Various - Scientific American Supplement, No. 312, December 24, 1881

V >> Various >> Scientific American Supplement, No. 312, December 24, 1881

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ELECTRICITY; WHAT IT IS, AND WHAT MAY BE EXPECTED OF IT.[1]

[Footnote 1: A paper read before the Engineers' Society of
Western Pennsylvania, Nov. 15, 1881.]

By JACOB REESE

In the consideration of this subject it is not my purpose to review
the steps of discovery and development of electrical phenomena, but
the object of this paper is an effort to explain what electricity is;
and having done this, to deduce some reasonable conclusions as to what
may be expected of it. And while I am profoundly sensible of the
importance of the subject, and the difficulties attending its
consideration, still with humble boldness I present this paper and ask
for it a serious and careful consideration, hoping that the discussion
and investigation resulting therefrom may add to our knowledge of
physical science.

It is now a well established fact that matter, _per se_, is inert, and
that its energy is derived from the physical forces; therefore all
chemical and physical phenomena observed in the universe are caused by
and due to the operations of the physical forces, and matter, of
whatever state or condition it may be in, is but the vehicle through
or by which the physical forces operate to produce the phenomena.

There are but two physical forces, i.e., the force of attraction and
the force of caloric. The force of attraction is inherent in the
matter, and tends to draw the particles together and hold them in a
state of rest. The force of caloric accompanies the matter and tends
to push the particles outward into a state of activity.

The force of attraction being inherent, it abides in the matter
continuously and can neither be increased nor diminished; it, however,
is present in different elementary bodies in different degrees, and in
compound bodies relative to the elements of which they are composed.

The force of caloric is mobile, and is capable of moving from one
portion of matter to another; yet under certain conditions a portion
of caloric is occluded in the matter by the force of attraction. That
portion of caloric which is occluded (known by the misnomer, latent
heat) I shall call _static caloric_, and that portion which is in
motion, _dynamic caloric_.

The force of attraction, as I have said, tends to draw the particles
of matter together and hold them in a state of rest; but as this force
is inherent, the degree of power thus exerted is in an inverse ratio
to the distance of the particles from each other. The effective force
so exerted is always balanced by an equivalent amount of the force of
caloric, and that modicum of caloric so engaged in balancing the
effective force of attraction is static, because occluded in that
work.

In solid or fluid bodies, where the molecules are held in a local or
near relation to each other, the amount of static caloric will be in
direct proportion to the effective force of attraction, but in gaseous
bodies the static caloric is in an inverse ratio to the effective
force of attraction; hence the amount of static caloric present in
solid and fluid bodies will be greatest when the molecules are nearest
each other, and greatest in gaseous bodies when the molecules are
furthest apart.

Caloric, whether static or dynamic, is not phenomenal; therefore the
phenomena of light, temperature, incandescence, luminosity, heat,
cold, and motion, as well as all other phenomena, are due to the
movement of matter caused by the physical forces. Thus we find that
_temperature is a phenomenal measure of molecular velocity_, as we
consider weight to be the measure of matter.

An increase of temperature denotes an increased molecular velocity,
and this in solid and liquid bodies unlocks a portion of the static
caloric and converts it into dynamic caloric, while an increased
temperature of gases occludes additional caloric, thus converting
dynamic into static caloric; and a reduction of molecular activity
reverses this action. From this we see that a change of temperature
either converts static to dynamic or dynamic to static caloric.

Thus we find that the amount of static caloric which a body possesses
is in direct relation to its temperature, but, as I have already
explained, temperature is a phenomenal indication of molecular
velocity, and as increased velocity separates the molecules to a
greater distance, which reduces the effective force of attraction and
unlocks a portion of caloric, it will be seen that the separation of
the molecules from any other cause will have the same effect. I desire
now to explain a second method by which the molecules are separated
and static caloric is changed to dynamic caloric.

