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We examine an article written by Nikola Tesla entitled "The True Wireless," which appeared in the Electrical Experimenter magazine in May of 1919. His essay is analyzed as an example of the inability of a scientist or inventor to assimilate a paradigm shift in his discipline, and we use the language and thought of Thomas Kuhn in this discussion. The paradigm shift in question was created by Maxwell and Hertz in the latter third of the 19th century, a shift that explained the existence and generation of electromagnetic waves-the basis for wireless telegraphy and eventually radio. We also focus on the magazine in which Tesla's piece appeared and consider why the article might have been written and accepted for publication. "The Hertz wave theory of wireless transmission may be kept up for a while, but I do not hesitate to say that in a short time it will be recognized as one of the most remarkable and inexplicable aberrations of the scientific mind which has ever been recorded in history."
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Volume 30, 2017 1
Paradigm Lost: Nikola Tesla’s True Wireless
© 2017 A. David Wunsch
We examine an article written by Nikola Tesla entitled “The True Wireless,” which
appeared in t he Electrical Experimenter magazine in May of 191 9. His essay is analyzed
as an example of the inability of a scientist or inventor to assimilate a paradigm
shift in his discipline, and we use the language and thought of Thomas Kuhn in this
discussion. The paradigm shift in question was created by Maxwell and Hertz in the
latter third of the 19th century, a shift that explained the existence and generation
of electromagnetic waves—the basis for wireless telegraphy and eventually radio.
We also focus on the ma gazine in which Tesla’s piece appeared and co nsider why the
article might have been written and accepted for publication.
“The Hert z wave theory of wireless transmi ssion may be kept up for a while, but I d o not
hesitate to say that in a sho rt time it will be recognized as o ne of the most remarkable and
inexplicab le aberrations of the scientic mind which has ever been recorded in history.”
—Nikola Tesla, “The True Wireless” 1919
“… the man who continues to resist after his whole profession has been converted has
ipso facto ceased to be a scie ntist.
—Thomas Kuhn, The Structure of Scientic Revolu tions 1962
The Paradigm
For historians of radio and the wireless
telegraph, one of the strangest docu-
ments they are apt to encounter is an
article entitled “e True Wireless” that
was published in the May  issue
of the popular magazine, the Elec-
trical Experimenter. e author was
the renowned Serbian-born inventor,
Nikola Tesla (–). Tesla spent
most of his professional life in the
United States, and by  he was just
past the peak of his fame—a man as
nearly well known to the general public
as Edison. He was a contributor to the
Sunday supplements of newspapers,
where he described his latest proposed
inventions such as a weapon that would
make war obsolete by creating an enor-
mous tidal wave.1
Although his reputation as an
inventor may have faded, he persists
today as a cult gure. A web search
will lead to sites proclaiming that he
invented radio, radar, x-rays, alternat-
ing current, the laser, the transistor,
and limitless free energy. His name
also endures as the brand of a pioneer-
ing high-priced electrical automobile.
2 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
ere is some irony in this—the car is
powered by batteries that supply direct
current (DC), while Tesla’s great accom-
plishment resides in his contribution
to the generation and distribution of
polyphase alternating current (AC).
He developed an ingenious device, the
induction motor, that is ideally suited
to polyphase AC because of the ease
with which such current creates the
rotating magnetic eld required by
many motors.
Readers of this paper should have
at their disposal a copy of “e True
Wireless,” which can be found on the
Internet.2 Note that the insert appear-
ing in the article was written by the
magazine’s editor, Hugo Gernsback,
who asserted, “Dr. Tesla shows us that
he is indeed the ‘Father of wireless.’”
Tesla is referred to variously as an engi-
neer, physicist, scientist, and inventor
on many websites, including the Wiki-
pedia, which contain his biography.
Historically, this blurring of occupa-
tions has a distinguished lineage: Gali-
leo, for example, invented telescopes
and other instruments and was also
an astronomer, and the transistor was
invented by men trained as scientists,
not engineers.
A Paradigm Missed
Had Tesla’s paper appeared een years
before—circa—its content would
be unremarkable. Coming as it does in
, just before the era of broadcast
radio, it becomes useful as a notable
example, in the eld of science and
technology, of an inventor’s failure to
grasp what the distinguished historian
of science omas Kuhn has described
as a “paradigm shi.”
is term rst appears in Kuhn’s
book e Structure of Scientic Revo-
lutions published in . e work is
among the most cited scholarly books
produced in the last half of the th cen-
tury and has been in print in various
editions for over  years. We refer here
to the rd edition of .3 e expres-
sion paradigm shi has entered every-
day language, and its use has steadily
increased since Kuhn coined the
phrase. e concept will be employed
here in the discussion of Tesla’s paper.
What does Kuhn mean by this
term? In the sciences, he asserts that
a paradigm derives from “universally
recognized scientic achievements that
for a time provide model problems and
solutions to a community of practitio-
ners.” e word “model” is key here.
e Greek-Egyptian astronomer Ptol-
emy (– AD) had a model of what
we now call our solar system: his earth
was at its center, and the sun revolved
around the earth. e concept has a
limited use—it does explain sunrise
and sunset, but as mankind’s knowl-
edge of the planets and stars increased,
it became unworkable. Copernicus,
Galileo, Kepler, and Newton killed the
old model—their work, which began
circa and occupied nearly two
centuries, led to a classic paradigm
shi. e shi describes the discarding
of an old model whose use is unfruit-
ful and untenable in favor of a new
paradigm that more gracefully and
convincingly describes recent experi-
mental evidence.
Volume 30, 2017 3
For our present discussion, the
important paradigm shi began with
the Scotsman James Clerk Maxwell
(–). Consider what Nobel
Laureate Richard Feynman said
about Maxwell’s work of the period
–:From a long view of the
history of mankind—seen from, say, ten
thousand years from now—there can
be little doubt that the most signicant
event of the th century will be judged
as Maxwell’s discovery of the laws of
Maxwell produced a paradigm,
or a model, for light: it was an elec-
tromagnetic wave having transverse
electric and magnetic elds. e theory
described a wave moving at the speed of
light that could be generated by electri-
cal means, and it did not specify a wave
length—it could be, for example, 
nanometers (like visible light, whose
wavelengths were known in Maxwell’s
era), or around  meters (like broad-
cast AM radio of our time).
In the late 
century, Newton
had maintained that light consisted of
streams of particles, which he named
corpuscles; his prestige was such that his
model still had some adherents as late
as Maxwell’s era, although there was
much evidence favoring a wave theory.
To further complicate matters, others
analyzed light as a ray that describes
the path of the light energy.
We now come to a narrative famil-
iar to many readers. In the period
–, the German physicist
Heinrich Hertz carried out a series of
experiments in which he generated a
wave that exhibited wavelengths on the
order of meters, possessed a measur-
able electromagnetic eld, and to a fair
approximation moved at the known
speed of light.6 ese waves could be
reected, polarized, and diracted—
just as visible light, whose properties
had been studied for several centuries.
Had the Nobel Prize been awarded in
the lifetimes of Maxwell and Hertz,
they would surely have been win-
ners. Hertz’s work was published in
the period – and served as a
stimulus to such people as Guglielmo
Marconi, Oliver Lodge, and Karl F.
Braun, who sought to employ Hertz’s
discovery in the eld of wireless teleg-
raphy. e story is well told in the book
by Aitken.7
Tesla recounts a meeting with
Hertz in the document we are study-
ing: he traveled to Hertz’s laboratory in
Bonn, Germany, in  and describes
in “e True Wireless” an unfruitful
encounter where he informs Hertz
that he had been unable to reproduce
his results. If we believe Tesla, the two
parted “sorrowfully” with our narrator
subsequently regretting his trip.
also informs us that later, even hav-
ing developed a “wireless transmitter
which enabled me to obtain electro-
magnetic activities of many millions
[sic] of horse-power,” he was unable
to “prove that the disturbances ema-
nating from the oscillator were ether
vibrations akin to those of light…
Unable to generate what soon became
known as Hertzian waves, and having
read articles describing such waves over
the eighteen-year period preceding this
article, he remarks, “e Hertz-wave
4 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
theory, by its fascinating hold on the
imagination, has stied creative eort
in the wireless art and retarded it for
twenty-ve years.
By the time Tesla wrote his article,
wireless telegraphy had been a business
for nearly  years—and had grown
into a very big one at that. When the
United States entered World War I in
, the Marconi Wireless Telegra-
phy Company of America (American
Marconi) had outtted  wireless
stations on ships and possessed 
coastal stations for ship-to-shore and
international communication.
Navy took these over at the beginning
of the war. At the cessation of the war,
British Marconi was eager to buy exclu-
sive rights to the Alexanderson alterna-
tors from General Electric; these were
powerful and ecient successors to the
spark gap and arc transmitters used
earlier in wireless telegraphy. Initially,
they planned to spend over M on 
alternators and employ them both in
their own corporation and in Ameri-
can Marconi.10 If, as Tesla alleges, the
big business of wireless telegraphy did
not employ Hertzian waves, how did it
operate? He specically denies that the
“disturbances” (a name he uses in lieu
of Hertz’s waves) emanating from an
oscillator “were ether vibrations akin
to that of light.”
