THE WONDER WORLD
TO BE CREATED BY ELECTRICITY
by Nikola Tesla
Manufacturer's Record, September 9, 1915
Whoever
wishes to get a true appreciation of the greatness of our age should
study the history of electrical development. There he will find a
story more wonderful than any tale from Arabian Nights. It begins long
before the Christian era when Thales, Theophrastus and Pliny tell of
the magic properties of electron—the precious substance we call
amber—that came from the pure tears of the Heliades, sisters of
Phaeton, the unfortunate youth who attempted to run the blazing
chariot of Phoebus and nearly burned up the earth. It was but natural
for the vivid imagination of the Greeks to ascribe the mysterious
manifestations to a hyperphysical cause, to endow the amber with life
and with a soul.
Whether this was actual belief or merely poetic
interpretation is still a question. When at this very day many of the
most enlightened people think that the pearl is alive, that it grows
more lustrous and beautiful in the warm contact of the human body. So
too, it is the opinion of men of science that a crystal is a living
being and this view is being extended to embrace the entire physical
universe since Prof. Jagadis Chunder Bose has demonstrated, in a
series of remarkable experiments, that inanimate matter responds to
stimuli as plant fiber and animal tissue.
The superstitious belief of the ancients, if it
existed at all, can therefore not be taken as a reliable proof of
their ignorance, but just how much they knew about electricity can
only be conjectured. A curious fact is that the ray or torpedo fish,
was used by them in electro-therapy. Some old coins show twin stars,
or sparks, such as might be produced by a galvanic battery. The
records, though scanty, are of a nature to fill us with conviction
that a few initiated, at least, had a deeper knowledge of
amber-phenomena. To mention one, Moses was undoubtedly a practical and
skillful electrician far in advance of his time. The Bible describes
precisely and minutely arrangements constituting a machine in which
electricity was generated by friction of air against silk curtains and
stored in a box constructed like a condenser. It is very plausible to
assume that the sons of Aaron were killed by a high tension discharge
and that the vestal fires of the Romans were electrical. The belt
drive must have been known to engineers of that epoch and it is
difficult to see how the abundant evolution of static electricity
could have escaped their notice. Under favorable atmospheric
conditions a belt may be transformed into a dynamic generator capable
of producing many striking actions. I have lighted incandescent lamps,
operated motors and performed numerous other equally interesting
experiments with electricity drawn from belts and stored in tin cans.
That many facts in regard to the subtle force were
known to the philosophers of old can be safely concluded, the wonder
is, why two thousand years elapsed before Gilbert in 1600 published
his famous work, the first scientific treatise on electricity and
magnetism. To an extent this long period of unproductiveness can be
explained. Learning was the privilege of a few and all information was
jealously guarded. Communication was difficult and slow and a mutual
understanding between widely separated investigators hard to reach.
Then again, men of those times had no thought of the practical, they
lived and fought for abstract principles, creeds, traditions and
ideals. Humanity did not change much in Gilbert's time but his clear
teachings had a telling effect on the minds of the learned. Friction
machines were produced in rapid succession and experiments and
observations multiplied. Gradually fear and superstition gave way to
scientific in-sight and in 1745 the world was thrilled with the news
that Kleist and Leyden had succeeded in imprisoning the uncanny agent
in a phial from which it escaped with an angry snap and destructive
force. This was the birth of the condenser, perhaps the most marvelous
electrical device ever invented.
Two tremendous leaps were made in the succeeding forty
years. One was when Franklin demonstrated the identity between the
gentle soul of amber and the awe-inspiring belt of Jupiter; the other
when Galvany and Volta brought out the contact and chemical battery,
from which the magic fluid could be drawn in unlimited quantities. The
succeeding forty years bore still greater fruit. Oersted made a
significant advance in deflecting a magnetic needle by an electric
current, Arago produced the electro-magnet, Seebeck the thermo-pile
and in 1831, as the crowning achievement of all, Faraday announced
that he had obtained electricity from a magnet, thus discovering the
principle of that wonderful engine—the dynamo, and inaugurating a
new era both in scientific research and practical application.
