. The second
consists of free or uncombined ether, obeying its own simple
law of self-repulsion.
The further relations of the dual monads, which we
may call material atoms or units, to each other and to uncombined ether, will depend on the relation between, the
First and the Ether Constant. If the First be much less
than the Ether Constant, or mean distance of the free
ether monads, then each particle of matter will condense
around it a series of ether particles up to and beyond the
limit of that mean distance, so as to form an ether atmosphere. The constitution of the central part of this atmosphere will depend almost entirely on the law of central
force, and the outmost strata alone will be much modified
by the compressing force of the free ether. But if the
First Constant equals the Ether Constant, only the nearest




CHAPTER II.                     21
ether monads will experience a very sensible compression
by the central force, and the others will be very slightly
compressed, because the attracting power of the centre will
be only a small fraction of the pressure from the nearest
ether monads. In this case each particle of matter may
have a single, double or triple line of attached ether monads, but not an ether atmosphere of dimensions much
larger than the distance of its component monads. Again,
if the First Constant were much larger than the Ether
Constant, the cohesive force would bear a very small
proportion to the repulsion of the ether, and a solid and
coherent structure of bodies would be rendered impossible.  Our choice is thus restricted to the two former alternatives alone.
17.  To determzine the condensation of ether, apart f.rom
external pressure, with different assumed laws of Affinity/
and -Repulsion.
Let m, n denote the indices of affinity and repulsion,
x any distance from the centre of force, and r the linear
density, or number of ether monads in the unit of distance.
Taking an infinitesimal cylinder of unlimited length,
ar'dx will be the differential of the mass, and arC3-xdx
that of the force acting on it from the centre.  But the
pressure is produced by ar2 monads, each at distance I
from the next, or having a repulsion as ra. The differential
of this pressure must be equal to the total action of the
central force on the differential of the mass.
Hence d.ar+2 = (n + 2) ar  c+ dr = ar3x-'"dx,
and, dividing by r' and integrating
(n   2) ( - 1) r.-' = (_  - 1 \ xl-   c.




22              ON MATTER AND ETHER.
Or, varying the form of the constant,
r = c /     + loan
where ca is the density of the free ether, apart from the
attraction.
Neglecting the external pressure,
I-mr 3-Con
-- =X-1;.X r3 = 8_3x *The mass of a sphere, whose density follows this law,
4   n-1 - I..
~     -ill be. s n-i. And hence the cohesive action
3   n-Adnh 
of two such atoms on each other, if nearly the same as
when their atmospheres are condensed at the centres, will
have for its negative index rn' = n- 3          To satisfy
the conditions, this force must vary by a higher law than
the inverse square.  But if rn= 3,   = 4,  -' =2, and if
= 3 n = 5, m' = 1.  Hence, apart from  external pressure, and in the case of matter surrounded by ether atinospheres, the law of the inverse cube fails to satisfy the
rapid change of cohesive force that results from the phenomena.
If mn = 4,  = 5, m'= 3; and if n = 4, n = 6, nZ' = 24;
if in = 4, n = 8,'= 2.  Hence, in the same case, it may
still be doubtful whether the increase and decrease of cohesive force would be sufficiently rapid, even with the
law  of the inverse fourth power.
If m = 6, n = 8, in'= 5X; n = 6, n = 10, An'= 42; n = 6,
n= 12, m'= 4-; and in all these cases the actual law for
the composite action is higher than the fourth, so as to
satisfy the probable conditions, but exceeds it less, as the
index of repulsion is increased,




CHAPTER II.                      23
18.  To determine, by a first ap-proximation, the arranyement of ether atoms along a single radius, neglecting,
as before, the action of thefree ether.
A  single atom  will plainly be in equilibrio at the
neutral distance for ether, which exceeds that for matter in
the ratio'-Q/2.  Taking this for the unit, we may, in a
first approximation, suppose the attraction of the central
matter to be balanced by the repulsion of the one ether
monad, which lies nearest it towards the centre, and that
the other ether monads on the two sides nearly compensate
each other.  Let cao, a1,, a2, ct%, &c. be the successive
total distances of the ether monads from the centre; also
n = a (n- m2) and an?-7 = br.  Then br -b,-l= b,.a and
br=r_ -+    nearly.  Thus (+           )-m-,  will nearly
represent the successive distances of the ether monads,
and the number of those in the distance 1 will be
-1, nearly.
n -- 97
Applying this result to the case of spherical atmospheres of different radii, and putting; for the number of
monads, or the mass of condensed ether.
= 3, n = 4, /~ =             q85~7r.    n = 6, n = 8, / = 85vrr
m  4,  - 5 / = 166~ 7ir5.   m=6, n=10, /=-205 Orr~.
m = 4, n = 6, u = 367rr.     mq = 6, n  12,      IO -10 7rr.
All these relations will be essentially modified, if the
ether constant be nearly or quite as small as the first
constant, or the pressure of the free ether has a sensible
proportion to the forces which balance each other at the
neutral distance.




24              ON MATTER AND ETHER.
19.  To dedcce the probable Lazv qf Afinity from  the
compcar'ison qf weight and cohesive force~
The tenacity of a square inch of steel, the highest
known, is about 134,000 pounds, or nearly 10o in grains.
But the gravitation of one cubic inch towards another, density 1, at one inch distance, is 10-7 in grains nearly. Hence
the neg. log. for atom on atom  at that distance, is 6n + 7,
at the distance 10O-' it is 4n +7, and for 10"2 atoms, or
the action of each stratum on the next, 2n + 7. Assuming
the former to represent the cohesive force of two adjacent
strata in the uniform arrangement, this exceeds gravity as
10 2n',: 1.  Supposing the tenacity to result entirely from
the mutual force of the particles nearest to a plane section,
and f to be the index of affinity, then 2n + 16 - (f- 2) n
will be the logarithmu of cohesion + gravity, at one inch
distance. But general experience, and the special experiments of iMr Baily on the earth's density, tend to shew
that cohesive force is small, if not quite insensible, even
compared with the general force of gravitation (which is
very small itself), at one inch distance.  lHence we must
have (f- 2) n > 2n + 16, or (f - 4) n> 16. This seems to
prove that cohesion nmust follow even a higher law than
the inverse fourth power, and can only agree with the inverse fifth, if n is > 16, or the mean distance of the material particles not greater than 100 trillionths of an inch.
The difference between the cohesion of steel, and of
the hypothetical arrangement of monads in matter of density one, may a little modify these values.  But since the
disproportion is probably far less than 1016, it will not
affect the main conclusion, that no inverse power lower
than the fifth can satisfy the conditions for the law  of
affinity.




CHAPTER 11.                    25
Since the law of gravitation is the inverse square, it
seems more simple to assume even powers for the other
laws of affinity and repulsion. Hence the Inverse Sixth
is the simplest law of affinity, which satisfies the previous
condition.  In this case, if n> 8, or the mean distance
of the material particles is less than one hundred millionth,
the great superiority of cohesive force above gravitation
at the Solid Constant, and its insensible amount at one
inch distance can both be fully satisfied.
20.  To deterzmine the probable Law of Repulsion.
The Law of Affinity having now been assumed to be
the Inverse Sixth, as the simplest which agrees with the
conditions, the Law of Repulsion must be still higher, and
simplicity leads us to infer that it is also some even power.
The inverse eighth, tenth, and twelfth, have each some
claim to be the simplest. Tile first of these is the lowest
even power, after the sixth. The inverse tenth makes the
intervals equal between each pair of indices, since 10-6 =4
=6-2.  Again, the inverse twelfth has an index the
product of the two others, being the sixth power of the
law of gravity, and the duplicate of the law of affinity.
Its adoption makes the sphere of the three successive
forces more distinct, or the repulsion more marked in the
first, and the predominance of cohesion in the second
sphere, and the relation of the powers is both simpler
in itself, and with reference to calculation. On this view
the three indices r2, r8.2, al.a32 have the simplest relation
to each other, as products. The second is the triplicate of
the first, and the third a duplicate of the second. The
main features, however, of the general theory will be the
same, if a further and more exact analysis were to indicate




26               ON MATTER AND ETHER.
some other law than precisely the inverse twelfth as the
true constitution of ether.
Let us now, to fix our ideas, assume that the Ether
Constant is 10-1s or one trillionth of an inch, and the Solid
Constant ten times greater.  In this case 10" is the ethereal pressure in grains at a square inch, and 109+-, the cohesive force on a square inch, at a distance ten times
greater.  But when the distance is lessened ten times, the
increase of the particles will be 102, and the action of each
increased 10o6, so that 10"17+ will be the cohesive action at
the distance of the Ether Constant.  On this supposition,
according to the value of x, the first constant will be greater
or less; but only in a small proportion, than the Ether
Constant, and the solid constant greater than one or the
other in a nearly tenfold ratio.  WVe seem thus led naturally to the conclusion, from  the great velocity of light,
that both the Ether and Solid Constants, depending on
the actual constitution of the universe, must approach, in
their actual values, to the magnitude of the first and lowest
of those three constants, which result from  a direct comparison of the laws of force themselves.




CHAPTER III.
ON THE GENERAL FORMS OF MATTER.
21. TIlE Four Elements of the ancients, though displaced by modern chemistry, still retain in reality an
important scientific meaning.  The element of Fire finds
its counterpart in the doctrine of the imponderables, or
light, caloric, and electricity.  Air, Water, and Earth,
again, represent the three distinct forms under one or
other of which all known substances must be classed, as
gases, fluids, or solids.
On the other hand, the sixty species of unresolved substance, which are now called elements, represent evidently
an imperfect and provisional stage of chemical analysis.
They have no natural claim to be viewed as distinct and
Inconvertible kinds of substance, wholly incapable of transmutation.  They are specific distinctions, while those of
the Four Elements, rightly expounded, are generic, and
thus rank perhaps even higher in their scientific value.
Our first impressions of matter are derived from Solids,
and their resistance to the touch, or pressure of the hand.
Hence the nature of matter has often been defined by extension and solidity.  But the progress of science has
shewn the error of such a definition.  The sensation of




28             ON MATTER AND ETHER.
solidity is evidently compound, and arises from a repulsive force exercised along a well defined surface.  This
repulsion begins before actual contact, and appears to
be a rapidly decreasing power, which emanates from
the outer particles of the resisting substance.  When
it is melted or vaporized, the substance remains, but its
law of force is altored, and the sensation of solidity disappears.
Again, the impenetrability of matter, in the popular
sense, is disproved by the facts of chemical combination.
"' We may cast into potassium oxygen, atom for atom, and
again both oxygen and hydrogen in a twofold number of
atoms; and yet, with all these additions, the matter shall
become less and less in bulk, till it is not two-thirds
of its original volnme. A space which woulcl contain 2800
atoms, including 700 of potassium, is found to be filled by
430 of potassium alone." (Faraday.)  Hence the impenetrability of matter is illusive, and the term  does not correctly describe its real nature.
One of the first requisites in a theory of the constitution of matter, is to supply a general explanation of
solidity, fluidity, and gaseous expansion, the three fundamental states in one or other of which all known substances are found to exist.
22.  To ex2ccain generally the cohlesion of Solid Bodies.
Let a number of atoms, such as have been already
defined, be diffusecl through an ocean of ether. If the First
Constant be much lower than the Ether Constant, each
will condense around it, separately, an atmosphere of ether
monads, in large numbers. If slightly lower, equal, or
slightly superior, it will still attract and condense the
nearest ether monads, detaining them by a very power



CHAPTER III.                    29
ful affinity.  In either case there may be three degrees
of density.
First, let the mean distance of the material atoms be
greater than the third constant. In this case their mutual influence will depend almost wholly on the law
of universal gravitation.  They will condense gradually
towards the centres of gravity of the denser portions;
while the local pressure thus occasioned will drive away
part of the ether, and produce a repulsive action on the
less attracted portions.
Secondly, let the mean distance approach or fall below the third constant.  The affinity of the nearest atonms
will now be greater than the force of gravitation, and will
increase rapidly. There will be thus'a rapid condensation, unequally distributed, which will* tend to a granular
or mottled texture of the general mass. The more rapid
condensation of some parts, by producing vis viva, will
increase the repulsion of other portions; and while some
parts approach to a solid or fluid state, in others that
repulsion will predominate, or there will be a resemblance
to a gaseous constitution.
Thirdly, let the mean distance of the material atoms
be a small multiple of the first constant.  Their own
mutual action being double that which they exercise on
the free ether monads, the nearest will tend to approach
still nearer, till they reach the neutral distance, at which
they neither attract nor repel eachi other; or one still
smaller, where the excess of the repulsive force is equal
to the mean ethereal pressure. At this distance any number of them may assume a settled form of equilibrium, in
which the nearest distances are slightly less, but the diagonals greater, than this neutral distance.  When these




30              ON [MATTER AND ETHER.
compound atoms are wide apart, their action on each other
will not differ sensibly in its character from that of simple
atoms. But when their distance is small, or they are in
rapid rotation, their mutual action will depencl on their
shape, the number of their components, and the speed of
their rotation, and polar relations must appear.
Each of these combinations of monads, or compound
atoms, must have at least one tier or stratum  of ether
monads condensed upon it, or adhering to its outer surface. XWhen they approach each other, there will thus
be a strong repulsion at each surface; and this will tend
to produce a rotation of the atoms round some axis of
revolution.
If the atoms are distant, the cohesive force feeble, and
the vis viva great, the motion will be around the axis of
greatest moment. But when the density is greater, and
the cohesive force in consequence is large, the atoms will
be confined in the direction of the greatest moment, and
will either revolve round a longer axis, or may simply
oscillate without revolution. Many such molecules, joined
together by this mutual polarity, will have all the qualities which belong to solid bodies.
23.  To determine further the relations between the
fixed constants, in connection with the phenomena of gravitation and cohesion.
Let mn, n be the neg. logs. of the ether and solid
constants, and a, a- r, a-2-r, those of the first, second,
and third constants.  Also 1 the negative logarithm of the
cohesive limit, where the action of two atoms on the ether
belonging to each other is together equal to their mutual
gravitation.
From the velocity of light, we obtain 1017 for the ethe-;




CHAPTER III,                  31
real pressure in grains, at the distance of the ether constant.
Therefore 2rn - 17 is neg. log. for one pair of monads at
that distance, and 2n - 17 + 1.2m - 12 (a - r) the same at
the second constant.  But 6n + 7 is neg. log. for attraction
of atom  on atom at one inch, and 6n + 7 -2(a -r) th
same at the second constant.
By the definition of second constant, these are equal;
14n-   = n + 24 + 10 (a - r) or 7m = 5 (a- r) + 3n+ 12.
Again, the cohesion on a square inch, at the distance of
the solid constant, is 10~+x, being 109 in the case of steel.
But the attraction of one cubic inch on another at that
dist. has neg. log. = 7, that of atom on atom, 6n + 7, that of
1027" atoms at dist. 10-, 2n + 7;
2        4.. n-j_. (2n+7~9+Ox)4n —4: —x
is the neg. log. of the cohesive limit, or the distance where
cohesion and general gravitation are equal.
In the case of a condensed ether atmosphere,
5  3    1
I  a - -   - s (a - m) —
2  4            2
But when the first and ether constant are near together, it
is more simply,
1        1
ca - 2=r    n -4-  x.
2 2      ~4
Combining this with the former, since
5(a-r) = 3aC +2(a-  r),
we have
1                13a1
7rn=3a+n — -x+ - -   3n+ 1.2=2= 3a+4n+1 -  x,
2                         2




fe)) 2          ON MATTER AND ETHER.
a general relation between the first, the ether and solid
constants.
It results from this equation, that the solid must be
larger than the ether constant, nearly in the same ratio as
this exceeds the first constant. But the phenomena of density, in which the mechanical properties of bodies depend
so directly on their chemical nature, make it highly probable that the solid constant is only a small multiple of the
first constant. Hence the ether constant must have a value
of the same order lying between them, unless it were to be
even less than the first constant.
The supposition, then, of a vast disproportion between
the first constant or neutral distance, and the ether constant, or of a large atmosphere of condensed ether round
each atom of matter, seems excluded by the conditions;
and the other alternative established, of one, two, or three
tiers only of discrete ether monads, at finite intervals, being
grouped around them.
24.  To determine the probable relation between the first
constant, or neutral distance, and tJhe solid constant, or mean
distance qf the atoms in a body of density one, fromn the
general character of the known facts with regard to density
and pressure.
On the present theory, the first constant is that distance, below which there is a growing increase of repulsive
force, varying as the inverse twelfth power. Now the
whole ethereal pressure has been already found to be 1017
in grains per square inch.  But the weight of a column of
one square inch from the surface to the centre of the earth
is only 10l24, or six hundred thousand times less.  Hence
the condensation which it can cause, beyond that already
produced on the nearest monads under the pressure of the




CHAPTER III.                    33
free ether, must be very small.  And since platinum  is
nearly four times heavier than the mean density of the
earth, we have a presumption that it approaches to tile
maximum  density, consistent with the value of the first
constant, the mass of the earth, and the elasticity of the
free ether surrounding our planet. We may thus assume a
density = 27 as a near approach to the limit, or that which
would result, if all the monads were ranged symmetrically
at their neutral distance, diminished by the constant pressure of the ether, with no ether interposed, or chemical
structure.  It follows at once that the solid constant, or
the mean distance in a substance of the density of water, is
just about three times the neutral distance or first constant.
The lightest solid is about four times lighter than water.
It follows that the greatest linear disproportion of density,
consistent with a solid structure, is as  /108, or 4: to 1,
from cork to a density greater than of platinum, where
chemical structure ceases at the extreme limit of terrestrial compression.
But if the solid constant is only about three times the
neutral distance, and the ether constant lies between them,
the problem assumes a much more definite form.  In the
equation of condition, we may take n = a -,  that is, the
solid = J 0 x first constant, and we have 7n = 7a + 2 -x,
from Nwhich it seems to result that the ether constant is
either as small, or rather smaller, than the first constant.
For the value of x depends on the possible increase of cohesion in a symmetrical arrangement of the material monads beyond its experimental amount in steel or iron, and
unless this excess were as 1.04, which seems very unlikely,
the equation would make m> a.  On the other hand, no
allowance has been made for the probable increase in the
3




34              ON MATTER AND ETHER.
velocity of light, like that of sound, for the local compression
of the vibrating ether, which might be considerable.
It may thus be inferred, finally, that the first and ether
constants are sufficiently near to allow us to assume the
larger to be double, or less than double, the other, and the
solid constant to be only three or four times the first constant.  If we assume this last, for convenience, to be one
trillionth of an inch, and the others to be between this
limit and ten trillionths, we shall satisfy, perhaps, all
the known conditions, and render our conceptions more
definite.
25.  To exaxmine the general effects of atomic motion.int  modif.ying the cohesion.
Let a compound atom, with its attached ether monads,
be conceived to revolve round any axis. The centrifugal
force will throw out the particles near the equator, whether
of matter or ether, in proportion to the rapidity of rotation.
There will thus be an increase of repulsion to the ether in
the plane of the equator, but also an increased attraction in
the line of the axis. For the vis viva created by the repulsion at the equator must diffuse itself through the mediumn,
and occasion a greater pressure of the ether in the line of
the two poles, while the partial expansion of the radius
allows a closer approach for equilibrium.  Thus, if the
square of an octahedron were enlarged, the points must approach it, the side remaining constant.
In simple atoms, the centre has no moment of rotation,
the attached ether can have only a slight polarity, and
the axis of revolution will vary with ease. But in compound atoms, the material monads revolve round the axis,
and will be thrown out beyond their natural distance.
Such a revolving atom, in proportion to its vis viva of




CHAPTER III.                   30
rotation, will be stable, and resist any separation of its
components, or change of the axis of its rotation.
Let two such atoms revolve round parallel axes with
opposite poles on the same side. There will be repulsion
at the equator from the radial centrifugal force; but the
tangential motions will agree, and leave them neutral to
each other. But if like poles are on the same side, the
tangential motions will be opposite. The impact of the
tangential ether will make the one move round the other in
the same direction; or transfer part of the moment of
rotation from the separate atoms, and their two axes, to
the axis through their centre of gravity, midway between
them.
Again, if the axes are parallel, and similar poles on the
same side, but the line of the centres oblique to that of the
axes, the descending equator of the first will depress the
south pole of the second, and the ascending equator of the
second, so that both will tend to a new position, with an
axis of rotation at right angles to the line of the centres.
This new moment, combining with the first, will incline
the poles to a diagonal position, each towards the equator
of the other atom; and their repulsion, from the opposite
motions of the attached ether, will cause a further change,
till the axes of rotation are at right angles, not only to the
line of the centres, but also to each other.
26.  To trace the cohesive structure of solids uncder
these conditions.
Let us suppose a cubic space, filled with material monads, at a mean distance, not many times greater than the
first constant, assumed to be one trillionth of an inch. The
affinity is immensely superior to the force of general gravitation, and will create a general viscosity or mutual adhe3-2




36             ON MATTER AND ETHER.
sion of the whole mass. At the same time, the greater
part of the space will be occupied by uncomnbined ether
atoms, which will transmit on every side the general ethereal pressure. The affinity, varying as the inverse sixth
power, will draw the nearest monads of matter strongly
together, and in their approach they will rotate round each
other in some plane. They will thus become partly grouped
in revolving doublets or triplets, and the rest will continue at
first to be separate monads. The repulsive force of the rotation will tend to equalize the distances, and counteract the
direct force of mutual affinity. But it will operate in the
plane of each equator, and an opposite force of relative
attraction must be manifested in the line of every axis.
Hence the nearest particles, repelled by their equators, will
tend to combine by their poles. Their mutual affinity, in
this line, is not counteracted by centrifugal force, and their
appulse producing a new moment of rotation, they will
combine, and in combining, revolve round a new axis of
greatest moment.
The first result, then, will be to combine the material
monads into revolving planes or cycles of three, four, five,
or more monads, disposed circularly at right angles to
their axis of rotation; and the second, to combine two or
more of these revolving planes around the same axis.  But
when the vis viva, generated by these combinations, has
been mainly absorbed in permanent rotatory motions, all
the atoms will have become strongly polar to each other.
If this polarity be sufficiently powerful, it will change their
rotation from the axis of greatest to one of least moment,
which will be lengthwise, and allow the poles to retain
their closest appulse to neighbouring atoms. Thus every
compound atom, in virtue of its shape and revolution, will




CHAPTER III.                   37
have become an elementary magnet, and assume and maintain a polar and nearly fixed position with regard to all the
neighbouring atoms.  They will thus constitute a solid
and coherent structure.
Again, the phenomena of light, in transparent bodies,
and the greater amount of the ethereal pressure, compared
with cohesive force, in these and all others, prove that
ether is diffused throughout their whole texture, so that the
general external pressure penetrates the whole.  But this
is excluded from the chemical atoms, by their assumed
structure. It follows that the pressure of the free ether,
propagated through the body, is that which isolates the
chemical atoms from each other, so that at least a single
range of ether particles exists between them.  Each chemical atom will thus have its components forced closer
together by the whole amount of the ethereal pressure, and
the cohesion will be mainly through the ether particles,
interposed between them. In the densest solids the proportion of interposed ether will be the least, and in the
lightest solids the greatest; while' the cohesion, and elasticity or tenacity, will depend on the peculiarity of the
atomic structure.
27.  To explain, by the present hypothess, the liuefacction of solicds.
Sir H. Davy remarked, long ago: " It seems possible
to account for all the phenomena of heat, if it be supposed
that, in solids, the particles are in a constant state of vibration, those of the hottest bodies moving with the greatest
velocity; and that in liquids and elastic fluids, besides the
vibratory motion, the particles move round their own axes
with different velocities."  The more recent discoveries on
the mechanical equivalence of heat confirm this general




38             ON MATTER AND ETHER.
suggestion, and prove the correctness of Bacon's early conclusion, that heat is only a form or effect of atomic
motion.
Let us suppose that vibrations, propagated through the
ether, produce oscillations in the compound solid atoms,
while retained by polarity in their own places, around their
mean position. This increase of motion will produce an increase of repulsion, by which the atoms will recede from each
other, and the body expand.  By this same expansion, the
polar force, which recalls them to their mean position, will
be diminished. When the expansion and oscillation have
reached a certain limit, the polarity will be too weak to
destroy the angular velocity, and the particle will continue to revolve to another polar position.  This revolution, at first, will be unequal and intermittent.  But if
the momentum, or collective vis viva increases, it will become nearly uniform. The former case will be one of
viscous, and the other of more complete fluidity. Each
revolution must be very rapid, from the greatness of the
cohesive force at these small distances, and the attraction
of a particle in any direction will be the mean of its values
in every angular position. This equality of cohesion and
repulsion in all directions constitutes the definition of a
perfect fluid.
28.  To explain the evaporation qf fluids.
The particles of fluids must be in a state of rapid revolution round their own centres.  The density will then be
determined by the balance between affinity and external
pressure on one side, and centrifugal force and ethereal
repulsion on the other. A rise of temperature will increase
the velocity, and with it, the centrifugal force; and part
of the attached ether, being thus set free, will increase the




CHAPTER III.                    39
repulsion.  The fluid will therefore expand, and the particles recede.
Up to a certain limit, the cohesive force, or the excess
of the central attraction over central repulsion, will increase by distance, and a certain amount of vis viva, or
sensible motion, is absorbed by the increase of mean distance.  Beyond this limit an increase of centrifugal force
diminishes the cohesion. The repellent will then prevail
over the attractive forces, or the cohesion and pressure,
and the body will begin to pass into the gaseous form.
Let r be the radius of each revolving atom, measured
from its centre of gravity to its outmost component atoms,
and s the distance of their outmost atoms from each other,
when they approach nearest in their revolution. The cohesive force will result mainly from the mutual action of
these outer atoms, during a part of their rapid rotation,
and the excess of their attraction over their repulsion. In
their equilibrium, these are equal, and for maximum cohesion 1.2x-3= 6.-7 or x=  =2 = 112246, or the mean distance
is increased in the ratio of r + ~s r +~ 56123s, or nearly
as 2 + s: 2r + s + ss.  Beyond this limit, the cohesive
force will only be lessened by the further expansion, and
the liquid must therefore assume the gaseous form.
The expansion of water, from its maximum density
to its boiling point, is nearly 1'403061, or in linear density 1'013919.  Hence, by the formula, 2r + s =  8'8s, and
r = 3'9s nearly. It would result, from this explication, that
the distance of the nearest points of the revolving atoms is
about 4 of their radius, or one eighth of their diameter;
though, of course, many other elements would have to be
included in a more exact solution, which must depend on a




40              ON MATTER AND ETHER.
correct view of the various chemical elements, and the mode
of combination of the aqueous atoms.
29.  To explain generally a fourth condition of matter,
which is neither solid, liquid, nor gaseous, but igneous or
ethereal.
A gas is defined by its elasticity, or its constant tendency to expand, when not restrained by external pressure.
But the consequences of this definition at the upper limit of
the atmosphere have never been clearly traced, because
the fundamental laws of matter and ether have been unklnown.
When we rise from the earth, the density of air decreases, heat is absorbed, the temperaturle becomes lower,
and the elasticity grows more feeble.  The limit of these
changes must be a state in which elasticity ceases, latent
heat is.very great, and the temperature proportionally
low.  These facts admit an easy interpretation on the present theory.
In a gas under pressure, the centrifugal force, from the
relative motions of the separate chemical atoms, with the
repulsion of the ether, exceeds the cohesive force.  If the
pressure be withdrawn, the particles must recede further,
and in receding, vis vivac is absorbed, and their motion
must become feebler.  The velocity being the same, the
centrifugal force diminishes inversely as the mean distance,
while by the same expansion, the velocity itself must be
lessened, till it almost disappears.  The motion of translation, first, and then of rotation, will gradually  cease.
Thus the sensible temperature, which is measured by
this motion, will decline, and approach *to an absolute
zero, but the latent heat will increase, and reach its
nmaximumr.  For by the separation of the particles, and




CHAPTER III.                   41
their approach to a state of rest, each will exercise its
attracting and condensing power to the utmost on the
surrounding ether, extending to those distances where
gravitation begins to be stronger than cohesive affinity.
Such a state of matter cannot be called gaseous, since
all the defining properties of a gas have disappeared.
Elasticity and expansiveness are replaced by inelastic repose. The want of intestine motion, either of translation or rotation, will make it resemble solids rather than
liquids, while in density it occupies the other extreme;
and being saturated with ether, it will approach to the
properties of the free ether which it adjoins.
There will thus, according to the present theory of
the laws of matter, be more truth than has latterly been
recognized in the old arrangement of the four elements,
which placed a fourth region of fire above the solid, liquid,
and gaseous constituents of our globe. In fact, above the
region where the air, though greatly rarified, is still elastic,
there must be a still higher stratum where elasticity has
wholly ceased, and where the particles of matter, being
very widely separated, condense around them the largest
amount of ether. All sensible heat, in the collision or
oscillation of neighbouring atoms of matter, will thus have
disappeared; but latent heat, in the quantity of condensed
ether, or repulsive force ready to be developed on the renewed approach of the atoms, will have reached its maximum; and may be capable of producing the most splendid
igneous phenomena, like the northern lights, or tropical
thunderstorms.
30.  To explain the mutuztal relations of the solid, liquid,
gaseous anad igneous forms of matter.
The laws of affinity and repulsion imply a first con



42              ON MATTER AND ETHER.
stant, or minimum distance, at which two atoms of matter,
each charged with one of ether, will be neutral to each
other, repelling at less, and attracting each other at greater
distances.  Chemical or compound atoms are to be conceived as made up of a definite number of these simple
atoms, arranged regularly in planes or cycles, so as to exercise polarity at their sides and angles.  The solid state of
bodies is that in which these compound atoms are attached
to each other in permanent positions by their polar qualities, so that a slight increase of distance generates a powerful attractive force, and a slight decrease by pressure a still
more powerful force of repulsion. The liquicl state is that
in which these compound atoms revolve on axes, so that
their polarity and fixity of position disappear, and they are
able to move amongst each other, while they still continue
within the cohesive limit, or their attraction is increased by
a slight increase of their mean distance. The gaseous state
is when they pass by expansion beyond this limit, and the
attraction being lessened by increase of distance, tend
continually to separate more widely, and are only restrained within moderate distance by external pressure.
The fourth, or igneous state, is that in which gaseous elasticity has ceased through further increase of distance, and the
consequent absorption of vis viva, and in which, the solid
atoms, having been separated into their planes, and even
these, perhaps, into their simple atoms, these last are distributed almost uniformly by the repulsive force of the
ether which they have separately condensed around them.
31. RESULTING DEFINITIONS.
Mlonads are the self-repulsive particles of ether, diffused
through all space.
Atoms are the dual particles of matter and ether com



CHAPTER III.                    43
bined inseparably, which constitute the first or ultimate
elements of all ponderable substance. They combine in
their mutual action the three different laws of general
gravitation, cohesive affinity, and ethereal repulsion.
The First Constant, or neutral distance, is that at which
two such atoms neither attract nor repel each other, or
rather, attract only with the infinitesimal force of general
gravitation.
Conpound, ch7emical, or plural atoms, are the ultimate
elements on which the constitution of every specific kind
of gas, solid, or liquid depends, and must be conceived to
consist of a definite number of simple atoms, in some simple or compound arrangement.
Sen sible heat is the vis viva of the slight oscillations of
solid or liquid atoms, or of the motions of the particles of
gas amongst themselves.
HIeat of zJudity is the vis viva of the motion of rotation
in the particles of fluids.
Heat of vaporization is the vis, viva absorbed in gases,
by the separation of their elements to a wider distance,
beyond their mean distance in their liquid form.
BFeat of clhemical combination is the vis viva developed
by the new and closer relation of mutual distance, into
which the components of compound atoms are brought
by their union. Assuming the arrangements to be known
before and after that union, its amount will be capable of
exact calculation, the laws of affinity and repulsion being
also known.
Light consists of vibrations or undulations, transverse to the axis of the rays, propagated through the free
ether of space, and transmissible, in some cases, through
the substance of solids and liquids either through inter



44             ON MATTER AND ETHER.
stices filled with free ether, or the combined ether of the
particles themselves.
Electricity consists in the increase or decrease of the
mean vis viva of ethereal repulsion between surfaces of
material substances, arising from some change or special
modification, of those surfaces, with reference to their
charge of attached or combined ether.




CHAPTER  IV.
ON THE IGNEOUS FORM OF MATTER.
32.  To explain t/he phenomena of the nuclei and tails
of Comets.'" There is beyond question," Sir J. Herschel remarks,
"some profound secret and mystery of nature concerned in
these phenomena. Perhaps it is not too much to hope that
future observation, borrowing every aid from rational speculation, grounded on the progress of physical science, will
ere long enable us to penetrate this mystery; and to decide
whether it is really matter in the ordinary acceptation,
which is projected from their heads with such extravagant
velocity, and directed from the sun as its point of avoidance." He then remarks, on the tail of the comet of 1843,
which was brandished unbroken in two hours through an
angle of ninety degrees, and still reached to the earth's
orbit; that " it is utterly incredible that it is one and the
same material object, and that the notion of a negative
shadow would best explain it; while still there are many
other phenomena, as the issuing of the streamers from the
nucleus, which link themselves just as irresistibly with our
ordinary notions of matter."