It is interesting to examine the lan-
guage of his paper. He speaks of “some
kind of space waves” and “transversal
vibrations in the ether,” and except to
disparage them, he does not refer to
Hertz’s (or Hertzian) waves. By ,
his words and thinking were archaic.
e terminology in the discourse of
radio and wireless telegraphy engineer-
ing had evolved since Hertz’s work and
the growth of international wireless
We now employ the Google Book’s
Ngram Viewer, a piece of free Internet
soware that quanties how frequently
a word turns up in a large number of
books during a specied time period.
e output of this soware is a graph
showing the number of mentions in
books versus time (in years) for a word
or phrase supplied. e frequency of
use of the term Hertzian waves over
more than a century is shown in
Fig.. We see the term gaining cur-
rency beginning with Hertz’s famous
experiments and reaching a peak at
about the time of Tesla’s paper. It is
not hard to understand that it subse-
quently lost popularity. A search of
the term electromagnetic waves, which
ultimately replaced Hertzian waves, is
shown in Fig. .
As it became clear to the engineer-
ing community that the waves gener-
ated by Hertz were merely a part of the
electromagnetic spectrum—one which
was to become increasingly exploited
by broadcast AM radio, television, and
FM broadcasting—the locution Hertz-
ian waves would have seemed anach-
ronistic. It is evident that at the time
of Tesla’s writing, the term “Hertzian
waves” had already been eclipsed by
“electromagnetic waves.” Incidentally,
an Ngram of the term “radio waves”
displays a curve much like that for elec-
tromagnetic waves. Both gained favor
at the same time.
Volume 30, 2017 5
Tesla “Disproves” Hertzian Theory
Electricity and Hydraulic Analogies
How did Tesla explain wireless commu-
nication without Hertzian waves or its
synonyms? e answer is fascinating.
He used a shy version of alternating
circuit theory. A close reading of “e
True Wireless” reveals that he promoted
a form of circuit theory employing but
a single wire—in other words, there is
no real circuit such as those who under-
stood the subject are accustomed to. He
also maintains that the earth itself can
function—must function—as this lone
wire. He seeks to explain this with a
labored hydraulic (uid) analogy that is
illustrated in Fig.  of his paper, which
is reproduced here as Fig. .
Of course, you can send a distur-
bance down a water lled pipe with-
out employing a return circuit—just
strike one end with a hammer. His
analogy proves nothing, but its use
is understandable. When Tesla was
in college in the late ’s and early
’s, alternating current theory was a
new and dicult subject.11 If he learned
Fig. 1. Frequency of use of the term “Hertzian waves.” (Google Ngram)
Fig. 2. Frequency of use of the term “electromagnetic waves.” (Google Ngram)
6 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
it there, or, as seems likely, on his own
aer college, he would have encoun-
tered textbooks that sought to treat
this discipline using analogies drawn
from hydraulics—a much older and
better-understood subject.
It was not
uncommon then to use the word “pres-
sure,” taken from uid mechanics,
where we now use “voltage” or “elec-
trical potential.” Such analogies, which
might employ water wheels to repre-
sent inductors and elastic diaphragms
as proxies for capacitors, convey only
an intuitive feeling for AC circuits
and are of no use for communication
systems employing electromagnetic
us, Tesla attempted to apply a
dubious electric circuit approach where
it had no validity. In fact, one wonders
why no one asked him if the return
wire in the circuit could be eliminated,
then why not also the wire that carries
the current that is outgoing from the
generator. Had he taken that radical
step, he might have been on his way
to understanding communication
between two antennas in the absence
of any earth.14
In criticizing Tesla for his wrong-
headed model, are we in fact guilty
of what has become known as Whig
history? e term Whig history was
introduced by the distinguished Eng-
lish historian Sir Herbert Buttereld
in . It can refer to an unfair judg-
ment of historical gures and their
actions that are based on our present
Fig. 3. Tesla’s uid “circuit.” (True Wireless, Fig. 4)
Volume 30, 2017 7
knowledge of what is humane and pro-
gressive and acceptable. For example, to
condemn omas Jeerson for writing
in the Declaration of Independence “All
men are created equal” (where are the
women?) would be to engage in Whig
history. In the sciences, Whig history
has a similar meaning: it would be to
criticize a scientist or inventor of the
past for failing to use concepts that we
now take for granted.15
From our present perspective, Tes-
la’s not using a wave model to explain
radio seems bizarre, but given what was
known in , are we being unfair and
leaving ourselves open to the accusation
of Whiggishness? An example of Whig
history of science would be to condemn
Ptolemy for his earth centered view of
astronomy. Given the tools at his dis-
posal, his mistake is understandable.
And to disparage Maxwell for his fre-
quent use of the term ether—when we
know that the concept is not valid—
would be Whig history. I will seek to
explain in what follows that I have not
fallen into the trap of Whig history in
discussing Tesla.
Inuence of Mountains or Obstacles
Tesla seeks to disprove Hertzian wave
theory as a means of communica-
tion with several examples. Consider
his Fig. , reproduced here as Fig. .
Tesla claims that “unless the receiver
is within the electrostatic inuence
of the mountain range”—in what we
would now call “the near eld of the
antenna”—the signals at the receiver
“are not appreciably weakened by
the presence of the latter because the
signal passes under it [italics added]
Fig. 4. Tesla analyzes the eect of an obstacle. (True Wireless, Fig. 17)
8 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
and excites the [receiving] circuit in
the same way as if it is attached to an
energized wire.” No radio propagation
engineer would have accepted such an
argument in . Indeed, the receiver
might well detect the transmitted sig-
nal, but not for the reasons stated by
Tesla. No model of wave propagation
asserts that the signal goes under the
Following the work of Hertz, it was
apparent that laws of optics could be
applied to electrically generated waves.
ere would have been no problem in
explaining the reception of waves by a
detector lying on the shaded side of the
mountain—it would be described as
Fresnel diraction, a theory put forth
by the eponymous French physicist
in the period –.
e theory
asserts, in part, that the greater the
wavelength used, the stronger the sig-
nal that makes its way into the opti
cal “dark side,” provided the distance
from the diracting edge (here, the
mountain top) is small measured in
wavelengths.18 Given the long wave
lengths employed by Tesla (kHz =>
 km. =>  miles), a number taken
from Fig. in his article, there is no
trouble in explaining wireless recep-
tion on the far side of the mountain. By
the time Tesla published this piece, the
subject of diraction of electromagnetic
waves had become sophisticated and
had engaged the attention of a number
of distinguished mathematicians.
If the mountain is modeled as a
hemispherical impediment to the
wave, and if the earth is a good con-
ductor, then the problem of scattering
by the mountain can be attacked using
the method of images. e problem
becomes that of a plane wave incident
upon a sphere. is problem had been
solved in the period – by Debye
and Mie and would also show a signal
in the optical shadow cast by the hemi-
spherical mountain.19
In the period beginning in  and
ending in the era of Tesla’s writing, the
Scottish mathematician H. M. Macdon-
ald had treated waves from a Hertzian
dipole diracted from the earth, which
he modeled as a perfectly conducting
His work was improved by
the great French scientist and phi-
losopher, Henri Poincaré, who in the
period – converted Macdon-
ald’s series of Bessel functions into a
denite integral that could be better
evaluated. e German mathematical
physicist Arnold Sommerfeld, unlike
his predecessors, treated the earth as
an imperfectly conducting surface,
although he simplied matters by mak-
ing the earth at. He placed a verti-
cal, electrically short dipole above the
earth and derived an expression for the
resulting electric and magnetic elds.
His results of  were expressed in
terms of an integral that he evaluated
asymptotically for an observer far from
the antenna. He found that a surface
wave had been generated, and his the-
ory nicely supported that of another
German, Jonathan Zenneck, whose
less rigorous work had led to what
became known as the Zenneck wave,
which existed on the ground at some
distance from the antenna. e latter
turned out to be the asymptotic solution
Volume 30, 2017 9
of Sommerfeld’s theory. In , the
German mathematician Herman Weyl
solved Sommerfeld’s conguration and
ended up with a dierent approach that
did not contain Zenneck’s wave. is
result caused Sommerfeld to rework his
solution, and his new ndings did not
agree with Zenneck.