From that time on inventions of inestimable value have
followed one another at a bewildering rate. The telegraph, telephone,
phonograph and incandescent lamp, the induction motor, oscillatory
transformer, Roentgen ray, Radium, wireless and numerous other
revolutionary advances have been made and all conditions of existence
eighty-four years which have since elapsed, the subtle agents dwelling
in the living amber and loadstone have been transformed into cyclopean
forces turning the wheels of human progress with ever increasing
speed. This, in brief, is the fairy tale of electricity from Thales to
the present day. The impossible has happened, the wildest dreams have
been surpassed and the astounded world is asking: What is coming next?
ELECTRICAL POSSIBILITIES IN COAL AND IRON
Many a would-be discoverer, failing in his efforts,
has felt the regret to have been born at a time when everything has
been already accomplished and nothing is left to be done. This
erroneous impression that, as we are advancing, the possibilities of
invention are being exhausted, is not uncommon. In reality it is just
the opposite. Spenser has conveyed the right idea when he likened
civilization to the sphere of light which a lamp throws out in
darkness. The brighter the lamp and the larger the sphere the greater
is its dark boundary. It is paradoxical, yet true, to say, that the
more we know the more ignorant we become in the absolute sense, for it
is only through enlightenment that we become conscious of our
limitations. Precisely one of the most gratifying results of
intellectual evolution is the continuous opening up of new and greater
prospects. We are progressing at an amazing pace, but the truth is
that, even in fields most successfully exploited, the ground has only
been broken. What has been so far done by electricity is nothing
compared with what the future has in store. Not only this, but there
are now innumerable things done in old-fashioned ways which are much
inferior in economy, convenience and many other respects to the new
method. So great are the advantages of the latter that whenever an
opportunity presents itself the engineer advises his client to
"do it electrically."
Consider, in illustration, one of the largest
industries, that of coal. From this valuable mineral we chiefly draw
the sun's stored energy which is required to meet our industrial and
commercial needs. According to statistical records, the output in the
United States during the past year was 480,000,000 tons. In perfect
engines this fuel would have been sufficient to develop 500,000,000
horse-power steadily for one year, but the squandering is so reckless
that we do not get more than 5 per cent of its heating value on the
average. There is an appalling waste in mining, handling,
transportation, store and use of coal, which could be very much
reduced through the adoption of a comprehensive electrical plan in all
these operations. The market value of the yearly product would be
easily doubled and an immense sum added to the revenues of the
country. What is more, inferior grades, billions of tons of which are
being thrown away, might be turned to profitable use.
Similar considerations apply to natural gas and
mineral oil, the annual loss of which amounts to hundreds of millions
of dollars. In the very near future such waste will be looked upon as
criminal and the introduction of the new methods will be forced upon
the owners of such properties. Here, then, is an immense field for the
use of electricity in many ways, vast industries which are bound to be
revolutionized through its extensive application.
To give another example, I may refer to the
manufacture of iron and steel, which is carried on in this country on
a scale truly colossal. During the last year, notwithstanding
unfavorable business conditions, 31,000,000 tons of steel have been
produced. It would lead too far to dwell on the possibilities of
electrical improvements in the manufacturing processes themselves, and
I will only indicate what is likely to be accomplished in using the
waste gases from the coke ovens and blast furnaces to generate
electricity for industrial purposes.
Since in the production of pig-iron for every ton
about one ton of coke is employed, the yearly consumption of coke may
be put at 31,000,000 tons. The combustion in the blast furnaces
yields, per minute, 7,000,000 cubic feet of gas of a heating value of
110 B. T. units per cubic foot. Of this total, without making special
provision, 4,000,000 cubic feet may be made available for power
purposes. If all the heat energy of this gas could be transformed into
mechanical effort, it would develop 10,389,000 horse-power. This
result is impossible, but it is perfectly practicable to obtain
2,500,000 horse-power electrical energy at the terminals of the
dynamos.
In the manufacture of coke approximately 9400 cubic
feet of gas are evolved per ton of coal. This gas is excellent for
power purposes, having an average heating value of 600 B. T. units,
but very little is now used in engines, largely because of their great
cost and other imperfections. A ton of coke requires about 1.32 tons
of American coal; hence the total coal consumption per annum on the
above basis is nearly 41,000,000 tons, which give, per minute, 733,000
cubic feet of gas. Assuming the yield of surplus or rich gas to be
333,000 cubic feet, the balance of 400,000 cubic feet could be used in
gas engines. The heat contents would be, theoretically, sufficient to
develop 5,660,000 horse-power, of which 1,500,000 horse-power could be
obtained in the form of electric energy.