46              ON MATTER AND ETHER.
In the Principia, Sir I. Newton argues that the tails of
comets are rarefied smoke or vapour, which ascends from
the sun, as smoke ascends in a chimney. But how it
should ascend, unless the medium were much denser, instead of rarer than itself, or how it should acquire such a
vast velocity, he does not attempt to explain. But he
quotes the opinion of Kepler, that the rays of light might
carry away the particles of matter along with them; which,
after all, is probably the nearest approach to the truth
which it is possible to make, while the constitution of
matter and ether is unexplained. Let us now see whether
light is not thrown on this subject, by tracing; on the
present theory, the consequences of the igneous form of
matter.
The mass of comets, it appears from many signs, is
very small in proportion to their size. The matter they
contain must then be highly rarefied. The idea of Newton, that " they are solid, compact, fixed, and durable, like
the bodies of the planets," has been disproved by later and
closer observation.  Their density, it seems, is far less
than that of air at the earth's surface. They must then,
in their aphelia, be mainly in the igneous form, their particles widely separated, clothed with a full charge of ether,
feebly united by gravitation, with a very slight amount of
cohesive power.
When they return towards the sun, gravitation will
ensure their near approach to a spherical form, and a process of gradual condensation. In those which are large or
dense, tilis contraction will be more rapid and unequal,
from the development of affinity also. As soon as this is
called largely into play, it will cause intestine motion,
and the vis viva produced will expand the less attracted




CHAPTER IV.                    47
parts, and retard their condensation.  The comet will thus
consist of slightly coherent nuclei, gaseous envelopes of
each little nucleus, and a common igneous envelope of the
whole; or else of gaseous spaces, and the igneous envelope
alone. The uniform arrangement, and partial coherency of
the envelope, will maintain the gaseous elasticity by a constant pressure.  The longer the attraction of the parts has
been undisturbed, the more will the nuclei enlarge, and
the elastic force of the gaseous atmosphere will be more
developed.
Such a body, moving uniformly through a sea of free
ether, will assume by its resistance the form of a slightly
prolate spheroid, and the nuclei, by the same resistance,
will of course be found in the anterior part of the whole
moving figure.
33. Besides the atmosphere of the sun, which revolves
along with it, the space as far as the earth's orbit is more
or less charged with matter in a very rare state, by which
the zodiacal light is occasioned.  This matter also must
of necessity be in the igneous form. Each shell of it is
drawn inward by the sun's attraction, and must produce a
pressure on the parts within, and thus its density towards
the sun must increase by a similar law to that of the
gaseous atmosphere of the earth.  When the comet approaches the sun, the solar attraction, the heating power
of the solar rays, and the resistance of this igneous atmosphere, will all increase together, and the following results must ensue.
First, the increased velocity of the comet, the sun's
attraction, and the inertia of the igneous atmosphere, will
cause together an increased pressure on the igneous envelope.  So far as this results from the motion, it will be in




48              ON MATTER AND ETHER.
the line of the comet's path, but so far as it depends on
the two other causes, in the line of the radius vector. The
inner parts will be condensed under this pressure, with a
great increase of the cohesive action, by which the inner
strata of the igneous envelope will be condensed into gas,
and some of the nuclei resolved into it also. Thus we
shall have a nucleus or nuclei in the anterior, refracting
light; a transparent gaseous portion, and an igneous envelope, lessened in amount, and pressing strongly upon the
gaseous parts within.
Let us now compare the description which Sir J. Herschel has given (Astr. ~ 560). "That the luminous part
of a comet is something in the nature of a smoke, fog, or
cloud, suspended in a transparent atmosphere, is evident
from a fact often noticed-that the portion of the tail:which comes up and surrounds the head, is yet separated
from it by an interval less luminous, as if sustained and
kept off from contact by a transparent stratum. This and
other facts appear to indicate that the structure of a comet
must be that of a hollow envelope, of a parabolic form,
enclosing near its vertex the nucleus or head. This will
account for the apparent division of the tail into two lateral
branches, the envelope being oblique to the line of sight
at its borders, and therefore a greater depth of illuminated
matter being there exposed to the eye."'l'lThe nucleus,
thus described, must be solid or liquid portions, like smoke
or fog, not fully resolved into elastic, transparent vapour.
The middle or transparent part must be in the state of gas,
and the conic and parabolic envelope are the parts of the
comet in the igneous form.
34. The formation of the tail is simply explained on
the present theory.




CHAPTER IV.                    49
Let a, r be the perihelion distance, and actual distance
of the comet from the sun.  Then its velocity in its orbit,
supposed parabolic, is,   compared with that of the
earth, or 96300 miles per hour, and 263 per second, at the
earth's distance. Again, its velocity towards the sun is
J2r - 2a, compared with the earth's velocity of 68100
miles an hour. Thus, when the comet is at* the earth's
distance, and its perihelion distance less than one half, it
must displace, every hour, a column of the sun's igneous
atmosphere, more than 68000 miles in depth, and its head
will move into a region of greater ethereal density.  The
front will be more compressed by this igneous atmosphere,
and will contract in size.  The hinder parts, repelled by
the gaseous elasticity, less attracted by the sun, and less
compressed by the external ether, will be left behind, less
influenced by the comet's own attraction, and therefore
must expand. The hinder part of the gaseous atmosphere,
by this expansion, will reassume the igneous form.  The
increased pressure in front, by the motion which dips into
the igneous atmosphere of the sun, must cause reaction in
the neighbouring columns, as when a stone falls into still
water, and this will sweep back the lightly adhering ether
near the comet's head, and thrust the expanding hinder
part into the line opposite to the sun. Hence a tail will
be developed, lying between a line drawn from the sun to
the head of the comet, and the line of the comet's motion;
but having the former direction for its tangent, where it
joins the head, because the ethereal repulsion must act in
that line with the greatest energy. The velocity with
which the matter of the tail is thus repelled at first will
4




50             ON MATTER AND ETHER.
be less than that of light, which depends on the total elasticity of the ether, but will bear to it some definite proportion, determined by the relative number of the particles
of matter, and those of free ether. Thus the immense velocity with which the tails are produced seems to be clearly
and fully explained.
The approach to the sun is most rapid at 900 from
perihelion, but the velocity in the orbit is greatest at
the perihelion passage.  Now the development of the tail,
except so far as it depends on the internal structure, is
determined by these two causes, and its maximum increase
will naturally and usually be somewhere between them.
Accordingly, Halley's comet made its perihelion passage
Nov. 16, 1835, was 900 from it about 62 days earlier or
Sept. 15, and its tail had the greatest apparent length
Oct. 15, or exactly half way between these two extremes.
At the first it had hardly begun to be formed, and at the
perihelion it had disappeared.  But in this case the latus
rectum was greater than the diameter of the earth's orbit,
and the velocity to the sun was decreasing when it entered
the sphere of the earth.  So far as the generation of the
tail depends on the heating and exciting power of the sun,
it will be greatest just before and after the perihelion; and
accordingly, in other cases, the development of the tail is
then the most striking. This was eminently true of the
comet of 1843, which was so remarkable for the smallness
of its perihelion distance.
35. The streamers from the head of Halley's comet,
in 1835, are another remarkable phenomenon, which is
simply explained by the present theory.
"On Oct. 2 the nucleus, which had been faint and
small, was observed suddenly to have become much brighter,




CHAPTER IV.                    51
and to be throwing out a streamer or jet of light from the
part turned towards the sun. This ejection, after ceasing
awhile, was resumed on the Sth with much greater violence, and continued, with occasional intermittence, so long
as the tail itself was visible. At one time the jet was
single, and confined within narrow limits of divergence.
At others, it presented a fan-shaped, or swallow-tailed form,
like a gas flame from a flattened orifice; and at others,
two, three, or even more jets were darted forth in different
directions.  The direction of the principal jet was observed
to oscillate to and fro on either side of a line to the sun,
in the manner of a compass needle, the change being conspicuous even from hour to hour.  These jets, very bright
at their point of emanation, faded rapidly away, and became diffused, as they expanded into the coma; at the
same time curving backward, as streams of steam or smoke
would do, if thrown out from narrow orifices in opposition
to a powerful wind, against which they were unable to
make way, and ultimately yielding to its force, so as to be
drifted back, and confounded in a vaporous train, following the general direction of the current." The conclusions
drawn by Sir J. Herschel are these: " That the matter of
the nucleus is powerfully excited and dilated into a vaporous state by the action of the sun's rays, escaping at
the points of least resistance.  That this process takes
place chiefly in the part turned towards the sun, the vapour escaping chiefly in that direction. That it is prevented from proceeding by some force directed from the
sun, drifting it back, and carrying it out to vast distances
beyond the nucleus. That this force acts unequally on the
materials of the comet, the greater part remaining unvaporized, and a considerable part of the vapour produced
4-2




52             ON MATTER AND ETHER.
remaining in the neighbourhood, to form the head and
coma."  To these remarks it may be added that the bulk
of comets contracts greatly in approaching the sun, which
Mi. Valz ascribes to increased ethereal pressure; but Sir
J. Herschel rejects that view, as requiring a solid envelope,
and refers it to vaporization, by which a great part is rendered invisible.
Now it has been shewn that, when the comet approaches the sun within the earth's sphere, the increasing
density of the sun's unattached igneous atmosphere must
press with greater force upon the comet's igneous envelope.
Hience will follow a contraction of the anterior part, where
the nucleus is contained, and increasing elasticity of the
gaseous envelope, which will also increase in quantity, by
the conversion both of igneous and diffused liquid portions into elastic vapour. Thus both the causes, suggested
by M. Valz and Sir J. Herschel, and not one only, will be
at work, and will conspire to produce a contraction of the
nucleus, while the former alone will alter the apparent size
of the igneous envelope. The objection of Sir J. Herschel
to the solution of 3[i. Valz, that the exterior of the comet
would require to be like a skin or bag, impervious to
the compression, is at once removed by a reference to
the laws of the igneous form  of matter, which really
approaches to this very character. For matter in this
state, though immensely rare, instead of being repulsive,
lmust be slightly coherent, while it also transmits ethereal
pressure.
When the igneous envelope has been thinned by this
compression, like a soap-bubble by the resistance of the
air, as well as by partial abrasion, and conversion into gas
on its inner surface, while the contained gas has grown




CHAPTER IV.                    53
more elastic by solar heat, and increased molecular attractions, the pressure in some parts of its surface may overcome the resistance, and the pent-up gas will then escape
through the orifice in the envelope, like steam from the
boiler of an engine.
As soon as it escapes, which must be on the side towards the sun or the comet's way, it will expand rapidly
by its own latent heat or gaseous repulsion, and one part
will assume the igneous, and another the minutely liquid
form, like steam when it cools, and will charge itself with
ether from the surrounding medium.  Being thus etherealized, and in the igneous form, it will be driven away from
the sun by a double power; the reaction of its own impact
on a highly elastic igneous medium, and the general tendency to diffuse itself in agreement with the laws of that
medium.  For the excess of matter in any column must
cause an excess of ethereal density, which must then diffuse itself in the direction of least resistance, or in the
direction away from the sun.
36. The formation of the tail, on receding from the
sun, admits of a similar explanation.
The gaseous state of the comet will have reached its
height, either at or soon after the perihelion passage, and
also the pressure of the medium itself. When this pressure
begins to diminish, as well as the sun's attraction, the
matter of the comet will tend to expand in all directions.
Towards the sun, however, it will be strongly restrained
by the pressure, and hence it must actually expand most
in the line of least resistance, or away from the sun. The
effects, then, will have a close resemblance to those on the
approach. As the comet recedes more and more, the pressure lessens on all sides, and the expansion will become




54             ON MATTER AND ETHER.
greater, till the comet disappears from view through its
gradual loss of illuminating power.
Thus all the main phenomena of cometary motion and
development, which have excited so deep an interest of
late years, find an easy and complete general solution, in
the present theory, by a reference to the necessary properties of matter in its igneous form.
37. The separation of Biela's comet admits, in like
manner, of an easy and simple explanation.
Let us suppose the nucleus, or denser part of the
comet, to have two centres of maximum density, in the
neighbourhood of which the cohesive force has begun to
be most developed. The approach to the sun, increasing
the temperature and the external pressure, will accelerate
this action, and the pressure of the gaseous envelope will
force the parts of the two condensing nuclei nearer together. The vis viva thus generated, will react on the
gaseous portion, especially in the line which joins them,
and by its reaction repel them further from each other.
If they lie at right angles to the head of the comet, neither
of them will be strongly repelled by the front pressure
where it is a maximum, and they will swell out the sides
of the coma. But the gaseous elasticity, in the line of
their junction, being lessened by this lateral separation,
will no longer neutralize the strong pressure of the external
medium on the opposite part of the igneous envelope. It
will thus be forced inward, like an army pierced by the
irruption of a strong column in the centre, and a new lateral
force will thus be created, which will complete the separation. But before the equilibrium of each part can be
restored, it is quite conceivable that strong electrical relations may exist between the two separated portions, so as




CHAPTER IV.                    55
to explain those alternations of size and brightness in the
two companion comets, which added to the singular character of the phenomenon.
All the explanations now offered grow by necessary
consequence out of the fundamental assumptions; that, besides ponderable matter, there exists throughout space a
self-repulsive ether; that the attraction of matter for ether
follows a higher law than the inverse square, and probably
as high as the inverse sixth, so that every atom of matter
is combined inseparably with one of ether, and that the
self-repulsion of ether follows a still higher law. From
these data it will follow at once, that matter, besides a
solid, liquid, and gaseous, must also be capable of assuming
a fourth or igneous form; and that the properties of this
form are such as to account for the singular variety of phenomena connected with the transmutations of comets on
their approach to the sun, and their return from it again,
which have caused so much natural wonder and perplexity
to those astronomers by whom they have been observed,
and of which the comet of this present year seems to
furnish a new and striking instance,




CHAPTER V.
THE NATURE AND PROPERTIES OF LIGIT.
38. THE Undulatory Theory of Light, maintained by
Huyghens, and since revived and extended by Young,
3Malus, Fresnel, and others, has now the general assent of
men of science. By its help a large variety of complicated
phenomena have received a clear explanation.  Still, the
vagueness of the usual conceptions of the nature of the
luminous ether, and of its relations to common matter, have
left many parts of the theory in a state of great obscurity,
and offer large room for further scientific progress.
The present view of matter and ether will naturally include, as one of its immediate consequences, the whole
theory of the undulations of light. At the same time, by
supplying a distinct and well-defined conception of the
laws of ether, in relation to common matter, it will, if
a true interpretation of nature, provide a key to many
outstanding difficulties, and solve many problems, which,
without its aid, would be perplexing and obscure. The
simplest order is to begin with the facts already explained,




CHAPTER V.                     57
and to shew their connection with the theory, and then
to pass on to others, which still need an explanation.
39.  The postulates of the common theory have been
clearly stated by Sir J. Herschel (Enc. Metr.), and they all
flow naturally from the hypothesis of the present work.
(1)  An excessively rare and elastic ether pervades all
space.
This results at once from the assumed law of repulsive
force in the ether.  A finite number of such monads, confined to a given space, will arrange themselves so that the
collective repulsion shall be a minimulm, or very nearly at
equal distances, though slightly condensed at the surface
and edges, and the whole must have a density very nearly
uniform.  For if any portion were denser than the rest, it
would expand by the excess of the repulsive force, till it
reached, as nearly as possible, a uniform arrangement.  If
the density wmere solely due to the nearest particles, it
would be strictly uniform.  But since the total action of
the central particles on those not adjoining is greater than
for those near the surface, there will be a very slight difference in their density. For all sensible distances the distribution will be sensibly uniform, and the action like that
of a continuous and homogeneous fluid.
(2)  It gpervades all material bodies, and occzupies the
intervals between their molecules.
This statement, on the present hypothesis, would be
strictly true, if the mean distance of the compound atoms
of bodies were much greater than the first constant, and
the distance of the free ether in space.  The surrounding
ether would then fill all the interstices of the solid or fluid
atoms. It seems to follow, however, from the conditions
already examined, and the phenomena of chemistry, that




r,"i8          ON MATTER AND ETHER.
the mean distance of the solid atoms is very little greater
than that of the free ether in space. In this case very
little free or unattached ether can commonly enter between
the pores or interstices of the heavier solid bodies. But, on
the other hand, the theory teaches that every atom of matter
is combined inseparably with one of ether, and these retain
unaltered their own self-repulsive power, though modified
in its effects by its union with the matter, to which it is
thus attached.  Hence ethereal vibrations must of course
be propagated through the whole extent of these bodies,
though greatly modified by the presence of the matter,
and the special atomic arrangement.
(3)  Either by passing between them, or by its extreme
rarity, it offers no resistance to the motion of the earth,
planets, and comets, appreciable by the most delicate observations.
This statement has now to be modified by the discovery of the retardation of Eneke's Comet, and some other
similar phenomena. The calculated amount is such that,
if the comet were to move with tile earth's velocity in the
earth's orbit, its motion would be extinguished by the resistance in about three millions of days.  Supposing, now,
its size to be that of the earth, and its mass 40000 times
less, or density one-tenth that of air at the surface, then
the same cause would extinguish the motion of the earth in
300 millions of years. But the earth's motion must probably be communicated to the ambient ether by frequent
revolutions, nearly in the same time. Hence the relative
velocity may be lessened ten or a hundred times, and the
resistance in the duplicate proportion.  Still, the fact of a
sensible resistance in the case of some comets opens a wide
field for curious speculation.




CHAPTER V.                     59
(4)  T. he molecules are capable of being set in mnotion by
the particles of matter, and of communicating motion to the
particles which are adjacent.
This property results directly from the assumed laws.
It must equally follow that this action is insensible at all
sensible distances. In the illustrative case proposed, the
action of ether on matter is less than that of an atom of
matter on matter at one inch distance, and this latter force
is insensible.
(5)  It is less elastic in refracting bodies.
This conclusion is drawn from the smaller velocity of
the waves of light in denser substances.  And it results at
once from the present hypothesis. For the velocity of
restoration, after a disturbance, or the modulus of elasticity,
must be diminished by the whole cohesive power of the
matter combined with the ether, since the two forces from
the same centres have opposite signs, and the repulsion of
the ether centres is lessened by all the attractive power of
the matter with which they are combined.
(6)  The frequency of the pulses, or number of impulses
made on our nerves in a given time, determines the colour of
the light, and the amplitude of the excursions, its brightness
or intensity.
This statement, it will probably be found, requires to
be partially modified. The intensity of light seems to be
more truly defined by the vis viva of the vibrating pulse
which reaches or enters the eye, than by the amplitude of
vibration in a single line of particles. From  this larger
definition it would equally follow that, with a single row
of particles, a double excursion would imply a fourfold
intensity. But the corrected view, besides its greater
simplicity, removes a difficulty which would otherwise




60             ON MATTER AND ETHER.
arise, from the difference between common light, and light
elliptically polarized.
Again, the length of the wave determines the refrangibility, but it is still an open question, if not decided by
this time in the negative, whether this property and the
colour are inseparable.  The origin of the sensation of
colour seems to be physiological, even more than physical,
and is not easy to explain, so as not to desert wholly the
natural analogy with the musical notes, or waves of sound.
With these slight reserves, all the main postulates in the
common undulatory theory of light result simply from the
view of matter and ether, and the laws of their mutual
action, here proposed.
40.  To explain the Reflection and 2Bfraction of Light.
In Airy's Tracts, or Herschel's Treatise, the truth of
the two fundamental laws, for reflection and refraction, is
shewn to depend on two principles. First, that the velocity of a wave is constant in the same medium, and
is diminished in one of greater density, in the ratio of
the index of refraction. Secondly, that the face of the
wave must be reached in the same time by parallel
filaments or pencils of the luminous wave, since in other
directions the vibrations are extinguished by their mutual
interference.
The just claim to be made on any special hypothesis of
the mode of action, is that it shall supply an adequate
cause for the decrease of velocity in the denser medium,
and one consistent with the great variety of refracting
power in bodies of different composition.
Now the equilibrium of any solid or fluid, on the present view, must depend on a balance between the pressure
of the external ether, and the attraction of the particles of




CHAPTER V.                     61
matter joined with those of ether, on the one side, and the
centrifugal force, or vis viva of atomic motion, and the
repulsion of the combined ether particles, on the other. It
is plain that the elasticity will thus be diminished, beyond
that of free ether, by the counteracting force of all the
attraction developed by the nearer approach of the matter
to the neighbouring ether.  On the other hand, it will be
increased by the greater development of repulsive energy
arising from  the smaller distance of the combined ether
particles from each other, compared with that of the free
ether in space. The effect will be to diminish the elasticity of the recoil, but most of all for the short waves, of
which the recoil is most rapid, since it is the increase of
compression which alone can develop a larger ratio of repulsive or elastic power.
41. To account for the Dispersion of Light.
Sounds of different pitch are conveyed through air
with the same velocity, and the notes of a piece of music,
from any distance, reach the ear in their proper order.
But the velocity of light is found to vary, in passing
through gases,. fluids and solids, with the length of the
wave, since the violet are more refracted than the red rays.
Sir J. Herschel remarks on this difficulty:'" Neither the
corpuscular, nor undulatory, nor any other system yet
devised, will furnish that complete explanation of the
phenomena of light which is desirable.  Certain admissions must be made at every step, as to modes of mechanical action, when we are in total ignorance of the acting
forees; and we are called on, when reasoning fails, occasionally for an exercise of faith."
Prof. Airy makes a similar admission of the difficulty
which presses here on the theory, and offers a conjectural




62             ON MATTER AND ETHER.
explanation: "Part of the velocity of sound depends on
the altered elasticity of the air by the deyelopment of heat
from its compression. If the heat required time for its
development, the quantity of it would depend on the time
the particles remained in nearly the same relative state,
that is, on the time of vibration. If we suppose some
cause, which is put in motion by the vibration of the particles, to affect in a similar manner the elasticity of the
medium of light, and the degree of its development to
depend on time, we shall have a sufficient explanation of
the unequal refrangibility of the differently coloured rays."
Another solution has been proposed by Cauchy and
others, from the hypothesis of finite intervals between the
ether particles. The conclusion drawn from analysis is,
that " a variation in the velocity of light is produced by a
variation in the length of the wave, provided the interval
between the molecules of ether bears a sensible ratio to the
length of the undulation."  This appears to be accepted
by Dr Whewell, in the History of the Inductive Sciences,
as a probable and adequate explanation.
Both of these solutions still involve serious difficulties.
And first, it is not easy to see how the condition required
by Cauchy's formula  can be fulfilled. The length of a
violet wave is one sixty thousandth of an inch. But
Frauenhofer has ruled lines on glass, only double that
distance apart, and Dr Wollaston has formed a platinum
wire of the same diameter, while gold may be beaten to a
thinness only one-fifth the length of a violet wave. Hence,
on this ground alone, the distance of metallic atoms must
be considerably less than the length of the shortest waves
of light. But the previous inquiry would lead us to the
conclusion that the distance both of material atoms, <and of




CHAPTER V.                    63
the monads of free ether, is much less than one billionth,
and may probably not be much higher than one trillionth
of an inch. Hence the disproportion between this distance,
and the length of the waves of light, is in all probability
far too great to admit of the solution Cauchy has proposed,
and others have accepted, for the unequal refrangibility of
different waves.
A second objection seems equally decisive. For on
this view the dispersion should increase, as the medium
departs more widely from continuity. But the ether must
be most condensed in solid bodies, more rare in the atmosphere, and most of all in vacuo. Hence, by the hypothesis, it would seem to follow that the dispersion must
be least in dense bodies, and greatest in vacuo, which is
just the reverse of the real truth.
The other solution is open to an objection of hardly
less weight. The time of vibration, in the case of sound,
is immensely greater, and a more subtle element is present
than the vibrating particles themselves; and yet there is
no sensible difference in the velocity of long and short
waves. Now both these differences would seem to make
a variation more natural in the case of sound, where it
does not exist, than in that of light, where it is so conspicuous. The first objection may be parried, by supposing the unknown cause, compared to the latent heat of
the air, to need only a very short time for its development.
But the second can only be removed, by supposing the
dispersion to be due, not to a more subtile element, as the
latent heat which accelerates sound, but to one less subtile
than the vibrating medium, or in other words, to the
ponderable matter. But the view then resolves itself into
the early suggestion of Dr Young, that it depends on the




64             ON MATTER AND ETHER.
reaction of the matter on the condensed ether, by which its
elasticity may become a function of the time. This idea
Sir J. Herschel seems to have dismissed rather too lightly.
However vague such an explanation must be, in the absence of a definite law for the relation between matter and
ether, it must seem highly probable on almost any reasonable view of that relation. On the present hypothesis,
the truth of this early suggestion of that eminent philosopher will be fully confirmed.
42. Let us first consider, on this view, what will be
the general condition of the ether, ti vacuo, in gases, in
liquids, and in transparent and opaque solids. In vacuo,
it will be free, equally diffused, and intensely self-repulsive, the amount of ethereal pressure on the square inch
being not much less than eighteen billions of pounds. In
gases, it will clearly approach to its condition in vacuo,
since only about one thousandth of the space is occupied
by the material particles, and all the rest must be filled
up with the ambient ether, slightly condensed by the
cohesive affinity of the gaseous particles, while the simple
component atoms of matter are also each combined with
one of ether. In liquids, the proportion of free ether must
be very much less. It results from the previous inquiry
that the size of the compound material atoms can exceed,
only in a slight degree, the intervals of the free ether in
space. But since each atom of the fluid is in a state of
revolution, and around its axis of greatest moment, each
requires an atomic space equal to the-cube of the mean
distance of the particles or compound atoms, and this must
exceed slightly their greatest length or breadth.  The
solid space, in the case of regular cubes, will be only  V/3




CHAPTER. 
or less than one-fifth of the whole, and still less for flat or
oblong figures. All the rest of the space must be occupied
by condensed ether, of which patt may be attached to
the fluid atoms, and revolve with them, and the rest fill
up the interstices by the force of the immense ethereal
pressure.
The state of the. ether, in solids, and its relative
amount, must plainly depend on the arrangement of the
monads that compose the cherhical atoms, and on the
arrangement of those atoms amongst themselves. In other
words, it will, depend on their chemical composition, and
also on the presence or absence, or on the peculiar kind,
of crystallization.  It is easy to conceive that, in the case
of the more solid atoms, which have most cohesive force
and the greatest density, there may be only single lines
of attached ether, by which ethereal pulses can be directly
conveyed across sensible distances. On the other hand,
when the atoms have an angular or rhomboidal arrangement, there will as plainly be lines or paths of communication filled with ether by the ambient pressure, throughout the whole mass.  The former will represent the class
of opaque, the latter of transparent solids,
43. The velocity of a wave or pulse of ether, in travelling through a liquid or transparent solid, will plainly
be affected by two causes. First, its path must wind
round the material atoms, and since these, in their greatest
length, nearly touch one another, there must in every case
be a very sensible retardation, due to this cause alone.
Thus, if we assume the atoms of water to be cubes, and
the path of each ray so deflected as to move in circular
arcs, of which the depth is to the chord as the side of a
squlare to its diagonal, the path will be increased, or the




66             ON MATTER AND ETHER.
velocity lessened in the ratio of 1'3332 to one, which is
very nearly the known refracting index.
Again, the undulations of light vary from 458 to 727
billions in a second.  Supposing these to be transverse to
the path of the ray, the view which results from the phenomena of polarization, then such excursion must be from
the central path of least solid resistance towards the sides
of the path, where it is shut in by the solid or fluid atoms.
The ether will there be more condensed, in consequence of
the cohesive attraction, and a motion through an equal
space will therefore develop a greater resisting or repulsive
force. And tlhis difference will naturally increase, in proportion to the weight or inertia of the material atoms,
though it must depend also on their arrangement.
It seems, then, to result at once from the hypothesis,
that those vibrations which occupy the most time will also
have the highest modulus of elasticity, and that this will be
greatest for the longest waves. But a correct view of the
chemical structure will clearly be requisite, before this
variation can be theoretically traced in particular substances, so as to be compared with the results of experiment.
On this view the hypothesis of finite intervals is still
virtually maintained, but in a modified form.  It is not
likely that the intervals of the ether atoms should have a
finite and sensible proportion to the length of a violet
wave, a distance almost sensible.  But, in the present
modified view, there is a finite ratio between the excursion
of the ether particles, and the interval which separates
adjacent material atoms. Each of these is probably nearly a
billion times less than the length of a wave, and they may
not be widely unequal to each other. For the linearity of




CHAPTER V.                    67
the equation for the pulses of light implies that the duration is insensible, compared with the wave's length; while
the previous comparison of known conditions leads to the
inference that the mean distance of the material atoms cannot very greatly exceed that of the atoms of free ether.
44.  To ex2~lain the Polarization of Light.
Polarization, in the Undulatory Theory, is accounted
for by the transverse direction of the luminous vibrations.
There are two directions, at right angles to the path of the
ray, in either or both of which the particles may oscillate.
Light is said to be polarized in any plane, when all the
vibrations in that plane have been extinguished. When
a ray travels horizontally, and is polarized in the vertical
plane, the monads are conceived to move horizontally, at
right angles to the line of the ray; and when polarized in
the horizontal plane, the vibrations are held to be vertical. Very many remarkable phenomena have been thus
explained. There are, however, some difficulties that have
still to be removed, and Sir J. Herschel has stated them
in these words.
"It may be objected that the molecules of the ether,
if it be a fluid, cannot be supposed to be connected in
strings or chains, but must exist independent of each other.
But it is sufficient to admit such a lateral adhesion (we
hesitate to call it viscosity) as may enable each molecule
not only to push those which lie before it in the plane
of its motion, but to drag along with it those on either side.
It is true the properties we must attribute to the ether
appear to belong to a solid rather than a fluid, and may
be regarded as reviving the antiquated doctrine of a plenum. But if the phenomena can thereby be reduced to
uniform and general principles, we see no reason why that,
5-2




68              ON MATTER AND ETHER.
or any still wilder doctrine, may not be admitted; not
indeed to all the privileges of a demonstrated fact, but
to those of its representative or locum tenens, till the real
truth shall be discovered."
The difficulty, from the implied resemblance of the
ether to a solid rather than a fluid, is more apparent than
real.  The feature which distinguishes fluids fonom solids,
is the want of polarity, resulting probably from the rotation of the atoms. But the mnonads of ether can have no
such motion, and have therefore no true analogy with
those of fluids.  Their action on each other, under the
assumed law, will have all the marks of strong polarity.
If dlisposed in cubes, the repulsion along the side will be
64 times greater than along the diagonals, and 729 times
greater than along the diameters of the cubes.  The
seeming difficulty, so far, is only a necessary result of the
asstuned theory.
The chief difficulty consists, not in the presence of
strong polarity, like that in solids, but in the repulsive
character of the force.  For points united by a strong
attraction have a close resemblance to an elastic cord;
but repulsive forces tend to increase any actual divergence,
and the restoration must depend on some external pressure.
The transverse direction is here, too, a further difficulty.
We cannot easily conceive them  separated from  direct
vibrations still more powerful, since the direct must probably exceed the lateral force of restoration.
45.  Let us first inquire what will be the structure of
the ether, or the general law by which its particles will be
arranged.  Assuming the mean distance of the particles
to be constant, they will be packed as densely as possible;
or a given number in a given space will be so arranged,




CHAPTER V.                      69
that the mean distance of the nearest shall be a maximum.
But the mean distance being the same, the density in a
tetrahedral is to that in a cubical arrangement as 3 to 2
nearly.  Hence the ether must assume a tetrahedral structure, and in the same plane will lie in equilateral triangles,
or in radial lines at 600 of inclination.
Again, for small displacements, the direct force will
vary as the displacement, and the lateral, as that displacement into the cosine of the inclination.  Hence, in the
actual arrangement, when a particle pushes others in a
direct line, the forces in the two inclined directfions will
be one half on each side, or one half of the vis viva will
be transmitted in the direct line, and one fourth in each of
the two lateral lines. The motion, then, excited by a
few particles cannot be transmitted to any sensible distance,
since it would be reduced to one thousandth part after ten
or twelve intervals.
Considering only the particles in the same plane, in a
tetrahedral arrangement, three fourths of the vis viva of
any impulse will be propagated in the direct line to
the next monads, and one fourth in the two lateral directions at right angles. Again, supposing a circular disc
of some size to be moved suddenly forward, it is plain
that the whole vis viva will be communicated in the forward direction, except what escapes laterally at the periphery of the cylinder, or that which forms a reactive or
backward wave, from  the lateral recoil.  The impulse
will become weaker and weaker, with the distance travelled, even in the front, and will decrease rapidly in
intensity, as the line diverges from that of the first disturbance. Every direct oscillation will produce one at
right angles, and it seems to follow, from the fundamental




70             ON MATTER AND ETHER.
law of arrangement; that both will be contemporaneous,
or of equal elasticity, that the vis viva of the direct, will
be double that of the transverse motion, and the last be
equal in the direction of three axes at right angles to the
path of the wave and at an angle of 1200 with each other.
So long as a wave travels in vacuo, the ether will
be symmetrically disposed, and the lateral vibrations
which accompany the direct disturbance will have an
equal movement in every plane which passes through
the axis, or line of the wave. But when the ether is
permanently condensed or compressed in certain lines, as
in transparent solids, then the lateral disturbances, being
at right angles to the path of the wave, will vary in their
character, according to the internal structure.  For the
path of the wave, by the general laws of mechanics, must
be in the line of least resistance, or the direction in which
the ether is freest to move.  The direction at right angles
to this line of least resistance must be that of greatest
confinement, or where the elasticity increases rapidly with
the amount of displacement.  Hence, while the path, being
no longer direct, will cause a general retardation of all
the waves, direct or transverse, the transverse waves,
when longest, or the duration is greatest, will experience
a relative acceleration above the direct waves, from this
increased elasticity.
46.  To explain Circular Polarization, in contrast with
Common Light.
There is a difficulty, stated by Professor Airy at the
close of his Tract, in explaining the distinction between
common light and light elliptically polarized.  "The
most general kind of light that we can conceive," he there
remarks,  "is elliptically polarized, as the union of any




CHAPTER V.                    71
number of vibrations in any directions, and following at
any intervals, will produce it. Common light, then, must
be elliptically polarized. The phenomena of interference
compel us to suppose that common light consists of elliptic
vibrations, many of which are exactly similar. Yet the
difference of the phenomena shews that common light does
not consist of an indefinite number of similar elliptic
vibrations."  The solution he proposes is, that in common
light some thousands of waves are of the same ellipticity,
after which there is a sudden and abrupt change to waves
of a different species. The waves of the same kind must
be numerous enough to produce all the coloured rings, but
be compensated by those of a different kind in every
single impression made upon the eye.
This notion, however, of a series of incessant and
abrupt changes in all common light is very improbable,
and hardly consistent with mechanical laws, which would
require the change to be gradual, and not discontinuous.
But the difficulty seems to arise from the assumption that
a ray consists of one filament only, and that the intensity
of the light is measured by the amplitude of the vibration
alone. In that case an elliptic vibration would be the
mnost general description of a wave. But if the intensity
depends on the vis viva, or:nzv2, for many related filaments, their vibrations may be in different planes around
the common axis, and the difficulty ceases. Common
light, on this view, may be called cylindrically polarized,
each filament being polarized in one plane, but those
planes radially disposed around the axis of propagation;
while, in circular or elliptic polarization, each vibration is
a circle or ellipse, and the particles form a helix or spiral.
Let us suppose an exciting cause, by which a series of




72             ON MATTER AND ETHER.
waves are transmitted from A towards B.  After a short
time there will be a balance between the supply of vis
visa fiom 1A, and its dispersion laterally along the line.
There will be a direct undulation along the axis, and
secondary transverse vibrations at right angles to it, propagating themselves in the same line with equal velocity.
All the displacements may be assumed to be infinitesimal,
compared with the length of the wave. Every pulse of
light'will imply an axis of direct vibration, accompanied
by transverse vibrations, collectively only one thi-id in
amount, but of the same velocity, performed in every
plane which passes through the axis of onward motion.
The polarization of light will consist in the extinction
of all the transverse vibrations, except those in one and
the same plane. Two such waves, polarized in planes at
riglht angles, and combined at the interval of one fourth of
a wave, will produce circular polarization, or elliptical
polarization, if the two waves thus combined are of unequal
intensity.
47.  To excpain. the probable relation between Ligz t ancl
fRadiant feat.
Light, by the received theory, consists wholly of transverse vibrations.  But it seems to follow at once, from the
nature of an elastic medium, that these must be joined
with direct vibrations, even superior in force; because, in
a tetrahedral arrangement, the whole lateral vis viva is
only one third of the total amount. Any theory must be
defective, which leaves this direct vibration unexplained.
Now it is plain that light and heat are usually joined
together in the case of luminous vibration.  Let us assume
that all the direct vibrations are included under radiant
heat, and the facts will be at once reconciled to the claims




CHAPTER V.                      73
of mechanical law.  Bodies usually require a high heat to
become luminous, andc the red rays, which answer to the
long'est waves, and have the greatest momentum, are the
first which are visible.  In other words, the direct vibrations must reach a certain degree of intensity, before the
transverse ones, always feebler, have power to affect the
nerves of the eye.
Heat itself, however, it has been proved latterly, admits of being polarized.  We must assume, then, still
further, that all pulses constitute radiant heat, in proportion to their vfs vivca; but that only transverse ones, and
these within fixed limits of length or duration, are sensible
to our eyes.  Radiant heat will thus include both direct
vibrations, and transverse ones beyond the spectrum, besides the luminous rays themselves.  Now both of these
last will plainly admit of being polarized.
In the experiments of Professor Forbes, the heat from
different sources polarized through plates of mica, gave the
following proportions.  Brass, at 3900, 19 per cent.; mercury, at 270~, rather more; incandescent platinum, 54- per
cent.; water, under 2120, 5 per cent.  By reflexion, Argand lamp, 55 per cent.; brass, at 3900, 61 per cent.; platinum, 63 per cent.
These results agree well with the present explanation,
if we assume that dense substances have a coercive power
over the direct vibrations, increasing with the cohesive
force; just as two polished surfaces may slide easily on
each other, but offer great resistance, to pressure, or
on direct separation.  The direct vibrations, in water,
would be 95 per cent.; in brass, 81; in mercury, about 78;
while in platinum, the densest and most cohesive  of
metals, they are only 46 per cent. of the whole anmount.