In short, the rst two decades of the
century was a lively and sometimes
contentious period in the theory of
radio wave propagation, but there is no
hint of this in Tesla’s paper. Nor is there
any indication in anything he wrote
that he had the sophisticated math-
ematical skills to comprehend what was
being written by the people cited above.
ere were, of course, great inventors
with minimal knowledge of higher
mathematics (think of Edison, Morse,
Bell) but these largely belonged to the
th century, and one does see Tesla as
part of that tradition. His clinging to
a sketchy circuit theory explanation
seems pathetic. Incidentally, as early
as , a textbook of Henri Poincaré
had addressed the primacy given to
currents owing through the earth in
Tesla’s model of wireless telegraphy. He
points out that if a coherer is placed in
a hole in the ground “it will operate
[as a detector of wireless telegraphy]
when uncovered; if the hole be lled
with earth, the oscillations produce
no eect. We must look for something
more than earth currents to explain
the phenomena.”
Recall that the most
common detector in use at that time
was the Branly coherer.
Putting aside theoretical consider-
ations, Tesla’s paper is notable for the
omission of major empirical ndings
contained in the famous and practi-
cal Austin-Cohen formula, a concise
expression that describes the strength
of the electric eld experienced by a
receiving antenna when both receiver
and transmitter are over the ocean.
Louis Winslow Austin and Louis Cohen
had worked for the U.S. Navy in the
early ’s, making shipboard electri-
cal measurements of the eld radiated
from various transmitters manufac-
tured by Reginald Fessenden’s com-
pany, the National Electric Signaling
Company, or NESCO. By , the two
men had devised a successful empirical
formula that gives the received eld.22
Ir = . Ishh e-ad /√λ.
Here I
is the current received by an
antenna driving an impedance of 
ohms, Is is the transmitting antenna’s
current, h
and h
are the lengths of the
two vertical antennas, l is the wave
length, d is the distance separating the
antennas, and a = .. Lengths are
in kilometers and currents in amperes.
e formula was eective only dur-
ing the day and was so useful that it
became the basis for testing new theo-
retical predictions of received elds.
e presence of the square root of the
wavelength in the exponent was later
derived theoretically by the English
mathematician G. N. Watson and
published in , only a few months
after Tesla’s paper.
Tesla, speaking of the formula, states
unequivocally “… the actions at a dis-
tance cannot be proportionate to the
10 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
height [length] of the antenna and the
current in the same,” which is in direct
contradiction to what the much-used
equation asserts. Tesla’s statement
“the current in the same” is especially
puzzling, not only because it had been
established experimentally but also
because he has essentially been using
alternating circuit theory, in a strange
form, and the device he is employing—
an antenna, and a conducting earth—
are mathematically linear and should,
according to linear circuit analysis,
create a response in linear proportion
to the current exciting the antenna.
Strange to say, Tesla then uses Aus-
tin-Cohen to reject Hertzian waves,
saying that, “…I cannot agree with
him [Austin] on this subject. I do not
think that if his receiver was aected
by Hertz waves he could ever establish
such relations as he has found.” So, on
the one hand, he rejects the famous for-
mula but then embraces it as a means
to argue against Hertzian wave theory.
Let us now study Fig. , in Tesla’s
paper, reproduced here in Fig. . He
has now introduced a second moun-
tain that is further from the transmitter
than the one in the previous gure. He
argues that if Hertzian wave theory
were true, then the second mountain
“could only strengthen the Hertz wave
[at the receiver] by reection, but as a
matter of fact it detracts greatly from
the received impulses because the elec-
trical niveau between the mountains is
raised…” [niveau is a French word for
level surface].
What Tesla fails to understand here
is that without knowing the wavelength
of the radiation, the separation of the
two mountains, and the position of the
antenna between them, we can make
Fig. 5. Tesla considers the eect of two hills. (True Wireless, Fig. 18)
Volume 30, 2017 11
no statement about the enhancement or
reduction of the signal at the receiver
caused by the presence of the second
mountain. In fact, using elementary
wave theory or a transmission line
analog, we can argue that if the two
mountains are separated by half a
wavelength and if the receiver is mid-
way between them, and if the soil is
of reasonably high conductivity, then
we have what is called a standing wave
between the mountains. In this case,
the eect of the more distant mountain
is to enhance the signal at the receiver.
ere are waves moving from right to
le and vice-versa between the moun-
tains. Such an arrangement, when set
up in a room, as Hertz did in his famous
experiment published in , is known
as an interferometer.24
Kuhn tells us that if we want to see
what constitutes “normal science” and
the paradigms it embraces, we should
look at the textbooks of that era.25 By
, we can say condently that the
paradigm shi created by Maxwell and
Hertz had taken hold and was part of
normal science. is was the date of
publication of Poincaré’s book, whose
chapters ,  and  are devoted to the
propagation of waves along wires,
dielectrics, and air. It seems evident
that Tesla was not reading the textbooks
of his epoch.
Tesla and Antenna Theory
Another puzzling segment of Tesla’s
anti-Hertz diatribe is his Fig. , shown
below as Fig. . Tesla would have us
believe that the antenna on the right
Fig. 6. Tesla considers a straight and bent antenna. (True Wireless, Fig. 16)
12 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
(which nowadays is called “an inverted
L”) is just as eective as a receiver or
transmitter as the straight antenna
on the le. He claims that he has per-
formed an experiment that supports
this conclusion. He also asserts that
the experiment proves that “currents
propagated through the ground, and
not … space waves” is the reason for
true wireless telegraphy.
In , an understanding of the
theory of receiving antennas was still
fairly primitive.
And it was only in
, with the work on reciprocity of
John R. Carson at Bell Labs, that the
tools that had been developed to ana-
lyze transmitting antennas could be
brought to bear on receiving anten-
So, we must not be harsh in
condemning Tesla for his wrongful
assertion. However, it was known as
early as  that if antennas are placed
above a at highly conducting earth,
one can invoke the method of images
for analyzing them.
It was well known
before  that if the earth is a good
conductor, the electric eld of a propa-
gating radio wave would be primarily
perpendicular to the earth, and the eld
strength would be proportional to an
integral of the current along the vertical
portion of the antenna.
It should have been apparent to
Tesla that if a transmitting vertical
wire antenna is small, measured in
wavelengths, and has the shape of the
antenna on the le of Fig. , and if it
is now bent into the shape shown on
the right, then the electric eld nor-
mal to a at highly conducting earth is
However, the situation here
is potentially quite complicated. e
diculty occurs with an imperfectly
conducting earth. Marconi, in ,
described to the Royal Society an array
he built consisting of inverted L anten-
nas and observed that the array broad-
casts most eectively in the direction of
the arrow shown below, i.e., away from
the horizontal element.
Fig.  is taken
from Principles of Wireless Telegraphy
by G.W. Pierce, published in .31
Jonathan Zenneck, in the same era
as Pierce, describes the work of H. von
Hoerschelmann, a student of Arnold
Sommerfeld, who apparently was the
rst to explain the directive proper-
ties of Marconis antenna. His earth
is assumed to be imperfectly conduct-
ing. He includes the vertical portions
of the current induced in the earth
directly under the horizontal wires of
the array.32 e upshot is that whether
one assumes a highly conducting earth
or one of imperfect conductivity (as is
required for Marconi’s antenna), Tesla’s
assertion “that the antennas can be put
out of parallelism without noticeable
change in action on the receiver” is
utterly wrong. Marconis inverted L
was constructed in the year , and
the explanation by Hoerschelmann was
Fig. 7. Marconi’s directional inver ted L antenna.
(G. W. Pierce, Principles of Wireless Telegraphy,
1910, p. 298)
Volume 30, 2017 13
published in Zenneck’s book, which
came out in German in , both well
before Tesla’s paper.33
Skin Eect
Tesla repeatedly speaks of his system
of wireless telegraphy implemented by
sending messages through the earth.
Here he displays his ignorance of what
is now referred to as “skin eect”: that
alternating currents have a marked
tendency to cling to the outside (skin)
of conductors. Knowledge of this goes
back to the work of the Englishman,
Sir Horace Lamb, in  and was
advanced further by his countryman,
Oliver Heaviside, in .
e results
showed that the higher the frequency
in use, the greater the tendency for the
current to adhere to the outside of the
It is especially puzzling that Tesla
does not mention this phenomenon
as he took advantage of it in arranging
for photographs of himself enveloped
by sparks.35 e frequency of the gen-
erator he was using was such that the
energy would not penetrate deeply into
his body, which meant that although
he might have been burnt, he would
not have been electrocuted. In an 
lecture before the Franklin Institute
in Philadelphia, he sought to explain
his not being shocked with a confused
By , skin eect and the concept
of skin depth (the depth of penetra-
tion of the current) would have been
in the better electrical engineering
textbooks.37 We can calculate how far
a wave might penetrate into a mountain
in the United States where typical soil
conductivity, s = . mhos/meter and
the relative permittivity, e
= .
will assume a frequency f =  kHz.
Using the standard formula for skin
depth that applies when conduction
current greatly exceeds displacement
current,39 we have
δ =
π f σ
Here d is the skin depth and m is the
permeability of the soil, assumed here
to be nonmagnetic. e skin depth for
the numbers chosen here is about 
meters. It is virtually impossible for
the signal that Tesla imagines to pen-
etrate a mountain having these typical
Dismissal of Gliding Waves
Let us now focus on Tesla’s Fig. 