It is not definitely known how much static caloric is occluded in
either of the elementary bodies, but it is believed that hydrogen
possesses the greatest amount and oxygen the least. Now if we take a
molecule of hydrogen containing two atoms, and under proper conditions
interpose these atoms between 16 atoms of oxygen (one molecule), the
phenomenon of combustion is exhibited, and a molecule of water is
formed containing 18 atoms; and if one pound of hydrogen is thus
consumed, the atoms of hydrogen are separated from each other to such
a distance by the interposing atoms of oxygen as to unlock 34,662
units C. of static, and convert it into dynamic caloric. And if we
thus bring a molecule of carbon containing 12 atoms in contact with a
molecule of oxygen of 16 atoms, combustion ensues and a molecule of
carbonic oxide of 28 atoms is formed, and if we then present another
molecule of oxygen, combustion again takes place, and a molecule of
carbonic acid, containing 44 atoms, is produced. Now, in the
combustion of one pound of carbon in this manner, when the carbon is
converted into carbonic oxide (CO), 2,473 units C. of static is
converted into dynamic caloric; and when this CO is converted into
carbonic acid (CO_{2}) 5,607 additional units C. are unlocked. Thus by
the combustion of one pound of carbon to CO_{2}, 8,080 units C. of
static caloric are changed to dynamic caloric.

When caloric is thus unlocked from its occlusion it escapes with great
velocity until an equilibrium is attained, and in doing so it pushes
the particles of matter out of its path. In solid bodies this produces
such a high degree of molecular movement as to exhibit the phenomena
of incandescence and luminosity, and in liquids increased mobility,
while in gases the molecular activity may be so great as to produce
the phenomena of sound and light; and the more rapidly combustion
takes place the greater will be the volume and velocity of dynamic
caloric escaping therefrom; consequently with a slow combustion, the
phenomena produced by dynamic caloric will be different from those
exhibited at a high degree.

Combustion, as I have before shown, is merely the oxidation of the
material; nothing is _consumed_ nor annihilated, and, the phenomena
vary with the velocity of oxidation. Now, if we take one pound of zinc
and place it in the acid cell of an electric battery, the oxygen of
the acid attacks the zinc and oxide of zinc is formed. In this
operation the Zn molecule containing 65 atoms is united with one
molecule of oxygen of 16 atoms, forming a molecule of oxide of zinc
(ZnO) of 81 atoms; and owing to the comparatively small number of
oxygen atoms interposed between the 65 atoms of zinc, only 1,301 units
C. of static caloric are unlocked to the pound of zinc, and the
velocity of oxidation is so low, and the insulation of the vessel so
perfect, that the dynamic caloric is caused to flow outward through
the copper wire.

ELECTRICITY.--What is it? Why, it is dynamic caloric. Now let
us take this oxide of zinc (ZnO) and place it with charcoal in a
reducing apparatus which stands on an insulated table; the apparatus
is then heated, the carbon vaporizes, and this vapor of carbon (C)
robs the oxide of zinc (ZnO) of its oxygen, leaving metallic zinc (Zn)
and carbonic oxide (CO). Now, for every pound of zinc so formed 1,301
units C. of static caloric are transferred from the charcoal to the
zinc and occluded in it. Hence we find that the 1,301 units C. of
caloric which we took out of the zinc, and which we call electricity,
is nothing else but the 1,301 units of static caloric which was
contained in the charcoal and from it set free by oxidation and
transferred to the zinc in the smelting process. Let us follow this
matter a little further. Charcoal is made by burning wood under such
conditions as eliminate the water and hydrogen and leave the carbon as
a residuum which we call charcoal. Thus we find that the caloric
contained in the charcoal, transferred from the charcoal to the zinc,
and from it developed into what we call electricity, was previously
embodied in the wood; and if we study the laws of vegetation, we find
that the atmosphere being charged with carbonic acid (CO_{2}), the
leaves of plants, shrubs, and trees, breathing, take in the CO_{2}, the
sun rays decompose the CO_{2}, set free the oxygen, and supply the
necessary amount of caloric for the condensed state of the carbon.
Thus we find that the force which we term electricity, developed from
the oxidation of zinc, or any other matter, by oxidation, primarily
comes from the sun rays.