74             ON MATTER AND ETHER.
48. An explanation has been proposed, in Professor
Kelland's Theory of Heat, on the hypothesis that the
vibrations of heat also are transverse only. The formula
for the polarization of Light when a is the analyzing
angle, I the retardation, and X the length of the wave, becomes
E= a' (cos2 a - cos 2a sin'2 -X).
For the maximum we have I= X, and the effect becomes E= a2cos2a. The assumption proposed is, that in
the case of heat I= -, or the length of the wave four
times greater than for light. But this is plainly an oversight. From  the nature of the formula, X must be the
length of the wave for the polarized rays themselves, and
I= X for the maximum in every case. On the proposed
hypothesis, since -  would be 45~, the intensity would be.-a2 in every position, and polarization must entirely cease.
On the other hand, the facts agree perfectly with the
explanation now offered. For it will result that the direct
are more powerful, or have greater vis viva, than the transverse vibrations in every case but one, that of platinum.
And here there is a simple key to the exception, the
coercive power of this densest and most coherent of metals
taking effect mainly, if not exclusively, on the direct vibrations, which begin at right angles to its solid surface.
49.  To explain the oriqin of the dark lines in the solar
spectrum.
These are held, by general consent, to be one of the
most interesting, but also one of the most perplexing, of
optical phenomena.  " The bands are constantly in the
same parts of the spectrum, and preserve the same order and




CHAPTER V.                     75
relations to each other, the same proportional width and
obscurity, whenever and however they are examined; provided solar light be used, and the prisms are composed of
the same material. A difference of material, though it
causes no change in the number, order, or intensity of
the bands, or their place- referred to the coloLurs, causes
variations in their proportional distance. In the light of
stars, in electric light, and that of flame, similar bands are
observed, but they are differently disposed, and the spectrum of each star, and each flame, has a system of its own,
characteristic of its light, which it preserves unchanged in
all circumstances."
The simplest hypothesis, to account for this singular
phenomenon, is that some change passes on the light in
each case, when it emanates from the sun, star, or terrestrial flame, by which the answering parts of the spectrumn are absorbed and extinguished.  Now whatever be
the source of light, it must be connected with material
atoms, and among these some one or two atomic intervals
of distances may be expected to prevail. Hence vibrations,
in which the lengths of waves are the simplest multiples
of these distances, will be favoured and maintained by the
frequency of new pulses, while others will be extinguished,
or have their force decreased. The simplest multiples will
be those by powers of two, the next by those of three, and
so on for the lowest primes.  Let us now, beginning with
10000, write down the numbers which have only 2, 3, 5
for their factors, and we shall plainly have a series with
irregular gaps, where primes, or composites of higher factors occur.  If two such series, with incommensurable
units, are superposed, the gaps will be diminished, but
some spaces will still remain. In passing, also, through a




76             ON MATTER AND ETHER.
dense medium, each ray may probably have its breadth
extended from a mathematical line to a limit depending on
the distance of the nearest atoms. Thus, if the length of
the refracted wave were greater than 1000 and less than
1000 times the distance of the atoms, the vibration might
be forced into coincidence with these extremes,, and its
spectrum spread over this interval.  Every source of light,
on this view, will produce dark spaces in the spectrum,
not filledl up by waves of particular lengths; and with
different sources their position and number may be expected to vary, as they are found to do.
50.  To explain the relations betzeen Light and Sount,
with respect to the varieties of musical tones, and of coloured
rays.
The view has been prevalent of late, that solar light
contains only three fundamental colours, red, yellow, and
blue, wlich overlap each other, and may be separated by
media of different absorbing power for different kinds of
colour.  Thus Mr Huint remarks in his Report to the
British Association of Science on Solar Radclation.
" On examining the spectrum of seven colours, we must
at once perceive that these are composed of three -red,
blue, and yellow. Examining it with coloured media, we
can detect extensions of these primary colours, and fair
evidence is afforded that these bands overlap each other.
If we look at it through a cobalt blue glass, a colour
unseen by the naked eye becomes visible, the extreme
red ray.  This is evidently the result of a mixture of blue
and red. By throwing the spectrum  on turmeric paper,
a portion is seen beyond the violet, to which Sir J.
Herschel gave the name of the lavender ray.  Now if we
examine all the conditions of these colours, we find that




CHAPTER V.                    77
the yellow ray blends with the blue, and produces green;
that the blue becomes more and more decided, passing to
blackness in the indigo, but that the red reappears, and
mixing with the blue, produces violet, and yellow blending with the violet produces the lavender ray. On the
other side, yellow mixing with red produces orange, and
then the red, growing in intensity and purity, again blends
with blue, to produce the crimson or extreme red ray."
ieRasons,, however, of much weight have been offered
for the opposite view, that the rays are simple, and not
compound. For if the intensity of the light depends on the
amplitude or momentum of the vibration, it is not easy to
see on what the colour can depend, but on the length
of the wave; just as the pitch of a note depends on the
frequency of the aerial vibrations. But the length of the
orange wave is just as definite as that of the red, yellow,
or blue. And since all, when combined, produce only
whiteness, any three tints, chosen wide apart, may be so
combined. as to produce any other tint whatever. In fact,
Dr Young selected red, green, and violet for the three fundamental colours.
Again, if two vibrations, with a different length of
wave, are combined together, the result will be doubly
periodical, its two periods being the half sum and half
difference of the two separate rates of vibration. But the
period which depends on tile half difference must answer
to a simple wave beyond the limits of the spectrum.
Hence that which depends on the half sum will alone be
sensible to the eye; and this answers to a wave of the
intermediate colour.
The affection of sight, also, in those who can distinguish only two colours, is a great difficulty in the way of




78             ON MATTER AND ETHER.
the hypothesis that there are three only, fundamentally
distinct, so as to produce the rest by their combination.
For here the eye is sensible to all the rays, but wants the
power to discriminate red firom yellow rays.
The hypothesis, also, of three distinct spectra, which
overlap each other, departs wholly from the strong natural
analogy between light and sound, and replaces it by the
foreign idea of material substance, and chemical composition. Since light and sound result alike from vibrations,
it is natural to expect some close resemblance between the
laws of colour and musical tone. The attempts to trace
it, by comparing the breadths of coloured rays in the
spectrum  with musical intervals, or as some have done,
with three chemical elements, have also a very arbitrary
and empirical appearance, and are inconsistent with the
fact of a variable dispersive power. But it does not follow
that the analogy may not exist, and be traced out in a way
which shall be free from all these objections.
51. MIusical Tones and Colours comvpared.
Light and sound both result from periodical vibrations,
one of air, the other of ether; and the general sensation is
attended, in each case, with a vivid perception of musical
pitch, or of colour. There is concord and discord in
sounds, and a perception, hardly less vivid, of harmony or
discordance in colour also.  Some ears are insensible to
minute differences of pitch or tone, and some eyes are
equally insensible to many variations of tint. There are
three fundamental notes in the octave; and there are also,
in the view  of most, three fundamental and primary
colours.
The contrasts, however, are hardly less striking.  The
range of sounds includes six or seven octaves, while the




CHAPTER V.                     79
whole spectrum, so far as sensible to the eye, is less than
one. The musical scale has a series of definite notes,
while intermediate sounds create a sense of discord.  But
the spectrum, except in the black lines, is one gradation of
tint, and still gives an impression of singular beauty. The
mixture of two colours produces an intermediate tint, but
the striking of two notes together, a definite concord or
discord.  Coloured rays, again, seem  of themselves to
create a vivid sense of beauty; while in music it arises
chiefly from the combination of sounds, and a definite relation between them, and a small deviation excites a senlsation wholly opposite, or that of dissonance and discord.
These contrasts and resemblances may be explained in
the following manner.  The vibrations of light, being a
billion times more rapid than those of sound, lie wholly
beyond the reach of separate observation; whereas the
slowest, in music, are only sixty in the second, or hardly
one remove from  being capable of direct enumeration.
Hence definite recurrences of the vibrations, as in the musical third, where every fourth and fifth coincide, will be
directly cognizable, and produce a sensible impression of
agreement and harmony.  In the case of light, this approach to distinct perception of the component vibrations
must be impossible, and the contrast between concord and
discord, arising from slight variations of pitch, destroying
sensible periodicity of the two pulses, will disappear.
Again, the frequency of the vibrations, and the nature
of the medium, render a more sensitive organ necessary to
apprehend them. This might be expected to limit the
range of its perceptive power; as the eye, the organ of
sight, is much smaller and more delicate than the hand,
the organ of touch. Accordingly, the spectrum is found
In~J    LVCLVI~LL 1 N-V~I~




80             ON MATTER AND ETHER.
to be withill the range which answers to the musical
octave.
Thirdly, this limited range of power, if assumed to be
constant for the same eye, or even for different eyes, must
create a natural standard, to which every ray may be instinctively referred. For every vibration, by the laws
of mechanics, will be attended by its octave, either above
or below. Hence the rays just beyond the extreme red
and lavender will form natural limits to the sensibility of
the optic nerve. Accompanying one another at the distance of an octave they may produce no sensation of
colour, but exercise an exciting power, so as to form  a
secret, natural standard for the rest; a natural pitch for
the liminous tones, which will be a contrast to the arbitrary pitch, consequent on the wider range of the musical
scale.
This easy assumption being made, the analogy, in
other respects, may be carried out without much difficulty.
The simplest ratios of vibration to the limiting or fundamental tone will occasion a specific sensation, associated
instinctively with each part of the surface from which such
vibrations emanate, which will form a primary colour.
Secondary ratios, in like manner, will form  secondary
colours.  Those colours will be felt to be pure and vivid
in which the wave length is nearest to the defining ratio,
and those impure which lie between them.
52. The simplest ratios in nmusic have two for their
base, and are formed with the next primes 3 and 5. Thus
2 is the octave, 3 the fifth, 4 the third, and 9 the major
tone. Beyond this limit the ear is not sensible of concord
in the same series, and 1, not -, is the chromatic semitone.




CHAPTER Y.                     81
Now in Light, if we assume 424 billions for the vibrations per second of the fundamental wave, we have these
relations.
9  8 = 477 billions = red ray exact; 5  4 = 530 billions
(535 Hersch.) = yellow ray; 3: 2 = 636 billions (644 = b intermediate to blue and indigo); 4: 3 = 565 billions (b in
the green); 5: 3 = 707 billions (H. centre of violet).
Thus the three primary ratios, answering to the major
tone, major third, and fifth in music, correspond with
red, yellow, ancd blue, which by general consent are the
three primary and simplest colours.  The ratios next in
simplicity, where three is the divisor, or the musical fourth
and sixth, correspond with green and violet, which are the
colours next in order of simplicity, so that Dr Young
selected red, green, and violet for the three simplest. The
next ratio is 6: 5 =509 billions, and corresponds exactly
with the orange ray, and in music with the minor third.
The agreement, then, between the scales of light and
sound is complete, when once we assume a ray beyond the
red for a natural unit of comparison, or a fundamental
pitch in the series of luminous waves.
Again, the waves beyond either limit will be octaves
of those near the opposite limit.  They may be rendered
luminous by union with another ray, because the new
mean, from the half sum of the lines of their vibrations
will be within the limit of visibility.  In this case they
must seem nearly identical in their properties with the last
visible rays at the other limit, just as a note and its octave
sound together almost like a perfect unison.
53.  It will result, from this view, that the rays of the
spectrum are not, strictly speaking, compound; but that,
specific ratios in their vibrations, referred to a fixed limit
6




82             ON MATTER AND ETHER.
of visual power, give rise to the sensation of each primary
colour; and the combination of two of these, because the
period of the half sum prevails over that of the half difference in the compound period, will resemble the tint half
way between them, but with some defect in purity and
brightness of tone.
Again, the most usual variety of the imperfect vision,
called colour blindness, is the incapacity to discern more
than two fundamental colours, yellow and blue. This is
easily accounted for on the present hypothesis. For the
next ratio to the major tone is 17: 16, and is insensible as
a concord, or as a fundamental shade of colour. Now if
this limitation in the power of the ear or eye were carried
one step further, then the eye will appreciate the ratios
3: 2 and 5: 4, but not 9: 8. Consequently only yellow
and blue, to the exclusion of red, will be left for the fundamental colours, of which all the rest will appear to be
varied combinations.
54. Lumzinous and Xon-l'uminous Matter.
Another subject, on which theory needs to throw fresh
light, is the source and nature of luminosity. It is often
assumed that the sun and stars are composed of matter
different in kind from the substances with which we are
familiar. The present hypothesis would exclude all possibility of such an absolute contrast. We are thus led to
the inference that the sun's luminosity is due, in some way
or other, to its immense relative mass, and its central
position.
The chief known sources of light are combustion or
incandescence, phosphorescence, that is, a weaker and insensible kind of combustion, and solar radiation.
In combustion it is plain that the chemical atoms enter




CHAPTER V.                     83
into new and more intimate combinations.  The effect
must be that vis viva is largely increased; which may
take the form of rapid oscillation, that is, high temperature
of solid products; rotation of the new atoms, or the specific
heat of fluidity; or rapid translation, where the products are
gaseous. But in all cases alike there must be those ethereal vibrations, from  which pulses both of light and of
radiant heat usually arise.
Again, the whole pressure of an atmosphere on its
lowest stratum equals the weight of the column, and hence
the total pressure throughout the column will be one half
the square of the mass into the mean force of gravity.
But the pressure on each part must equal the repulsive
force developed.  This, again, in a gaseous medium, must
depend on the centrifugal atomic motion, which varies as
the square of the velocity into the mass of each particle.
The same product must represent the vis viva of gaseous
motion, on which the power to excite vibrations must be
conceived to depend. Hence it seems probable that the
collective power to disturb the surrounding ether will be
measured, at least in some rude approximation, by the
total pressure, or the square of the mass in each column,
multiplied by one half the force of gravity at the mean
height.
The mass of the solar atmosphere is unknown.  Let
us assume that it bears the same ratio to that of the
earth as the two spheres bear to each other, reaching from
their centres to the distance of equal attraction.  Then,/J  will be the relative mass of the sun's atmosphere, /3
its square, /2 the relative amount for the unit of surface,
L4 r-6 the relative luminosity, or collective pressure for the
6-2




84             ON MATTER AND ETHER.
unit of surface, and /r'4 the relative amount of light. On
this hypothesis, the luminosity of the sun would be 12127k2
millions, compared with that of the earth, and compared
with Jupiter 1-  millions. By this formula, the earth would
have a native light, forty thousand times less than that of
the sun which falls upon it, and Jupiter, on the contrary,
a native light, equal to or greater than what it receives.
Now  if Venus and Jupiter shone only by reflected
light, the amount they transmit from a unit of surface
should be as 50 to 1; and when she is in her maximum
brilliance, and Jupiter in opposition, the disc of Jupiter is
very little larger in visible size than hers. Assuming the
crescent to be one fourth of her disc, her light on this view
should be twelve times greater.  The disparity, however,
it seems certain, is considerably less. And hence there
seems to be somd direct presumption that Jupiter, the
"'lustrous star" of astrology, has really a native light,
distinct from that which he receives from the sun. The
auroras, again, are a native earth-light, and offer a further
illustration of the same view. Luminosity, it is highly
probable, is some function of the mass of each sun or
planet, and of its velocity of motion, or the height of its
atmosphere, though the exact function by which the two
are related may not be easy to ascertain.




CHAPTER VI.
THE CHEMICAL ELEMENTS IN GENERAL.
55. THE Elements of the ancients were fire, air, earth,
and water, answering to four general forms or conditions
of matter, which is either solid, fluid, gaseous, or igneous.
Modern science, however, applies the name to those kinds
of homogeneous substance, which have not at present been
resolved into each other, or into any simpler form. The
total number of these is rather more than sixty, but one
or two are doubtful, and several others of rare and limited
occurrence.  Hydrogen, oxygen, nitrogen, chlorine and
fluorine, are gases; bromine and mercury are fluid at common temperatures; and the rest are solid, but the heat
required for their fusion differs widely, and carbon, one of
the most important, is infusible. The greater part, about
fifty in number, have sufficient general resemblance to
receive the name of metals. In their density and other
properties, however, they differ widely. Potassium  and
sodium are lighter than water, while platinum and iridium
are more than twenty-one times heavier. When binary
compounds are analyzed by a galvanic current, the same




86             ON MATTER AND ETHER.
constituent in the same pair always goes to the same pole.
Those which go to the positive pole are called electronegative, when compared with those which go to the
negative pole. Hence all the elements may be arranged
in a series, from the most electro-negative to the most
electro-positive, nearly as follows:
Oxygen, chlorine, iodine, fluorine, bromine, sulphur,
nitrogen, phosphorus, selenium, arsenic; chromium, molybdenum, tungsten, boron, carbon, antimony, tellurium,
tantalum, titanium, silicon; osmium, hydrogen, gold, iridium, rhodium, platinum, palladium, mercury, silver,
copper; uranium, bismuth, tin, lead, cerium, cobalt,
nickel, iron, cadmium, zinc; manganese, zirconium, aluminium, yttrium, glucinium, magnesium, calcium, strontium, barium, lithium; sodium, potassium.
Oxygen, chlorine, iodine, fluorine, bromine, which are
highest in this list, are supporters of combustion.  Sulphur, phosphorus, selenium, boron and carbon, are comnbustibles.  Arsenic, chromium, molybdenum, tungsten,
antimony, tellurium, tantalum, titanium, osmium, are acidforming metals. Then follow neutral metals.  Silicon,
zirconium, aluminium, yttrium, glucinium, are bases of
simple earths; magnesium, calcium, strontium, and barium,
of alkaline earths; and lithium, sodium, potassium, of simple alkalies.
Some of these elements exist in very large quantities.
Others, especially some of the late-discovered metals, are
found only in very rare minerals, or in very minute proportions. The recent ones, and little known, are donarium,
didymium, erbium, terbium, ilmenium?, lanthanium, niobium, pelopium, norium, ruthenium, thorium, and vanadium.  The immense contrast in the width of their diffu



CHAPTER VI.                   87
sion, and the small proportion of some which appears to
exist, is a first presumption that the present elements, or
at least the greater number of them, are really compound,
and not simple and ultimate kinds of matter. For in this
case, it is plain that some combinations would occur only
under rare and exceptional circumstances, while others
might be expected to be of frequent and ordinary occurrence.
56. Each of these chemical elements is found to have
an equivalent, or atomic weight. In other words, a list of
numbers can be framed, which represent the relative
weights in which they combine, either directly, or in some
simple multiple, however various the pairs or triplets which
enter into combination. These numbers are naturally inferred to represent the relative weights of the chemical
atoms themselves, or those smallest portions, which, by
their union with each other, form chemical compounds.
The ratio between hydrogen, the lightest, and gold, the
heaviest, is 1 to 197. Out of sixty, however, there are
only five or six of which the atomic weight is more thawm
a hundred times that of hydrogen, and more than one half
are less than 50.  On the other hand, the lowest after
hydrogen, or carbon, is six times heavier than that element. Thus the distribution is more nearly geometrical
than arithmetical. No atomic weights occur between one
and six, about one-half between six and thirty-six, and
the highest is less than 216.
Mr Dalton, the discoverer of Chemical Equivalents,
not only assumed that they represented the weights of the
ultimate atoms of the elements, but that these were spheres,
and formed chemical compounds by juxtaposition.  He
invented diagrams to represent the order in which they




88             ON MATTEI  AND ETHER.
might be combined.  But these arrangements had no dynamical character, and could therefore account for none of
the properties, either of the simples or of their compounds.
The conception, then, in this its first shape, has remained
sterile and unproductive.
Another hypothesis assumes that the chemical atoms
are centres of attractive and repulsive force, varying as the
inverse square, but differing for each in its constant of
force, and also in the distance at which the force changes
suddenly from attraction to repulsion.  On this view, however, the number of arbitrary constants introduced is at
least twice as great as that of the chemical elements, and
all explanation of the atomic weights themselves, and of
remarkable relations which they exhibit to each other, is
set* aside.  The properties of the elements, also, might
then be expected to graduate into each other, when arranged by the order of their atomic weights.  But an
inspection of the lists will shew that substances, differing
little in their atomic numbers, differ widely in their properties, as fluorine and calcium, or chlorine and potassium;
and that others whose atoms are very unequal, have a
strong resemblance, as sodium and potassium, molybdenum
and tungsten, and others.  No explanation of the nature of
atoms can be correct which does not shew dynamical consequences resulting directly from  their union, and then
varying by some other rule than the atomic weight
alone.
57. Atomic weights, in many elements, are multiples
of the hyclroqjen unit.
WThen the doctrine of equivalents was first established,
attempts were made, by Drs Prout and Thomson, to shew
that all were multiples of hydrogen, and most of them even




CHAPTER VI.                    89
multiples. The later, and apparently more exact experiments of Berzelius and Turner tended, in some degree, to
overthrow this hypothesis, and to establish broken or fractional values for many elements. Yet even their experiments, rightly considered, left the presumption in its favour
very strong in the case of carbon, nitrogen, oxygen, and sulphur, some of the elements which are widest and most universal in their range. More recently, the analysis of Peligot
and others has re-established integer values for chlorine,
iodine, bromine, silver, and titanium.  Even as the result,
then, of experiment alone, the view seems now renderecd
probable, that all or most of the atomic weights are integers, if hydrogen, or else half-hydrogen, be taken for the
unit.  The following integer values, including many of
the chief elements, may now be viewed as tolerably well
ascertained:
Carbon 6, Oxygen 8, Boron 11, Magnesium 12? Nitrogen 14, Sulphur 16, Fluorine 19, Calcium 20, Sodium 23,
Titanium 25, Iron 28, Phosphorus 31? Chlorine 36? Potassium 39, Miolybdenum 46, Cadmium  56, Tin 58, Tellurium 64, Uranium 60, Arsenic 75, Tungsten 92, Iridium
99, Mercury 100, Silver 108, Iodine 127, Antimony 129,
Bismuth 71 or 213, Gold 197.
it is plainly the low atomic numbers, which yield the
most decisive evidence for or against the acceptance of
integer values; and in the case of carbon, oxygen, nitrogen,
sulphur, fluorine, calcium, iron, the reality of the relation
stands out in clear and strong relief. In some others, the
diversity of the earlier estimates has tended to interfere
with the evidence for its truth.
Now if all the atomic weights were proved to be exact
multiples of that of hydrogen, the natural inference must




90             ON MATTER AND ETHER.
be that they are compounds, and that a certain number
of hydrogen atoms, combined in some especial way, form
the atom of every other element.  Again, if many of them
are multiples of hydrogen, but others fractional, the natural conclusion will be that hydrogen itself consists of two,
three, or some small number of ultimate monads, of which
last all other elements are composed.  One of these alternatives seems to result plainly from the results of the most
exact determinations of the atomic numbers, and either of
them is in plain agreement with the present theory.
58. Isomeric Elements.
Several of the chemical elements are capable of assuming different forms, distinguishable from  each other by
strong chemical characters. Thus "the crystals of sulphur
exhibit two distinct and incompatible forms, an octahedron
with a rhombic base, the figure of native sulphur, which is
assumed when sulphur separates from solution at common
temperature; and a lengthened prism, having no relation
to the preceding, when a mass of sulphur is melted, and
after partial cooling, the crust is broken, and the fluid portion poured out."  Carbon has wholly different qualities,
as charcoal, and as diamond, and its crystals are of
two or three wholly different forms. Phosphorus, again,
as amorphous phosphorus, differs widely from its usual
structure, is red, opaque, and- insoluble in bisulphuret of
carbon, and is one fifth denser than common phosphorus.
Phosphoric acid, again, though composed of phosphorus
and oxygen in the same proportions, has three distinct forms,
which electricity disengages, without change, from  the
salts into which they respectively enter. Oxygen, also,
exists under a second form, as ozone, in which it has a
sulphurous smell, and enters more readily into composition




CHAPTER VI.                   91
with metals. All these facts, in the case of substances
reputed simple, tend strongly to justify the suspicion that
they are really composite, and that their constituent atoms
may vary their manner of combination.
59.  Simple and Gompound Elements.
The Four Elements, Hydrogen, Oxygen, Carbon, and
Nitrogen, form a remarkable contrast with all the rest by
the multitude of distinct combinations which they form,
and which constitute almost the exclusive subject of vegetable and animal chemistry.  Some thousands of such
compounds have been separated from natural products, or
artificially formed, and the total number of atoms which
enter into the compound atom, and fix its combining equivalent, is sometimes not less than a hundred.  On the
other hand, the other elements, in general, form only
binary compounds, and after two binary stages, we reach
the limit of their combining power. Of these four elements
hydrogen is the lowest, and carbon is next to it, in its
atomic weight, while oxygen and nitrogen are among those
which come nearest to them  in the smallness of their
equivalents. The remarkable contrast between their powers
of multiplied affinity, and the more restrictive capacity
for union of the other elements, points naturally to the
conclusion that all alike are real compounds, except possibly hydrogen alone, and that the simplicity of the compound structure in these lighter atoms makes them capable
of a wider range of secondary composition.
60. Properties of lWater, a presumption for the composite c.aracter of thte simpgler elements.
Water was taken to be a simple body, and one of the
four elements, till the time when it was decomposed by
Cavendish and other chemists.  Since then, it has ranked




92             ON MATTER AND ETITER.
as a binary compound of oxygen andl hydrogen gases,
though totally distinct in character from both of its constituents.  But this view, though the natural result of discovery in its present stage, presents gieat difficulties to a
thoughtful mind, when compared with the great facts of the
universe. The quantity of water connected with our globe
is probably four thousand times greater than all the free
oxygen of the atmosphere.  Its immense quantity has
plainly made it one chief agent in the whole geological
history of our planet. We seem to have distinct proof of
its presence in large quantities, in the planet Mars, and,
there is little doubt, in still larger quantities in the superior planets. Its properties, again, as an almost universal
solvent, seem to give it the same rank, for simplicity,
among liquids, as hydrogen, from its lightness, occupies
among the gases.  Its combining equivalent also is less
than fifty out of the sixty elements, and indeed there are
only four substances, now reckoned elements, which rank
below it in this respect, and two of these are its own components. Again, it is now admitted by chemists, to have
many of the relations of a metal of weak affinity for oxygen,
with which it is made to combine by a laborious process.
All these facts agree best with the idea, that water is really,
in a certain sense, the simplest of the metals, that the other
metals, of higher equivalents, are also compound, though'
our present methods have not decomposed them, and that
the strong contrast between the electric affinities of oxygen
and hydrogen, enabling us, in this case, to resolve the
higher into two lower atoms, has accidentally degraded
water, at present, from its true and natural place, which is
higher in order of simplicity than that of the metals themselves.