I have devoted much thought to this industrial
proposition, and find that with new, efficient, extremely cheap
and simple thermo-dynamic transformers not less than 4,000,000
horse-power could be developed in electric generators by utilizing the
heat of these gases, which, if not entirely wasted, are only in part
and inefficiently employed.
With systematic improvements and refinements much
better results could be secured and an annual revenue of $50,000,000
or more derived. The electrical energy could be advantageously used in
the fixation of atmospheric nitrogen and production of fertilizers,
for which there is an unlimited demand and the manufacture of which is
restricted here on account of the high cost of power. I expect
confidently the practical realization of the project in the very near
future, and look to exceptionally rapid electrical development in this
direction.
HYDRO-ELECTRIC DEVELOPMENT
Water-power offers great opportunities for novel
electrical applications, particularly in the department of
electro-chemistry. The harness of waterfalls is the most economical
method known for drawing energy from the sun. This is due to the fact
that both water and electricity are incompressible. The net efficiency
of the hydro-electric process can be as high as 85 per cent. The
initial outlay is generally great, but the cost of maintenance is
small and the convenience offered ideal. My alternating system is
invariably employed , and so far about 7,000,000 horse-power have been
developed. As generally used we do not get more than six-hundredths of
a horse-power per ton of coal per year. This water energy is
therefore equivalent to that obtainable from an annual supply of
120,000,000 tons of coal, which is about 25 per cent of the total
output in the United States. The estimate is conservative, and in
view of the immense waste of coal 50 per cent may be a closer guess.
We get better appreciation of the tremendous value of
this power in our economic development when we remember that, unlike
fuel, which demands a terrible sacrifice of human energy and is
consumed, it is supplied without effort and destruction of material
and equals the mechanical performance of 150,000,000 men—one and
one-half times the entire population of this country. These figures
are imposing; nevertheless, we have only begun the exploitation of
this vast national resource.
There are two chief limitations at present—one in
the availability of the energy, the other in its transmission to
distance. The theoretical power of the falling water is enormous. If
we assume for the rain clouds an average height of 15,000 feet and
annual precipitation of 33 inches, the 24 horse-power per square mile
is over 4000, and for the whole area in the United States more than
12,000,000,000 horse-power. As a matter of fact, the larger portion of
the potential energy is used up in air friction. This, while
disappointing to the economist, is a fortunate circumstance, for
otherwise the drops would reach the ground with a speed of 800 feet
per second—sufficient to raise blisters on our bodies, while hail
would be positively deadly. Most of the water, which is available for
power purposes comes from a height of about 2000 feet and represents
over one and one-half billion horse-power, but we are only able to use
an average fall of, say, 100 feet, which means that if all the
water-power in this country were harnessed under the existing
conditions only 80,000,000 horse-power could be obtained.
THE NEXT GREAT ACHIEVEMENT—ELECTRICAL CONTROL OF
ATMOSPHERIC MOISTURE
But the time is very near when we shall have the
precipitation of the moisture of the atmosphere under complete
control, and then it will be possible to draw unlimited quantities of
water from the oceans, develop any desired amount of energy, and
completely transform the globe by irrigation and intensive farming.
A Greater achievement of man through the medium of electricity can
hardly be imagined.
The present limitations in the transmission of power
to distance will be overcome in two ways—through the adoption of
underground conductors insulated by power, and through the
introduction of the wireless art. The first plan I have advanced years
ago. The underlying principle is to convey through a tubular conductor
hydrogen at a very low temperature, freeze the surrounding material
and thus secure a perfect insulation by indirect use of electric
energy. In this manner the power derived from falls can be transmitted
to distances of hundreds of miles with the highest economy and at a
small cost. This innovation is sure to greatly extend the fields of
electrical application. As to the wireless method, we have now the
means for economic transmission of energy in any desired amount and to
distances only limited by the dimensions of this planet. In view of
assertions of some misinformed experts to the effect that in the
wireless system I have perfected the power of the transmitter is
dissipated in all directions, I wish to be emphatic in my statement
that such is not the case. The energy goes only to the place where it
is needed and to no other.
When these advanced ideas are practically realized we
shall get the full benefit of water-power, and it will become our
chief dependence in the supply of electricity for domestic, public and
other uses in the arts of peace and war.