(shown here as Fig. ) and his accom-
panying discussion. At the very top of
his gure Tesla has the caption, “Hertz’s
waves passing o into space through
the earth’s atmosphere.” To some-
one acquainted with even elementary
antenna theory, the picture is a puzzle.
It depicts what appears to be a vertical
antenna fed by a generator connected
between the base of the antenna and the
earth. In , such an antenna would
likely be of small height when measured
in the wavelengths in use. Using the
method of images and antenna analysis
dating from the turn of that century,
it should have been apparent that no
radiation propagates along the axis
of the antenna; instead, the radiation
14 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
tends to be focused along the ground. In
fact, if the current in amperes along the
antenna is I
, then elementary antenna
theory establishes that the strength of
the electric eld is at a distance r from
the antenna, above the earth, is given by
Eθ = Iπh sinθ for  ≤ θπ /  ,
where h is the length of the antenna,
l is the wavelength in use and r is the
distance of the observer from the
All the distances are in
meters. e meanings θ and Eθ should
be evident from Fig. .
Observe that directly above the
antenna corresponds to q =, so that
sinq = , which indicates there is no
radiation normal to the earth, while
along the earth q =  degrees, and the
radiation is maximum, which might
suggest a wave gliding along the sur-
face of the earth, provided we are close
enough to the antenna to neglect the
earth’s curvature. is result would
have certainly been known well before
. e book Robison’s Manual of
Radio Telegraphy and Telephony for
Fig. 8. Tesla condemns the “Gliding Wave.” (True Wireless, Fig. 13)
Fig. 9. Electric eld an d spherical coordinates.
Volume 30, 2017 15
the use of Naval Electricians, published
in , contains the following dia-
gram showing the direction of electric
lines (see Fig. ).41 It illustrates that a
monopole antenna radiating above a
at perfectly conducting ground tends
to radiate in a direction parallel to the
ground and not in a direction along
the axis of the antenna. is is not a
polar plot of the eld strength vs. angle
but a picture showing the direction of
the electric eld at various locations.
Incidentally, one can argue that there
is no radiation along the axis of the
antenna even if the ground has imper-
fect conductivity.42
Tesla specically condemns any
theory that claims “[space waves] pass
along the earths surface and thus aect
the receivers. I can’t think of anything
more improbable than this ‘gliding
wave’ theory which… [is] contrary to all
laws of action and reaction.” Of course,
this gliding wave concept that we would
now call a “surface wave” did describe
daytime radio propagation and was
central to the work of such theorists as
Sommerfeld, Zenneck, and Watson.43
Tesla Debunks the Ionosphere
Warming to the task of diminishing
other theorists, Tesla then damns what
was then only a conjecture: the belief in
what was then known as the Kennelly-
Heaviside layer. We now call this the
ionosphere—a set of layers of three or
more ionized gases in the earth’s upper
atmosphere. It was rst postulated, as a
single layer, in  by Arthur Kennelly
and Oliver Heaviside, working inde-
pendently, as a way of explaining how
radio waves propagate beyond the hori-
zon.44 Although its existence and height
were not veried experimentally until
 by the Englishman Edward Apple
ton, for which he was later awarded the
Nobel Prize, its presence was generally
accepted in , especially as a means
to explain the long distances that radio
waves would propagate at night.45 Tes la
tells us, “I have noted conclusively that
there is no Heaviside layer, or if it exists
it is of no eect.” One wonders if he
recanted this statement aer Appleton’s
Communication with Airplanes
Among the more perplexing aspects
of Tesla’s article is his discussion tied
to his Fig. . He is showing here in
Fig. a “Hertz oscillator” suspended
in the air, and uses this arrangement
to explicate something that became
well known during World War I: an
airplane could communicate with a
wireless receiver on the ground. Also
known, but not discussed by Tesla,
was that two airplanes in the air might
experience radio contact with each
Fig. 10. Electric eld lines of a short monopole
antenna. (Manual for U.S. Nav y Electricians, 1918)
16 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
What Tesla must explain is how his
transmitter in the air might communi-
cate with the receiver on the ground in
spite of its not having a direct connec-
tion to the earth that would be capable
of eectively launching his crucial earth
currents. His explanation is that “we are
merely working through a condenser.”
Stating incorrectly there is a capacity
that “is a function of a logarithmic ratio
between the length of the conductor
and the distance from the ground,” he
says the receiver is aected in the same
manner as with an ordinary transmit-
ter. Evidently, we are to believe that the
capacitance between earth and ground
makes possible the earth currents cru-
cial to his argument.
e formula for the capacity of a
wire that he is most likely referring to
would have been well known by the
s when it already had appeared in
textbooks and handbooks:46
C = . L picofarads.
 ln
is expression is the capacity of a
wire of length L above, and parallel to,
the earth’s surface, which is assumed to
be highly conducting. An airplane in
ight dragging a wire antenna behind
itself would create this situation. e
wire is at height h above the earth, and
its radius is r. All dimensions are in cen-
timeters, and the logarithm is basee.
Note that the capacity is proportional
to the wire length L, not to the loga-
rithm of L as Tesla asserted.47 Using
the well-known formula for capacitive
reactance X =/(p f C), where f is the
operating frequency, we could in prin-
ciple obtain the impedance between the
wire and earth. Dividing the voltage of
the antenna, with respect to the earth,
Fig. 11. Tesla denies there is “Space Wave” transmissio n in wireless telegraphy. (True Wireless, Fig. 1 5)
Volume 30, 2017 17
by this impedance, we might think we
have obtained the current on the earth.
But what voltage are we to use?
Because the antenna illuminates the
earth with an electromagnetic wave, the
concept of voltage dierence or poten-
tial dierence cannot be applied. It was
known in the late th century that elec-
tric potential dierence between two
points is calculated by the line integral
of the electric eld along a path between
those points. When there is a time vary
ing electromagnetic eld between these
points the result will depend on the
path taken and so the concept of voltage
dierence ceases to be of use.48
Note that Tesla skirts entirely the
phenomenon of airplane-to-airplane
wireless communication, which had
been observed during the war.49 Such
communication could not possibly
involve earth currents if the transmis-
sion took place over a desert or dry
sandy soil.
The Hertzian Wave Discourse
e publication of Maxwell’s Treatise
on Electricity and Magnetism in ,
which described his work of the pre-
vious decade, together with Hertz’s
experiments of –, created the
paradigm shi which Tesla was unable
to accept. We might be a little indul-
gent here—the new paradigm was slow
to be accepted—consider Marconi for
By the late 
century Marconi
was being lionized in the British press
because of his demonstrations of wire-
less telegraphy, but an interview in
McClure’s magazine from  has him
declining to say what sort of waves he
was using: “What kind of waves they
were Marconi did not pretend to say; it
was enough for him that they did their
business well.”
When asked about the
dierence between his waves and those
used by Hertz he replied “I don’t know.
I am not a scientist, but I doubt if any
scientist can tell you...”
What seemed
to impede the connection of Marconi’s
waves to those of Hertz’s was that it
was known by  that the former’s
radiation could pass through the walls
of a building while Hertz’s, which was
based on a model of radiation as visible
light, would apparently not perform
such a feat.52
Marconi’s first British patent,
number , which was filed in
, speaks of an arrangement that
he calls “a Hertz radiator” producing
eects “which propagate through space
[as] Hertzian rays.” But he also talks
of electrical actions or manifestations
…transmitted through the air, earth,
or water by means of electrical oscilla-
tions of high frequency.” For a while,
Marconi’s manifestations in the ether
were known in some circles as Marconi
waves, but the term soon died. Some
further indication of the confusion,
circa, is a question raised by the
historian of early wireless, J. J. Fahie,
in his publication of , “… is the
Marconi eect under all circumstances
truly Hertzian…?” 53
Aer , we nd that Marconi
began to refer more frequently in his
work to “Hertzian waves.” In a speech
given before the Institution of Elec-
trical Engineers (now the IET) in
18 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
England on March, , he says, “I
think it desirable to bring before you
some observations and results I have
obtained with a system of Hertzian
wave telegraphy, which was the rst
with which I worked….”54 His U.S. pat-
ent , of  refers to “a trans-
mitter producing Hertz oscillations.”
And, following Kuhn, we can say that
Hertzian waves entered the discourse
of “normal science” because we nd
extensive references to them in a text-
book, e.g., Poincaré, cited above. In fact,
studying the index of Poincaré, we nd
that he uses Hertzian waves and elec-
tromagnetic waves as synonyms. John
Ambrose Fleming, who was the rst
Professor of Electrical Engineering at
University College, London, and who
did major work for Marconi beginning
in , published a textbook titled
Hertzian Wave Wireless Telegraphy in
, in which there is not the slightest
doubt that wireless telegraphy relies on
the waves of the title.