Coal is generally supposed to be of vegetable origin, and the caloric
occluded in it is derived from the same source as that embodied in
charcoal. Now when we burn coal under a steam boiler, the carbon and
hydrogen are oxidized, and the static caloric set free. A portion of
this caloric passes through the shell or tubes of the boilers, and
increases the molecular velocity of the water; increased activity of
the molecules tends to separate them to a greater distance from each
other. When the molecular velocity of the water acquires the degree
indicated by a temperature of 212 degrees F., the water passes from
the fluid to the gaseous state, and in doing so expands to 1,696 times
its bulk. Now if the steam so developed be confined under a pressure
of 105 pounds to the square inch, the water will not vaporize until a
molecular velocity is attained indicated by a temperature of 312 deg. F.
(Spons' "Engineering," D2, page 418), and then the expansion is only
253 times its bulk. By using this steam, in a steam engine, the
caloric in the steam tends to push the molecules of which it is
composed into an ultimate expansion of 1,696 times the bulk of the
water from which it was generated, and this force acts upon the piston
and does the work. Thus we see that the steam engine is driven by the
same force which produces the phenomena accredited to electricity.

I have already shown that in what we term combustion not a particle of
the ponderable matter is annihilated. Combustion is but a phenomenon
resulting from a rearrangement of the particles, and so it is with the
imponderable physical force caloric; it is not consumed when light and
heat are produced, nor converted into power, as we are sometimes told.
But whatever the phenomena produced, the aggregate amount of static
and dynamic caloric is always and ever the same.

If we consider the Ritter-Plant-Faure-Battery, which is mentioned as
storing electricity, we find that the phenomena exhibited by the use
of this apparatus are produced by the same factor. The battery is
composed of two sheets of lead, which are covered with a layer of
minium (Pb3O4). The sheets are laid one upon the other with an
intervening layer of felt. The pack is then rolled up in a spiral form
and placed in a vessel containing acidulated water. One of the plates
is connected with the positive, and the other plate with the negative
pole of a battery or generator.

When the current of electricity enters the battery, the Pb3O4 on the
positive plate is reduced to Pb, and the oxygen so set free attacks
the Pb3O4 on the negative plate, and oxidizes it to PbO2. In this
chemical action, caloric is occluded in the Pb and unlocked in the
PbO2, but a much greater amount of caloric is locked up than is
unlocked, although the amount of oxygen used in both cases is
precisely the same, which has been fully explained in the oxidation of
carbon.

Now after the battery has been thus charged and the wires disengaged,
the chemical action ceases for want of the reducing agent (_dynamic
caloric_), and the apparatus may be held at rest, or transported to
any distance required. When it is desired to utilize the force thus
stored, the poles are changed by grounding the positive wire, and
attaching the other to the conduit through which the electricity is to
flow. The chemical action is thus reversed, and the PbO2 is reduced to
Pb3O4, the oxygen thus set free attacks the Pb on the other plate,
oxidizing it to Pb3O4, thus unlocking all the caloric which was
occluded by the first action. In a battery of this kind weighing 75
pounds, we are informed by Sir William Thomson, that one million foot
pounds of force may be stored, and again set free for use.

Thus we find that the principle upon which the Faure battery is formed
is not new, and the prime factor producing the phenomena is the same
as has been shown to have caused all other phenomena referred to, and
indeed the principle is the same as now employed by the author in the
basic dephosphorizing process, i.e., caloric is occluded in
phosphorus by smelting in a blast furnace, and unlocked in the
converter, for the purpose of securing the fluidity of the metal
during treatment. The difference being, that one is done by
non-luminous, while the other is by luminous combustion.

If we consider the phenomenon of light, we find that it is due to the
same force. As before stated, when we oxidize carbon, or hydrogen, as
in the rapid combustion of wood, oil, or coal, the escaping caloric
flies off with such great speed as to cause the molecules in the
circumambient medium to assume a velocity which exhibits luminosity.
Thus the light produced by burning candles, oil, gas, wood, and coal,
is caused by the same prime factor, dynamic caloric.

The force of caloric is imponderable and invisible, and is only known
by its effects. We do know that it is occluded in metals and other
material, because we can unlock it and set it free, or we can transfer
it from one body to another, and by measuring its effects, we can
determine its quantity. We know that it prefers to travel over one
vehicle more than another, and by this knowledge we are able to
insulate it, and thus conduct it in any direction desired. The
materials through which it passes with the greatest freedom are called
conductors, and the materials which most retard its passage,
non-conductors; but these terms must be taken in a comparative sense
only, as in fact there are no absolute non-conductors of dynamic
caloric, or of what we call electricity.