CHAPTER, VI.                   93
61. Related Atoms.
The suspicion that our present elements are not simple,
but compound, has gained strength of late in the minds of
many chemical philosophers. Professor Faraday has expressed his conviction that it is highly probable, from the
close resemblance among several metals, and the constant
increase of the number discovered. Dumas, again, *has
pointed out several triads of elements, in which there is a
gradation of properties, with atomic weights nearly equidistant. Such are chlorine 35?, a gas; bromine 80, a liquid;
and iodine 125 —127, a solid; and again, lithium = 7 nearly,
sodium 23, and potassium 39; sulphur 16, selenium 40, and
tellurium  64. lMolybdennum  has close resemblances to
tungsten, and just half its atomic number.  Iridium andplatinunm are very near akin, and their numbers are almost
exactly the same. All these facts are best explained by
the supposition that the elements are really compound, and
that these have especial resemblance in their mode of
composition.
62.  To explain generally the formation of Chemical
Atomns.
Every simple atom, on the present hypothesis, consists
of two monads, one of matter, and one of ether, united inseparably into one. The matter of each attracts the ether
of the other by a law, assumed to be the inverse sixth,
or triplicate of the law of gravitation; and the ether repels
the ether by a still higher law, assumed to be the duplicate of the last, or the inverse twelfth. These laws, from
their nature, imply a neutral distance, at which the one
repulsion balances the two attractions, and which must be
supposed very small, not more, probably, than one trillionth
of an inch. W5rhen two such atoms approach nearer than




94             ON MATTER AND ETHER.
this distance, they will repel each other strongly, but when
further apart, they will have a strong mutual attraction.
This excess of attraction will be a maximum  at the distance A/2, and after that will gradually but rapidly diminish.  A  monad of ether will be in equilibrio at a
distance from a material atom, equal to this distance of
greatest attraction for two material atoms.
Two, three, and four simple atoms, apart from foreign
pressure or motion, will thus be tin equilibrio in a right
line, an equilateral triangle, or a tetrahedron, with the
neutral distance for the side. Witlh any greater number
there must be a partial compression, until the excess of
repulsion from this cause balances the amount of the attraction between the non-adjacent atoms. But the compression
will be slight in point of distance, though great forces
may be developed. For a particle at double the distance
will only add j-1 to the forces already balanced, and a
compression  Lt4 will suffice to develop an equal excess of
repulsion.  Compound atoms of this kind will have their
inner monads within the neutral distance, with an excess
of repulsion, or in a state of tension- increasing towards
the centre.
Let us now suppose a motion of rotation around a given
axis. The particles will dispose themselves in a plane
at right angles to that axis, and tend rapidly to assume
equal distances, or the form  of a regular polygon. Its
radius, apart from the centrifugal force, would be such as
to make the side of the polygon slightly less than the
neutral distance. But the centrifugal force, if equal to the
repulsion of the ether, will enlarge the side nearly as ~/2: 1.
With every transfer of vis viva to other atoms, or to the
neighbouring ether, the cycle will contract; and enlarge




CHAPTER VT.                   95
with its increase, so as to find always a position of equilibrium. Such a motion of rotation evidently supplies the
place of a central atom. In other words, revolving cycles
find their equilibrium without a monad in the axis of
rotation, but when at rest, an atom in the centre will often
be needed for stable equilibrium.
63. A cycle of six monads, with a seventh in the
centre, will be in equilibrio at the neutral distance, apart
from a slight compression due to the remoter monads.
One of seven monads, with an eighth in the centre, will be
in equilibrio, when the side is less and the radius greater
than the neutral distance, and so also a cycle of more
monads than eight.  The monads will be attracted to
the centre, and repulsive to each other, and any disturbance, which throws them out of the plane, will produce
a new and more compact arrangement. On the other
hand, if one monad be in the centre, and three, four or five
in the circumference, the action will be reversed. The
tangential action will be attractive, the central repulsive,
and the tendency of disturbance will be to force out the
centre atom to some distance from the plane. But a movement of rotation will alter all these relations. It will first
transfer the excluded central monad to the plane of the
cycle, and if increased further, from the centre to the circumference, so that the moment of rotation may be a
maxinlum.
64. Compounds of several monads may combine in
several different ways. If both solid, or composed of
adherent monads, combined at nearly their minimum distance, they must unite by simple apposition, so that
their centres may be as near as possible.  Flat cycles
might thus be joined face to face, and prisms and cylinders,




96             ON MATTER AND ETHER.
side by side, or end to end. If they are revolving, so
as not to change their own shape, they will repel each
other at their equators, and tend to unite, either pole
towards equator, or opposite poles to each other, on account
of the repulsion of the ether where the two approach nearest. But if one of them is composed of one, two, or more
cycles, revolving round an axis, they may combine radially, so that the hollow cycle shall encompass the other
compound atom. For such a combination it is plainly
required that the vis viva of rotation or atomic latent heat
shall be greater for the compound atom which excludes the
ether after their union.
A  further variety of combinations may result from
the action of the free or uncombined ether. The neutral distance, it follows from the theory, is less, but not
greatly less, than the mean distance of the compound
material atoms from each other. It has been shewn to be
probable that the mean distance of the free ether monads
in space is of the same order, greater than the neutral distance, but less. or not much greater than the distance of
the compound atoms. Hence the ether which fills up the
interstices of solids and fluids, must bear the relation to
the separate atoms, not of an atmosphere to a planet, but
rather of planets to a sun, or be relatively discrete, and
therefore strongly polar. Separate ether monads will combine with the compound atoms at their periphery, and
deport themselves like material monads, except that their
neutral distance is slightly larger. Revolving cycles may
thus be formed, of rather more than double the first radius,
by the mixture of alternate ether monads, and will expand
or contract by a similar law, as the rotation is increased or
diminished.




CHAPTER VI.                    97
65. The pressure of the free ether on the surface of
all solids and liquids must produce a further effect in modifying the relations of the atoms to each other. In transparent bodies, it is plain that the vibrations of ether travel
with comparative ease and freedom, and hence the ethereal
pressure cannot possibly exercise any strong influence in
rendering the structure more compact.  But the reverse
must be true in opaque bodies, where the opacity is one
essential feature, as in the metals.  The immense ethereal
pressure must, in this case, tend to force the atoms more
closely together, and thus to produce a tension, and an
increased repulsion, at the periphery of those atoms, when
they are int equilibrio.  This will naturally increase the
permanence of the groups, which compose the compound
atoms, and thus remove the difficulty which might else lie
against the present view of their formation, that the different elements must then be capable of easy conversion
into each other, which would contradict all our present
experience.
66. The permanence of the compound atoms will be
further secured by their vis viva, or atomic motion.
Let the density of the earth be 5'5, and the atom  of
water 9, or hydrogen the unit.  Then the gravitating force
of one monad on another, at one inch distance, or the velocity in inches per second, will have 3n + 7'2267 for its
negative logarithm. Suppose the cohesive force about six
times less, or its neg. log. =3n + 8, the neutral distance
10IO- or one trillionth, and the mean distance of the water
atoms about five times greater. Then 3n +- 8 = 60 is neg.
log. of cohesion at distance one inch, and 108-60=48,
pos. log. at neutral distance.  But in circular motion
v2=fr,.'. log v= 15, or the velocity of rotation, to make
7




98             ON MATTER AND ETHER.
the centrifugal force equal to the attraction or repulsion at
the neutral distance, must be 1000 billions of inches, or
160 quintillions of revolutions per second. In revolving
cycles with no central atom, the vis viva capable of being
absorbed is plainly still greater, since the centrifugal force
is balanced only by a very oblique attraction of the nearest
atoms. Two such revolving atoms will plainly have an
intense polarity. They will repel each other by their
equators, and will be able to combine only at the poles,
by parting with vis viva on one side, and absorbing it on
the other. In this way two distinct atoms may combine
radially, and vis viva will be produced by their union.




CHAPTER VII.
THE FOUR SIMPLEST ELEMENTS.
67. "THE doctrine of -the alchemists on the transmutation of metals," Professor Faraday observes, " is no
longer opposed to the analogies of science, but only in
some stages beyond'their'present development."  The
same idea has been carried still further by Professor Low,
in his Inquiry into the nature of Chemical Elements. lie
concludes that they are all, probably,'compounds of hydrogen, carbon, and oxygen, or possibly of hydrogen and
carbon alone.  But no approach has been made to any
such view of their composition,!if they are really compound, as will account for the immense variety of their
distinct properties. An attempt will now be made, in the
case of the simpler elements, to bridge over this gulf,
and to make at least a conjectural approach to a complete
theory, which will supply a real explanation, by the laws
of mechanics, for the chief distinctive properties of these
elements.
68.  To explain the disproportion between the atomic
weight of Hydroyen, and the other elements.
There are about 65 known elements, and sixty of them
do not exceed 100 in the hydrogen scale of atomic weights.
7 —2




100            ON MATTER AND ETHER.
The mean interval, then, is 1. But the lowest equivalent,
after hydrogen, is carbon = 6, or the interval is three times
the mean amount.  In point of ratio the interval is much
greater, being one third of the whole proportion between
the lowest and highest equivalents. There must surely
be some reason for this singular break which meets us at
the entrance of the atomic scale.
Let us now assume that hydrogen, by far the lightest
substance known, answers to the simple monad, or dual
atom of matter and ether combined. Three is the smallest
number which can form a closed figure in one plane, and
two is the smallest number of planes which can combine
to make a solid figure. There is thus a sixfold interval
between the monad, and the simplest cyclical atom, which
has a solid character. This is precisely the ratio between
the equivalent of hydrogen, the lightest body known, and
carbon, the lowest in atomic weight of the solid elements.
The same assumption accounts at once for the fact, now
well ascertained, that many of the atomic weights are precise multiples of that of hydrogen. The cases, which. appear to give a fractional value, may be reconciled with it in
three ways —by the supposition of a faulty experiment, or
of a double atomic weight; or lastly, by the conversion of
some small portion of the element into hydrogen in the
course of the experiment.
69. Direct evidence for the greater sniplicity of the
fHydrogen Element.
If Hydrogen be the simple monad, then every other
element might be resolved into hydrogen by a sufficiently
powerful analysis. Where the outmost monads of an atom
are not compacted closely a partial resolution may be possible even by forces now at our disposal. Such a change,




CHAPTER VII.                  101
affecting a very small portion of the substance, might
easily escape notice, and be referred to some other cause,
before the likelihood of its occurrence had been shewn on
other grounds.
Now Sir H. Davy " observed the production of a small
quantity of water during the combustion of the purest
charcoal, indicating a trace of hydrogen."  " But its quantity," Dr Turner adds, "is so small that it cannot be
regarded as a necessary constituent.  It proves only that
a trace of hydrogen is retained with such force, that it
cannot be expelled by the temperature of ignition."
This explanation is not at all satisfactory. There are
many chemical affinities which yield to the heat of ignition. How, then, should a union merely mechanical, and
therefore much less intimate in its nature, hold out against
it? It seems more reasonable to allow that a small portion of the carbon is really decomposed, since a trace of
water appears constantly in the product.
" Sulphur, like charcoal, retains a portion of hydrogen
so obstinately, that it cannot be wholly freed from it,
either by sublimation or fusion. Davy detected its presence
by exposing sulphur to the strong heat of a powerful
battery, when hydrosulphuric gas was disengaged. The
hydrogen from its minute quantity, can only be regarded in
the light of an accidental impurity, and in no wise essential to the nature of sulphur."  Here, again, an opposite
explanation seems far simpler, that, as Professor Low remarks, "a portion of the sulphur itself was decomposed."
A third fact of the same kind was noticed by Dr Pront,
and confirmed by Dr Turner.  "Chloride of silver, however white and well washed, gives out little muriatic
acid at the moment of fusion. When it has been well




102            ON MATTER AND ETHER.
dried at 3000 and then fused, the loss is not appreciable in weight, though still sufficient to redden delicate
litmus paper." This result might arise from a slight retention of moisture, even at that high temperature; but
the analogy of the two previous facts adds weight to the
presumption, that a few atoms of chlorine or calcium may
be decomposed, and furnish hydrogen for the hydrochloric acid.
Again, the whole recent progress of chemistry has
tended to replace oxygen by hydrogen, as the main agent
in a large class of chemical compositions, and to disclose
the immense variety of the proportions in which, along
with carbon and oxygen, it builds up all vegetable and
animal substance. These facts seem to point to the conclusion that it represents matter in its simplest and least
composite form; while carbon, oxygen, and nitrogen come
next in order of simplicity. And the atomic weights of
all these are confessedly simple multiples of hydrogen.
70. To deduce probably some leading properties of
Carbon, Oxygen, and Nitrogen from their atomic numbers.
These three elements, along with hydrogen, build up
the ocean, the atmosphere, and the whole animal and
vegetable world. They stand out thus in relief from all
the rest by the immense variety of their combinations.
Oxygen and nitrogen compose the air; oxygen and hydrogen, the water of the ocean, seas, and rivers; carbon,
hydrogen, and oxygen, nearly all vegetable substance;
while all the four commonly enter alike into the products
of animal life.
The equivalents of these elements are expressed exactly
by the integers 6, 8, 14. The densities, however, of nitrogen and oxygen gases are as 7 to 8; and the relation of




CHAPTER VII.                 103
carbon to nitrogen in cyanogen, their chief compound, is 6
to 7. The researches of Gerhardt and others in organic
chemistry have also led them to prefer double values, 12
and 16, for both carbon and oxygen. The ratio of hydrogen and oxygen is 1 to 16 in the density of the gases, but
1 to 8 in water, their chief and only natural compound.
Hence we infer that the relation of these elements to each
other and to hydrogen may be expressed ambiguously by
the three numbers 6, 7, 8, or by their doubles 12, 14, and
16.
Each of these numbers depends on one of the three
first primes 2, 3, 7. The simplest prime answers to oxygen, the most universal and. active element; the next to
carbon, and the third to nitrogen;: which is just the order
of their abundance and activity in combination.
71. Carbon, again, is the chief base, and oxygen the
chief sustainer of combustion. Nitrogen has a kind of
neutral character, and is marked chiefly by negative properties. "Electricity," Faraday observes, "' determines no
liberation of it from its compounds, which seems to point to
the idea that it is not itself a simple substance. Its most
distinctive feature is a backwardness to combine directly
with other simples, and the weaker affinity of the elements
in its chief compounds."
Let us now conceive 6, 7, and 8 particles disposed in
one plane, and observe the differences that will follow.
Their permanence in that plane implies and requires a
moment of rotation; and conversely, a rotation sufficiently
rapid, will make them form a single cycle or polygon in
one plane. The side'of a hexagon is equal to the radius.
Hence, if each monad were acted on by the two nearest
only, the hexagon of equilibrium would have the neutral




104            ON MATTER AND ETHER.
distance for its radius.  The action of the three further
atoms will produce a slight compression. A single atom,
approaching such a hexagon in the line of the axis would
tend to increase the compression still further, and could
not therefore find a place of rest in the centre of the plane,
but might adhere to it in the axis at some little distance,
until a stronger rotation increased the radius of the hexagon, so as to exceed the neutral distance.
Two single atoms might attach themselves to such a,
hexagon on either side, even when at rest, and will tend to
increase its stability; since, when neutral to each other,
they will be strongly attractive to the cycle itself. A
single atom, also, might rest on the axis between two such
cycles, and tend by its action to draw them nearer togetller. A similar arrangement is clearly possible in the
case of several such cycles. Now it is well known that
there are a series of hydro-carbons, the basis of many
compounds, in which the equivalents of hydrogen are
either one mnore, or one less, than those of carbon; as
Formule CH, Methule C 2H3, Acetule C4 H3, Ethule C 4H5,
Mesitule CO6IH5, Glycerule C611E, Amyl C,,oH,,, and others.
There is here, at least, a prima facie correspondence with
the natural properties of a hexagonal cycle.
"Light Carburetted Hydrogen is not decomposed by
electricity, nor by being passed through red hot tubes,
unless the heat is very intense; when some of the gas is
decomposed, and yields two volumes of hydrogen and a
deposit of carbon."  Such a result seems to flow naturally
from the hypothesis. Its formula CH2 seems to answer to
the case of a hexagonal cycle, with an atom axially joined
on each side. A high temperature answers to a more rapid
rotation, by which the radial atoms would recede further




CHAPTER VII.                  105
from the centre.  WVhen the centrifugal force exceeds the
attraction of the non-adjacent atoms, the radius will exceed
the neutral distance, and the hydrogen atoms will have
nothing to retain them on opposite sides of the centre, but
can slide along the axis with the least disturbance. They
may thus be driven out and separated from the hexagon,
while the vts vi;va, being absorbed or sensibly lessened
by this separation, may change the hexatgon into two
triplets of atoms, the first and simplest element of a solid
structure.
72. A cycle of eight will have relations entirely different. The radius of an octagon, when the side is one,
will be 1'307, and the reduced radius, after the compression
resulting from  the assumed laws, will be 1P267 nearly.
Hence another monad might find a place in its centre, but
not in fixed or stable equilibrium. Before another atom on
the axis can enter into fixed and permanent union, the
eight-fold cycle must be decomposed or divided into two
quaternions, when the nine will assume their most compact
form in the shape of a cube, with eight atoms at the
corners, and one in the centre. Such a particle has plainly
the elements of a solid structure; but since its three axes
are all equal, and its moment of rotation is little more
than one third of its former value in the first arrangement,
it will be clearly most favourable for the assumption of a
fluid form.
Of all substances now reckoned compound, water is by
far the simplest, the most widely diffused, and the most
extensive in its powers of combination. Water and fire,
by general consent, have been the two main instruments
in determining the present structure of our globe. The
mere fact that it is now held to be a compound, while a




106            ON MATTER AND ETHER.
score of metals, found here and there in minute particles,
and separated with much labour from complex minerals,
are viewed as simple, is a clear sign that chemistry is only
in a temporary and provisional stage.
The atomic number of water is 9, and is next in order
to 6, 7, 8, those which characterize carbon, nitrogen, and
oxygen, in its relative simplicity. Measured by this test,
water is really simpler than all, except these three or four
primary elements, and a very few of their compounds,
whether capable or incapable of analysis by processes actually known. This number is the sum of 1 and 8, the
numbers of hydrogen and oxygen, but as the square of 3,
or 3.3, it is intermediate in character between 2.3 the number of carbon, and 2.4 or 4.4 the two values of oxygen,
when these are similarly expressed. Carbon is only known
as a solid, oxygen only as a gas, and water is intermediate
in its properties, being the type of a fluid.
A peculiar amount of heat is generated in the formation
of water. The oxy-hydrogen blowpipe thus becomes one
of the most powerful of chemical instruments. The view
of this combination now offered supplies a clear and simple
explanation. The contrast will here be greater, than in
other cases of combustion, between the latent vis viva of
the simples and of the resulting compound. It is not
simply that the oxygen and hydrogen combine, but that
the oxygen monads, which combine with other elements
in an eight-fold cycle, in this case alone are brought one
step further, and become really four-fold.  We should
infer that, for the same amount of matter, the heat evolved
in the combustion of hydrogen must be greater than for
any other element. On the other hand, for the same
amount of oxygen more vis viva may possibly be set free




CHAPTER VII.                 107
in some other cases, because the oxygen monads approximate to a larger number of monads in the other element.
The experiments of Despretz give the following amounts of
heat for the combustion with equal quantities of oxygen.
Hydrogen 2578; carbon 2967;- iron 5325. Phosphorus,
zinc, tin, nearly as iron. The amount increases with the
atomic weight of the combustible, but when this reaches
a moderate limit, becomes nearly constant. The monads
of the larger atoms, with which those of the oxygen are
most nearly in contact, on which nearness the evolution
of vis viva depends, cannot exceed twice or three times its
own number. But the amount of matter being the same
in the product, the values become —hydrogen 286-, carbon
269, iron 184, zinc 133, tin 184; where hydrogen occupies
the first place. Again, Dalton found that hydrogen, in
burning, raised its own volume of water five degrees, and
light carburetted hydrogen, eighteen degrees. The latter
combines one atom of carbon and two of hydrogen. This
gives the ratio 5 to 8 for the heat from one atom of hydrogen to one of carbon, or about two thirds, atom for atom,
and three times as much for an equal weight.
73. The density of oxygen gas is sixteen times greater
than that of hydrogen. Hence, on the present hypothesis,
we must assume that the gas- consists of two cycles of
eight, or one of sixteen monads. The equivalent from
gaseous density being thus double that inferred from the
oxides, has caused a great schism among chemists, whether
eight, or its double, sixteen, is to be preferred.
A second important fact has been established of late
years, that oxygen is allotropic, and exists in two different
forms. By the action of electricity, the slow combustion
of phosphorus, or contact with the heated vapour of ether,




108            ON MATTER AND ETHER.
it becomes ozone, acquires a sulphurous smell, the power
of oxidizing silver and other distinctive properties. By
passing it through red hot tubes, it is reconverted into
common oxygen. At the same time more recent researches
have seemed to imply the existence of a teroxide of hydrogen with properties very similar, and hardly distinguishable, from those of ozone.
The two facts, of the existence of ozone, and of the
double equivalent of oxygen gas, seem to throw light upon
each other. A  cycle of sixteen, or two cycles of eight,
must be convertible into each other by increase or diminution of the centrifugal force. Now ozone is produced from
common oxygen by the electric discharge, and resolved
into it again by a red heat.  Increase of temperature implies an increase of vis viva and therefore a tendency of the
atoms to assume the form in which the movement of rotation is the greatest, or that of a single cycle in the same
plane.  But the transmission of an electric shock or spark
seems to imply a contrary relation of the atoms, in which
they turn edgewise to each other.  This implies a temporary rotation on some diameter, and a force acting for an
instant at right angles to the principal plane.  The tendency of such a movement must be to change the one cycle
into two of half the size, or it may be, two cycles of sixteen of alternate matter and ether monads. Hence it seems
probable that oxygen gas may consist of single cycles of
sixteen material monads, and ozone of two cycles of eight,
or else two of sixteen, half material, and half of uncombined ether. On this view ozone, which resembles sulphur
in its smell, is also a step nearer to a solid structure than
gaseous oxygen.  Also the atomic weight of sulphur is
16, just double that of oxygen, so that it is no improbable




CHAPTER VII.                  109
conjecture that it may consist of two particles of ozonized
oxygen nnited into one.
74. Oxygen is the great supporter of combustion.
But the cause of the heat thus produced is left whollyunexplained by the theory which regards it as a distinct
and ultimate element. Dr Turner observes, after noticing
the defect of Lavoisier's explanation.-"A new theory is
therefore required to account for the chemical production
of heat; but it is easier to perceive the fallacies of one
doctrine than to substitute another which shall be faultless."
The present hypothesis, I believe, provides a full and
complete explanation. Heat is simply atomic or molecular
vis viva. Sensible heat depends on the oscillations of the
solid atoms, transferred through the repulsion of their constituent or adjacent ether to neighbouring atoms, and producing
vibrations which can radiate freely through air or in vacuo,
like the waves of light. Heat of fluidity consists in the
v;is viva of each atom in revolving on its own axis of
greatest moment, whereby the polarity of neighbouring
atoms is weakened or destroyed. Heat of vaporization consists in the vis viva spent or absorbed in removing the
chemical atoms to a greater mean distance beyond the
limit of maximum cohesive power, so that the centrifugal
force is balanced only by some external pressure. But
besides these varieties of heat, depending on the solid,
fluid, or gaseous structure of the whole body, there will be
another variety, an atomic heat, depending on the essential structure of the compound atoms themselves.  It will
be least where their monads are most compact, and greatest
when they are at greater intervals from each other.  The
laws of force being given, its amount may be easily calculated for every variety of arrangement of the component




110            ON MATTER AND ETHER.
monads. Thus with the law of the inverse fourth, if the
unit of vis viva be the velocity of one pair of monads
acquired in falling from infinity to the neutral distance, the
value for an atom of 9 monads in three triplets would be
16 nearly, and that for one cycle of 16, 100, leaving an
excess of 68 for the latent vis viva which would become
sensible heat, or molecular motion, when the cycle of sixteen passes by combination into the other form.
75. Another remarkable feature of oxygen is its wide
diffusion and great combining power.
Fluorine is the only element, of which some compound
with oxygen is not known. Now its atomic number is
numerically of the simplest kind, being formed by successive doubling only. The values, also, deduced from
its solid compounds and water, and from its gaseous density, have this very same ratio to each other. This singular feature occurs in no other gas but the vapours of
phosphorus and arsenic only. Again, there are thirteen
or fourteen metals with which it forms a sesquioxide.
Hence a suspicion may naturally arise, that a half atom
here enters directly into combination. In this case the
three numbers 4, 8, 16, formed by successive doubling,
would all belong to oxygen in these allotropic forms, and
serve to account for its immense combining power.
76. Allotropic Forms of Carbon.
Carbon, it has been discovered, admits of four allotropic forms. The first is the diamond, sp. gr. = 3'52 and
octahedral. The second graphite, sp. gr. = 217, and its
form the hexagonal prism. The third coke, sp. gr. = 1'89,
and its primary form a cube. The, fourth anthracite and
charcoal, sp. gr. = 1'773, and its form square prismatic, the
axes nearly as 5, 5 and 3. In the last form it is softer




CHAPTER VII.                  111
than coke, and a worse conductor of electricity.  By a
bright red or white heat it is changed to coke in its other
characters, but not in its specific gravity or crystalline
structure.  What light is thrown on these striking and
characteristic facts by the present theory?
First, the densest and most compact form in which
six monads can be disposed is the regular octahedron.
Now six is the atomic number of carbon, the diamond
its densest form, and an octahedral crystal. On this view,
also, the peculiar hardness and cutting power of the diamond are fully explained.  The apex of every atom  so
formed must form a molecular wedge, to penetrate any
surface to which it is applied. The shape of the ultimate octahedron must also reproduce itself, evidently, in
the cleavage of the whole crystal.
The second form, in graphite, has for its type the
hexagonal prism. Now if two cycles of six be superposed, we have clearly the first element of this very
form. The number of monads in such an atom will be
double those of the octahedron, but the area of the circumscribing sphere is 21/2 times greater, and the actual
area, when the two cycles are in their stable position, or! /3 their vertical distance, as 12: 24, or 1 to 4772.
2                              3
Hence the density must naturally be less in the hexagonal
structure, in a ratio between the limits 1'414 and 2'386,
but from the crystalline and diaphanous structure of the
diamond, much nearer the former limit. The experimental
ratio is 1'62 to 1.
77. The two other allotropic forms, in coke, and in
anthracite and charcoal, are the cubic and square prismatic,
the latter having one axis about three fifths of the others.




112            ON MATTER AND ETHER.
The latter is converted into coke at a white heat, retaining
otherwise its former structure.
Now if we suppose the two hexagons to be superposed exactly on each other, the double hexagons arranged
symmetrically at right angles in the same plane, and the
second tier also at right angles, but alternately in position, the height of each tier will be twice the neutral
distance, that is, once between the two hexagons, and a
half distance on each side. But the diameter, in each of
the two horizontal axes, will be twice the neutral distance
also. Hence it seems plain that the result must be a
structure of which the type is the cube, or the three axes
all equal.
Again, let us suppose a similar arrangement, with the
one difference that the two hexagonal cycles in the same
atom  are alternately arranged.  The vertical axis will
now be V/3 instead of 2, or in the ratio of 6 to 7. But the
external attraction of the neighbouring atoms will tend
doubly to enlarge this proportion, and may render the
third axis unequal in a still greater degree. On the other
hand, the application of heat, increasing the lateral repulsion, will tend to restore the atoms to the more vertical
and less compressed position.
78. Proj2erties qf Nitrogen.
Let us inquire what will be the characters of a cycle of
seven monads in the same plane. The radius of a heptagon, when the side is unity, is 1'152, and the reduced distance of equilibrium by the assumed laws is nearly 1'143,
and with an added central monad, 1'107. The distance
of equilibrium, with an ether monad in the centre, will
be intermlediate, or 1'12204 nearly. But the distance of
equilibrium for an ether monad itself is /2 = 1 122458s, or




CHAPTER VII.                 113
almost exactly the same with the former. It follows that
an ether monad will be in steady equilibrium in the centre
of such a cycle, but not one of matter; so that their affinity
for material monads must be greatly lessened by the repulsion of axial ether monads, which they will retain in
steady and permanent union.
The union of nitrogen with hydrogen seems to have
exactly the characters which would result from these mechanical conditions.  Carburetted hydrogen is resolved
only by a very strong heat, but ammonia is completely
decomposed by passing through porcelain tubes, heated to
redness. On the other hand oxygen and hydrogen have
no compound of a gaseous form, or without an entire
change of their separate properties by intense and violent
combustion. So axial particles, joined with a cycle of
six, will be in equilzbrio on each side of the centre, and
have a strong affinity to the radial particles. With cycles
of eight, they will be either unfixed and disconnected, or
exert a strong disturbing and decomposing power. But
with cycles of seven, they will neither admit, as in the
former case, of very stable union, nor exercise, as in the
second, a strong disturbing power. They will replace,
with some difficulty, ether monads already occupying the
axis with a relation of stability, and being united in a
less stable manner themselves, any considerable heat, or
atomic oscillation, may be expected to separate them again.
The electric spark, in a mixture of hydrogen and nitrogen, produces no union, while hydrogen and oxygen
explode violently. Iii ammonium the union of the two,
elements is so feeble, that it can only be maintained in
amalgam  with mercury, under a galvanic current, and
is resolved when the current is withdrawn.
8




114            ON MIATTER AND ETI-ER.
Again, there is a difference between the compounds of
carbon and nitrogen with hydrogen. One of carbon cornbines with two of hydrogen, and. conversely, and there
is a large number of hydrocarbons in which the number
of the atoms differs by one only. But the chief compound
of nitrogen and hydrogen is ammonia NITH, while the two
hypothetical compounds, amide NiTH2 and ammonium NH4,
never exist in a separated form.
Now a double cycle of seven, with three monads in the
axis, will have some degree of permanence, or be in a state
of imperfect stability. One monad will be midway between the cycles, and one on each side. But the limits
of stability being so narrow, from the near equality of the
radius to the cohesive limit, a change in the compression
or expansion of cycle, by union with other atoms, may
enable two to rest in equilibrio in the planes of the cycles,
or two in the planes, and one also on each side. These
effects follow naturally from the slight excess of the radius
above the neutral limit, and its exact coincidence with the
enlarged limit for ether atoms.
79. Nitrogen, in contrast to oxygen, does not sustain
combustion, and, on the other hand, can scarcely be called
combustible. Its compounds with oxygen are peculiar.
The Protoxide, by its density as gas, is oxygen 8 + nitrogen 14 = 22. Its Binoxide is lighter, and answers in
density to oxygen 8 + nitrogen 7 = 15. The former is a
general supporter of combustion, the latter only in special
cases.  Hyponitrous is NO,=38, nitrous acid N04= 46,.and nitric acid NO5= 54. The last is a powerful oxidizer,
and its presence plainly gives its explosive power to gunpowder, and to similar compounds of saltpetre.
Let us now conceive two single cycles, one of seven,




CHAPTER VII.                  115
the other of eight monads, to be associated together.
Their radii of equilibrium  will plainly be different, the
cycle of seven being less remote from the axis, as 1'12 to
1'26, or 8 to 9. But this difference will be lessened by
their union, which tends to contract the one, and expand
the other. Their numbers being prime to each other, there
can be no tendency to a fixed angular relation, but they
must act on each other nearly as two continuous circular
wires, and their axial distance be nearly /1 -'142='99, or
very slightly less than the neutral distance. Any increase of
vis viva will expand the larger cycle, while the other -will
be hindered from expanding by the central ether, and thus
the oxygen will easily combine with those substances
which have an affinity for that element.
Again, let us conceive one cycle of seven to be included
between two of eight monads. The contraction will be
greater than in the former case, from the greater number of
non-adjacent monads.  The second cycle of eight, by its
attraction for the first, will bring them  nearer than the
distance in the last structure from the middle cycle, which
will be repelled inward, and slightly contracted in size.
Hence, in case of combination with a combustible body,
there will be three causes of difference. A stronger connection will have to be overcome. The oxygen cycles, for
the same quantity, will have less atomic vis viva to part
with, and one portion of this will be absorbed by the
re-expansion of the nitrogen, when the new compound
leaves it free and separate. Accordingly, the binoxide
supports combustion in some cases only. " Burning sulphur
and a lighted candle are extinguished by it; but charcoal
and phosphorus, when in vivid combustion, burn with
increased brilliancy."
8-2




116            ON MATTER AND ETHER.
These explanations, of course, are in some degree provisional, and may have to be modified, when the theory
is more fully developed, and applied by the help of a
strict analysis, to determine the relative stability and inherent vis viva of different cyclical combinations.  It
would be premature to attempt their extension to conjectural arrangements for the more complex compounds of
oxygen and nitrogen. It is enough to justify a general
confidence in the present theory, that it gives results, even
at first sight, in singular harmony with the distinctive
characters of these four leading elements, and of some of
their simplest compounds.
80.  Carbon and Nitrogqen.
These two substances form one principal compound,
Cyanogen, which has many of the properties of chlorine
and other simple bodies. Its formula is C2N. It is a
colourless gas possessing a strong pungent and peculiar
odour. Under the pressure of 31 atmospheres it becomes a
limpid fluid. It extinguishes burning bodies; but is inflammable, and burns with a beautiful purple flame. Its
density, that of hydrogen gas being one, is 26, or nearly
double that of atmospheric air. Paracyanogen is an isomeric substance, but solid, with a probable compositions
C8N,. Cyanogen has a remarkable tendency to combine
with elementary substances, and with metals rather than
their oxides.  Fulminic acid, the basis of fulminating
silver, is Cy2O,. Hydrocyanic gas is formed from equal
measures of hydrogen and cyanogen, and like the similar
compounds of hydrogen with chlorine, bromine, and iodine,
the bulk is not altered by the combination; so that its
atomic weight as a gas, hydrogen being one, will be 131,
or a fractional value. Its properties are highly poisonous.




CHAPTER VII.                  117
It decomposes easily under the influence of light, but
small quantities of acids hinder the decomposition. Cyanogen is obtained at a low red heat from the bicyanide of
mercury. The affinity of Palladium for this element surpasses that of all other metals.
Now let us suppose that cyanogen consists of two
carbon cycles of six, and two nitrogen cycles of seven,
blended into two composite cycles of thirteen monads. Its
basis, then, will be another prime, distinct from 3, 7, those
of its components, and from 2, the prime basis of oxygen.
Being dual, its symmetry will contribute to its permanence. But in all the more subtle relations which have to
do with odour and electric harmony, when compared with 6,
12, 8, 16, the usual and frequent cyclical numbers, or 7, 14,
those of nitrogen, it will have the same analogies as a
musical discord. It will combine with metals as a simple,
like oxygen, chlorine, iodine, and bromine. But in combinations with compound atoms of low cycles, it will tend to
resolve itself, by a nearly equal division, into its component
nitrogen and carbon cycles. Its atomic number 26, and
that of Palladium 53'3, have very nearly the ratio of 2 to
1; and this may possibly have some connexion with the
strength of its affinity for that metal.
81. Thus a review of the leading characteristics of
the four simplest elements, hydrogen, carbon, oxygen, and
nitrogen, and of their simpler and more fundamental compounds, reveals in every case numerous and striking agreements with the primd facie results of the present theory.
These are the elements where, above all the rest, we might
expect to find a key to the real nature of the atomic structure. Their wide diffusion, their integer ratios to each
other, the specific characters and universality of water,




118            ON MATTER AND ETHER.
their simplest compound, all invite us to some explanation
which shall strip their properties of an arbitrary, empirical
character, andc reveal them  as the distinctive and natural
results of their derivation from some simple and universal
form of matter. But other elements, and many other
classes of phenomena have to be examined, before the competency of the hypothesis can be fully tested, and a clear
warrant provided for submitting it to a more profound
analytical investigation.