Interestingly, Tesla, in certain of
his turn-of-the-century U.S. wire-
less patents, refers to Hertzian waves,
or “radiations,” being “brought into
prominence” by Heinrich Hertz.55 In
all of these instances, such waves are
disparaged as being of an outmoded
or less desirable way of transmitting
signals, or energy, which should be
discarded in favor of one that either
uses extremely strong electric elds
and high antennas to ionize a layer
of the earth’s atmosphere which is
to then act as a conductor of a trans-
mission system (which includes the
earth’s crust)—or of another that uses
wavelengths so long as to make the
earth into a conducting sphere that has
been brought to a resonant condition.
In the later case, he recommends using
frequencies lower than , cycles
per second (cps) and asserts one might
go as low as  cps (patent ,, lines
Maxwell and Einstein: Diculties
fo r Tesla
When Tesla wrote his True Wireless
paper he was not a young man—he
was . Male life expectancy in the
United States was then . His formal
education in science and engineering
had taken place many years before. He
had studied for somewhat less than
three years at the Austrian Polytech
in Graz Austria in the late ’s. In
 he audited courses at Charles Fer-
dinand University in Prague but was
not enrolled. His course work should
have given him a solid grounding in
electric circuit theory, and it was in
school that he developed a great inter-
est in alternating currents, especially
for motors.56 It is highly unlikely that
Tesla would have studied Maxwell’s
theory while at school. As rst pre-
sented in , it was so dicult that
few could understand it; nowhere will
you nd in Maxwell’s treatise the four
succinct equations studied today by
all electrical engineering and physics
students. His analysis is based entirely
on potentials, not the electric and mag-
netic elds used now. He used  equa-
tions and  variables, and it was only
through the eorts of such people as
Hertz, Heaviside, and Willard Gibbs
Volume 30, 2017 19
in the late nineteenth century that the
equations were to assume the form we
nd them in today.
Even with their
simplications, we know that Maxwell’s
theory was not systematically taught
at Cambridge University until aer
around .
Because Hertz’s famous
experiment was inspired by Maxwell’s
work, which Tesla most likely did not
understand, it seems plausible that
Tesla might cling to an electric circuit
theory paradigm in explaining what
was called wireless communication.
Note however, this was not canonical
circuit theory—Tesla had added some
bizarre features of his own to force it
to explain wireless telegraphy.
Maxwell’s theory and its experi-
mental verication by Hertz is not the
only paradigm shi in Tesla’s era that
he was unwilling to accept and under-
stand. roughout his life, he spoke
oen of particles that moved faster
than light—a direct contradiction of
Einstein’s theory of relativity.
In an
interview with Time magazine on the
occasion of his 
birthday in ,
he claimed to have “split atoms” with
no release of energy—again a contra-
diction of relativity. He also asserted
that he had, using “pure mathematics,”
come up with a theory that “tend[s] to
disprove the Einstein theory.” ere
is no indication that Tesla ever had
the knowledge to derive a competing
Circa, Tesla wrote a poem for
his friend George Sylvester Viereck in
which he muses about science.
stanza addresses Newton and contains
these lines:
“Too bad, Sir Isaac, they dimmed your
And turned your great science upside
Now a long haired crank, Einstein by
Puts on your high teaching all the
Says: matter and force are transmutable
And wrong the laws you thought
Note the “long haired crank”—Tes-
la’s name for the man who overthrew
the Newtonian paradigm of mechanics.
Much has been written about oppo-
sition to Einstein’s theory of relativity;
this hostility reached its peak in the two
decades following the conrmation of
the general theory of relativity via the
measurement of the bending of starlight
by the sun’s gravitational eld in .
Some of this opposition was rooted in
anti-Semitism, as the preceding refer-
ence shows, and we do know that Tesla
had anti-Jewish tendencies.62 In addi-
tion, Hertz, whom he diminishes, was,
like Einstein, of Jewish origin,—only
partly in Hertz’s case—but it seems
more likely that the statement to Time
magazine derives more from an almost
pathological narcissism that compelled
him to be in the public eye.
Tesla has been called a scientist,
engineer, and inventor. While the
confusion and angst that can befall a
scientic community having diculty
in adapting to a paradigm shi has
been much written about, especially
aer Kuhn’s seminal publication, the
eect of a scientic paradigm shi on
20 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
inventors, as opposed to scientists, has
been less explored.
When we study the
lives of individual inventors or engi-
neers we can nd failure to adapt to a
paradigm change.
Shifting Paradigms in Invention
Besides Tesla, whose inability to absorb
a new paradigm should be evident, we
have the example of yet another great
inventor, omas A. Edison. Edison
had little formal teaching in schools
and was largely educated by his mother
and by his own readings. His first
important work experiences and inven-
tions were in the eld of the [wired]
telegraph, which operates using direct
currents, and it is clear that he obtained
a strong intuitive grasp of DC theory. It
is understandable that his subsequent
system of generating and distributing
electric power was all based on DC.
Paul Israel, the esteemed biographer
of Edison and editor of the omas
Edison papers, remarks, “While experi-
menting with generators, Edison again
relied on his experience with telegraph
technology to provide a useful anal-
ogy that guided laboratory research.”
Israel points out how Edison and his
workers sometimes envisioned direct
current generators as “carbon battery
Historians have written about
Edison’s unwillingness to adapt to the
newly introduced system of AC electric
power, which posed a direct economic
threat to his own DC system.
will probably never know for sure if
his objection to AC was truly based
on his concern that it was more lethal
than DC, or whether he was acting out
of pride, inertia, economic self-interest,
or an inability to grasp a phenomenon
requiring some mathematical sophisti-
cation that eluded him. His statement in
 to Henry Villard, President of Edi-
son GE, “e use of alternating current
instead of direct current is unworthy
of practical men,” has proved to be as
fatuous as Tesla’s notion that Hertzian
wave theory is “an aberration of the
scientic mind.”66
Age and Vanity
We are le to wonder why Tesla wrote
this long paper displaying a wealth of
ignorance. One clue might come from
an article about him that appeared in
the New York Times of January , ,
a few days aer the inventor’s death. e
generally admiring piece observes, “His
practical achievements were limited to
the short period that began in  and
ended in . And what achievements
they were.” By , Tesla’s last impor-
tant work had taken place more than
half a generation before. Studying a list
of Tesla’s patents, we nd that about
% of them were led on or before
, and all of his important ones were
granted before this date.67
Resurrecting Tesla’s Reputation
His Electrical Experimenter piece can be
read as a rather sad eort to resurrect
his reputation. Moreover, his denigra-
tion of Hertzian waves and promotion
of the primacy of earth currents may be
seen as an attempt to preserve respect
for his construction of a -foot tower
(capped with a sphere) in – on
Volume 30, 2017 21
Shoreham, Long Island, whose pur-
pose was to produce a “World Wire-
less System” that would radiate “several
thousands of horsepower” and permit
the connectedness of all the telephone
and telegraph exchanges in the world
by wireless means. e system was to
use currents in the earth but was never
Consider his allusion in “e True
Wireless” to a speech he gave in 
at the Franklin Institute where there
is a portion entitled “Electrical Reso-
nance.” He remarks in , “is little
salvage from the wreck has earned me
the title of ‘Father of Wireless’ from
many well-disposed workers …” Perus-
ing the speech, we wonder who these
well-disposed workers are.
In his Institute lecture he asserted,
“I do rmly believe that it is practi-
cable to disturb by means of powerful
machines the electrostatic condition
of the earth and thus transmit intel-
ligible signals and perhaps power
We know now that electrical vibration
may be transmitted through a single
conductor. Why then not try to avail
ourselves of the earth for this purpose
[italics added]?”
Notice the use of the
word electrostatic. His proposal is not
based on any use or understanding
of electromagnetic waves. As further
proof of this, he goes on to wonder
what the electrical capacitance of the
earth might be and “the quantity of
electricity the earth contains.” None
of this thinking proved germane to
communication by wireless telegraphy
nor is his obsession in the article with
determining the period of oscillation
of currents that might be induced in a
resonant earth.
Strengthening Tesla’s Claims
In a further attempt to strengthen his
claims to invention in wireless, Tesla
lays claim to discovering the forerun-
ner of the Audion in the caption to his
Fig. (reproduced here as Fig. ). e
captions reads, “e Forerunner of the
Audion—the Most Sensitive Wireless
Detector Known, as described by Tesla
in His Lectures Before the Institution of
Electrical Engineers, London, February,
.” It is instructive to read the text
of the talk where he discusses his “fore-
runner.”70 He begins by paying homage
to Professor Crookes and his invention,
the Crookes tube. Like Crookes, Tesla
is not using thermionic emission. He
employs a cold evacuated glass bulb,
like a lamp bulb, but with no lament.
e bulb, which has a “high vacuum,”
contains some conducting powder,
which in turn is connected by a wire
to one terminal of a high frequency,
high voltage induction coil. e bulb
has a sheet of metal foil on its surface
that is also connected to the coil for
some experiments, but not others. e
Fig. 12. Tesla’s “Forerunner of th e Audion.” (True
Wireless, Fig. 9)
22 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
straight lines that you see in the gure
he calls a “ brush”; it gives o a glow that
he calls luminosity—whose shape and
form he reports is very sensitive to the
presence of objects or nearby electric
or magnetic elds.