ECONOMY IN LIGHT AND POWER—ELECTRIC PROPULSION
In the great departments of electric light and power
immense opportunities are offered through the introduction of all
kinds of novel devices which can be attached to the circuits at
convenient hours for the purpose of equalizing the loads and
increasing the revenues from the plants. I have myself knowledge of a
number of new appliances of this kind. The most important among them
is probably an electrical ice machine which obviates entirely the use
of dangerous and otherwise objectionable chemicals. The new machine
will also require absolutely no attention and will be extremely
economical in operation, so that the refrigeration will be effected
very cheaply and conveniently in every household.
An interesting fountain, electrically operated, has
been brought out which is likely to be extensively introduced, and
will afford an unusual and pleasing sight in squares, parks, hotels
and residences.
Cooking devices for all domestic purposed are being
provides, and there is great demand for practical designs and
suggestions in this field. The same may be stated of electric signs
and other attractive means of advertising which can be electrically
operated. Some of the effects which it is possible to produce by
electric currents are wonderful and lend themselves to exhibitions,
and there is no doubt that much can be done in that direction.
Theaters, public halls and private dwellings are in need of a great
many devices and instruments for convenience and offer ample
opportunities to an ingenious and practical inventor.
A vast and absolutely untouched field is the use of
electricity for the propulsion of ships. The leading electrical
company in this country has just equipped a large vessel with
high-speed turbines and electric motors and has achieved a signal
success. Applications of this kind will multiply at a rapid rate, for
the advantages of the electrical drive are now patent to everybody. In
this connection gyroscopic apparatus will probably play an important
part, as its general adoption on vessels is sure to come. Very little
has yet been done in the introduction of electrical drive in the
various branches of industry and manufacture, and the prospects are
unlimited.
A FEW OF THE WONDERS TO COME
Books have already been written on the agricultural
uses of electricity, but the fact is that hardly anything has been
practically done. The beneficial effects of electricity of high
tension have been unmistakably established, and a revolution will be
brought about through the extensive adoption of agricultural
electrical apparatus. The safeguarding of forests against fires,
the destruction of microbes, insects and rodents will, in due course,
be accomplished by electrical means.
In the near future we shall see a great many new uses
of electricity aiming at safety, particularly vessels at sea. We shall
have electrical instruments for preventing collisions, and we shall
even be able to disperse fogs by electric force and powerful and
penetrative rays. I am hopeful that within the next few years wireless
plants will be installed for the purpose of illuminating the oceans.
The project is perfectly feasible, and if carried out will contribute
more than any other provision to the safety of property and human
lives at sea. The same plant could also produce stationary electrical
waves and enable vessels to get at any time accurate bearings and
other valuable practical data without resorting to the present means.
I t could also be used for time signaling and many other purposes of
similar nature.
Electrotherapy is another great field in which there
are unlimited possibilities for electrical applications.
High-frequency currents especially have a great future. The time will
come when this form of electrical energy will be available in every
private residence. I consider it quite possible that through their
surface actions we may do away with the customary bath, as the
cleaning of the body can be instantaneously effected simply by
connecting it to a source of currents or electric energy of very high
potential, which results in the throwing off of dust or any small
particles adhering to the skin. Such a dry bath, besides being
convenient and time-saving, would also be of beneficial therapeutic
influence. New electric devices for use of the deaf and blind are
coming and will be a blessing to the afflicted.
In the prevention of crime electrical instruments will
soon become an important factor. In court proceedings electric
evidence will often be decisive. In a time not distant it will be
possible to flash any image formed in thought on a screen and render
it visible at any place desired. The perfection of this means of
reading thought will create a revolution for the better in all our
social relations. Unfortunately, it is true, that cunning lawbreakers
will avail themselves of such advantages to further their nefarious
business.
TELEGRAPHIC PHOTOGRAPHY AND OTHER ADVANCES
Great improvements are still possible in telegraphy
and telephony. The use of a new receiving device which will be shortly
described, and the sensitiveness of which can be increased almost
without limit, will enable telephoning through aerial lines or cables
however long by reducing the necessary working current to an
infinitesimal value. This invention will dispense with the necessity
of resorting to expensive constructions, which, however, are of
circumscribed usefulness. It will also enormously extend the wireless
transmission of intelligence in all its departments.
The next art to be inaugurated is that of picture
transmission by ordinary telegraphic methods and existing apparatus.
This idea of telegraphing or telephoning pictures is old, but
practical difficulties have hampered commercial realizations. A number
of improvements of great promise have been made, and there is every
reason to expect that success will soon be achieved.