CHAPTER VIII.
GENERAL RELATIONS OF THE CHEMICAL ELEMENTS.
82. THrE  Electrolytic order of the elements differs
widely from that of their atomic weights. They may be
thus distinguished into successive groups, as follows:
1. Oxygen, sulphur, chlorine, bromine, iodine, fluorine, nitrogen, phosphorus, selenium.
2. Arsenic, chromium, molybdenum, tungsten, boron,
carbon, antimony, tellurium, tantalum, titanium, silicon,
osmium, hydrogen.
3. Gold, iridium, rhodium, platinum, palladium, mercury, silver.
4. Copper, uranium, bismuth, tin, lead, cerium, cobalt, nickel, iron, cadmium, zinc, manganese.
5. Zirconium, aluminium, yttrium, gluciniunm, magnesium, calcium, strontiumn, barium, lithium, sodium, potassium.
The contrast between this electrolytic order, and that
of atomic weight, is very conspicuous.  Hydrogen and
gold, the lightest and heaviest atoms, meet here in the
middle of the list.  Chlorine 36 and potassium 39, fluorine 19 and calcium 20, which are very near in atomic
weight, are found at or near the two extremes.




120            ON MATTER AND ETHER.
On the present theory the atomic numbers must depend
on the relative number of monads which compose each
atom, and the electric order on their radial or axial arrangement. For the positive pole of the electric current
must be conceived to represent a superior velocity of atomic
rotation, or greater vis viva, and the elements which tend
to that pole or electrode must be those which have the
greater moment of rotation, or a less axial and more radial
structure.  Hydrogen, of the simple monads, must be neutral in this respect, or claim a middle position. The
regular metals must be supposed, from their cohesion, to
be slightly or strongly polar; and the precious metals
which are least oxydizable, to come near to hydrogen with
regard to equality of moments, which is indicated also in
mercury by its great fluidity.  Atoms of nearly equal
weight, if they come near the extremes, may be expected
to have contrasted properties, but when they come near
in the series, to have a close resemblance. Thus cobalt and
nickel, which are near iron in both respects, are also magnetic and hard metals.  But chlorine and potassium, fluorine and calcium, which have their atoms nearly equal in
weight, but at opposite ends of the scale, have a strong
and peculiar affinity for each other. It is clear that a
hollow atom, of few cycles and large radius, and one of
more cycles and small radius, may combine radially by
the contrast of their characters, and an intense evolution
of vis viva or'ethereal motion must result fiom  such a
union.
83. The gaseous and vaporizable elements, except
hydrogen, occupy the foremost places in the electric scale.
The exception is explained at once, if hydrogen represent
the simple monad, which must be indifferent with regard




CHAPTER VIII.                    121
to axes of rotation.  The others must answer to hollow
cycles, maintained by centrifugal force in stable equilibrium,
and therefore not easily susceptible of a solid structure.
If we assume 16 or 2'8, 2'16 or 4'8, 2'18 or 3'12, 4'20, 6'21,
19 or 8 + 9, and 14 or 2'7 to represent the arrangement of
these high electro-negatives, their electric order will have a
probable explanation, along with their atomic weight, and
there may be thus some near approach to a just definition.
Such elements, by their structure, must be capable of
combining radially with those of a small circuit, and will
set loose central ether, and an answering amount of v's
viva or atomic heat, by such a union.
84. The next class, in which the electro-negative character prevails, includes carbon, boron, and silicon, and nine
acid-forming elements. Carbon has been already examined,
and the nature of its atom  conjecturally defined.  Let us
consider boron and silicon separately, and the other nine
elements.
The atom of boron, according to Berzelius, is 5'5724, or
doubling, 1 11448; but according to Turner, Fresenius, and
Fownes, 10'9. The mean of these is the integer 11, which
may claim  to be the true value.  It is a prime number,
and its simplest division is 6 + 5, where 6 is the atom  of
carbon, and five a factor of calcium = 20, and probably of
several other earth-forming metals.
The properties of boron are very peculiar.  It is a dark
olive-coloured substance, a non-conductor of electricity,
insoluble in water, alcohol, ether, and oils. It bears intense
heat in close vessels, without fusing, or any change but a
slight increase of density.  Its spec. gr.= 2 nearly.  If
heated to 600~ it takes fire, and boracic acid is generated.
Boracic acid is a solid hydrate, spec. gr. = 1'479, and is




122             ON MATTER AND ETHER.
rather bitter than acid, reddens litmus paper feebly,. but
renders turmeric paper brown like the alkalies.  All the
borates, ill solution, are decomposed by the stronger acids.
Anhydrous boracic acid is a hard, colourless, transparent
glass.  One of the strongest affinities of boron is with
fluorine.
The characters of boron are thus intermediate between
those of carbon and the bases of the earths. Like carbon,
it is a dark, unmetallic solid, and forms an acid by its
union with oxygen.  On the other hand, its oxide is solid
and not gaseous, and has some resemblance to silicon, as a
glassy substance, imperfectly soluble.  Now if we conceive
it to be formed of two cycles, one of six and the other of
five atoms, it will be half carbon, half earth, assuming a
cycle of five to be the typical character of the earth-forming bases. Again, it has a special affinity with fluorine, as
shewn by the formation of fluoboric acid gas.  But the two
primes 11 and 19 are not only both exceptional to the
series of composite numbers, but differ by eight, so that
the larger may readily include the smaller, with a distance
slightly exceeding the neutral distance  between  them.
Such a relation will be one of strong cohesive affinity. On
the other hand, the resolved cycle of six and five will explain the characters of boracic, as intermediate to those of
carbonic and silicic acid, and the double relation of boron
itself to carbon and silicon.
85. Silicon or silicium, in its oxide silica, is one of
the widest diffused and most universal of substances. We
should thus infer, on the present hypothesis, that its structure must be one of great simplicity.  It is the base of an
earth, but much higher than the other earth metals in the
electric scale, so that silica has the functions of an acid,




CHAPTER VIII.                  123
and forms silicates of the alkalies and earth oxides. The
element seems also to be dimorphous. " It is a dark brown
powder, destitute of lustre. When strongly heated in a
covered crucible, its properties are greatly changed, and
it becomes darker in colour, denser, and incombustible."
The equivalent of silicon has been variously reckoned,
by Thompson at 7'5; by Berzelius (Miller) 2371, by Turner
22,5, by Fresenius 14'79, and in Fownes and others at 21'3.
Their differences arise mainly from a varying conception of
the composition of silica, whether it is a protoxide, dentoxide, or teroxide. According to these three hypotheses, and.
the two different estimates of the ratio of the parts in
silica, the values will be 22'5 or 21'3, 15 or 14'2, and 7'5
or 7'1. In this diversity, and considering the uncertainty
of the argument friom the number of atoms in similar compounds, which is contradicted by the isomorphism of potass
and hydrated ammonia, the liberty may be claimed of
selecting the most probable value on internal grounds, or
from the requirements of the present theory.
Let us assume, then, the true value to be 15 = 3'5, and
we shall have three cycles of five for a probable form. This
may plainly exist in two forms at least, as the cycles are
exactly superposed, or the radii of the middle cycle alternate
with the others, so that the height is diminished nearly as
/3  2.  The radius of a pentagon is.8506, and of inscribed circle'688, the side being one. If two cycles were
radially superposed, the particles being doubly intermediate, the radial distance of those at neutral distance from
the two nearest monads in each of the two adjoining cycles
will be, apart from  the general compression,'688 +707
= 1'395. But the unreducedl radius for an octagon, or cycle
of eight, is 1'307. Hence two cycles of eight, superposed




124            ON MATTER AND ETHER.
radially to three cycles of five, will have a position not
far remote from one of neutrality, or, in other words, of
maximum stability.
Again, fluorine has a strong affinity for silicon, as for
calcium. But if a cycle of 19 is brought near to a triplet
of cycles of five, any common revolution must tend to
decompose the former into two portions, nearly equal, of
10 and 9, the former of which will be susceptible of being
superposed symmetrically to the others, while the nine will
also be superposed, but so as to produce a double want of
symmetry.
The density of silica is 2], which would answer to 24,
if its atoms are compressed in the same degree as those of
water. Its atomic number, on the present supposition,
would be 31. Also, if a cycle of 5 be the typical feature
of earthy bases, then silicon, if composed of three only,
would be the simplest of them, and the highest in the
order of electric arrangement.
86. The nine metals which belong to the same class,
as most electro-negative, are these.
Arsenic 37'5 or 75, chromium 28 or 26'7, molybdenum
46, tungsten 92, antimony 64'5 or 129, tellurium  64, tantalum 92 or 184, titanium 24'1 or 25, and osmium 99'6.
All of these agree in some common properties. With
oxygen they form the arsenious and arsenic, antimonious
and antimonic, chromic, molybdic, tungstic, telluric, tantalic, titanic, and osmic acids. To these may be added
vanadium, forming vanadic acid. Arsenic, antimony, and
tellurium  also combine with hydrogen, a very unusual
feature in metals. Arsenic is distinguished by the poisonous properties of its oxide, and the quality of subliming
without being capable of fusion.




CHAPTER VIII.                   125
All these features point to the general conclusion, that
these metals have no axial or central monads, that they
have only three cycles, or four at most, and two radial
sets of monads at least in each cycle, and have thus
affinities with oxygen, chlorine, &c. by their outer shell,
and with hydrogen by the inner, or the want of axial
monads, while their flat structure, or large radius compared with their height, renders them more susceptible of
volatilization than metals inr general.  Silicon, in electric
order, has the lowest place in this class, and perhaps it
may be inferred that no cycle of less than six enters their
composition.
87.  The third and middle class, in electric order, consists of gold and silver, the precious metals, of mercury,
the only fluid metal, and of platinum, iridium, rhodium,
and palladium, all found in the same ores, each pair having
nearly the same equivalents, and also of great hardness
and density.
The equivalent of gold, in Berzelius, is 198'9, in
Turner 199'2, in Fresenius 196'5, and Fownes 197, or the
estimate varies nearly from 196 to 200. That of mercury
is 202'5 Berzelius, 202 Turner, 200 Fresenius, 100 Fownes,
where the frequent ambiguity appears between the single
or double value, and if the larger be taken, the atoms of
gold and mercury are very nearly the. same. In like manner Platinum is 97'2 Berzelius, 98'8 Turner, 98'7 Fresenius and Fownes; and Iridium 98'8 Turner, 98'6 Fresenius,
and 99 Fownes.  Here the difference in the estimates of
the equivalent of the same metal is greater than their
difference from each other.
Again, Rhodium is 120 Berzelius, 52'2 Turner, Fresenius, and Fownes; and Palladium  112'6 Berzelius, 53




126            ON MATTER AND ETHER.
Fresenius, and 53.3 Turner and Fownes, a third instance
of very near approach in the equivalents, as they result
from the latest inquiries.  Silver is reckoned by all authorities at 108, with hardly a variation.
The characters of these metals agree with the hypothesis of a somewhat cubical structure of their atom, with
factors not very unequal, and probably rounded off, at
least in mercury, into a nearer approach to the sphere.
It is conceivable that the variation of one or two units in
their estimated equivalents may arise from a real latitude
in their structure, or that some of them exist in allotropic
forms, slightly diferent, and depending on the presence
or absence of one or two material monads, and their
replacement by monads of attached ether.
88. Let us begin with a perfect cube, with six for
its side, which would contain 216 monads.  The pressure of the whole, excepting the corner monads, and any
centrifugal force, will maintain the relief of the edges, and
expose them to possible abrasion.  Let us suppose the
two terminal planes on each side to lose their corner monads, and the two central ones to retain them, the compound atom  will consist of 216-44 = 200 component
monads. If the corner atoms are again removed from one
corner only of the two central planes, the number will be
198, if from two corners, 196. In other words, there will
be an atom composed of four planes of 32 and two of 34
monads. Such may possibly be the structure of the atom
of gold.
Again, let us take the cube with five for its side, or
125 monads. Let us suppose the middle plane unchanged,
the two next deprived of their corner atoms, and the terminal planes reduced to a square of nine, with two atoms




CHAPTER VIII.                  127
added symmetrically on each of its four sides. TWe shall
then have a compound atom of 25 + 2'21 + 2'17 = 101 monads.  This regular bevelling of a form, fundamentally a
cube, must evidently tend to produce fluidity, by destroying all polarity, and making it easy to vary the axis of
rotation, and for the atoms to approach one another equally
on every side.  But 101 is the earlier estimate of Turner
and Berzelius for the atom of mercury, and that metal is
distinguished from every other by its fluidity at all common temperatures. A compound atom, such as has been
just described, appears to satisfy these conditions.
89.  The atoms of Platinum  and Iridium, in Turner,
are both 98'8, in Fresenius 98'68 and 98'56, and in Fownes
98'7 and 99. There is thus no well ascertained difference
between them.  Platinum is the densest of known metals,
ranking in this respect higher than gold.  It is also much
more tenacious, and is nearly infusible.  If we conceive
five planes or cycles to be formed, each of two intersecting
squares of four, or a square of 16 monads, with another
monad symmetrically added on each side, we have a compound atom of 100 monads. Or again, if four such cycles
have a square of nine added on each side, we have a symmetrical atom of 98 monads.
The atom of silver is 108, which might be formed by
three planes, each a six-sided square, or by six four-sided
squares, with a monad on each side between every pair of
cycles, so as to give a nearer approach to a cylindrical
form. Assuming, however, the truth of the general hypothesis, it is only by degrees, and after full investigation of
the results of each arrangement, that we can reasonably
hope to attain, for each element, a certain knowledge of its
exact atomic form.




128             ON MATTER AND ETHER.
90. The next class includes the more oxidable proper
metals, copper (63'3, 31'6, 31'7), uranium (217, 59'4, 60),
bismuth (141'9, 71, 213), tin (117'6, 57'9, 58'8, 58), lead
(207, 103'6, 103'56, 103'7), cerium  (92, 46, 47'26, 47?) cobalt (59, 29'5, 29'5, 29'5), nickel (59'2, 29'5, 29'5, 29'5),
iron (54'3, 28, 28, 28) cadmium (1115, 55'8, 55'8, 56), zinc
(64'5, 32'3, 32'5, 32.6), and manganese (56'9, 27'7, 27'6, 27'6),
with their equivalents from Berzelius, Turner, Fresenius,
and Fownes.  Most of these decompose water at a red
heat, and are oxidized.  Iron is strongly magnetic, and
cobalt and nickel come nearest to it in that quality, while
bismuth is first in order of diamagnetic substances.
The natural conclusion, from the relative electric order
of these elements, and their affinity for oxygen, is that
they are more prolate in figure than the previous class;
though the diamagnetic properties of bismuth and others
may require, in their case, some modification of this view.
There is also the serious doubt, in most of the metals,
whether a single or double number is the truer value; especially since the best estimates for cobalt, nickel, and copper, have for their apparent unit the half hydrogen atom.
The most important of these elements is iron, and the
integer value 28 is assigned to its atom by a general consent of the best analytical chemists. This has the same
relation to nitrogen, which that of sulphur bears to oxygen,
or is exactly its double.  The wide diffusion of the metal,
and its strongly characteristic properties, would seem to
require a simplicity and symmetry in the structure of its
atom, beyond those of rare occurrence. The number is composite, and resolves itself only in one way, or into four
sevens. Let us suppose four cycles, each composed of a
hexagon and one central monad, and we have plainly a




CHAPTER VIII.                   129
very simple and coherent structure.  The seven atoms in
each cycle are in the densest possible arrangement, and
would be all at the neutral distance, except for the slight
cohesive force exercised on each radial atom  by the three
which are most remote. The horizontal axes will be equal,
and slightly less than 2, and the vertical axis -either -3 or
2'6, according to their vertical or alternate superposition.
The atoms will thus be polar, strongly tenacious, susceptible of easy revolution round the central axis, by which
they will assume magnietic properties. The nearest affinity
will be with carbon, of which the cycle is six, and with
which iron is known to have a very powerful affinity.
91.  The last class, in electric order, includes zirconium, aluminium, yttrium, glucinium, magnesium, calcium,
strontium, barium, lithium, sodium, potassium, or the metallic bases of the earths and alkalies.  These are all
strongly electro-positive, but the bases of the alkalies still
more than those of the earths. Zirconium, yttrium, glucinium, strontium, barium, lithium, are comparatively rare;
but aluminium, nmagnesium, calcium, sodium, and potassium, are substances, in their oxides, very widely diffused.
Now it is plain that, if radial or axial arrangement is
the basis of the electric relations of a compound atom, a
cycle of six forms a kind of limit between two opposite
kinds of structure, since the radius and the side of tle
hexagon are equal.  Cycles of five and four constitute two
successive stages of a centrical arrangement, the converse
of that which belongs to the gaseous and volatile elements.
One of these elements, which is most widely diffused,
and which is almost like a link between the earthy and
alkaline batses, is calciumn, for lime has strongly alkaline
properties.  Its equivalent, by general admission, is pre9




130            ON MATTER AND ETHER.
cisely 20 times that of hydrogen.  This suggests immediately the two alternatives of four cycles of five, or pentagons, or of five squares. The former may perhaps be
assumed as its probable structure.  Its oxide, hence, may
be conceived as having a cycle of eight radially superposed
between its middle cycles.
Again, magnesium has its atom reckoned variously at
25'34 Berz., 12'7 Turner, 12'62 Fresenius, and 12 Fownes.
Assuming here the greater correctness of the earlier estimate, and taking the double value of Berzelius, we have
25 for the atomic number, or five times five.  On this
view  Silicon=3'5, Calcium =4'5, and Magnesium=5'5,
would form a progression of simply constituted elements.
92. Sodium and Potassium  are the metallic bases of
the two alkalies, and come last in the electrolytic order of
the elemnents.  They are among the lightest solids, being
both of them lighter than water, and are oxidized by it
with strong. combustion. Both their electric place, and the
alkaline character of their oxides, imply in them some
atomic feature which contrasts strongly with oxygen,
chlorine, and the electro-negative sustainers of combustion.
Now the character of these, on the present theory, is excess
of latent vis viva, or a structure at once compressed at the
circumference, and hollow in the centre, so as to admit,
when the cycle is broken up, or combines with other
atoms, of a much more compact and condensed arlrangement. The opposite character must be a condensed structure, with repulsive force from the centre, and attraction
laterally at the surface.
Let us consider Sodium first, as the element of
smaller atomic weight.  Its number, in earlier estimates,
is 23'3, and in the later simply 23.  Let us first con



CHAPTER VIII.                 131
ceive cycles of four monads vertically superposed.  They
will be in egquibrio, when the side of each cubic space
is slightly less than the neutral distance.  Now  let
four monads be introduced centrically into those spaces.
They will be at the distance 1 /V3 from all the enclosing
monads, and the excess of repulsion 3- times the balanced
repulsion at the neutral distance.  Hence the planes
must expand laterally, till they reach nearly the value
I -= 1225, being hinldered fiom vertical expansion by
the cohesive force towards each other of the central monads.
We shall thus have a compound atom of 24 monads, reversing the conditions of the gaseous cycles, an excess of
repulsion between the centre and the edges being compensated by the attraction of the superficial monads, thrust out
from  each other beyond the neutral distance.  In the
absence of other matter, ether particles in excess must clothe
the sides of such an atom, as they must occupy the line
of the axis in gaseous cycles; and these opposite relations
must produce a strong affinity. The properties will probably be nearly the same, if the terminal central monads
are attached outside the first and fifth cycles, instead of
within them. It is conceivable that there may be three
allotropic forms in which there are four central monads
within, two central and two attached, or two central only,
in which case 23'3 would be the resulting mean value
of the atom.
Another curious relation comes to light on this hypothesis. An atom of sodium, on this view, would have five
spaces, each exactly resembling an atom of water, or would
be 2-1 atoms of water completed into unity and symmetry
9-2




132            ON MATTER AND ETHER.
by an atom and half of hydrogen axially combined.  Such
a union may be conceived to be the result of strong and
intense pressure.  Now two facts are remarkable, that
the salts of sodium  are all remarkable for their great
solubility; and the ocean and deep seas, where water is
exposed to great pressure, all are impregnated with common
salt, or chloride of sodium, so as to form one constant
and invariable constituent.  There is here a simple and
natural explanation offered of this striking phenomenon.
The atomic number of Potassium is 39. Let us conceive eight instead of five cycles of four superposed, and
seven axial monads introduced.  We have then a structure
precisely similar to that of sodium, but still more axial
in its character, so as naturally to exceed sodium in its
electro-positive character.
93. A striking fact in chemistry, which has caused
much  perplexity, is the isomorphism  of the  salts of
hydrated ammonia with those of potass and soda, and
tihe ammoniacal amalgam, of which one component, the
am monium, or hydurate of ammonia, cannot subsist alone.
On the supposition that all our present metals are really
simple, this fact is a great anomaly; and the conjecture of
some, that nitrogen is a metallic oxide, merely increases
the difficulty, for it is NH4 or nitrogen with four atoms
of hydrogen which answers to one anhydrous atom  of
potassium or sodium. On the present view, the analogy
comes clearly to light. The nitrogen, in ammonia, may
be conceived:as two cycles of seven, with which three
atoms of hydrogen are axially combined. The hydrate will
add to these two cycles of four, and one axial atom, so as
to form a compound atom, with two cycles of seven, two of
foulr, and four central or axial atoms of hydrogen.  But the




CHAPTER VIII.                 133
oxide of sodium may probably consist of two quaternions,
superposed radially between the second and fourth constituent cycles.  The number of axial monads will thus be
the same. The cycles will be four in one case, and five
in the other; and the radius of the cycle of seven and the
superposed cycles of four, in the sodium, will have nearly
the same ratio as the length of the two axes. But the
central particles, in one case, will be inseparably joined
by a strong repulsion, due to the contractile tendency of
the fourfold cycles; while the other will separate easily,
under heat, because of the expansive tendency of the
cycle of seven, which is at equilibrium only when its
radius exceeds the neutral distance.  It seems unlikely
that so many correspondences, growing out of the present
hypothesis, even in its undeveloped form, should not be
indications of its substantial truth.




CHAPTER IX.
ON STATICAL ELECTRICITY.
94. THE Science of electricity, of late years, has
received an immense development, and linked itself with
every part of Physics, but its theory remains perplexing
and obscure. Three cldierent hypotheses have been proposed, and none of them  can be viewed as satisfactory:
the one electric fluid of Franklin, with the recent additions
of Mosotti; the two fluids of Symmer, with the developments of Coulomb, Poisson, and Miurphy; and the induction theory, or lines of forces, of Faraday and other eminent electricians.  It will be cofnvenient to state, first of
all, some of the leading facts, and then to remark on the
proposed explanations.
(1)  All bodies, by friction or other means, are capable of receiving some modification of their surface, which
is called an electric charge.
(2) The electric charge is of two distinct kinds, positive or vitreous, and negative or resinous, and when one
surface is excited positively, the other is excited negatively.
(3)  Surfaces charged with like electricity, repel each




CHAPTER IX.                    135
other, and chargecl with unlike electricity, attract each
other, with a force varying nearly or exactly, as the square
of the distance.
(4) Some substances are conductors, and allow a
charge to distribute itself easily over their surface, and
others are non-conductors, along, which it spreads very
slowly and with difficulty.
(5)  A  charged surface tends to induce an opposite
state on a surface opposed to it, or vitreous, to excite
resinous, and resinous vitreous electricity.  This tendency
is exerted, not only across air or a vacuum, but solid insulatingo or non-conducting bodies, called in consequence
dielectrics.
(6)  Strong charges of opposite kinds neutralize each
other through the air, or a!conductor, by an electric spark,
aflter which both bodies are neutral, or lose the signs of
electricity.
(7)  An electric charge diffuses itself over a conducting body, so as to be wholly at the surface, but densest
at points, edges, or where the curvature is most abrupt.
(8) Electricity is developed in all chemical action,
and may be thrown into a current, passing continuously
between two opposite poles or electrodes.  In this form
it has power to decompose chemical compounds, and electro-negative elements appear at the positive, and electropositive elements at the negative poles.
(9)  Electric currents, in mlottion, attract each other,
when they are parallel, at right angles to the line joining
them, and repel each other, when moving in the same
direction in the lines of the centres.
(10)  Electric currents in motion, disposed in spirals,
have all the properties of natural magnets, and natural or




136            ON MATTER AND ETHER.
artificial magnets share the properties of spiral electric
currents.
95. The theory of Symimer, Coulomb, and Poisson
assumes the existence of two electric fluids, each selfrepulsive, but attracting the other, diffused in equal quantities through all matter, so as to be in a neutral state.
These fluids are conceived to repel and attract by the law
of the inverse square, but to have no direct influence upon
the matter with which they are associatedl, and to be
detained at the surface of conductors, either by the pressure
of the air, or some cause not yet known.
The remarks of De la Rive shew the growing distrust of
this hypothesis among scientific electricians.  "We shall
not discuss," he says, " the comparative merits of these
two theories (of two or one fluids). The latter, in such
sort as Franklin formularized it, cannot be admitted, we
shall see presently for what reasons. The former, although
subject to strong objections, is in the present state of
science a very convenient and tolerably exact manner of
representing this agent, that we term  electricity.  We
may for the present say, it is very probable that this
electricity, instead of consisting of one or two special fluids
sui generis, is nothing more than the result of a particular
modification in the state of bodies.  This probably depends on the mutual action exercised on each other by the
ponderable particles of matter, and the subtle fluid that
surrounds them on every side; a fluid generally known by
the name of ether, and the undulations of which constitute
light and heat."  And again, " What is this fluid, which
undergoes these modifications?  Here, we confess, are
questions not resolved, and we are far from presenting the
theory of the two fluids as the limit to our knowledge.




CHAPTER IX.                   137
Further on, we shall see that electrical phenomena very
probably depend upon the combined action of matter,
and the ethereal fluid which fills the universe; and by
thus approaching to Faraday's molecular theory we shall
be nearer the truth, than with the hypothesis of two imponderable fluids, existing of themselves, and in a manner
independent of bodies."
The objections to the theory of two fluids are palpable
and numerous. First, it is complex and unnatural to suppose two such substances, alike in everything but in the
sign of their action, diffused through all the universe in
exactly equal proportions.  Secondly, electrical phenomena
are thus isolated from those of light and heat, with which
they have the closest intimacy. Thirdly, the relation of
electricity to ponderable matter is thus wholly unexplained.  Fourthly, the excitement of electricity, or separation of the two kinds, under the hypothesis, is inconceivable. For their attraction, by the law of force assigned them, must be infinite when they are neutralized.
Fifthly, their retention in. vacuo is also unexplained.
Sixthly, the universal presence of electrical excitement in
chemical union and separation, the most important feature
of modern chemistry, is also left without any solution.
The agreement of the two-fluid theory with experiment, in the few cases where it can be tested, is far from
being so complete as some have urged. It has rather the
air of an imperfect approximation, than a full solution.
Thus (Enc. Metr. c. II. p. 139) the ratio of electricities on
two spheres which have touched and been separated, when
the radii are 1 and 2, 1 and 4, and I and 8, is by observation 1'08, 1'30, 1'65, and by the theory of Poisson 1'1601,
1'3168, 1'4443.  The actual difference is considerable in




138             ON MATTER AND ETHER.
both extremes. But, what is still more important, the law
of change is quite different.  The ratio of the extremes is
2: 3 by experiment, and only 4: 5 by calculation; and
this experimental value, when the radii are as 8 to 1, is
greater than the theory assigns to the case where the disproportion is infinite.
96.  The Theory of One Fluid, as recast by Miosotti,
has met with favour from  other writers.   It assumes three
laws of action, all as the inverse square, of matter on matter, matter on ether, and ether on ether. The first and
third are supposed to be repulsive, the other attractive, but
the last two to have a constant slightly higher in its value
than that of the first.  It is assumned, further, that the
molecules of matter have a solid and spherical form, upon
which the ether presses; that the quotient of the repulsion
of ether on ether at the unit of distance is immensely
greater than its elasticity.for the unit of pressure; that the
elasticity varies as the square of the density; and that tile
relation of the density of the ether to the molecular actions
is linear, and is the sumn of the densities they would separately induce at that part of the medium.
These assumptions, it appears to me, are quite inconsistent with each other. A density varying as the pressure
implies a repulsive force inversely as the linear distance.
This law obtains for gases where the elasticity is due to a
centrifugal force, but cannot possibly belong to a medium,
in  which the law  of repulsion is the inverse square.
Ai. Mosotti virtually assumes that distant parts of the ether
repel each other by a law wholly different from that which
lie ascribes to each separate portion. The constant of
force, also, in the distant action, is assumed to be immensely greater than for the contiguous particles, the force of




CHAPTER IX.                   139
which must chiefly determine the actual arrangement.
Again, the supposition that the elasticity is as the square
of the density contradicts the fundamental law of force,
which infers a connection between them of a very different
kind.  For all these reasons the memoir in question, however skilful as a piece of abstract analysis, is in my opinion
quite fallacious. The mathematical skill of the author has
led his readers to overlook the inconsistency between the
various assumptions on which the truth of the conclusion
must depend.  The explanation, also, of gravitation, by a
slight difference between the positive and negative constants in two laws of force precisely similar, has a very
arbitrary appearance, most unlike the simplicity and grandeur of natural laws. The admission of solid atoms, at the
surface of which the repulsion is infinite, is a further departure from all the proved -analogies of modern science.
97. The view of Faraday is widely different, and one
of which it is not easy to form a very distinct idea. It
lays down the principle that " an absolute electric state
cannot exist in a body, but that every electrized body finds
near it, either in insulating or conducting bodies, an opposite electric state to its own, which makes induction a
general phenomenon."  The general nature of the view
seems to be the substitution of equal lines of forces radiating in all directions from electrical surfaces or magnetic
poles, for definite central forces, decreasing by a fixed law;
and the decrease as the inverse square is viewed simply as
the result of the laws of space, or the fewer lines intercepted, when a body, finite in dimensions, is removed to a
greater distance.
So far as this hypothesis would resolve electrical attractions and repulsions into secondary results, and not




140             ON MATTER AND ETHER.
primary laws of central force, it agrees with the view to be
presently unfolded, and only seems rather wanting in a
clear explanation of the primary laws on which they must
depend. So far, also, as it refers electrical or magnetical
changes to the interception of lines of equal force, it agrees
with the necessary consequence of mutual action in a
highly repulsive ether.  But when it seeks to dispense
with the conception of central force altogether, even in the
case of gravitation, it appears to me to reverse the true
direction in which we are to seek for a clear and -satisfactory key to the great problem of electrical and chemical
change.  The view here proposed will have at least this
presumption in its favour, that it is almost intermediate
between Faraday's view of molecular induction, and lines
of force, and the earlier and more widely received fluid
theories. It is time now to proceed to its direct development.
98.  To ex2paci the presence of Free Electricity at the
surface of bodies.
The mean distance, in space, of the ether monads, it
has been shewn to be probable, from the velocity of light,
is not much greater, if greater, than the First Constant, or
the distance at which two units, or double atoms of matter
andl ether, would be at rest by their one repulsion and two
affinities.  The force of gravitation, in these cases, is relatively so small that it may be neglected.  The neutral
distance, however, as reduced by the ethereal pressure,
must in either case be less than the Ether Constant. Any
ntuhiber of units, joined together under the influence of this
pressure, or not separated by uncombined ether, may be
conceived to form a chemical atom.  The ether, which
penetrates solids and fluids, will isolate these chemical




CHAPTER IX.                   141
atoms from each other, and transmit the external pressure,
so as to condense them also, while it will be modified in
turn by their repulsion and cohesive affinity. The cohesive action between the different chemical atoms will be
exercised, in part, on their component units or atoms, but
more strongly on the monads of ether which lie between
them, and which must be fewer in the dense metals, and
more numerous in lighter bodies.
Every chemical atom, with its ether coating, thus contains in its essential structure a threefold bipolarity.  It is
composed of strongly attracting units or material atoms,
and strongly repulsive monads of ether. When in rotation,
it has a centrifugal action at its equator, and rest and
attraction on the line of its axis; and *its two poles have
themselves opposite characters, determined by the direction
of the rotation.  The first has a close analogy with the
phenomena of static electricity, the second with electrodynamics, and the third with magnetism.  At the same
time they are all most intimately related to each other.
Centrifugal action agrees with attached ether in its repulsive power, so that one can mechanically replace the
other; while the nature of the poles depends entirely on
the same fact of atomic rotation.
The interior strata of such a solid body, below the
depth where cohesive force is sensible, are under forces
symmetrical on both sides. With a few superficial strata,
and chiefly with the outmost, the case is different. On one
side are strata of matter, and on the other mainly of free
ether. This must therefore be condensed upon the surface by the whole amount of the affinity exercised by these
outer atoms.  The effect must be that, in contrast with
the inner strata, they will all be positively electrized,




142             ON MATTER AND ETHER.
using the term  conventionally for a surcharge of ether.
The greater part of the natural charge of each atom will.
be repelled to the inner side, and replaced by a larger
surplus on the outer side.  A few of the nearest strata will
experience, but in a lower degree, the like change, which
will bee limited by the rapid decrease of the affinity for
more distant ether.
The amount of this surcharge of ether must depend,
in ordinary cases, on the structure of the body, the mechanical state of its surface, the general temperature, and the
conditions for equilibrium of ethereal reaction in every set
of opposed bodies. For each kind of body, at the same
temperature, there will be a mean value or rate of ether
thus attached to the unit of surface.  Bodies in this
state, though their surfaces are positive with reference to
their interior strata, are neutral to each other, and will give
no sign of electric excitation. But if by any means this
mean or natural charge of ether is increased or diminished,
a new and distinct class of phenomena will arise. If any
separate units of matter are attracted to the surface, they
will increase still further its condensing power.
99.  To account for the excitement of electricity by
fraicton.
This fact, in which the science had its origin, needs
first to be explained by a true theory. The double fluid
hypothesis throws no light on it whatever.  On the
present view there is a simple explanation.  When two
unlike surfaces, in their usual state, are pressed on each'
other, the fact of the pressure shews that their surfaces
are brought within the distance at which the ether charge
of each surface can exercise a strong repulsion. But this
implies also a sensible action of each surface on the ether