However fascinating his demonstra-
tion, Tesla still has not produced the
forerunner of the Audion. e latter, we
recall, was invented by Lee de Forest,
and was the rst working three-element
vacuum tube. His patent application is
dated January , , and it issued on
February , . Despite de Forest’s
confused understanding of his inven-
tion, within the next half dozen years it
was proving its worth as both an ampli-
er and an oscillator. If we want to see
the forerunner of the Audion we must
look to the work of Fleming and Edison,
whose devices, like de Forest’s, relied on
thermionic emission. e distinguished
historian of the vacuum tube, Gerald
Tyne, makes no mention of Tesla in
his well-regarded opus.
is is not
surprising—Tesla’s bulbs responded by
glowing only in the presence of strong,
quasi-electrostatic elds produced by
his machines.
It is regrettable that Tesla’s narcis-
sism caused him to write this paper—it
can only provide diculty for his aco-
lytes and apologists. e ignorance he
displays of classical electromagnetic
theory, which by  was a mature sub-
ject, can only diminish his reputation.
Gernsback and His Magazine
If Tesla’s True Wireless is so utterly
wrong, and if it conicts with the para
digms used by engineers and scientists
of , how did he get his article pub-
lished? To answer this, we must focus
on the magazine where it appeared and
its editor/publisher Hugo Gernsback
Almost a generation
younger than Tesla, Gernsback had
certain things in common with him:
they were both inventors with substan-
tial lists of patents—Gernsback had
, Tesla ; both came from groups
that placed them in small minorities
in the United States (Gernsback was
a Jew from Luxemburg); both studied
science and engineering on the Euro-
pean continent; and both occupied a
kind of nether world bridging science
and fantasy.
ey apparently had a
lasting friendship that would tend to
counter suspicions that Tesla was an
anti-Semite. Gernsback pressured the
Westinghouse Company, which had
benefited greatly from Tesla’s work
in three phase power and induction
motors, to give the near destitute inven-
tor a pension in .74
Gernsback’s Electrical Experimenter
e Electrical Experimenter, started
by Gernsback in , is where we nd
Tesla’s article six years later.75 Although
the term “science ction” did not exist
until coined by Gernsback in , his
magazine Modern Electrics carried a
serialized story of that genre in –,
written by Gernsback—something to
keep in mind when we look at the Elec-
trical Experimenter, where Tesla was to
publish abundantly in the -year life of
that magazine.76
What sort of magazine was the
Electrical Experimenter? It was dense
Volume 30, 2017 23
with ads for radio hardware, e.g., Mur-
dock headphones and audio interstage
transformers as well as Grebe and De
Forest radios. Mainly, it carried stories
of new inventions, especially those with
an electrical basis, such as a new radio
compass, a method of abolishing smoke
electrically, new electric stoves, and
quack medicine—anesthesia via elec-
tricity and an electrical cure for tuber-
culosis using the Tesla coil.77 Much of
the magazine was given over to what we
would now call “techno-euphoria”—a
belief that technology would bring us
wonderful things in the not-too-distant
future. One example was the ought
Recorder, shown in Fig. .
e author of the article is none
other than Gernsback himself. He
imagines a man in an oce who is con
nected to a halo on his forehead. e
halo is supporting an Audion ampli-
er tube that detects and amplies the
man’s thoughts. ey are then sent to an
instrument on his desk that converts his
thoughts to an inscription on a moving
tape. e latter is supplied to the man’s
secretary who is capable of reading the
information on the tape and who can
now write letters or memos based on
what the boss has been thinking. e
article appears in the same issue as
Tesla’s, and Tesla, in an introduction,
gives some measured support to the
idea. Interestingly, Greenleaf Whit-
tier Pickard, a distinguished electrical
engineer who helped develop what we
would now call the crystal radio, circa
, also comments and employs the
term “Hertzian waves,” illustrating how
commonly the phrase was used.
e Electrical Experimenter does
seek to explain legitimate recent
advances in the sciences. For example,
Einstein’s special and general theory
of relativity and the general theory’s
Fig. 13. The “Thought Recorder.” (Electrical Experimenter, May 1919)
24 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
conrmation by the observed bend-
ing of light are carefully described in
the January  issue by an unusual
person for the era: a female astrono-
mer, Isabel M. Lewis, M.A, who was
a regular contributor and the first
woman astronomer to be hired at the
U.S. Naval Observatory.
e magazine
also published pure science ction sto-
ries, such as “At War with the Invisible
appearing in the March and April 
issues, which described a war between
the planets Mars and Earth in the st
Science Fiction, Nostalgia for the Future
Unfortunately, a magazine mixing
techno-euphoria, future studies, sci-
ence ction and real science is play
ing dangerous games: the boundaries
became diuse. e March  Elec-
trical Experimenter has an article by
Gernsback starting on page  entitled
“Can Electricity Destroy Gravitation?”
e author asserts it can, and describes
the work of a Prof. Francis E. Nipher
of the Saint Louis Academy of Science.
e professor’s experiment is described
thusly: He suspends a small lead ball
from a string. It is placed in proximity
to a very heavy lead ball that rests on
a bench. e small ball and string are
seen to be deected toward the heavy
ball because of the force of gravitational
attraction—a straightforward replica-
tion of the famed Cavendish experi-
ment of –.
e professor then
passes a direct current through the
large ball. Nothing has changed. But
then he applies an AC current, et voilà,
the small ball moves away from the
large one, thereby proving that gravity
has been weakened by electricity.
Anyone with a modicum of knowl-
edge of electromagnetic theory would
see what was happening here. e AC
creates a time varying magnetic eld
that induces eddy currents in the small
ball. ese currents interact with the
magnetic eld to push the small ball
away from the large one. e clue that
Faraday’s law of induction and the
induced current serve as the explana-
tion should have been the failure of
the experiment to work with a direct
current. e gravitational eld, like DC
and its resulting elds, is static. A direct
current cannot induce a voltage or cur-
rent in a neighboring circuit, while
alternating currents have that ability.
Eddy currents were well understood by
. One wonders how much real sci-
ence Gernsback knew; it is no surprise
that he permitted another paper based
on dubious physics to be published the
next year: Tesla’s “e True Wireless.”
The Electrical Experimenter
morph ed into another Gernsback
magazine: Science and Invention, in
is publication, although it
did in some ways live up to its title,
increasingly carried science ction and
proved so successful that Gernsback
was able to introduce more magazines
(e.g., Amazing Stories, Wonder Stories)
that were wholly devoted to the science
ction genre, and he is best known as a
publisher of science ction. At least one
historian has suggested that many of
the ideas in Gernsback’s science-ction
stories promoted Tesla’s “still unreal-
ized ideas” for inventions.82
Volume 30, 2017 25
1. Nicholson Ba ker and Margaret Brenta no, “e
World on Sunday: Graphic Art and Joseph
Pulitzer’s Newspaper (1898–1911), (Bullnch
Press, Boston, 2005) pp. 102–103.
2. Nikola Tesla, “The True Wireless,” Elec-
trical Experimenter, vol. 7, no. 3, May
1919, pp.22–23, 61–63, 87. e following
website has images of the original pages:
TrueWireless.pdf. Other sources of the paper
can be found by Googling the search term
“Te sl a Tr ue Wi rel es s.” Vendors of CD’s having
a complete run of the issues of the Electrical
Experimenter can be found on eBay.
3. omas Ku hn, e Struct ure of Scientic Re vo-
lutions, 3rd ed., (Universit y of Chicago Press,
Chicago, 1996).
4. R.P.Feynman, R. B. Leighton, and M. Sands,
“e Feynman Lectures on Physics,vol. 2,”
(Addison-Wesley, Reading, M A, 1964) pp. 1–6 .
5. Jed Buchwald, e Rise of the Wave eory of
Light, (University of Chicago Press, Chicago,
1989); Wit h the birth of qua ntum theor y circa
1900–26, a particle theory of light based on
photons was to ree merge, but it did not under-
mine Ma xwell’s work tha nks to the concept of
the wave-pa rticle dual ity. See for example Ian
Wal msley, Light: A Very Short Introduction,
(Oxford University Press, Oxford, 2015).
6. Hugh Aitken, Syn tony and Spark: e Or igins of
Radio, (Prince ton University Press , Princeton,
1985), Chapter 3.