Another valuable novelty will be a typewriter
electrically operated by the human voice. This advance will fill
a long-felt want, as it will do away with the operator and save a
great deal of labor and time in offices.
A new and extremely simple electric tachometer is
being prepared for the market, and it is expected that it will prove
useful in power plants and central stations, on boats, locomotives and
automobiles.
Many municipal improvements based on the use of
electricity are about to be introduced. We have soon to have
everywhere smoke annihilators, dust absorbers, ozonizers, sterilizers
of water, air, food and clothing, and accident preventers on streets,
elevated roads and in subways. It will become next to impossible to
contract disease germs or get hurt in the city, and country folk will
got to town to rest and get well.
ELECTRIC INVENTIONS IN WAR
The present international conflict is a powerful
stimulus to invention of devices and implements of warfare. An
electric gun will soon be brought out. The wonder is that it was not
produced long ago. Dirigibles and aeroplanes will be equipped with
small electric generators of high tension, from which the deadly
currents will be conveyed through the wires to the ground. Battleships
and submarines will be provided with electric and magnetic feelers so
delicate that the approach of any body underwater or in darkness will
be detected. Torpedoes and floating mines are almost in sight which
will direct themselves automatically and without fail get in fatal
contact with the object to be destroyed. The art of telautomatics, or
wireless control of automatic machines at a distance, will play a very
important part in future wars and, possibly, in the next phases of the
present one. Such contrivances which act as if endowed with
intelligence will be used in innumerable ways for attack as well as
defense. They may take the shape of aeroplanes, balloons, automobiles,
surface or under-water boats, or any other form according to the
requirement in each special case, and will be of greater range and
destructiveness than the implements now employed. I believe that
the telautomatic aerial torpedo will make the large siege gun, on
which so much dependence is placed at present, obsolete.
A volume might be filled with such suggestions without
exhausting the possibilities. The advance even under the conditions
existing is rapid enough, but when the wireless transmission of energy
for general use becomes a practical fact the human progress will
assume the character of a hurricane. So all-surpassing is the
importance of this marvelous art to the future existence and welfare
of the human race that every enlightened person should have a clear
idea of the chief factors bearing on its development.
THE POWER OF THE FUTURE
We have at our disposal three main sources of
life-sustaining energy—fuel, water-power and the heat of the sun's
rays. Engineers often speak of harnessing the tides, but the
discouraging truth is that the tidewater over one acre of ground will,
on the average, develop only one horse-power. Thousands of mechanics
and inventors have spent their best efforts in trying to perfect wave
motors, not realizing that the power so obtained could never compete
with that derived from other sources. The force of wind offers much
better chances and is valuable in special instances, but is by far
inadequate. Moreover, the tides, waves and winds furnish only periodic
and often uncertain power and necessitate the employment of large and
expensive storage plants. Of course, there are other possibilities,
but they are remote, and we must depend on the first of three
resources. If we use fuel to get our power, we are living on our
capital and exhausting it rapidly. This method is barbarous and
wantonly wasteful, and will have to be stopped in the interest of
coming generations. The heat of the sun's rays represents an immense
amount of energy vastly in excess of water-power. The earth receives
an equivalent of 83 foot-pounds per second for each square foot on
which the rays fall perpendicularly. From simple geometrical rules
applying to a spherical body it follows that the mean rate per square
foot of the earth's surface is one-quarter of that, or 20 3/4
foot-pounds. This is to say over one million horse-power per square
mile, or 250 times the water-power for the same area. But that is only
true in theory; the practical facts put this in a different aspect.
For instance, considering the United States, and taking into account
the mean latitude, the daily variation, the diurnal changes, the
seasonal variations and casual changes, this power of the sun's rays
reduces to about one-tenth, or 100,00 horse-power per square mile, of
which we might be able to recover in high-speed low-pressure turbines
10,000 horse-power. To do this would mean the installment of apparatus
and storage plants so large and expensive that such a project is
beyond the pale of the practical. The inevitable conclusion is that
water-power is by far our most valuable resource. On this humanity
must build its hopes for the future. With its full development and a
perfect system of wireless transmission of the energy to any distance
man will be able to solve all the problems of material existence.
Distance, which is the chief impediment to human progress, will be
completely annihilated in thought, word and action. Humanity will be
united, wars will be made impossible and peace will reign supreme.