CHAPTER IX.                    143
charge of the other.  These three new forces, when the
two surfaces are chemically or mechanically different, must
cause an altered distribution of the two charges of ether
between them.  One will gain, and the other lose.  And
this change must extend to the surfaces themselves. Those
which receive an excess of ether will have their distance
from  the lower stratum  increased, and probably assume
also a more polar, in contrast to an equatoreal arrangement, while the other surface will undei'go in both respects
an opposite change.  Such surfaces, if capable of retaining
this new state, when removed laterally, will have a posi"
tive and a negative electricity.
1.00.  "Polish  increases the tendency qf a body to
acquire vitreous, and elevation of ternperature its tendency
to acquire resinous electricity."  (De la Rive, I. p: 13.)
These results flow at once from  the theory.  Increased
temperature, since it implies a greater oscillation or rotation of the atoms, must diminish their retentive power
over the ether, and disengage some portion of it.  Again,
a polished surface must be more nearly a true plane than
one unpolished. The action will become that of the whole
surface, instead of some prominences only, and the tendency must be, that the polished surface will attach a larger
share of the double charge.
A similar result follows, when two bodies of the same
kind are rubbed together, a large part of one over a
smaller part of the other. The larger surface is plainly
that which is drawn away from  the other. The pressure,
before the motion, will drive out part of the common
charge to the edges of contact, where it will be retained
by the double attraction.  The moved surface, when withdrawn, will attract part of this excess, which will be




144            ON MATTER AND ETHER.
replaced from the parts in contact, and through these, fiom
both the touching surfaces. Thus the moved surface will
obtain an excess of ether, and be positive, and the unmoved
one be negative.
101.  To ex2l1ain Electrical Conductivity.
This property forms one main electrical contrast between different substances, and links the science directly
with the chemical properties and structure of bodies.
So long as a charge resides on the surface of a body, it
must imply a change in the outer strata of the body itself,
and chiefly on the outmost. This may be of two kinds;
its elevation by a kind of capillary action to more than its
mean distance from the strata below, and a varied arrangement of the poles, in the case of rotation, so as to become
more or less receptive of ether than before. In a body
positively charged it seems clear that the poles will be
more turned to the surface, and in one charged negatively,
the equators, as a more repellent position. Now if we suppose that, in non-conductors this change of the poles is
more decided, and not capable of lateral transfer without
great difficulty, and that in conductors there is either
expansion without change of poles, or an easy transfer
of the polarity, the contrast in their electrical properties
is at once explained. In one case the charge may be
compared to a land-flood over a level surface, and in the
other to a series of lakes, embosomed in hills.
The metals are all good conductors, though the degree varies.  The diamond, mica, glass, sulphur, jet,
amber, resin, and gum lac, are non-conductors. All the
last, except the diamond and sulphur, have a small or
moderate density, andl chemical atoms of a rather high
degree of complexity. Hence it is clear that the bulk of




CHAPTER IX.                   145
the space which belongs to each chemical atom, and which
may be occupied by ether, is relatively great.  Again, the
diamond, it has been shewn to be probable, has a purely
octahedral structure, which implies a cup-like form  for
all the spaces between the atoms which form its surface.
The metals have precisely an opposite  structure, and
probably, in most cases, have terminal planes, forming a
level kind of surface.
102.  To account for Electrical Attraction and Bepulswon.
The fundamental law is thus expressed.  " Sufaces
charged with like electricities repel, and with unlike attract
each other, and the force of attraction or repulsion varies
directly as the product of the two intensities, and inversely
as the square of the distance."
The diminution of force as the inverse square is here
no proof of a direct law of central force of that particular
kind.  For the intensity of light varies by the same rule,
which results, in that case, from the properties of space,
when motion is propagated from a given centre.  The
law  in this instance is secondary and derivative, not
primary and fundamental, and the same explanation may
apply to the attraction and repulsion of electrized bodies.
The same view seems to result also from direct experiments.  For Sir WV. S. Harris has shewn that " the
attraction of electrized bodies depends wholly on the form
of their opposed sides, and not on that of the rest of the
body. Two cones opposed by their base attract just as
much as two circular discs, equal to their bases, and
two hemispheres as two spheres of the same diameter
(De la Rive, I. p. 68), and the attraction between two circular
discs, one larger than the other, is the same as between
10




1.46            ON MATTER AND ETHER.
two surifaces equal to the smaller."  These results seem
wholly adverse to the theory of two electric fluids with
central forces of attraction and repulsion, emanating in all
directions. In this case the charge on the averted sides
would have a full share in the total action;
Let us now consider the natural results, on the present
hypothesis, of the modification of the surfaces of bodies
just described.
Since the repulsion of the ether diminishes by a high
inverse power, as the twelfth, it must be insensible at very
small distances.  The increase or diminution of the ether
on the surface'can thus produce no sensible attraction or
repulsion, depending immediately on the special law of
repulsive force.  But since the elasticity of the medium is
very great, and its pressure amounts to eighteen billions of
pounds per square inch, it is eminently suited to transmit
impulses, or vis viva, from one surface to another, whenever it is disturbed from absolute rest.
The ether of the atmosphere, however, can never be in
a state of simple rest.  For besides the annual and diurnal
motions of the earth, which must tend to disturb it, the air
has evidently its particles at a distance from each other
at least eight or ten times their own size, and constantly
changing their position by a rapid motion, which causes
their repulsion or elasticity.  Hence disturbances must
be constantly propagated through the ether in all directions, even if due to this cause alone.
Besides the statical,pressure, which the,free ether
exerts on all the bodies it surrounds, there will ithus be
a dynamical pressure, arising from the motion constantly
diffused through it.  The force thus caused by any local
compression will plainly diffuse itself by the same law as




CHAPTER IX.                   147
the waves of light or sound, or its action on a distant part
will be inversely as the square of the distance in the same
lihe, while the nature of the disturbance will enter into the
law of lateral or angular diffusion..
Let us now suppose that the effect of an increased
ether charge, with its change of the poles of the matter,
is to increase the elasticity, or the completeness and directness of the rebound, when free ether impinges on the
surface. The body will then exercise an increased repulsion on all sides. But since there: was equilibrium
before, it will still continue, the change being equal in all
directions.
Now let a second body, freely suspended, like the first,
undergo a similar change. Let the repulsive force of the
first be 1 + e, and of the second 1 +f, compared with the
mean value. Impulses which fall on the first are returned
in the proportion of 1 + e, and those on the second in the
proportion 1 +f.  Hence the secondary impulses which
have been reflected from both surfaces, will have the ratio
1 + e +f+ ef to their nominal value.  Of these terms, the
first is the normal repulsion itself; and the second and third
balance the two extra repulsions on the outer sides of the
two bodies. But ef is a term of the second order, which
remains without compensation, and measures the relative
repulsion of the two bodies. It is positive when e and f
have the same sign, and negative when they are different.
It follows that there will be a positive repulsion between
two similarly charged surfaces, and a negative repulsion or attraction between unlike surfaces thus opposed.
The force also will diminish  as the inverse  square
of the distance, but only for the surfaces which directly
face each other, and in other cases will diminish rapidly,
10-2




148             ON IMATTEt AND ETHER.
not only with the distance, but with the mutual inclination.
103. The general law of force, resulting from this
view, will agree with that derived from the fluid theory in
depending on the two intensities and the inverse square of
the distance, and in being repulsive for like, and attractive
for unlike charges.  But it differs in two important respects.  The force will diminish rapidly with the inclination of the surfaces, as well as their distance, and it will be
destroyed, or wholly modified by the interposition of solid
matter.  This corresponds perfectly with the general conclusions deduced by Sir W. S. Harris from his experiments.
Again, it has been seen that when spheres of radii 2, 4, 8,
are separated after touching a sphere of radius 1, the
changes are found to be 1'0S, 1'30, 1'65, while by the fluid
theory they are t116, 1.31, 1'444. Now it is plain that the
present theory, which makes the force diminish, not only
with the square of the distance, but the inclination, will
tend to increase the relative influence of the larger sphere;
and thus its values will differ from those deduced by
the fluid theory in the same direction as the experimental
values.
"Sir W. S. Harris has shewn that, when the charge is
feeble, the increase of force is not exactly. as the square
of the quantity, but varies more rapidly.  Thus in one
experiment, when the quantities were doubled, the repulsions were as 1 to 5." (De la Rive, p. 67.) This result is easily
explained on the present view.  The increase of ethereal
elasticity is not the same thing as the quantity of surcharged ether.  If we assume that, in weak charges, a
portion is latent, and does not act sensibly at the surface,




CHAPTER IX.                    149
the effect here noticed would ensue.  If one fifth of the
smaller charge were latent in each case, the active ratios
would be 42: 92, or just one to five, as in the experiment.
104.  The question still remains, in what way a surcharge of ether can act in varying the modulus of elasticity for the surface, or increasing or diminishing its repulsive
energy towards the free ether which impinges upon it.  It
results from the laws of mechanics, and the assumed constitution of the atoms, that no vis viva can be destroyed,
but can only change its form.  But it seems plain that if
the external ether impinges upon revolving equators, instead of fixed poles, it will partly modify their rotation,
and partly be repelled tangentially, or along the surface.
If this explanation be correct, the continuance of negative
electricity on the surface of a body is connected with the
production of an answering amount of atomic heat in the
body negatively electrized.  It agrees well with this conclusion, that collodion and gun-cotton are the extremes in
the list of negative electrics.  For these are both explosive
substances, the latter in the highest degree, and their
atoms must therefore be naturally receptive of insensible
atomic heat in the same proportion.
105.  To explaihn Electric Incdcction.
" When an electrized. body is presented to an insulated
conducting body, signs of electricity are developed, even
though the bodies are a greater or less distance apart.
These signs disappear as soon as the electrized body is
withdrawn. This constitutes electricity by induction." (De
la Rive, p. 82.)
This phenomenon results directly from the nature of
electrical action here supposed. For the excess or defect




150            ON MATTER AND ETHER.
of dynamical pressure on the side opposed to the electrizedc
surface must alter the arrangement of the ether or electrical charge.  It will dispose itself in such a way that the
lateral pressure from the difference of the ether charge at
different parts of the surface. compensates the difference of
external or dynamical pressure, arising from the pressure
of the electrized body.
106.  General Lazw of )istribution on Conducting Surfaces.
In the fluid theory, as developed by Coulomb, Poisson,
and Murphy, &c. the self-repulsive force of either fluid is
supposed to drive it to the surface, where it is detained by
the pressure of the atmosphere.  The law of its distribution depends then on the shape of the surfaces, being
uniform in a sphere, but unequal in every other figure.
Some simple cases have been calculated by the theory,
with the help of a rather high analysis, and the results
agree moderately well with the experiments of Coulomb.
The general conclusion is that the accumulation is greater
where the curvature increases, as at the end of the minor
axis of an ellipse, and is infinitely great at points or
angles.
On the other hand, Sir W. S. Harris concludes from
his experiments (Brit. Ass. Rep. 1847, p. 24) as follows:
" First, that the influx of a charge is uniform, like the
filling of a vessel with inelastic fluid, like water, and
not with elastic fluid, like air. Secondly, that the distribution is equal, apart from induction, so that the intensity
of a charged rectangle is the same as when rolled into a
cylinder, and of a circular area, the same as in a sphere of
the same surface.  He infers that if a single charged body
were to exist alone, there is no reason to suppose an




CHAPTER IX.                   1~51
unequal distribution.  Thirdly, that the whole action of
two opposed spherical surfaces depends on the distance
of each pair of corresponding points, and may thus be
reduced to a very simple formula, depending on th, eir radii
and mutual distance.
The contrast between these conclusions, and some of
the results of other experimenters, seems to prove the need
of further inquiry, before the facts can be viewed as thoroughly ascertained.  Estimates of electrical force require
peculiar accuracy and care for their determination. But
the conclusions of Sir W. S. Harris agree in substance
with the consequences of the present. theory.
First, it seems incredible that each point of two electrized
surfaces acts only on one point of the other, singling it out
by a kind of elective affinity.. On the other hand, a calculation based on this principle will approach to the case
where the action diminishes with the inclination as well as
the distance, more nearly than the complex calculation
from fluids of equal force in all directions. It will not
be difficult to solve the simplest cases, with an assumed
law  of decrement for the inclination, and  to  shew
that they approach nearly to Sir W. S. Harris's empirical
rule.
Again, the present theory agrees with the conclusions
of Sir W. Harris, in viewing the influx of a charge as
resembling more nearly the influx of water than of air.
On the theory of two fluids, the whole internal space of
the body is equally receptive of the fluid, and it is driven
to the surface by its self-repulsion alone.  On this view,
also, the higher intensity at the minor axes of an ellipsoid is due to the repulsion of the whole charge, acting in
straight lines through the substance of the body.  The




152             ON MATTER AND ETHER.
present theory, on the contrary, supposes that the change
resides on the surface, because it is only at the surface
that the relations of the matter andi ether are discontinuous, and the distribution resembles the case of a soluble
gas, admitted into a space of very small height over a
large liquid surface.  The self-repulsion of the charge will
be insensible for all sensible distances; and hence its distribution, apart from  secondary action or pressure, will be
sensibly uniform, so far as it depends on central forces
alone.  But the equilibrium  required between the lateral
pressures and the retaining force will cause it to be denser
where the curvature is greater, and most of all at edges
and angles, though in a less ratio than in the fluid theory.
107.  Particular Cases of Electric Distribution.
The statements of De la Rive and Sir W. Harris, compared, answer to the conclusions that appear to flow naturally from the present hypothesis, though a full comparison
would require complex calculations, and a reference to the
conducting or coercing power of different substances.
(1) " In the Ellipsoid the charge at the ends," according to IDe la Rive, "is proportional to the axes."
(2)  " Those plates, whose length is at least double the
breadth, have the charge nearly constant, till about an
inch from  the'end.  It is double at the end, and if the
proof plane is put in the prolongation of the plate, fourfold."  The retentive force on the ether, at the edge, has
to counteract tw8 equal pressures from thie two sides in the
same direction, and must therefore, it would seem, be
double the force along the side of the plate. At the corners, for a like reason, it would be fourfold, and the proof
plane held in the prolongation of the plate, is under the
same condition, and will naturally receive a fourfold




CHAPTER IX.                  153
charge, that is, an amount of ether causing a fourfold
resistance or tension.
(3)  "In a circular plate, it increases slightly to an
inch from the edge, at one third of an inch is double, and at
the edge is triple."  The resolved part of the pressure of
the edge which meets and balances the pressure on each
side is 2 sin 00, and the total pressure f  80. Hence it
would seem that the charge at the sharp edge will be wr or
3- when the charge along the surface is unity; while its
diminution inward will probably vary with the size of the
plate, and the conducting or coercing power.
(4) "In a cylinder 33a inches long, and 2 in diameter,
the charge being unity in the middle, it is 11 at 1'8 from
the end, and 2To at the end."  The charge at the circumference of the end, where there is a right angle, it seems a
probable conclusion, from the theory, and the balance of
pressures  should be:  compared with that along the
cylinder. But the end being small compared with the
whole surface, this charge may be diffused over the whole
end, and thus require the same ratio at the circumference
to balance its own increased pressure. The extreme value'would then be 4- = 2'46, as its limiting value when thle
radius of the end is small, compared with the length. At
a distance from the end equal to the radius, it would probably be -= 1'57, and hence a value 1'25 at the distance
of 1'8 seems to agree with this approximate result of the
theory.
(5)  "In twenty-four equal spheres in contact, it is




154            ON MATTER AND ETHER.
nearly constant for the middle ones, and 1'75 for the extremes."  Such a series evidently approaches to the case
of a long cylinder with hemispherical ends. In this case,
we should expect a double strength of the charge at the
ends, to meet the opposite pressures, reducing itself to
unity a little beyond the first hemisphere. Hence the
mean charge of the spheres next to the ends may be expected to be 1'5, or nearly a mean between the limiting
and central values; and the mean charge of the last spheres
a mean between this and the limit, or 1'75.
Thus a first and rough application of the present theory
to the best ascertained facts of electrical distribution yields
results equally, and perhaps more conformable to experiment, than the fluid theory. At the same time, since it
recognizes the double influence of induction and the conductivity or coercive power of the substance electrized,
and requires us to distinguish the quantity of ether distributed along the surface from the elasticity or electric
force which it occasions, it plainly admits of two elements
being introduced into the formula of electric distribution,
by which the harmony between theory and experiment
may be rendered more complete than in the fluid theory,
which takes no account of the varieties of coercing power,
and makes the charge a direct measure of the external
activity.




CHAPTER X.
ON THE ELECTRIC CURRENT.
108. THE Science of Dynamic Electricity, while it
has made immense progress through the labours of Volta,
Wollaston, Davy, Oersted, Ampkre, Cumming, Becquerel,
Faraday, De la Rive, and many others, still remains in a state
not a little perplexing and obscure. Electricity, chemical
affinity, magnetism, light and heat, are all proved to be
intimately related to each other, and the relation of each
pair of them supplies a large class of phenomena, but the
exact nature of each and all continues unknown.
Electro-dynamics, or the theory of the electric current,
and of the attendant chemical union and decomposition,
stands first in order among these closely related branches of
science. And here the unsolved questions are many. What
is the meaning of an electric current?  Is it the transfer
of one or two fluids, properly electric, or of the luminous
ether, or a transfer of forces alone? Why does it decompose chemical compounds, and some, not others? Why
should such currents circulate, as the hypothesis of Ampere assumes, around the atoms of magnetic bodies? Why
should electricity, in motion, have a power to attract or
repel, which ceases when it is in repose? Why should




156            ON MATTER AND ETHER.
one current cause another for a single moment, when
formed or broken?  Why should two solid and one liquid
conductor be usually required?  Why should heat alone
produce such currents?  Why should the same elements,
joined in pairs, have constantly the same electric character,
as relatively positive or negative?  Why should gaseous
elements occupy one end of the series, and earths and
alkalies the other?  These and many similar questions
seem to baffle, while they stimulate, the curiosity of scientific men.
109. Two rival views struggled long for victory in
the general conception of the voltaic circuit, the theory of
contact, and the chemical theory.  The latter has now
prevailed, through the labours of Faraday and De la Rive;
but the part fulfilled, either by the liquid, or by the union
of the two metals in the circuit, remains very obscure.
Dr Turner states the view of Davy as follows, and suggests
a modification.
"Sir H. Davy considered chemical substances to be
endowed with natural electric energies; meaning thereby that
a certain electric condition, positive or negative, is natural
to their combining molecules; that chemical union is the
result of electrical attraction taking place between oppositely
excited atoms; and decomposition from combined atoms
being drawn asunder by electric energies of other atoms,
more potent than those by which they were united. He
regarded the poles of a voltaic circuit as two centres of
electrical power, acting by repulsion on particles of the
same electric state as itself, and by attraction on the opposite.  Substances which appeared at the + pole were
termed electro-negative, and those electro-positive which
were separated at the - pole....If he meant that a particle




CHAPTER X.                    157
of free oxygen or chlorine is in a negatively excited state,
this is contrary to the fact. If sulphur unites with oxygen
because it has a positive energy, why should it nnite with
potassium, which is far more positive than itself?  The
only way in which these facts seem reconcilable with the
theory, is to suppose all bodies in their uncombined state
electrically indifferent, but that they have an appetency to
assume one state in preference to another. Electro-negative bodies are such as assume negative excitement under
a certain approach to others, which at the same time become positive, chemical union being the consequence. On
this view it is intelligible that sulphur may be positive to
oxygen and negative to potassium.  The following view
seems best to harmonize the facts and the laws of electricity. A particle of zinc and one of oxygen, possessed
of positive and negative electricity, assume, in combining,
opposite electric conditions, and combine in consequence;
adhering together by virtue of their opposite states, as two
oppositely excited balls are mutually attractive. The zinc
particle, on becoming positive, gives off negative electricity to the mass of zinc to which it belonged, and the
particle of oxygen, on becoming negative, supplies positive
electricity to adjacent particles. Thus electro-positives, in
combining, give out negative, and electro-negatives positive
electricity." (Turn. Chem. ed. 7, p. 128.)
Again, De la Rive states the views of Ampere and Berzelius, and his own latest conclusions.
"When we study these phenomena, we are forced to
admit a simple relation between the atom and electricity.
Ampere had supposed that each atom of matter possesses
an electricity proper to itself, positive or negative, and
that in the state of equilibrium it is surrounded by the




158            ON MATTER AND ETHER.
contrary electricity, which disguises the former.  This
hypothesis, which explains elegantly a certain number of
facts, is open to grave objections. It does not explain
how the same atom can be sometimes positive, at other
times negative, according to the atom with which it is in
relation. Berzelius admitted that each atom has two electric poles, one positive and one negative. But to this
simple hypothesis another was added, not at all probable,
that atoms are unipolar, or keep one of their electricities
in combining, and abandon the other...I. am disposed to
admit in the atom a natural polarity. All the facts relating
to the development of electricity, particularly by heat,
seem to lead to this conclusion. With respect to the objection, that the atom being naturally spherical, there is no
obvious reason why it should have polarity in one direction
rather than another, we have only to suppose that each
atom originally received a motion of rotation upon itself,
and we obtain an axis and direction of rotation, and a different pole at each extremity." (Vol. II. p. 48.)
This view is'unfolded more fully in a later passage.
"The principle from which we set out is, that every
atom has two electric poles, contrary and of the same force.
Whether this is due to a movement of rotation on itself,
or to another cause, is of little importance; it is with us a
primitive fact. One atom differs from another, only inasmuch as it has a more powerful polarity than the other,
but in the same atom the two poles are of the same force.
When two atoms are brought near, they attract by their
opposite poles; but as they are spherical, they can come in
contact only by one of the poles of the former, and the
contrary pole of the latter. We shall be obliged to admit
a principle which, it seems to us, is founded upon a great




CHAPTER X.                    159
number of facts; that when two atoms are free and insulated, the positive pole of that which has the stronger
polarity unites with the negative pole of that which has
the more feeble polarity. If they have the same force of
polarity, there is no reason why they should unite by two
contrary poles, rather than the other two. Then they are
not attracted by their poles, but simply obey the molecular
attraction; and this is the case of homogeneous atoms, or
of cohesion; whilst, when the atoms are heterogeneous,
they are attracted by their opposite poles, and then obey
chemical affinity.  This is therefore the res-Lilt of the
attraction of two differing atoms by their contrary poles;
so that the positive pole of the more powerfully polar is
united with the negative pole of the other. The compound atom has equally two poles; and these are equal,
because the excess of the more powerful over the more
feeble of those united neutralizes part of the electricity of
the free pole of the -more powerful: the compound atom is
therefore found under the same conditions as the free atom.
Thus chlorine will unite by its positive pole with hydrogen, and by its negative with oxygen. But if we place the
compound atom between contrary polarities, it will be so
arranged that its + pole is turned to'the negative, and its
- pole on the positive side, of the same pole... The difference between the natural state of a liquid, and its electric
polarization is this, that in "the former state the molecules
are in complete electric equilibrium, and the equal and
contrary electricities with which the two poles are endowed, unite by the surface; while in the latter state the
equilibrium is broken, the contrary electricities no longer
uniting by the surface, but the positive poles are all turned
on the negative side of the pole, and the negative poles on
the positive side." (Vol. II. pp. 875-7.)




160            ON MATTER AND ETHER.
110. None of the views of these five eminent men
is probably without a partial truth.  But their divergence shews the difficulty of the subject, and the cloud
which still rests upon it. They all share the common
objection, that they make electricity consist of two distinct, non-convertible fluids, one positive, and the other
negative, strangely combined, and as unaccountably separated, when so many facts imply that the two states are
simply correlative, since the same substance may be positive to one and negative to another substance. But each
of them is liable to further difficulties.
First, the view of Davy lies open to Dr Turner's objection, that free, uncombined elements shew  no trace of
either electricity, and are sensibly neutral. And next, the
analogy fails in the main point.  For when opposite
electrics attract each other, the attraction ceases with the
discharge; while in chemical union there is no apparent discharge, but abiding attraction. Again, the two
fluid theory, in dealing with static electricity, assumes
their distribution to be independent of their action on matter. But the view of Davy requires us to assume the
reverse, that their attraction for matter is more powerful
than for each other, and that this superior attraction finds,
in every element, a distinct and graduated amount of one
fluid only.
The remedy Dr Turner suggests for one of these faults
introduces another still more serious. For what reason
can be given why two neutral elements should each part
with one of the neutralized fluids on the mere presence of
the other? Why should a separation, reversing the assumed laws of electric attraction, take place in both at the
same moment? How can we account for the one attractive




CHAPTER X.                    161
force of the two elements, by assuming a separation in
each of them, with no force at all, of two electricities mutually attractive, and previously united?   The difficulty
thus introduced seems twice as great as that which it attempts to remove.
The view of Ampere agrees with that of Sir H. Davy
in ascribing to each element a proper or constituent electricity; and both are in this respect, perhaps, nearer the
truth than Dr Turner's modified explanation.  But when,
on the principles of the two-fluid theory, he supposes the
opposite electricity to be present in equal amount, and to
disguise the first, he falls back into the original difficulty.
The true conception of a proper electricity is that it is selfdisguised or latent by the structure of the atom.  But
if it requires to be heutralized by an equal amount of the
other kind, we return to the point from which we start.
We have merely the standard case, in the fluid theory, of
matter with two neutral electricities, with an unexplained
propensity, in each pair of elements, to part with opposite
fluids in presence of each other; so as to create, by this
double sacrifice, effected without any force, a mutual attraction, which is assumed to last, against all analogy,
when their combination has mlade them  neutral once
more.
111. The later and riper hypothesis of Prof. De la IRive
introduces a new and important element, when it suggests
that the atoms are essentially polar, and probably through
a movement of rotation. This idea is a great step towards
a full solution of the problem.  But the suggestion is half
retracted in the second passage, where the polarity is
called an ultimate fact, of which the precise cause is not
important; and the further assumption, that the atoms are
1'1




162            ON MATTER AND ETHER.
spherical, robs the first of its chief value, while the explanation is defective and imperfect in other ways.
First, the polarity of rotation is of a definite kind. It
implies two poles, equal and opposite, on the two opposite
faces; but these equal polarities are plainly inseparable,
and can never neutralize each other. Two atoms, polar in
this sense, could have no excess of positive or negative
polarity, but must be positive on one side, and equally
negative on the other, and the one which is the more
positive must also be the more negative. Hence a gradation of positive and negative electric character, if positive
and negative are defined by right-hand and left-hand rotation, would plainly be impossible.
Next, the different degrees of polarity, in the hypothesis
of revolving spherical atoms, could consist only in different
rates of revolution. Now there may be plain mechanical
reasons why two revolving atoms, either of equal or unequal velocity, should unite with unlike poles together, so
that the direction of motion may concur. But there is no
conceivable cause why one pair of unlike poles should
combine, rather than the other, the relations of each pair,
both of common direction, and equal or unequal velocity,
being just the same. Positive and negative, when applied
to the opposite sides of such atoms, are convertible terms;
and there is no such difference as could explain the supposed law, that the north pole, for instance, of the faster
should combine with the south pole of the slower atom, and
the south pole of the faster never combine with the north
pole of the slower.
Thirdly, the supposition that the excess of negative
electricity of the stronger atom  would  be neutralized
by the surplus of the inner or united pole, seems to be




CHAPTER X.                   163
an illusion from the ambiguity of terms. If neutrality
consists in the equality of contrasted motions on the
opposite sides of the atom, then the rotation must be equalized before it can be true of the compound atom. But if
the opposite electricities are conceived to be separate and
in polar contrast, in the simple atoms, then the difference
of rotation in the two inner poles will have no effect to
neutralize the excess of the negative pole in the compound
atom.  Two different senses of the term  positive, as
applied to like poles of rotation, or to a greater or less
amount of rotation, seem to be confounded together.
Fourthly, the assumed law of union, besides its strangeness in itself, since it seems to imply a choice without a
determining reason, appears inconsistent with the presumed course of electrolytic action. Calling the north
pole positive, or that on the side of which the motion
is the reverse of the hands of a watch, it is assumed
that the north pole of the oxygen joins the south pole
of the hydrogen in each atom; or if the line be north
and south, and the revolution the same way as that of the
earth, then each atom of oxygen will be south of that of
hydrogen, and the free north pole belongs to the hydrogen
and the free south pole to the oxygen. When the terminal particles are withdrawn, and the nearest unite, it
is plain that the order will be reversed, and the south pole
of the oxygen in the first atom combine with the north
pole of the hydrogen in the second. No subsequent reversal of position, for the electrolysis to be renewed, can
alter the fact of this change. In fact, the view of electrolytic action, adopted from Grotthus and Roget, clearly
implies the perfect indifference of the pairs of differing
atoms, on which side they are united together. For these
11 —2




164             ON MATTER AND ETHER.
reasons, besides others to which Professor De la Rive himself
alludes, the explanation lie has offered, though perhaps
a nearer approach to the truth than those of his predecessors, appears to labour still under a serious and insuperable defect.
Let us now return, to consider what light may be
thrown on this very difficult subject by the present view of
the atomic structure.
112.  To explain the diverse Polarities of the Chemical
Atoms.
Every chemical element, on the present view, is not
a solid sphere, either in motion or at rest; but consists of
a definite number of units, duads, centres of force, or
monads of matter and ether inseparably joined together,
arranged in some definite order, revolving usually round
some axis of rotation, and parted from the nearest elements by a certain amount of attached ether.  Their free
ether, again, is supposed to consist of a finite number of
monads, not very disproportioned either in their distances
or number to those of the material units, or resembling
less a fluid atmosphere than a large number of satellites.  Again, the pressure of the free ether will be
transmitted throughout all bodies by the perfect elasticity
of the monads and units, and will condense and compress
every. chemical atom, so as to isolate them  from  each
other.  Their cohesive affinity, it will result from the facts
of science, and the assumed laws, will be considerably less
than this ethereal pressure; but it will operate equally in
spite of this disproportion, just as the atmospheric pressure,
being equal within and without, leaves the texture of all
animal tissues unimpaired.
Every such element, then, must include in its very




CHAPTER X.                     1 16
5trncture four or five different sources of contrast, from
yvhich a kind of polarity may arise.  First, there is the:ontrast between the duads or units of matter, which
ittract only beyond the first or neutral distance, and the
nonads of attached ether, which are repulsive to ether
it all distances.  Secondly, there is the contrast between
X larger or smaller charge of ether to the same element,,yiving rise to a polarity of quantity and not of reverse
position, and hence admitting of graduation. Thirdly,
there is the possible repulsion of the ether to one end
or side of the atom, so as to clothe it unequally, another
contrast which admits degrees of intensity. Fourthly, there
is the contrast of a swifter or slower rotation, admitting
also of various degrees.  Fifthly, there is the contrast
of radial or axial structure, admitting of a few distinct
gradations alone, from  the most centrical to the most
open or cyclical form.  Sixthly, there is the contrast
between north and south poles of rotation, or oppositely
placed hemispheres, and this is one of complete equality,
but incapable of degrees, or of neutralization.  Seventhly,
there is the contrast between the plane of the equator
and the line'of the poles, or two rectangular axes, along
which there is a special repulsion, and a third, along which
there will be a special attraction of double the amount.
All these contrasts may be included ucnder the general
term  of polarity.  They are also linked together, in the
hypothesis, by mechanical laws. But they clearly differ
very much from one another, and their combination will
account for the natural perplexity which has arisen from
the constant appearance of polarity in all the phenomena,
and the complex and almost inconsistent features this
polarity assumes.