The dynamo-electric generator simply draws the dynamic caloric from
the air or earth, or both, and confines it in an insulated path. Now
if that path be a No. 10 wire, the conduit may be sufficient to permit
the caloric to pass without increasing the molecular velocity of the
metal to an appreciable degree, but if we cut the No. 10 wire and
insert a piece of No. 40 platinum wire in the path, the amount of
caloric flowing through the No. 10 wire cannot pass through the No. 40
wire, and the resistance so caused increases the molecular velocity of
the No. 40 wire to such degree as to exhibit the phenomenon of
incandescence, and this is the incandescent electric light. And if we
consider the carbon light, we find that the current of caloric, in
passing from one pencil to the other, produces a molecular velocity of
luminosity in the adjoining atmosphere, and in addition a portion of
the carbon is consumed, which sets free an additional amount of
caloric, at a very high velocity, hence the intensity of the carbon
electric light is largely due to the dynamic caloric unlocked from the
pencils, and thus we find that the electric light produced by either
method is due to the action of dynamic caloric.

Taking this theory based upon physical science, and the facts which we
know pertaining to electricity, I conceive that caloric exists in two
conditions. _Static caloric_ is what we call _latent heat_, and
_dynamic caloric_ is what we call _electricity_. Therefore what may we
expect of it (electricity) is merely a matter of economy in the
development and utilization of dynamic caloric; in other words, can we
unlock static caloric by non-luminous combustion, and thus develop
_dynamic caloric as a first power_ more economically per foot pound
than we now do or can hereafter do by luminous combustion? Second, can
we utilize water and wind for the production of _dynamic caloric as a
first power_? Third, can we utilize the differential tension of
dynamic caloric in the earth and the atmosphere as _a first power_?
Fourth, will it pay to use luminous combustion as a first power to
generate dynamic caloric as _a second power_?

WHAT MAY WE EXPECT OF IT.

Let us take the steam engine, and see what we are now doing by
luminous combustion. Good Pittsburg coal contains 87 per cent. of
carbon, 5 per cent. of hydrogen, 2 per cent. of oxygen and 6 per cent.
of ash; we therefore have in one pound of such coal:

8,080 x 9 14,544 x 87
--------- = ----------- = 12,653 units in carbon.
5 100

34,662 x 9 62,391 x 5 3,119 units in hydrogen.
---------- = ---------- = ------
5 100 15,772 units in coal.

15,772 x 772[2] = 12,175,984 foot pounds of energy is occluded in the
static caloric contained in one pound of such coal.

[Footnote 2: Dr. Joule--foot pounds in one unit.]

A horse-power is estimated as capable of raising 33,000 pounds one
foot high per minute, and for this reason it is termed 33,000 foot
pounds per minute. So we have 33,000 x 60 = 1,980,000 foot pounds per
hour, as a horse-power.

The best class of _compound condensing_ engines,[3] with all the
modern improvements, require 1.828 pounds of coal per 1 h.p. per hour.
Thus we have--

12,175,984 x 1.828 .................22,257,699
Foot pounds in one h.p. .............1,980,000
----------
Foot pounds lost per h.p. ..........20,277,699

Per cent utilized per h.p. ..............8.94
Per cent lost per h.p. .................91.06
------
100.00

[Footnote 3: "American Engineer," Vol. II., No. 10, page 182.]

In the ordinary practice of stationary non-condensing engines, from
three to four pounds of coal are required per horse-power per hour.
Now, taking the best of this class at 3 pounds, we have--

12,175,984 x 3 = 36,527,952
One h.p. 1,980,000
----------
Loss per h.p. 34,547,952

Per cent utilized per h.p. 5.42
Per cent lost per h.p. 94.58
------
100.00

From these facts it may be assumed that after making due allowance for
variable qualities of the coal, the steam engine process, as at
present practiced, will not utilize more than from 5 to 10 per cent.
of the energy contained in the fuel used. It will thus be seen that
the process of converting static to dynamic caloric by luminous
combustion, by means of the steam engine, is an exceedingly wasteful
and costly method, and leaves much room for economy.

Taking an ordinary grade of petroleum as consisting of 13 per cent.
hydrogen, 78 carbon, 6 oxygen, 3 nitrogen and ash, we have as its
energy in foot pounds per pound of oil--

62,391 x 13 }
----------- = 8,110 H. }
100 }
} 19,454 units.
14,544 x 78 }
----------- = 11,344 C. }
100 }

19,454 x 772 = 15,018,488 foot pounds. Thus, while our best coal
contains twelve million, the petroleum contains fifteen million foot
pounds of occluded energy in each pound, which is equal to 118,000,000
foot pounds, or 60 horse power for one hour, from one gallon of such
oil.