7. Hugh Aitken, Syntony and Spark.
8. Interestingly, we have only Tesla’s word that
this meeting took place. ere is no support-
ing entry in Heinrich Hertz: Memoirs, Let-
ters, Diaries by Mathilde Hertz and Charles
Süsskind, 2nd edition (San Francisco Press,
San Francisco, 1977). As Tesla was a famous
inventor by the time of the meeting, it is puz-
zling that he was not mentioned by Hertz.
Also, no meeting is described by Bernard W.
Carlson in his denitive biography of Tesla:
Tesla: Inventor of the El ectrical Age, (Pr inceton
University Press, Princeton, 2013).
9. Tom Lewis, Empire of the Air: e Men Who
Made Radio, (Harper-Collins, New York,
1991), p 136.
10. Paul Schubert , e Electric Word: e Rise
of Radio, (Macmillan, London, 1928)
pp.166 –168.
11. It was not unti l 189 3, well aer Tesla had com-
pleted his e ducation, that the g reat simplica-
tion in AC circ uit analysis ma de possible by the
use of complex qu antities bega n to be adopted,
than ks to the work of C. P. Steinmetz. See, for
example , Charles Proteus Ste inmetz, “Comple x
Quantities and their Use in Electrical Engi-
neering,” AIEE Proceedings of International
Electrical Congress, July 1893, pp.33–74.
12. A lf red Hay, e Principles of Alternate Cur-
rent Working, (Biggs and Co, Boston, 1897)
pp.137–148. Available at Google Books;
for other 19th century engineers who used
uid analogies—or rejected them—see Paul
J. Nahin. Oliver Heaviside: Sage in Solitude,
(IEEE Pres s, Hoboken, NJ) 19 88, p. 59 (note his
footnote 3 a nd the derisive comment “drain-
pipe theory”).
13. ere is a stern critique of using mechanical
explanations for explaining electrical phe-
nomena in Henr i Poincaré, Maxwel l’s eory
and Elec trical Oscill ations, (McGraw-Hill, N Y,
190 4) Chapter 1, pp. 1–2. is book i s available
at Google Books. Tesla was so committed to
hydraulic analogies that he supplied one for
his high voltage, high frequency invention,
the Tesla coil. See N. Tesla, My Inventions.
is series of articles originally appeared in
the Electrical Ex perimenter in 1919. ey have
been republished in his book My Inventions
(Barnes and Noble, NY, 1995). See especially
pp. 76–77. e ana logy is so complicat ed that
one is better served by studying the original
electrical device and applying the laws of AC
circuit theory and resonance.
14. Interestingly, in U.S. patent 645,576, Tesla
has not yet discarded the return wire in a
communication/power distribution system
he is proposing. Part of his circuit consists of
a path through an atmospheric layer that his
powerfu l transmitter wil l, he asserts, suc ceed
in ionizing. e ear th is also employed in the
circuit. e patent was granted in 1900, but
by 1919 he has d ispensed with t he return par t
of the circuit.
15. For an explanation of the concept of Whig
history, as it applies to the history of science,
see Steven Weinbe rg, “Eye on the Present, e
Whig History of Science,New York Review
of Books, vol. 62, no. 20, Dec. 17, 2015.
16. J. Zennec k and A. E. Seeli g (tra nslation), Wire-
less Telegraphy, (McGraw-Hill, NY 1915)
26 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
pp.258–259. is book provides an idea of
how textbooks, circa 1910–1920, explained
waves receive d on the far side of the mou ntain.
17. See t he article on d iraction i n the 11th edition
of the Encyclopedia-Britannica, vol. 8, 1911.
/11. Al so, for a modern treatment se e Y. T. Lo,
Y. T and S. W. Lee, Antenna Handbook, (Van
Nostrand-Reinhold, NY, 1988) sec. 29.
18. R. W. P King and S . Prasad, Fundamental Elec-
tromagnetic eory and Applications, (Prentice
Hall, Upper Saddle River, New Jersey 1986)
chapter 7.
19. Jules Stratton, Electromagnetic Theory,
(McGraw-Hill, New York. 1941), secs.
20 . Chen-Pang Yeang, Probing the Sky w ith Radio
Waves (University of C hicago Press, Ch icago.
2013). I am greatly indebted to this source.
21. Henri Poinca ré and F. King Vreeland (trans la-
tion), Maxwell’s eory and Wireless Telegra-
phy, (McGraw-Hill, New York, 1904) p. 161.
Tesla might have countered by asserting that
the Branly coherer responds to the electric
eld—not the magnetic eld—and the earth
weakens the former.
22 . L. W. Austin, “S ome Quantitative E xperiments
in Long Distance Radio Telegraph,” Reprint
No. 159, Bulletin of Bureau of Standards, vol.
7, no. 3, Feb. 1, 1911; see also Robison, 1918,
p. 228.
23. Watson, G. N. e Transmission of Electric
Waves Around the E arth,” Proc Royal Society
(London) Series A, vol. 95, July 15, 1919, pp.
24 . Heinrich Her t z , E lec tr ic Wa ves , (Dover Books,
Mineola NY, reprint of Macmillan book
1893) chapter 8 (dati ng from 1888, e specially
25. Kuhn, page 43.
26. Samuel Robison, Robison’s Manual of Radio
Telegraphy and Telephony for Naval Electri-
cians (U.S. Naval Institute, Annapolis, MD,
1918) p.131. He asserts that the directivity
behavior of the “at top antenna” attributed
to Marconi, which involves a long piece of
wire or wires parallel to the ground, is still
not understood.
27. L. J. Chu, “Grow th of the Anten nas and Propa-
gation Field Bet ween World War 1 a nd World
War 2. Part 1, Antennas,” Proceedings of the
IRE, vol. 50, no. 5, May 1962, pp. 685–7.
28 . Charle s Burrows, “e His tory of Radio Propa-
gation up to the E nd of World War I,” Proceed-
ings of the IRE, vol. 50, no. 5, May 1962, pp.
29. Note that Marconi had described arrays
formed from inverted L antennas as early
as 1906, as noted in G. W. Pierce below. e
horizont al elements were much longer th an the
vertical ones, a conguration not suggested
in Tesla’s Fig. 16. G. W. Pierce, Principles of
Wireless Telegraphy, (McGraw-Hill, New York,
1910) Chapter 25. See also Practical Wireless
Tel egraphy, E lmer Bucher, Wireless Pre ss, 1917,
sec. 233. Here, the horizontal portion of the
antenna is nearly a mile long.
30. See G. Marconi, “On Methods Whereby the
Radiation of Electric Waves May Be Mainly
Conne d to Certain Di rections, and W hereby
the Rece ptivity of a Recei ver May Be Restrict ed
to Electric Waves Emanating from Certain
Directions,”Proceedings of the Royal Society
of London. Series A, Containing Papers of a
Mathematical and Physical Character77.518
(1906): 413–21; Electrician, vol. 60, 1908, p.
31. Pierce, p. 298.
32. Zenneck and Seelig, Sec. 202–204. e book
contain s the reference to Von Hoerschelma nn,
which was published in German a s a disserta-
tion in 1911.
33. Aitken, p. 267.
34. Nahin, pp. 142–143.
35. Be rnard Carl son, Tesla: Inventor of the Elec-
trical Age, (Princeton U. Press, Princeton NJ,
2013) p. 20 0–202 ; note that some images we re
the result of multiple exposures where Tesla
was not present when the sparks were being
generated, see pp. 297–299.
36. T. C. Mart in, editor, e Inventions , Researches
and Writings of Nik ola Tesl a, 1893; republished
by (Barnes and Noble, NY, 1992) Chapter 6.
From the lect ure: “e reason why no pa in in
the body is felt, and no inju rious eect noted,
is that everywhere, if a current be imagined
to ow through the body, the direction of its
ow would be at right angles to the surface;
hence the body of the experimenter oers
an enormous section to the current, and the
density is very small, with the exception of
the arm, perhaps, where the density may be
considerable…e expression of these v iews,
which are t he result of long continue d experi
ment and observation, both with steady and
Volume 30, 2017 27
varying currents, is elicited by the interest
which is at present taken in this subject, and
by the manifestly erroneous ideas which are
dail y propou nded in journal s on this subject.”
Tesla misses t he essential poi nt here—the very
shallow depth of penetration of the energy.
e arm plays no special role. Notice that he
takes a swipe at other workers’ “erroneous
37. Indeed, it was in Poincaré’s book of 19 04 (see
38. E. C. Jordan and K. Balmain, Electromag-
netic Waves and Radiating Systems, 2nd ed.,
(Prentice-Hall. NJ, 1968) p. 655.
39. Note that this is a simplication of a formula
derived by Heav iside in 1888 . See Nahin, who
also g ives the formula we are u sing here, p. 176
4 0. Kin g and Prasad, se ction 5.9. e sinθ var iation
was derived by Hertz in the 19t h century (see
Hertz, El ectric Wave s, p. 143 above) and was
popula rized by Louis C ohen in a paper writ ten
for engine ers in 1914. See his “E lectromagnet ic
Radiation,” Journal of the Franklin Institute,
April 1914, vol. 177, no. 4, pp. 40 9–418.