166            ON MATTER AND ETHER.
113. The first kind of polarity or contrast, which lies
at the basis of the science, is the distinction of vitreous
and resinous, or positive and negative electricity.  In the
theory of Franklin, this depends on the excess or defect of
one single electric fluid; but in that of Symmer, Du Fay,
Coulomb and Poisson, which has been more prevalent,
on the pressure of two opposite fluids, exactly equal in
quantity and similar in properties, but self-repulsive, and
mutually attractive, and differing in sign only. This view
makes it impossible to give any explanation how one fluid
can be separated from the other, or any difference in their
affinity for any atom exist between them.
On the other hand, there are many facts which agree
with the hypothesis that excess and defect in the quantity
of the same fluid or cause of force is the true contrast
of positive and negative excitation. Thus heat increases
the tendency of a body to become negative, and increase
of motion would plainly throw off part of the attached
ether by common mechanical laws. " The greater expansive force of positive, compared with negative, electricity
for equal tensions is established by a great number of
phenomena" (De la Rive, ii. p. 883). Again, the neutral
state, on this view, would not be absolute and invariable, from the very nature of two fluids, but will depend
on the special class of relations considered, whether the
exchange of ethereal pressure between solid surfaces, the
friction or contact of different surfaces pressed together, or
still closer atomic approach in chemical combination.
Accordingly, we find that elements which are neutral in
reference to distant and general action, are strongly
positive and negative in their atomic approach, as oxygen
and potassium. The fact, also, that their electric relations,




CHAPTER X.                    167
as positive or negative, throw the chemical elements into
a series, with gaseous elements at one end, and the bases
of the fixed alkalies and earths at the other, proves that
the contrast is not like that of two faces of rotation, or two
opposite parts of an indefinite straight line; but resembles
rather the difference of higher and lower temperature, and
approaches to a real zero, or absence of ethereal activity
or expansive force at one end of the scale. If we assume
positive electricity to consist in an excess, and negative in
a defect of the mean amount of attached ether, the main
features of contrast will be the same as on the other view;
but the possible change of this mean under different relations will account for many phenomena otherwise inexplicable, and elements at the extremes of the scale will
evidently have, as experience confirms, a wholly different
constitution.
114.' The phenomena of the Electric Discharge agree
with this view  of the two electricities.  Its velocity in
copper wire, by Wheatstone's  experiments, is 288,000
miles per second, or one half greater than that of light
in space. But the tension of the ether, in solid substances,
must be increased for direct and rapid impact, and the
velocity, like that of sound in water, be greater than for
transverse undulations in the planetary spaces. Yet the
relation is so near to equality, as almnost to prove that there
is a direct ethereal impact; as when a series of equal ivory
balls, in a right line, are struck by a first ball, the last
will detach itself with a nearly equal force at the other
end.
115. A second kind of polarity or contrast is that
which appears in the directive power of an electric current.
When it passes horizontally from north to south, a needle




168            ON MATTER AND ETHER,.
below it has its north pole turned to the east and a needle
above it to the west.  But when the positive end of the
current is to the south, and the negative to the north, these
directions are reversed, and so in any other position.  We
have here a strict polarity, without graduation, which is
satisfied at once, by supposing the directive power to depend on the direction of the movement, and the atomic
rotation.  The plus and minus, in this case, are independent of the force of the current or the limit of neutral
electricity.  They depend simply on the two opposite
directions of the current, supposed to be of a single fluid or
ether, and in one direction alone, not in both directions at
once, as in the double fluid theory.
116. A third contrast is that of native electricity, or
the electro-motive order of the elements.  There is here
a regular scale, from oxygen at one end to potassium  at
the other, though liable to deviations and partial inversions according to the nature of the fluid in the circuit.
Still, there is a plain distinction in the character and
properties of the beginning, middle, and end of the scale.
Here we have the signs of a polarity or contrast, intermediate to the two others.  It is not a simple antithesis, for the same body may be positive to one element,
and negative to another.  It admits therefore of a certain
amount of graduation.  On the other hand, it does not
seem capable of indefinite extension, like a positive and
negative quantity, but has a fixed limit, apparently, at
each end, beyond which no element more positive or more
negative can be found.
These features, which seem  inexplicable in the case
of spherical atoms, find a simple explanation on the present
view. They correspond to the varieties of axial and radial




CHAPTER X.                    169
structure, in compound atoms composed of a definite number of units and monads.  These are not a simple contrast,
like the two poles of rotation, but admit of several degrees.
At the same time they have a limit, each way, in the most
cyclical or most axial structure consistent with permanence, and the actual conditions of molecular structure.
Thus oxygen, nitrogen, fluorine, at one end of the scale,
are gaseous elements which cannot be condensed; chlorine
condenses with difficulty, and sulphur, iodine, bromine,
phosphorus, and selenium, are volatilized with ease; while
the earths and alkalies are basic, and almost unsusceptible
of being turned into vapour. An axial structure, which
implies a low rate of rotation, or comparative rest, is most
favourable to the attachment of ether, and a rapid motion,
causing repulsion, is most unfavourable; so that the normal
state of the bases may be called positive, and that of
the opposite elements, negative, by their very structure;
while they are externally neutral, or in a mean state, until
their relations are changed by contact and union with
each other.  Thus the fundamental idea of Davy and.Ampbre will be retained, that some substances are naturally
negative, and others positive, but will be cleared from an
addition, borrowed from  the fluid theory, which obscures
and destroys its true meaning.  This natural electricity
does not need to be neutralized by a second fluid, but
is the direct result of the atomic structure, and leaves
the substance neutral, whenever its atomic structure is not
altered by union or separation. Again, the objection which
Dr Turner has brought against Davy's view is removed.
For a swiftly revolving atom must be in eq~uiibrio, with
regard to external pressure in general, like one at comparative rest, or of axial form; and still its absorptive or




170            ON MATTER AND ETHER.
negative character will be apparent, as soon as its rotation
is diminished by union or even contact with other atoms.
117. A  fourth contrast, not abrupt but gradual, is
that between conductors and non-conductors or dielectrics,
on which so many phenomena depend. Liquid conductors
seem to have a middle character, and to be capable of
conducting by electrolysis alone. On the present view,
it depends on the ease or difficulty with which attached
ether can transfer itself from one atom to another, surmounting the resistance of that transmitted ethereal pressure, by which they are parted from each other. Now it is
plain that, in metals, from their higher density, a larger
space will be occupied by the nuclei, and less by the
attached ether, and a stronger cohesive force traverses the
interval, so that on both accounts the transfer of ether
is more easy. Again, it seems plain that the ease will be
greater where there is an approach to a cubic or spherical
form than where the length or breadth is unequal. Accordingly, silver, copper, gold, the best conductors, are
found very near the middle in the electric series of elements.
Again, the polarization of dielectrics will answer to the
condition of the atoms, when there is a strong retentive or
coercing power in the attached ether, but it is disposed unequally on opposite sides of the element, from the charged
state of neighbouring atoms. The contrast, again, between
a swifter and slower rotation, in connection with the varied
structure of the atoms, will link itself with the properties
of conductibility for heat, thermo-electricity, and the development of heat in chemical combination.
118.  lb define the nature of the Voltaic Current.
The main conditions on which the Voltaic Current




CHAPTER X.                    171
depends are the contact of two different metals, and their
union by a fluid conductor, acting chemically upon the
more oxydable metal. When there are many cells, and
the extreme plates are joined by metal wires, the current
is closed and active, or broken, as the wires touch, or meet
in a liquid conductor, or else are withdrawn from  each
other.  There is thus, included by the air and non-conducting cells, a circuit within which positive electricity
travels one way and negative electricity the other; and the
strength of affinity, by which the zi-e is oxydated in the
cells, measures the strength of the electrolyteic power be —
tween the ternminal wires, when placed in water or some
other fluid. The intensity of the electricity, also, increases
with the number of cells; but the heating effect is greater
with single plates of large surface, and the deflecting power
on the needle depends on the quantity, and not the intensity
of the current. Its velocity varies with the nature of the
wire and lateral induction; but the results of experiment
place it, when highest, at three fifths of the velocity of
light, and it seems to be retarded by induction to one
fiftieth only of that velocity. The contest between the
contact and chemical theories seems now decided in favour
of the latter; but still the fact requires to be explained
why the presence of two metals, as well as a process of
oxydation or chemical change in one of them, is almost
essential to the transmission of a current, or- at least the
accumulation of electric power.
Now, first, since by the hypothesis the ethereal pressure permeates all bodies, and serves to isolate the
chemical atoms from each other, a limited series of conductors, where the ether can pass with comparative ease
from one atom to the next, need to be in equilibrium with




1 72           ON MATTER AND ETHER.
regard to all these atomic pressures, and the resulting distribution of the attached ether.  When no force is at
work in any part of the circuit, which exceeds the coercing
power of atoms on their own outmost ether monads, there
will be no electro-msotion or current. But when this force
acts at any part, so as to cause a new distribution, there
will be a new condition of equilibrium propagated throughout the circuit; and it is plain that the disturbance by
chemical union in one part of the circuit will be most
simply neutralized by an answering amount of disunion
or decomposition on the opposite side.
Let us now conceive two diverse atoms in this circuit
to be brought near together; one with more rapid rotation,
but a smaller amount of attached ether, the other revolving
slowly or nearly at rest, but charged positively, in the same
proportion, with repulsive ether. They will have a strong
tendency to combine by their mutual affinity. Three or
four effects must ensue. The swifter revolution will be
lowered, and the slower increased, that the compound atom
may assume a common velocity. But the pressure which
separated them having  ceased by their union, a corresponding amount of repulsive force must be set free, and dispose
itself, under the form of ether, released from the positive
atom, to find a new equilibrium through the circuit. But
since the rotation of the negative atom has been destroyed
to that amount by the union, the immediate defect of
equilibrium is on that side, and the released ether must set
out in that direction. On the other hand, the increased
rotation of the zinc in combining, will tend to diffuse itself
on the other side, and produce a loosening, to the same
amount, of the attached ether. Thus a repulsive force,
equivalent to the separating pressure, which is removed by




CHAPTER X.                   173
the union of the two atoms, will travel round the circuit,
on one side, in the shape of transmitted ether, and on the
other in the shape of increased atomic motion. When
the reunion is effected by metal wires alone, without an
electrolyte fluid, the metal will resume its normal state,
intermediate between the extremes of accumulated ether
and increased rotation, and the surplus pressure or repulsive force will manifest itself in the form of sensible heat,
or the repulsive action of the atoms, in contrast to that of
their component monads. But when an electrolyte is interposed, the positive pole will attract the negative, and
the negative pole the positive element, nearest to it, while
the tension or pressure will thrust away the other halves
of the two compounds, which will either reunite in the
path of the circuit, or be propelled onward till they reach
the opposite poles. The view of Grotthus, which supposes
a decomposition and recomposition of all the atoms in the
route of the circuit, seems open to the objection, that these
changes could not begin till the electrolytic force has
spent itself in dividing the terminal atoms, and there is no
power left by which the separated oxygen or hydrogen
atom could repel the like atom already combined from its
actual union. The chief transporting power will be from
the positive towards the negative pole, in the direction in
which the ether travels; and this change has been established by a series of curious and delicate experiments.
(De la live, II. pp. 424 —442.)
The effect, then, of the completing of a voltaic circuit
through good conductors, and in one limited direction,
may be compared with that on a vessel of water, supplied
by a siphon from a reservoir nearly level with its brim,
and in which there are many minute apertures, through




174            ON MATTER AND ETHER.
which the water oozes slowly, when a hole, rather less
than the siphon, is opened near its base. The supply increases with the more rapid efflux, and the downward current thus formed diminishes the literal escape by the small
orifices, so that the current is almost wholly in the new
direction. Before the circuit is closed, the surplus ether
of the chemical union must find some outlet, either by imperfect and slow conduction, or by conversion into atomic
heat; and the reaction thus caused will hinder the rapidity
of the action itself. But as soon as the circuit is formed,
an outlet is provided for the ethereal pressure, which enables the chemical affinities to exert their full power in
bringing about the new combinations.
119. The two main conditions on which the formation
of the voltaic current depends are the chemical action of
the liquid on the oxydable metal, and the contact of two
different metals. In the explanation of Volta, the chief
influence was attached to the latter; while in the chemical
theory of Fabroni, Wollaston, Faraday, and De la Rive,
the main cause is held to be the chemical action. But
perhaps in this view, which has replaced the other, the
office fulfilled by the contact of the two metals has hardly
sufficient prominence, being, in all ordinary cases, no less
essential than the chemical agency itself.  On the other
hand, the opinion that mere contact can be an unfailing
source of electric power is disproved by facts, and does
violence to one of the plainest mechanical laws.
On the present view the explanation of the effect of this
contact seems very simple.  It is a determinant of the
direction in which two opposite forms of repulsion shall
travel, excess of ether, and increased rotatory motion. By
the hypothesis, the more negative metal, or copper in the




CHAPTER X.                   175
usual pair, has the greater vis viva of rotation. Hence copper and zinc in contact, or soldered together, must both suffer a constraint, and depart from their normal state at the
points of contact. The copper will have less, and the zinc
more atomic motion. There will thus be a tendency of the
copper to receive more ether, in compensation of diminished
rotation, and of the zinc, to part with some of its ether,
because its rotation is increased. At the same time, this
increase of rotation predisposes it to unite more readily
with oxygen, of which the rate of motion is assumed to be
still higher. Thus the chemical change alone supplies the
electrolytic energy; but the atomic contact of the oxygen
with the zinc, and of the zinc with the copper, have an
equal part in deciding the distribution of the liberated
energy under two distinct and opposite forms.




CHAPTER XI.
ON ELECTRO-MAGNETIS5M.
120. AN electric current, passing between the poles
of a voltaic battery, has the directive power of a magnetic
needle.  When the current passes above the needle from
north to south, the north pole of the needle is turned to
the east; and the direction is reversed, when either- the
direction of the current, or the position of the needle is
reversed also.  A magnet, in its turn, acts on a moveable electric current, and tends to make it assume a transverse position. Electric currents, again, when disposed in
spirals, act on each other and on magnets like natural
magnets, or like poles repel and unlike attract each other.
The action of the earth, also, or its directive power on
natural magnets and on such artificial magnets, formed
of spiral currents, is exactly the same.
These phenomena, first opened to view by the discovery of Oersted, anld more fully developed by Ampere,
have given rise to two or three slightly different explications.  The most widely received is that of Ampere.  He
assumes that magnetism consists in a special arrangement
of the atoms of magnetic bodies, by which electric currents constantly circulate around them. From the date




CHAPTER XI.                   177
supplied by experiment with regard to the mutual action
of currents, three laws are deduced; that two currents
moving the same way, parallel to each other, and at right
angles to the joining line, attract each other; that, moving
oppositely, they repel with equal force; and that, moving
in the direction of the joining line, they repel with half
the force. From these laws is deduced the action of closed
or open currents on each other; and nearly all the varieties
of magnetic action are also explained, if it be admitted
that circular or spiral currents are moving constantly, in a
certain specified direction, around their molecules or atoms.
Others have conceived of the relation between the
current and magnetism in a different way.  Oersted himself seems to have supposed that the conflict of two electricities, in the current where they meet, gives them a spiral
direction, so as to act on the magnet at right angles to the
direction of the wire.  Mir Barlow, also, has reduced the
whole theory to one single assumption, that "every particle of galvanic fluid in the wire acts on every particle
of the magnetic fluid in the magnet, inversely as the
square of the distance, but with a tangential force, which
tends to place each at right angles to the other, and to the
line of junction."
121. So far as this statement assumes two different
fluids, one galvanic, the other magnetic, it is plainly more
cumbrous than that of Ampbre, which admits an electric
fluid alone. But viewed merely as an expression of the mechanical relation between the magnet and the current, it
seems to present it in its simplest form.  On the other
hand, it does not seem to explain directly the mode of action
of one electric current on another.
The view of Ampbre may claim, in two respects, a
12




178            ON MATTER AND ETHER.
superior simplicity.  It dispenses altogether with a magnetic, as distinct from an electric fluid; and refers consistently to one common principle, the action of a current
on a current, a current on a magnet, a magnet on a current, of the earth on magnets or currents, and of two natural or artificial magnets on each other.  But its gain in
these respects is partly balanced by a serious loss. The
three laws from which it starts are not simpler in themselves than the one law assumed in the other view, and
have just as little the appearance of being primitive laws,
and not secondary results of some still undetected cause.
The assumption that one or two fluids, by the mere
fact of moving in certain directions, gave rise to three
laws of angular force, by which they act on the same fluid,
but only when in motion, is harsh and violent. Again,
as IMr Barlow has observed, "it is an immense demand
on the reader to request him to admit an infinitude of
infinitely small currents, perpetually circulating within
the solid mass of magnet or a steel bar." We may go furtlier, and say that the assumption contradicts the definition of an electric current, as deduced from the only cases
of which we have knowledge.  For the current, either in
the earth, or in the voltaic battery, plainly requires distinct
masses, of a countless number of atoms, capable, by distinct
chemical qualities, of receiving an opposite excitation. To
transfer it to the ultimate atoms themselves reverses thus
one essential condition, on which its formation in all known
cases depends; and if the atoms are further assumed to be
solid spheres, as Ampbre and most others have done, the
contrast amounts to a direct contradiction.  To justify the
hypothesis, we should have to assume chemical union and
separation constantly in progress on opposite sides of the




CHAPTER XI.                   179
magnetic atoms themselves, or else currents circulating
constantly with no possible cause of excitation.
A true explanation cannot wholly supersede either of
these diverse, but nearly related theories, which have
succeeded equally in grouping together large classes of
facts, and in assigning the chief mathematical laws on which
they depend. The test of its success must lie in reconciling them together, in freeing each of them from hypothetical elements, which disfigure them, and referring them
alike to clear and definite mechanical laws, dependent on
the very constitution of matter and ether. Let us see
whether this important end will not be attained by the
adoption of the present theory.
122.  Since neither the atoms of bodies, nor the ether
of space and of the air is in a state of rest, and they are
linked together by a law of high repulsive power, it is
plain that a continual transfer of vis viva must be carried
from one part to another; and these changes must counteract each other in a state of equilibrlum  or permanent
motion, like the transfer of caloric in bodies of the same
temperature, on the old theory of a calorific fluid. If any
kind of permanent motion is set up in this ether in a
given direction, it must have some action upon all the surrounding ether. And if the motions of any part of this
ether are linked with a certain portion of matter, itself
moveable, the attractive, repulsive, and directive power
will plainly be communicated from one to the other.
Whatever action of this kind occurs, since it consists
in a transfer of vis viva through a perfectly elastic medium, it is plain that it will be inversely as the square of
the distance, for elements having the same kind of motion,
and the same angular relations, and differing in distance
12-2




180            ON MATTER AND ETHER.
alone. At the same time, the dependence of this effect on
angular position, and on the direction of the motion, will
shew its derivative character, and distinguish it from a
proper central force, like that of gravitation.
Again, since the force must result from small displacements, and these infinitesimal compared with all sensible
distances, the effect must be linear, or the law of composition of forces must apply, and the total effect be capable of
resolution into three directions at right angles to each other.
Again, the law of repulsion in the ether, the infinitesimal distance of its monads, and the great increase of
repulsion on the least departure from the mean place of
equilibrium, imply the existence of lines of equal force or
repulsion, radiating from every monad to every other,
however distant, and that the transmitted repulsion is
equal, at whatever distance, along these lines.
The motion of any such monad is, in its effect on any
other monads, as a source of vis viva, and not a mere centre
of force, the transfer of one of these lines of force from a
first direction to another infinitely near. It is measured,
then, by the union of an attraction, represented by the first
line, and a repulsion in the direction of the second, equal
to the first when the motion is at right angles, but greater
or less, when it inclines to or from the second monad, by
the law of the inverse square. Hence, in the simplest
case, the action on a monad at right angles to the direction
of the motion will tend to move it in precisely the contrary
direction, with a force inversely as the square of the distance.
If, however, the ether acting and acted on be grouped
around material atoms, the motion will probably, however
swift, be rhythmical, and depend on the intervals of the
atoms, and in travelling the space of one such atom, act as




CHAPTER XI.                   181
a couple, being withdrawn on one side of the distant atom,
and replaced on the other.  It will thus have a direct force
to turn the atom round an axis at right angles to the
joining line, and to the direction of the first motion, so
that the equatorial movement, on the near side, may be in
the same direction with the inducing motion.
In general, the mechanical effect of any atomic movement of translation, transmitted through the ethereal
medium to a distance, must be twofold, each inversely as
the square of the distance. The part which is at right
angles to the joining line is a force of initial rotation,
backward with reference to the resolved part of the primitive movement.  The other part is a repulsion in the
direction of the joining line, when the motions meet, or are
opposite, and an equal attraction, by the removal of a
mean repulsion in the state of rest, when the motions concur
or lie the same way.  But for these effects to be manifest,
or reveal itself in material motion, there must be two series
or systems of material particles, one exciting, and one
excited, which are linked by some fixed law of connection
with the ethereal motions.
123. From these axioms, which seem to be necessary
mechanical consequences of the assumed laws of repulsion
and affinity in ether and matter, these results seem at
once to follow.  First, two parallel electric currents,
moving the same way, will attract each other, since each
will tend to revolve towards the other, in the direction of
the slant lines, and the forward and backward tendencies
in two equal, parallel lengths, will neutralize each other,
leaving an attractive force alone. Secondly, two currents,
parallel, and moving oppositely, will repel each other for
the same reason.  Thirdly, motion along the line of june



182            ON MATTER AND ETHER.
tion will also be attractive in its tendency, when both
move the same way, and repulsive when the motions meet,
so far as it depends on the general law of transmitted
motion. But both of these theoretic effects will probably
be insensible, because action in the very line of motion
must depend on the primary law which decides the formation of the current, and on the conducting power, and not
on a secondary effect alone, which could only be transmitted through the moving ether itself, and would cease,
if the exciting motion be as swift as the ethereal transmission.
124. From the same principles, the relation between
the electric current and the magnet, flows at once, without
any need to invent electric currents, properly so called,
circulating around all the magnetic atoms. To see this
clearly, we have only to reflect on the nature of a magnet,
and of the current, freed from hypothesis, and reduced to
its simplest definition.
A magnet, then, has two poles, a north and a south,
facing opposite ways, and like poles repel, and unlike
poles attract each other. A revolving atom, in like manner, has two poles, a north and a south, if we name that
pole towards which the motion reverses that of a watch,
the north pole, and that on the side where the motion is
like that of a watch, the south pole. By the general principle of the congruence and disagreement of motions, like
poles of such atoms must repel, and unlike poles attract
each other. The attraction and repulsion, also, depending
on the greater or less amount of vis viva transmitted
through the ether, vwhen the motions of rotation concur or
oppose, must vary as the inverse square of the distance.
Every revolving atom, constructed as the present theory




CHAPTER XI.                  1 S3
requires, is thus all elementary magnet by its very structure and rotation, without requiring the foreign conception
of currents from without circulating around it. Any substance in which the atoms not only revolve, but are
capable of being disposed with a large excess of poles
directed lengthwise and on the same side, will be magnetizable, and if there be a coercive power to retain the
poles, when once thus arranged, in their new position, it
will have all the characters of a permanent magnet.
Again, while the relation between the two opposite
faces of a revolving atom is plainly the same as between
the poles of a magnet, the relation between the axis and
the equator of rotation is precisely the same which exists
between a magnet and an electric current. One is at right
angles to the other. One has two opposite faces, according to the direction of the rotation, the other a direct
movement of translation in the line of the tangent. By
the principles of mechanics, an ether current, moving along
in a medium  with lines of equal force, will tend to
produce a movement of rotation round an axis at right
angles to its own course, and the joining line. In other
words, it will tend to magnetize bodies that are magnetizable,
by inducing rotations of the particles with the axes in that
position. Conversely, where the body is magnetic, or a
fixed relation established between the north poles, and
the direction of the magnetic body, there must be an equal
force exerted to turn the body into such a position, that
the movement of these equators and of the current may
agree together. Now this is precisely the law which defines the directive power that magnets and electric currents
exert upon each other.  We have simply to assume that
the north pole in a magnet is that away from us when the




184            ON MATTER AND ETHER.
motion is that of a watch, or which answers to the north
pole of the earth itself, and then all the consequences agree
with the supposition, the positive pole of the battery being
assumed also to be the source of the ether current.  Thus,
when the current is from north to south, a magnet beneath
it will have its equatorial motion southward, or the north
will answer to the earth's west, the south to the earth's
east, and by consequence, the east to the earth's north; or
the north pole of the magnet must turn eastward, to produce mechanical agreement between the two directions of
motion.
125. The phenomena of electro-magnetic induction
seem to admit of a simple mechanical explanation by the
same theory. For the first effect of a current newly begun,
by the law of mechanics just stated, must be to produce a
reaction in a parallel wire, depending on their distance and
the energy of the first current. But this current, having no
sustaining cause, must cease by the reaction of its own
momentary effort, and the general inertia of the atoms,
and the ether of the wire be in a new state of equilibrium.
The cessation of the first current, being an equivalent
change to the creation of an opposite current, will plainly
have the same effect, and induce for the moment a current
in the same direction as that which ceases. These are
precisely the facts which have been brought to light in the
last thirty years, and received so wide a variety of practical applications.
126. All the main features, then, of Electro-magnetism, the attraction of two parallel currents moving the
same way, and their repulsion, when moving opposite
ways, the main basis of Ampere's theory; the mutual
influence of a current on a magnet, and a magnet on a




CHAPTER XI.                  185
current, and of spiral currents on each other; the directive
law, by which a magnet and a current place themselves
at right angles, the one basis of Mr Barlow's theory; and
the inductive power of a current, when first formed, and
when broken again;-all find a direct and simple explanation, on mechanical principles, in the present theory. The
fundamental law on which they rest is simply this, that
permanent ethereal motion, in a medium where there is
uniform repulsive force, or lines of force in all directions of
constant value, tends to diffuse itself in all directions by
the vis viva, to an amount inversely as the square of the
distance; that like motions attract and unlike motions
repel; and further that, by the couples which result directly from the motion, there is a directive force of similar
amount, which tends to make rectilinear and equatorial
movements concur in direction with each other. There is
thus no need whatever to introduce supposititious electric
currents, distinct from the magnetic atoms, and moving
around them, to account for the phenomena. The rotation
of the atoms themselves, which alone makes them polar
and magnetic, is enough to explain the directive force
exercised by magnets and by currents. The substance
of the theory is retained, but imaginary vortices like those
of Descartes, which only encumber it, are swept away.
127. This explanation requires, perhaps, one or two
corrections to be made in the alleged laws on which
Ampbre. has founded his theory of magnetism.  The
experimental cases on which the theory is founded are
these:
(1) " Two equal and contrary finite currents exercise
on a third, situated at the same distance from the two
former, no action, the attraction and repulsion being equal."




186            ON MATTER ANiD ETHER.
This equal and contrary action results equally from the
present conception of the mechanical effect, and is indeed
almost self-evident in any view.
(2) " The action of a rectilinear current on a moveable
conductor, is equal to that of a conductor bent and turned
in any way, but between the same limits, the currents
being of the same intensity."
This law requires, for its truth, that the sinuosities are
small compared with the distance. In this case, neglecting
quantities of the second order, it results evidently from the
mode of mechanical action, and the equality of action in
contrary directions.
(3) "A closed circuit cannot set in motion any portion
of a current forming an are of a circle of which the centre
is on a fixed axis, around which it may freely turn, an
axis perpendicular to the plane of the circle to which- the
axis belongs."
This seems to result at once from the nature of the
mechanical force, in the present theory. For the motion of
the exciting current acts on each element of the excited
body only through the ether which it contains, and the
reaction arising from the law of their union.  Hence the
only possible action in the direction of the element will be
to increase or diminish the intensity of the current, or
to have a slight accelerating or retarding power.  The
fourth case of equilibrium, between proportional conductors,
similarly placed, resolves itself into the general law of the
inverse square, and the general properties of space.
128. From this last case of equilibrium, however, the
conclusion has been drawn by Ampere, and is given in
Murphy (Electr. p. 113), that two portions of a current,
moving in the direction of the line which joins them,




CHAPTER XI.                     187
repel each other with just one half the force of their attraction, when they move parallel at right angles to the
line of junction. This conclusion is drawn by an ingenious process of analysis, and it is inferred that this relation is necessary, in order that the total action on each
element of the second current may vanish irrespective of
the shape or distance of the first.
This reasoning, I conceive, involves a fundamental
sophism, disguised by the ingenuity of the analytical process, and the apparent simplicity of the result to which it
leads. Let us suppose any forces to act on a circular metal
pipe, not directly, but by means of their action on a current
of water which fills the pipe, and circulates within it.  It
is plain that they can only accelerate or retard the current,
so far as they act in its direction, and can only tend to
move the pipe, so far as they act on the current at right
angles to its course, so as to produce a reaction on the
upper or under, the nearer or further side of the pipe itself.
But if the direct action on any part of the conductor in the
direction of the current is null by the conditions of the
problem, and can only result from the action in other parts
of it, and the cohesion of the parts in a solid conductor,
then the analysis is misdirected, and the supposed consequence fails.
Again, the law which results from this analysis has
another presumption adverse to its truth, from the singular
conclusion to which it leads. It implies that the attraction
of one element on another is
2 (sin 0 sin 0' cos  -  cos 0 cos 0'),
where r is the distance, b the angle of their two planes,




188            ON MATTER AND ETHER.
and 0, 0' the angles of each element with the joining line.
Assuming    0 = O and 0 = 0, we have.1       1    2 0)
1 (sin2 0  - os2 )
2
for the attraction of two parallel, elements which make an
angle 0 with the line of their centres.  This implies a neutral state of complete equilibrium, when the elements make
an angle of 353. 16' with the joining line, an attraction at
greater angles, and a repulsion at less. But it is hard to
believe that two currents, whatever their precise nature,
should be neutral and indifterent at this angle, and at no
other, which is the necessary result of Ampere's formula.
Still further, the conclusion, which also! follows, that
two parts of currents, when moving in the line of junction,
repel when the motions are similar, and attract when they
are opposite, is in its own nature highly improbable.
Every mechanical conception would point to an opposite
relation, of attraction when the motions are similar, and of
repulsion when they are opposite. The indirect evidence,
from analysis, it has just been shewn, gives no real warrant for this paradoxical conclusion.
129.  rT'wo experiments are mentioned in De la Rive,
I. p. 230, as confirming this law of repulsion of similar
currents in the direct line. The first is when a part of the
conductor, like a horse-shoe, rests on a bridge between two
semicircles, dipping into mercury on each side, and on
communication being made, with the fixed part of the conducting circuit, through the mercury, the horse-shoe recedes along the bridge. This is supposed to prove that
each half is repelled by the current in its own line. But
it is a simpler solution to suppose that each side is repelled




CHAPTER XI.                  189
by the alternate part of the current, where the directions
of motion are opposite, and not the same; or that there is
direct ethereal repulsion on one side, and reaction on the
other, at the points where the current enters and leaves the
moveable part of the circuit.
Again, the motions caused in a capsule of mercury,
through which a current passes by two ends of platinum
wires, are supposed to prove the same law. But these,
also, seem capable of a simpler and more natural explanation by the direct repulsion of the ether on the material
atoms of the liquid conductor through which it is passing,
which must be of the same kind as its heating effect in
passing through solid wires.
All the main phenomena, then, of electro-magnetism
appear to be solved, by the present theory, on mechanical
principles, or the transmission of vis viva through a highly
repulsive medium, and the consequent tendency to symmetry of permanent motions,,whether of translation or
rotation. There is no need to introduce a cumbrous hypothesis, like the vortices of Descartes, of countless electric
currents, distinct from the magnetic atoms, and constantly
circulating around them, without any assignable cause for
their existence, and in the entire absence of one main condition, the contrast of two or three kinds of compound
structure, on which that existence, in every known case,
appears to depend.




CHAPTER XII.
ON MAGNETISM AND DIAMAGNETISM.
130. THE recent discovery of the division of all substances into magnetic and diamagnetic, or those which
arrange themselves axially or equatorially between the
poles of a powerful magnet, has opened a new and difficult
field of inquiry. This is rendered more perplexing by
the further discovery, still more recent, that magnetic or
diamagnetic substances may be either in a normal or
abnormal state; and that in the abnormal state, magnetic
bodies behave as if diamagnetic, and diamagnetic as magnetic. The order of magnetic power is as follows, beginning with iron, the most powerfully magnetic, and ending
with bismuth, which, in a lower degree, takes the lead in
diamagnetic power.
Iron, nickel, cobalt, manganese, chromium, cerium,
titanium, palladium, crown glass, platinum. Arsenic, ether,
alcohol, gold, copper, silver, lead, water, mercury, sodium,
flint glass, cadmium, tin, zinc, heavy glass, antimony,
phosphorus, bismuth.
Among diamagnetics are also included rock crystal,
many non-metallic salts, iodide of phosphorus, sulphur,




CHAPTER XII.                  191
resin, cooked or raw meat, blood, feathers, a piece of apple
or pear. Among the gases, oxygen is strongly magnetic.
These lists shew how widely the magnetic varies from the
electric or voltaic order of the simple elements. Thus
oxygen is magnetic, and sulphur and phosphorus diamagnetic; platinum  and palladium  magnetic, and gold
and silver diamagnetic; iron, nickel, and cobalt magnetic,
and zinc diamagnetic.  The first of these are taken from
the electro-negative, the second from the intermediate, and
the third from the electro-positive elements.
131.  The following explanation, by Professor De la
tive, is perhaps one of the latest proposed.
A[agnetic bodies are those which have most atoms in
the same space, and a low conducting power for electricity;
and the diamagnetic have fewer atoms, or else a greater
conducting power. In the isolated atoms the electricity,
excited at one pole, passes by the surface to join the
opposite kind, and returns by the axis. When a number
of such atoms are disposed near together, in a circle, with
like poles the same way, they form a molecular circuit,
and have an electric current on their outer side. For this
purpose it must be composed of atoms very near together.
But "in order that the current may be formed round the
molecule, it is not only necessary that the atoms be very
near together, but that they be not sufficiently conductible
to enable the two electricities, accumulated at their poles,
easily to unite by their surface, rather than to unite with
the contrary electricities of the two atoms, between which
each of them  is interposed."  Thus copper and  zinc,
though with nearly as many atoms as iron in the same
space, are supposed to be diamagnetic, because of their
higher conducting power for electricity.