At present electricity is generated by two methods, and both of these
are _second powers_. Metals are smelted by luminous combustion as a
first power, and then oxidized by non-luminous combustion as a _second
power_, and coal is consumed by luminous combustion, by which steam is
generated as a first power, to drive a dynamo-generator whereby
electricity is obtained as a _second power_. Now, of the two methods,
the latter is much the cheaper, and as I have shown that the best
compound condensing engines only utilize 8.94, and a fair average
single cylinder condensing engine only utilizes 5.42 per cent. of the
energy of the fuel consumed, and as at the best not over 70 per cent.
of the foot pounds obtained from the engine can be utilized as
electricity, from which we must deduct loss by friction, etc., it will
be readily seen that not more than 5 per cent. of the energy of the
fuel can be developed by the dynamo-generator as electricity by the
present method.

The great want of the present age is a process by which the static
caloric of carbon or a hydrocarbon maybe set free by non-luminous
combustion; or, in other words, a process by which coal or oil may be
oxidized at a low degree, within an insulated vessel; if this can be
accomplished (and I can see no reason why we should not look for such
invention), we would be able to produce from twelve to fifteen million
foot pounds of energy (electricity) from one pound of petroleum, or
from ten to twelve million foot pounds from one pound of good coal,
which would be a saving of from 90 to 95 per cent. of present cost,
and leave the steam engine for historical remembrance.

Electricity may be generated by water or wind power to great
advantage, and conveyed to a distance for motive power. The
practicability of generating electricity at Niagara by which to propel
trains to New York and return may be considered almost settled; and I
conceive a second invention of importance which is now needed is an
apparatus by which the rising and falling tides may be utilized for
driving dynamo machines, by which electricity may be generated for
lighting the coast cities, and it is not unreasonable to expect that
such an apparatus will soon be provided; and in such an event gas
companies would suffer.

It is a well known fact among electricians that the volume and tension
of electricity vary both in the earth and in the atmosphere at
different sections of the earth's surface, and I conceive that we may
yet find means of utilizing this differential tension of electricity;
indeed, it is reported that during a recent storm the wires of an
ocean cable were grounded at both ends and a sufficient current for
all practical purpose flowed from the European to the American
continent, with all batteries removed, showing that the tension was so
much greater in Europe as to cause the electricity to flow through the
copper cable to this side in preference to passing through the earth
or the sea. It is also said that during an east-going storm it was
found impossible to work the telegraph lines between New York and
Buffalo, but on taking off the batteries at both ends and looping the
ends of the wire in the air, that a constant current of electricity
passed from Buffalo to New York, and the line was kept in constant use
in that direction without any battery connection until the storm
abated. Now, how far or to what advantage we may be able to utilize
this differential tension of electricity in the earth and the air, we
cannot now say; but I think that we may justly look for valuable
developments in this direction.

If, as I verily believe, a process will soon be discovered by which
dynamic caloric can be produced by the oxidation of petroleum with
non-luminous combustion in an insulated chamber, as we now oxidize
zinc, electricity will then be obtained from so small a weight, and at
such a low cost, as to insure aerial navigation beyond a doubt. Not
with balloons and their cumbrous inflations, but with machines capable
of carrying the load, and traveling by displacement of the air at high
velocities. Therefore we may expect that aerial navigation will be
developed in the near future to be one of the greatest enterprises of
the world.

And lastly, will it pay to use luminous combustion as a first power
for generating dynamic caloric for use as a second power, as is now
practiced?

At the University of Pennsylvania, in Philadelphia, gas is consumed in
an Otto gas engine, which drives a Gramme generator; and the lecture
room is lighted with electricity, and I am informed that the light is
both better _and cheaper_ than when they used the gas in the ordinary
gas burners. Hence we may expect to see gas consumed to advantage for
producing electric lights.

Considering the difficulties of transmitting steam power to a
considerable distance, and the comparative great cost of running small
engines, it is more than likely that electricity as at present
generated will be found to be economical for driving small motors.

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