41. Robison, 1918, p. 62. Notice that the same
picture appears in an even earlier edition of
Robison, dating from 1911, on page 76. is
book is available from Google Books.
42 . R.W.P Ki ng, eory of Line ar Antennas, (Ha r-
vard Universit y Press, Cambr idge, MA, 195 6)
chapter 7. Note that t his work is based in pa rt
on Sommerfeld’s work of 1909.
43. Burrows.
44. Ibid.
45. e ionosphere, although not called by that
name, cou ld be found in elect rical engine ering
handboo ks as early as 1915 ; see for example W.
H. Eccles, Wireless Telegraphy and Telephony:
A Handbook of For mulae, Data and Info rma-
tion. (Electrician, London, 1915), pp. 162–3.
4 6. Eccles, p. 120.
47. In the unlikely event that the wire hangs
stra ight down from the ai rcra, the prec eding
formula doe s not apply. However, it would s till
be incorre ct to say that the cap acitance vari es
with the logarithm of the length of wire. e
required formula shows a more complicated
behavior. See Eccles p. 120.
48. James Clerk Maxwell, A Treatise on Electric-
ity and Magnetism, vol. 1.(Clarendon Press,
Oxford 1891) p. 76.  is has been reprint ed by
Dover Books, NY, 1954. For a modern treat-
ment that emphasizes the limitations of the
concept of voltage dierence see Edward.C.
Jordan and Kenneth. Balmain, Electromag-
netic Waves and Radiating Systems, second
ed., (Prentice-Hall, New Jersey 1968) p. 36.
incombat/ See also R . W. Burn s, Communica-
tions: An Inte rnational His tory of the Formative
Years, (IEE Press, UK, 2004) p. 407.
McClure’s Magazine, (London), June 1899,
pp. 99 –112.
51. Su ngook Hong, Wireless: From Marconi’s Black
Box to the Audion, (MIT Press, Cambridge,
MA, 2001) p. 20 5. See Aitken, h is footnote 12
page 195 . Note (same p age) th at even Fleming,
Marconi ’s wel l-rega rded consultin g engineer,
was at rst misled by the misuse of analogies
drawn from the theory of light.
52 . Aitken, pp. 28 5–286 and Hong p. 42, foot note
53. J. J Fahie, A History of Wireless Telegraphy,
(Blackwood, Edinburgh, 19 01) p. 216.
54. Guglielmo Marconi, “Wireless Telegraphy,”
Journal of the Institution of Electrical Engi-
neers, vol. 28, 1899, pp. 273 –291.
55. U.S. Patent 685 ,955 of 1901, 685,95 4 of 1901,
685,956 of 1901, 787,412 of 1905.
56. Carlson, chapter 2.
57. Nahin, chapters 7 and 9.
58. Bruce Hunt, e Maxwellians, (Cornell U.
Press, Ithaca, NY, 1991) p. 202.
59. Marc S eifer, Wizard: e Life and Times of
Nikola Tesla, (Citadel Press. New York, 19 98)
p. 423.
60 . Margaret Chene y & Robert Uth, Tesla: Master
of Lightning , (Barnes and Noble/Me tro Books,
NY, 2001) pp. 138 –139.
61. Milena Wazeck , Einstein’s Opponents, e
Public Con troversy about the e ory of Relativ-
ity in the 1920’s. (Cambrid ge University Pres s,
Cambridge, UK, 2014).
62. Seifer, p. 212.
63. For an example of writing on the subject of
paradigm shis in physics aer Kuhn, see
Jaume Navarro, “Electron Diraction Chez
omson: Ea rly Responses to Qua ntum Phys-
ics in Brit ain.” e British Journa l for the His-
tory of Science, vol. 43, 2010, pp. 245 –275.
64. Paul Israel, Edison: A Life of Invention, (John
Wiley & Sons, New York, 1998) p. 176.
65. omas Parke Hughes, Networks of Power:
Electr ication in Western S ociety, (Johns Hop
kins University Press, Baltimore, 1983).
28 e AWA Review
Paradigm Lost: Nikola Tesla’s True Wireless
66. Matthew Josephson, Edison: A Biography,
(Wiley, New York, 1992) p. 359.
67. e web site
List_of_Nikola_Tesla_patents l ists 111 or 11 2
U.S. Tesla patents (dependi ng on how they are
68. Nikola Tesla, “My Inventions,” Electrical
Ex perim enter, 1919, see chapter 5, avai lable on
the Internet http://www.teslasautobiography
.com/ See also Carlson, chapter 15.
69. T. C. Martin, pp. 346–7. In the late 19th cen-
tury, Tesla sp oke repeatedly of disturbing the
electrostatic cond ition of the eart h as a means
of sending i ntelligence. Se e also Mart in p. 292
for an example used in a speech before the
British IEE in 1892.
70. is tube appears in a speech he gave in 1892
to the Ins titution of Elect rical Engi neers (Lon-
don). See T. C. Martin ed. pp. 225–229.
71. Gera ld Tyne, Saga of the Vacuum Tube,
(Antique Electronic Supply, Tempe AZ.
72. Mike Adams, “Hugo Gernsback: Predicting
Radio Broadcasting, 1919–1924,” Antique
Wireless Association Review, vol. 27, August
2014, pp. 165 –192 .
73. For a list ing of the Tesla U.S. patents see htt p://
html. e number for Gernsb ack was obtained
from a sea rch of Google Patents usi ng his name
as the inventor. Footnote 64 above also gives
a source of Tesla’s patents.
74. Carlson, p. 379.
75. K. Massie, and Stephen Perry, “Hugo Gerns-
back and Radio Magazines: An Inuential
Intersec tion in Broadcast H istory,” Journal of
Radio Studies, vol. 9, no. 2 , 2002 . Note that the
magazine was originally titled e Electrical
Experimenter. e title was shortened during
76. e term was apparently rst used in Gerns-
back ’s maga zine Wonder Stories i n the issue of
June 1929; Gernsback had earlier coined the
term “scient iction.” See Leon St over, Science
Fiction from Wells to Heinlein, (McFarland
Publishers, Jeerson, NC, 2002) p. 9.
77. Frederick Strong, “e Home Treatment of
Tuberculosis by High Frequency Currents,”
e Elect rical Exper imenter, vol. 5, no. 10, Feb.
78. ht tp://maia.u sno.nav /women_ hist ory/
79. M Ashley and R. Lowndes, e Gernsback
Days, (Wildside Press, Rockville, MD, 200 4)
p. 51–2.
81. Ashley, above, p. 53.
82. Stover, p. 175. In 1923 Gernsback produced a
book, Radio for All, published by Lippincott.
e work was designed to introduce people
to what was st ill in many ways a hobby. us,
there were instructions for building simple
radios—crystal and one-or two-tube sets, as
well as t ransmitters . It is pu zzling that t he book
makes no mention of the work of Tesla, given
his fr iendship with Ger nsback, althou gh there
are numerous allusions to Marconi as well as
single refe rences to such inventors as Poulsen,
Pickard, Fessenden, and Dunwoody.
I would like to thank Dr. Elizabeth
Bruton of the University of Manches-
ter, Jodrell Bank Discovery Centre, for
reading this paper and oering useful
advice. And I would also like to thank
Prof. Karl Stephan of Texas State Uni-
versity, San Marcos, for giving me a
valuable library of early textbooks on
wireless telegraphy. I would like to
thank Prof. Chen-Pang Yeang of the
University of Toronto, a distinguished
historian of early th-century wave
propagation theory, for his comments.
I am indebted to this journal’s editor
Dr.Eric Wenaas for many useful sug-
gestions that resulted in my paring
down this paper and making it clearer.
About the Author
A. David Wunsch was born in Brook-
lyn, NY, on December , . He grew
up in the same Flatbush neighborhood
of red diaper babies as Bernie Sanders.
David studied electrical engineering at
Cornell and later earned his Ph.D. at
Volume 30, 2017 29
Harvard where he was a student in the
Antenna Group directed by Professor
R.W.P. King.
David has spent most of his pro-
fessional life at the University of Mas-
sachusetts, Lowell which is located in
Lowell, Massachusetts. He is now Pro-
fessor of Electrical Engineering Emeri-
tus. In  he started the course for
liberal arts majors at Lowell, Principles
and History of Radio. It is described in
the article “Electrical engineering for
the liberal arts: radio and its history,”
IEEE Transactions on Education, vol.,
no., pp.–, Nov .
David is the book review editor of
the IEEE Magazine Technology and
Society. He is the author of two text-
books: Complex Variables with Appli-
cations (Pearson), currently in its third
edition, and the recently published A
MATLAB Companion to Complex Vari-
ables (Taylor and Francis).
David recently rebuilt the Heathkit
oscilloscope that he constructed in .
He thought it would make him  again
but his beard remains white.
David Wunsch