192            ON MATTER AND ETHER.
Several weighty objections seem to lie against this
attempted solution. It is complex enough in itself, to
assume, with AmpBre, that electric currents are revolving
constantly around all the chemical atoms; since an exciting cause, like that which results in the voltaic circuit
from the chemical union of vast numbers of them, can
have no existence in the case of the single atoms themselves. It is a further complication, to suppose that these
spherical atoms, which determine the chemical constitution, are themselves composed of an infinity of smaller
atoms, permeated by an electric fluid, so that a current can
travel along the surface in one direction, and along the
diameter in the other. It is a third degree of complication
that these currents, by Ampbre's hypothesis, besides continually separating and reuniting, without and within the
atom, with no apparent cause, act on each other doubly,
first as centres of force by the laws of static electricity, and
secondly, by the mere fact of their motion, by rather complex laws. It is a further remove from simplicity, to
suppose that these chemical atoms, even with all this complicated apparatus of external and internal currents, do
not build up directly the structure of bodies, but must first
be combined into molecules of an uncertain number of
atoms, on which molecules alone the magnetic qualities
really depend. A theory loaded with all these assumptions, however ingenious it may be, or whatever classes of
facts it may partially explain, can have very small claim
to be the true interpretation of the facts, or a faithful reflection of the simplicity of natural laws.
132. There are two other fatal objections which seem
to lie against Professor De la Rive's solution.
First, if iron (ii. p. 68) has 230 atoms in the same




CHAPTER XII.                  193
space in which gold and silver have 150, the linear excess
of atomic density will be as 6 to 7. But since this refers
to the whole space which belongs to the atom of iron, and
of gold or silver, or to the mean distance of the centres, the
natural inference will be that the surfaces of the gold and
silver atoms, and not of those of iron, are nearest together.
For even if we double the usual atomic number of iron,
still the silver atom has nearly double, and that of gold
nearly four times its weight, so that the radii of their
spheres, if equally dense, would have a larger ratio than 7
to 6. On the other hand, to assume uncertain varieties of
density in these spherical atoms complicates the whole
hypothesis still further. The presumption, then, must be,
on this view, that the surfaces of the gold and silver atoms
are nearer together than those of iron, which just reverses
the required condition.
Again, the more conductive metals are supposed to be
diamagnetic, in spite of their density; because this conductivity "enables the electricities, accumulated at their
two poles, easily to unite by means of their surface, even
when insulated, rather than to unite with the contrary
electricities of the two nearest atoms." In other words,
the conductivity assumed in the hypothesis is one which
conducts electricity along the surface of the same atom, in
preference to its passage fiom one atom to another. But
the conductive power, which alone is revealed by experiment, and by which the metals are classed, is exactly the
reverse, and expresses the facility with which the electricity passes from one atom to another, and thus can reach
distant parts of the whole mass. A graduated conductivity
along the surface of the same atom is a pure hypothesis,
of which experience has told and can tell us nothing.
13




194           ON MATTER AND ETHER.
Hence both the causes offered for the diamagnetism of
gold and silver, in the view now examined, would seem to
imply the exact reverse, and prove them more magnetic
than iron; because the surfaces of their atoms, if spherical,
must probably be nearer together, and their greater conductivity from  one atom  to another would make the
formation of the supposed molecular circuits more easy.
These appear to me two fatal objections to the theory,
besides the immense complexity of the atomic structure
which it implies, and the total absence of any key to the
nature and formation of these anomalous atomic currents.
134. Let us now endeavour to trace the results of
the present theory.
First, every revolving atom, by its very structure, will
be an elementary magnet. Since it resembles a cycle or a
cylinder, more nearly than a sphere, it will have a natural
axis of rotation, and its units, being a reunion of matter
and ether, will have an action, as ether monads, on the
attached and free ether; while the repulsion of the free
ether, being everywhere the same, and in all directions,
implies lines of equal force, which are variously affected
by every atomic motion. Again, unlike poles, when they
face each other, imply a concurrent motion, which they
must tend to impress on the intervening ether, producing
a radial repulsion at right angles to the joining line,
and an axial attraction in the line, from a partial exhaustion of the ether, a cylindrical eddy, and imperfect
ether vacuum. A magnetized body must be one in which
the atoms rotate habitually, and where poles of the same
kind are disposed, by a decided predominance, in the direction of the length towards one end.
Let us now suppose a body not magnetized, not even




CHAPTER XII,                   195
naturally magnetic, to be placed between the poles of a
powerful magnet. The law of assimilation of motion in
the last chapter will imply, as its necessary result, that
there will be a strong tendency to create a rotatory motion
in the attoms of this body, agreeing with the rotation of
the atoms in the direction of the two poles. If the atoms
rotate already, the tendency will be to turn them, so that
the chief amount of rotatory motion may lie in the line
of the magnetic influence.  If previously almost at rest,
or simply oscillating, the tendency will be to make thema
rotate, so that the polarity may be the least disturbed; that
is, around the main axis, if the ends have a strong polar
attraction, and the sides are nearly indifferent; or at right
angles, if the ends have only a slight, and the sides an
angular polarity. In general, the greatest amount of concurrent motion will be when the length of the body is
placed in the direction of the magnetic poles; and accordingly, the majority of bodies have, in this sense, magnetic
properties, or a tendency to place themselves lengthwise,
and not transversely, between the poles of a real magnet.
135. Three conditions, then, seem  required in the
chemical atom, to ensure a great magnetic susceptibility;
an axial structure, so that the cohesion shall be mainly by
the ends rather than the sides; the absence of lateral
polarity, or a form nearly cylindrical, and the union of
cohesive fixity of axis with a large moment of rotation.
These conditions are, in part, opposed to each other, so
that their union in the required proportions may easily be
conceived to be rare. We may thus explain, perhaps, the
singular fact, that only three of all the fifty or sixty elements have strong capabilities of magnetic action.
Any suggestion in detail must be only conjectural in
13-2




196            ON MATTER AND ETHER.
the present stage of the theory. Subject to this needful
reserve, there seems an easy way of reconciling these conditions with the known properties of iron and its atomic
number. This is given at exactly 28 in all the approved
lists, and suggests at once an arrangement in four sevens
as the simplest explanation. Let us conceive, then, four
cycles, with one central, and six outer atoms, to constitute
the element of iron. Apart from compression of the ether
and the remoter units, and supposing the cycles vertically superposed, this atom will be a minute cylinder,
of which the height is three times, and the breadth twice
the neutral distance.  Its sides will be nearly circular, or
strictly hexagonal, and its ends will have a strong polarity.
The ethereal pressure will force all the units of each cycle
within the neutral distance, unless compensated by centrifugal force. Hence it seems easy to conceive a tendency
to assume such a rotation, from  the constant struggle
between the pressure of the outward ether, and the developed repulsion of the component monads, as may keep the
particles at the neutral distance, when the centrifugal force
must just balance the ethereal pressure. In this case all
the required conditions for a high degree of magnetic susceptibility seem to be fulfilled.
136. The magnetic power of iron is increased by
heating it, up to a red heat. Beyond that limit it rapidly
diminishes. This agrees perfectly with the present theory.
For the first effect of increased temperature must be to
increase the velocity of the rotation, and thus to add to
the magnetic power, which depends on the axial rotation
alone. But when the luminous limit is reached, the ends
must be conceived to oscillate laterally, and the cohesion
to diminish up to the point of fusion. Hence the magnetic




CHAPTER XII.                  197
force must be weakened, and disappear, as soon as the
atom begins to revolve on an equatorial axis, where
fusion also begins. For though inductive magnetism may
be shared by liquids and gases, magnetism proper is confined to solids alone.
137.. Diamagnetism, in this view, depends on such
a structure of the atoms as disposes their equators, rather
than their poles of revolution, to arrange themselves in
the direction of the length of the mass. The form which
seems most favourable to this arrangement is the flat cylinder, of which the diameter exceeds the height.  The same
result may occur, in a lower degree, when the moments of
rotation at right angles are nearly equal, and there is still
a slight oblateness, or truncation of the ends, so that the
equators predominate in the length, and the poles in the
breadth of the substance. A third case may include those
axial atoms, in which the length exceeds the breadth, but
there is lateral polarity, and a less than usual adhesion at
the ends. The first description may belong to diamagnetics, like arsenic and antimony and phosphorus, which
are strongly electro-negative; the second to those intermediate in their electric order, as gold, silver, mercury;
and the last to the electro-positive, such as zinc and
sodium. The explanation, in this general shape, appears
to reduce the phenomenon to its simplest interpretation;
and the theory with regard to the composite structure of
the chemical atoms provides a cause plainly adequate to
produce effects of the kind which scientific experiments
have revealed.
138. Bismuth is the most powerful of diamagnetic
elements. Its density is 9'82, or nearly equal to that of
silver, and one half that of gold.  Its atomic number,




198             ON MATTER AND ETHER.
formerly rated at 71, is now often taken at three times the
amount, or 213, while the specific heat would lead to a
number half this amount, or 106~.  If we assume it to
consist, like iron, of four planes or cycles, each of them,
according to the value assumed, will have 18, 27, or 54
units.  NWe may easily, then, conceive its structure to be
some slightly modified form of a flat cylinder. Now bismuth " in structure is highly lamellated. It is brittle when
cold, but may be hammered into plates while warm.  At
476~ it fuses and sublimes in close vessels at a red heat.
It is a less perfect conductor of heat than most other
metals." All these features agree perfectly with the hypothesis of a flatness in the structure of the atoms.  The
metal is also wanting in ductility, which is another contrast to the properties of iron. On the other hand, its'low
conducting power for heat, and also for electricity, stands
in diametrical opposition to the hypothesis which explains
the diamagnetism of copper and silver by their conducting
power.  For the conductive power of bismuth is fifty
times less than that of silver, and six times less than
that of iron; while its atomic density, in the highest estimate, is more than half that of silver, and in the lower
estimates, of 71, or 1061-, is actually greater.  So that, on
the principles of the theory, its diamagnetism ought to be
much less, instead of being far more powerful.  But, on
the present view, a lamellated structure and fusibility, or
else a high electric order, should mark diamagnetics;  and
bismuth has the first two properties in a high degree.
139.  Antimony is the next metal in diamagnetic
order.  Now this stands high in the electric series. It has
also a large atomic number, and on both accounts must be
conceived to have a radial and not an axial structure.




CHAPTER XII.                  199
Again, it is "a brittle metal, fuses at 8100, and on cooling
acquires a highly lamellated structure, and is volatile at an
intense temperature" (Turner, p. 493). It is wanting both
in ductility and tenacity. All these characters, as in the
last metal, agree perfectly with the supposition of the flat
form of its atoms, and of a cohesion by the edges rather
than the flat sides or ends.
140. Zinc, the third diamagnetic metal, lies much
lower than the two others, and especially than antimony
and arsenic, in the voltaic scale. Its atomic number, also,
is 32'5, or only slightly greater than that of iron, nickel,
and cobalt, the magnetic metals. Its electro-positive character is very conspicuous, being constantly employed, in
the electric circuit, for the positive element, and capable of
very easy oxidation.
These properties are rather anomalous, and make it
less easy to conjecture a form  of the atom, which will
satisfy all the conditions.  But still other properties agree
well with the theory. " Its texture is lamellated; at low or
high degrees of heat it is brittle; but at temperatures between 210~ and 5000 it is malleable and ductile, which
enables it to be rolled or hammered into sheets of considerable thinness."  It may perhaps be a question that still
requires to be settled, whether the diamagnetism of zinc
belongs to it at all temperatures, or whether it is not a
variable quality, capable of reversal, when the temperature
is varied between the above limits.
141.  Tin and cadmium are the two next diamagnetic
metals.  Their atoms 58 and 56 are nearly of the same
value. In electric order, tin is just above and cadmium
below the three magnetic metals.  The two metals resemble each other.  Cadmium is both ductile and malleable;




200            ON MATTER AND ETHER.
tin is malleable, but of much lower ductility. They both
fuse at 4420. Tin " is soft and inelastic, and when bent
emits a peculiar crackling noise." These properties all
agree with the general conception of a lateral cohesion,
and a lamellated character, reversing the characters of iron
and platinum, or rendering the ductility of tin and cadmium inferior to their malleability.
142.  Gold, silver, and copper come near together in
electric order, and are also feebly diamagnetic. They are
also ductile and tenacious, and form  a sub-class quite
distinct from the previous metals. Their properties all
agree with the hypothesis that their breadth is slightly
in excess of their length, either in extent or angularity,
so as to admit only of a slight excess of polarity, either
way, in a bar or cylinder of the metal, but to render the
arrangement of the atoms more easy, when the equators
are more numerous than the poles in the direction of the
length.
143. Mercury, water, ether, and alcohol are all diamagnetic. These are the most characteristic liquids, mercury being the only fluid metal, and water the almost
universal solvent. The fluidity of mercury, and the weight
of its atom, imply that its axes and moments of rotation
are very nearly equal. In this case the mere fact of rotation, as a liquid, will give a slight oblateness to the compound atom, and will therefore dispose it to arrange its
equators, rather than its poles, in the line of greatest
length. Again, water, for the same reason, must be conceived to have its atoms revolving around the axis of greatest, not of least moment. Hence its composition will be
oblate and not prolate, and will be favourable to a disposition of the equators in the line of the length.  The




CHAPTER XII.                  201
question whether these substances are still diamagnetic
when hard frozen deserves, perhaps, a series of careful experiments.
144. While the leading liquids, water, mercury, and
alcohol are diamagnetic, oxygen is found to be strongly
magnetic; but other gases, except air and some compounds
of oxygen, are very nearly or altogether neutral. This
property of oxygen gas agrees fully with the hypothesis.
Its typical character, by the previous chapters, would seem
to be a flat cycle in rapid rotation. Its gaseous expansion
reverses the condition of a liquid, and enables its atoms to
move freely among each other, and to receive and retain,
under magnetic power, a partial parallelism with each
other, so that the equators shall be in the line of the
breadth, and the faces in that of the length; when in
solids the consequence would be the reverse, from the
want of room for the free adjustment of the poles, so that
the need of compact arrangement would place the equators in the line of the length. The neutrality of other
gases is less easy to explain. But if there is originally
a near balance of polar tendency, the magnetic influence
may be too weak to determine a fixed preponderance,
since all the particles are moving constantly around each
other, and thus tend to vary perpetually the direction of
"their poles.




CHAPTER XIII.
ON TERRESTRIAL PHYSICS IN GENERAL.
145.  THE doctrine that our present chemical elements
are compound, and mutually convertible under favourable
circumstances of extreme pressure or electric force, opens
a wide field of inquiry with regard to several classes of
phenomena, of which the causes have been hitherto unexplained.
All the varieties, which chemistry makes known to us,
on the present view, are the results of special arrangements
of centres of force; and are included between two extremes,
the free ether of planetary space, and the strong compression of the central portions of the sun, the earth, and the
other planets. Nature is thus like a tree of which the
roots are hidden from sight, deep towards the earth's centre, while its lightest blossoms are in the height of the
atmosphere, bordering on the ambient ether; and the stem,
the branches, and the foliage, are the various minerals of
the solid strata near the surface, and the liquid elements
and gases of the sea, the land, and the air.  Chemical
composition is included between these limits, and probably
disappears alike under the intense pressure near the centre




CHAPTER XIII.                  203
of the earth, and in the diffused and exceedingly rare matter which remains still uncondensed throughout the solar
system.
146. The Central Structure of the Earth is the first
main question, which has given rise to much speculation.
Its spheroidal shape has naturally led to the inference of
its former fluidity.  And since the temperature rises
steadily, as we descend into the deepest mines, it has
been a popular hypothesis that the whole mass of the
earth, even now, is liquid with heat below the depth of
thirty or forty miles. Of late this conclusion has been
questioned on astronomical grounds, and it has been inferred, from the phenomena of nutation, that a solid shell,
800 or 1000 miles in thickness, is required to satisfy the
mechanical conditions of this disturbance.
There is, however, a great oversight in the reasoning,
which infers the present fluidity of the central mass of the
earth from the rate of increase of temperature in mines.
For the point of fusion must plainly rise with the increase
of pressure, as the boiling-point is altered in liquids by the
same cause. But while both the pressure and the sensible
heat increase towards the centre, and have an opposite
tendency to cause and to hinder fusion, it is far more
natural to suppose that the pressure is the exciting cause
of the heat, than that both are quite independent, or heat
the cause of pressure. Now if the increase of temperature
is really a secondary result from the increase of pressure,
the natural consequence must be, that the parts next the
centre, where the pressure is greatest, must be solid and
not liquid; and that the liquefying power of the heat, if
it exist anywhere, must be confined to parts much nearer
to the surface, but too low for the solidifying power of the




204            ON MATTER AND ETHER.
cooling radiation from  the surface.  Even in the most
heated part it may well be doubted whether the normal
state is one of actual fluidity, and not rather of constrained
solidity under intense pressure, so as to produce instant
fusion, or even partial evaporation, whenever, from any
disturbing cause, that pressure is lessened or removed.
The Central Heat of the Earth, on the present view of
matter and ether, will be only a result of the pressure due
to its mutual gravity, and to the condensation, by which
the attached ether is forced outwards and upwards from the
parts nearest the centre. This extrusion of the ether will
counteract the effects of pressure in the parts nearer to the
surface, and may retain a considerable portion in a state of
igneous fluidity. But the surface itself is cooled by the radiation of heat into space, and hence becomes a solid crust.
The middle portion, whether actually fluid, or solid through
the pressure, must liquefy or turn into vapour if the pressure
be locally removed, and may thus give rise to all the phenomena of volcanic action.
147. Mineral Veins.
Some of the usual phenomena, very perplexing and
unaccountable on the usual hypothesis, find an easy explanation on the present view. The metals are rarely
found native in a metallic state, but in sulphurets, oxides,
sulphates, carbonates, or more complex combinations.
Some of them  appear to have a special friendship and
affinity, as silver is often found in ores of lead, and platinum, iridium, palladium  are derived generally from the
same ore. Also, cases are not unfrequent, where a vein
producing one metal, on traversing a different stratum,
produces another metal, copper replacing tin, or tin copper,
and so in other combinations.




CHAPTER XIII.                 205
All these facts agree with the view that the different
aetals are formed, under strong pressure, deep below the
urface of the earth; but that their state, as found in the
reins, depends on the mechanical conditions under which
he veins are formed, and on the character of the stratum or,ountry through which they successively pass, while ex)anding and cooling in their escape from the original
)ressure.
The atomic numbers of silver and lead are 108 and
[03'5, which differ little from each other. Lead is far
nore plentiful, but a small proportion of silver is found to:e contained in the most common lead ores. Platinum
lnd irldium have almost exactly the same atomic number,
mnd are associated usually in the ore.  Copper veins
lhange into tin, or tin into copper, while the presence of
Lron is held to be an unfavourable sign, in searching for
these metals. These facts, and many others of the same
kind, are comparatively easy to understand, if the metals
are not simple, but composite, and their formation depends
on special circumstances of heat, pressure, and electric
influence, so that a change in one of them may alter the
nature of the metallic product.
148.  Czhemical -Relations of Geological Eras.
A striking fact, in geology, is the special development
of some chemical element or compound at particular eras of
the earth's history.
To take a single example: the great development of
carboniferous deposits at a certain period is generally supposed to imply simply an immense vegetation, receiving
carbon from an atmosphere charged with carbonic gas,
When, however, we consider the thickness of these seams
of coal, and the vast surfaces over which they extend,




206            ON MATTER AND ETHER.
it is difficult to conceive of an atmosphere which, could
furnish the supply required. On the other hand, since
carbon, from the lightness of its atom, and the gaseous
nature of its compounds with hydrogen, oxygen, and nitrogen, forms a transition between the earthy and metallic
bases and the gaseous elements, it is natural to conceive
that there must be some midway stage of geological
change, favourable to its development, when vegetable
life would be most amply supplied with it, and be the
means of laying it up in store for after ages of mankind.
149. The saltness of the ocean is another leading
fact, of which no explanation is offered on the principles
of our actual chemistry. It has also been shewn that the
saltness increases at greater depths. But if the atom of
sodium, as has been shewn to be probable, bears a simple
relation to the atoms of water, in that form which they
would assume under strong pressure, and chlorine or
muriatic acid has a relation to it of the opposite kind, so
that one may result from water compressed axially, and
the other fiom water expanded radially, under the opposite influence of intense pressure, we shall have a simple key to a phenomenon so fundamental in the scheme
of nature, and which has baffled ordinary methods of
explanation.
150. Another striking fact, of which no satisfactory
account has yet been given, is the constitution of the
atmosphere. It consists, by volume, of four parts of nitrogen and one of oxygen; or, if 8 and 14 are taken for the
atomic weights, of two atoms of nitrogen and one of oxygen. This proportion is maintained wherever the atmosphere is analyzed, in spite of the perpetual change to
which it is exposed from the action of animal and vege



CHAPTER XIII.                 207
table life. On the other hand, it is a mixture, and not a
chemical compound, though this exact chemical relation
between its two elements is still maintained.
If, however, we accept the first principle of the present
theory, that all the elements are convertible under proper
conditions of pressure or electricity, a relation of singular
simplicity reveals itself. Two volumes of hydrogen, and
one of oxygen, united by the electric spark, produce two
volumes of aqueous vapour, and thus, from synthesis and
analysis at the surface of the earth, water is viewed as the
compound of these two gases in this proportion. Tried,
however, by the test of volumes, it is one atom of hydrogen, and half an atom of oxygen gas, which form an atom
of water. But four atoms of nitrogen gas, and one of
osygenl gas, the ratio in the atmosphere, give 72 for their
atomic number, which is precisely the atomic weight of
eight atoms of water. Now  as aqueous vapour mounts
higher in the air, it must plainly tend to a more gaseous
condition. And hence, as in the case of forced vibrations,
or synchronous movements in general, the atoms of nitrogen and oxygen must have a certain tendency to assimilate this vapour to themselves; while the relation of the
numbers is such as to ensure that its decomposition into
these two gases, if capable of being effected at all, will
be only in this proportion. The case will be similar to
the relation between the periodic times of satellites, where
a near approach, by a constant cause, is turned into an
exact proportion.  Supposing an approach to this ratio
at first, and a power, in the highest region of the air,
to resolve aqueous vapour into these two gases, a cause
perpetually at work would tend to secure finally this exact
proportion throughout the whole.




208            ON MATTER AND ETHER.
Such a tendency of the oxygen and nitrogen of the
atmosphere to transform  aqueous vapour, when extremely
rarefied, must result at once from the present theory. For
the atoms of water, whether arranged in three triplets, or
in two fours and a unit, must be changed by the absorption of latent heat, in ascending, till they take the form of
a single cycle of nine. But when this cycle is expanded,
so that the cohesion of its nearest units is weakened, its
rotation will be out of harmony with those of the oxygen and nitrogen in their nearest appulse. If four pairs of
them, by the rotatory rhythm of the nitrogen atoms, are
turned into nitrogen, the four quaternions separated from
them will equally combine to form an atom of oxygen.
The change, if it occurs at all, must take place at the upper
limit of the presence of aqueous vapour, and consequently
above the region of the highest clouds, where the exciting
power of the solar rays must be the greatest, and the
cohesion of the cycles is reduced much below its amount at
the surface of the earth. It is therefore no objection to the
view, that water cannot be separated into these two gases
under the conditions which actually obtain at the surface of
the earth.
151. The origin and composition of meteoric stones
has given rise to much speculation.  The general opinion,
at present, is that they are wholly cosmical, or extra-terrestrial, especially since the occurrence of shooting-stars is,
to a great extent, periodic, and occurs when the earth is in
one or two special parts of her annual orbit. But two
serious difficulties still remain. First, it seems clear that,
in many instances, meteoric stones or thunderbolts, are
directly the result of thunderstorms, or violent electric
disturbance within the atmosphere, especially in tropical




CHAPTER XII.                 209
countries. And, next, it seems strange and unaccountable
that floating, matter in planetary space should consist
mainly of two or three metals, to the exclusion of others,
and these metals the same which ale distinctively magnetic.
If our present elements are viewed as ultimate, independent
forms of matter, no key is supplied to either of these phenomena.!Now let us compare the atomic weights of these meteoric and magnetic metals with those of the atmospheric
gases, and a relation of singular simplicity discloses itself.
Nitrogen is the chief constituent of the atmosphere, iron
the most magnetic metal, and the most abundant constituent of meteoric stones, some of which are indeed
masses of meteoric iron. The atomic weight of nitrogen
is 14, of iron 28; or two atoms of nitrogen, by weight, will
exactly form one atom of iron. Again, the atoms of nickel
cobalt are each reckoned at 29k. But as two atoms of
nitrogen would be 28, so an atom of nitrogen and one of
oxygen woulcl make 30, almost exactly the atomic weight
of each of these metals. The magnetic character, also,
of these elements in meteoric stones is a clear sign that
they result, in some way, from a powerful electric influence.
Again, this view of the formation of meteoric iron, and
the kindred metals, carries out a plain analogy. In common thunder showers, the electric action is moderate, and
its effect is to condense aqueous vapour into large or small
drops of rain. In violent thunder storms, the electric force
is greater, and the vapour is not only condensed into
water, but compacted into solid hail stones, sometimes
of uncommon size. In thunder storms still more violent,
or in disturbances caused by foreign matter encountering the
earth's annual motion, it is quite consistent to believe that
14




210            ON TMATTER AND ETHER.
the electric action would be more powerful still, and might
condense the atoms of the air itself, crushing out the ether
which separates the nearest, and converting them, by pairs,
into the atoms of solid and magnetic metals.
On the view here proposed, the nature of such a transformation of nitrogen into iron may be easily conceived.
Intense ethereal pressure, from without, will first bring two
cycles of fourteen axially together.  The same pressure,
acting on their circumference, will force them to resolve
themselves each into two cycles of seven; and the same
disturbance, or ejection of the central ether, will force one
of the seven units in each cycle to pass inward, and occupy the centre. The resistance to further compression
will then be completed, while intense heat will of course
be developed by this immense condensation, and the closer
approach of the component units of matter.
152. "' The atmospheric hypothesis," Dr Lardner remarks, "is subject to objections so unanswerable, that it
may be considered as altogether set aside. In order to
suppose it probable that aerolites can be formed in the
atmosphere, we must shew that their constituent elements
can exist there. But the most rigorous analysis has never
detected in the air any of the constituents of meteoric
stones...The actual velocities with which they are known
to strike the earth could never be acquired under the mere
agency of terrestrial gravity. If the velocity of the meteorites be incompatible with this theory, their direction is
still more, and their obliquity could never be produced by
any atmospheric current" (Jltus. I. p. 138).
These objections, it is plain, are wholly inapplicable to
the view here proposed.  The materials of the meteoric
metals will be present abundantly, being the atmospheric




CHAPTER XIII.                 211
gases themselves. The same intense electric energy which
is required for their formation will be clearly adequate to
impress upon them an oblique direction, and an immense
velocity. The explanation includes equally the phenomena
which indicate a cosmical, and those which point to a terrestrial origin.  In the former case, the uncondensed matter of outer space, encountering the earth in its orbit, may
be condensed, and condense the air, in passing through its
highest and most electric portions; while, in other cases,
violent electric energy within the atmosphere itself may
have the like effect without foreign collision.  The periodical shooting stars will belong to one class, and the
meteors of thunder storms, or those which are proved to be
of moderate height, and in some instances to move upward,
will be of the other.' IIn general, the trains of shooting stars have the same
hollow, cylindrical appearance as the tails of comets, their
inner part appearing to be void of luminous matter, and a
further resemblance to comets is seen in the curved form
which they sometimes assume. Beccaria and Vassali considered them to be lines of electric sparks, an hypothesis
which has been abandoned. Lavoisier, Volta, and others,
supposed that hydrogen, accumulated by its lightness in
the higher regions of the atmosphere, was inflamed.  But
the law of gases which gives them a tendency to mingle,
notwithstanding' their specific gravity, sets aside this hypothesis...Poisson affirmed the probability of an atmosphere
of electricity surrounding the earth, and higher than the
atmosphere of air, and that the meteorite rushing through
this atmosphere would decompose this electric fluid, like
the friction of a machine."
All these divergent suggestions are harmonized and




212            ON MATTER AND ETHER.
reconciled by the results of the present theory.  The outmost strata of the atmosphere, where chemical structure
and gaseous repulsion cease, must be composed of igneous
matter, or hydrogen gas, saturated with ether by the remoteness of its atoms from each other, and their diminished
motion. There will thus be an atmosphere of positive
electricity, with a shell of hydrogen for the material vehicle on which it depends. The phenomena of shooting
stars will depend on electric disturbance, or the swift passage of foreign matter, in this highest region, where the
exceeding rarity of the matter makes the results to be electrical or luminous alone.  The resemblance of the trains to
the tails of comets will result at once firom the sameness of
the conditions. But when the electric disturbance, or the
rapid transit, takes place in lower regions, where the gases
of the atmosphere subsist unchanged, the effect of the
intense compression may be the' formation of meteoric iron
and the other kindred metals, joined also, in some cases,
with the electro-negative elements.
"'The meteorites which fell at Agram in India, those
which were found at Sisim, in the Jeniseisk government,
and those brought by Humboldt from Mexico, contained
as much as 96 per cent. of very malleable iron."  Can we
suppose it in the least probable, that the floating matter of
the planetary spaces, which our earth encounters in its
annual orbit, consists of this one magnetic metal, ready
formed, in so large a proportion?
153.  Connexion betzween the Sun and Terrestrial Miagnetism.
It has been ascertained, within the last few years, that
there is an intimate relation between the solar light and
the oscillations or variations of the earth's magnetism.




CHAPTER XIII.                 213
The observations of Schwabe seem  to prove that the
maximum and minimum of the solar spots, in a decennial
period, correspond with a maximum  and minimum  of
magnetic power on the surface of the earth.
On the origin of the period itself it would perhaps
be premature to offer any conjecture. But the present
theory implies at once an intimate relation between the
solar light and terrestrial magnetism.  For magnetism,
on this view, is only a special result, in bodies of a peculiar atomic constitution, of the general fact of polarity,
arising from  moments of rotation, and the tendency of
similar motions, through the intense elasticity of free ether,
to generate each other, and of dissimilar motions to interfere with each other. Hence it seems to follow, as a
natural consequence, not only that the magnetic power of
the earth depends upon, and is derived from, its own
rotation on its axis; but that the same cause, in the greater
mass and with the swifter equatorial motion of the sun,
must produce a magnetism far more intense, and capable
probably of a sensible effect, even at his immense distance.
And since the vehicle of its transmission must be the
luminous atmosphere, any variation, such as that of the
solar spots, implying a periodic change in that atmosphere,
may be expected, on the principles of the theory, to have
some effect, and probably a sensible effect, on the variations of terrestrial magnetic power.
154. Source of the Solar Liqht and Heat.
Another subject, which has given birth of late to some
ingenious speculation, is the means by which the supply of
the sun's light and heat is sustained. The latest hypothesis, recommended rather by the difficulties which encompass




214            ON MATTER AND ETHIER.
every other, than by its own elegance, is that the surface
of the sun is hammered into a white heat by the continual impact of revolving bodies, or extra-solar planetoids,
since heat and mechanical force are strictly convertible.
Combustion, it is thought, could not sustain the immense
efflux of light and heat without causing a sensible waste
of the sun's body; so that the impact hypothesis, however
strange and unpoetical, is conceived to be alone capable of
meeting the conditions of the physical problem.
The present theory suggests a very different explanation, which accords far better with all the analogies of
nature. The mechanical energy which the sun exerts,
in the light and heat which flow from it to all the planets,
must plainly, on this view of matter and ether, be a direct
result from the rotation of the immense central mass.  It
cannot, then, be the same in all directions. By virtue of
its revolution the sun must form a vast magnet, and a
special repulsion, propagated throug'h the ether in the
plane of the equator, be compensated by a special attraction in the line of the poles. The mechanical energies
which are thrown out continually in light and heat cannot
be wasted, or lose themselves in space, and must return, by
ac coslical circuit, to their natural home. The ethereal
force will thus diffuse itself in swift undulations to the
verge of the solar system; and travelling at right angles,
when this impulse ceases or grows feeble, will return to
the centre in the line of the solar axis.
This view seems to meet with partial, indirect confirmation, in a singular astronomical fact.  The orbits of the
planets and their satellites, in general, lie near to the plane
of the ecliptic. But the satellites of Uranus, the outmost




CHAPTER XTII.                  215
planet except Neptune, are a remarkable exception.  They
are inclined at an angle of 78~0, and since their motion is
lretrograde, 1020 may rather be viewed as their true inclination. All recent discovery also tends to prove the existence of strong directive forces, whatever be their mechanical cause, on which electric currents and magnetic action
depend.  We may infer that the directive force, at the
distance of Uranus, is no longer in the ecliptic plane,
but more nearly at right angles.  We should thus have
reached, or nearly, the middle stage in a grand cosmical
circuit, where the ethereal energy, emanating from the sun
as a centrifugal force in the plane of the equator, begins to'
travel at right angles, that it may return at length, in the
line of the axis, to the centre again. It is even conceivable that in this way magnetic relations of polar attraction
and repulsion may be generated between distant solar or
sidereal systems on the largest scale.
There are many relations among the known facts of
science which acquire a new significance, when compared
with the present theory of the constitution of matter, and
may perhaps open new fields of inquiry or future discovery.
But in the present stage of its development, it may be
wiser to abstain from further suggestions, which must partake largely of a tentative and conjectural character.  The
main principle of the theory, the inductive basis on which
it rests, and the simple solution it supplies to all those
classes of phenomena which form  the  great branches
of physical science, have now been unfolded at sufficient
length for a first Essay. It is now committed to the
candid reflection of men of science, with the strong confidence, that it either supplies the true and sufficient key to




216              ON MATTER AND ETHER.
the remaining secrets of inorganic nature, or at least will
assist other and more skilful labourers in its discovery,
whenever it shall please the Supreme Architect to make
a second and fuller revelation of those laws, which preside
over all the countless phenomena of change in the outward world.
CA,4MBRIDGE; PRINTED BY C, J. CLAY, 5M.A. AT THE UNIV~ERSITY PRESS.




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10




RELIGIO CHEMICI.
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