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07.07
Heinrich Hertz (1857 –
1894)
The Man and His Pivotal Role in Technology
By John Vardalas
The electromagnetic spectrum,
and its commercial exploitation, today seems as
commonplace as the air that surrounds us. And
yet, there was a time, in the not too distant
past, when the very concept of the
electromagnetic spectrum was unknown. In the
1860s, in a series of papers, James Clerk
Maxwell first laid out his theory of the
electromagnetic field. Then, in 1873, Maxwell
produced his well-known, two-volume Treatise
on Electricity and Magnetism. Far from being an
instant success, it took almost two decades
before “Maxwell’s Laws” gained widespread
acceptance within the scientific and engineering
establishments. The key that unlocked the door
to universal acceptance was Heinrich Hertz. His
elegant experiments transformed contested theory
into an accepted model of reality. On the 150th
anniversary of Hertz’s birth, it is fitting that
we reflect briefly upon the man, and his role in
setting the stage for the profound technological
applications that would emerge from the
electromagnetic field concept.
When Hertz began his experiments
on electrodynamics in 1886, little was known
about Maxwell’s ideas on the continent of
Europe, where Newtonian action-at-a-distance was
still the only paradigm for understanding
electrical and magnetic phenomena. By the end of
the decade, Hertz’s validation of Maxwell’s
electromagnetic field theory had forced a
conceptual revolution within the European
community of theoretical physicists. Hertz had
shown that rather than being instantaneous,
electromagnetic effects propagated at a finite
speed. An even more astounding result from
Hertz’s experiments was the discovery of radio
waves and the realization that they behaved like
light. In Maxwell’s homeland, the British Isles,
the impact of Hertz’s experiments was equally
dramatic, but opposition was from a different
quarter.
Unlike the situation in
continental Europe, Maxwell’s work in
electricity and magnetism developed a very
strong following among the theoretical
physicists on the western side of the Channel.
Maxwell himself had not actively sought to
create a school around his theory. But a small
number of theoreticians scattered throughout
Britain and Ireland were immediately taken by
Maxwell’s reconceptualization of electricity and
magnetism. Men like George Fitzgerald, Oliver
Heaviside, Oliver Lodge, William Thomson, John
Poynting and Silvanus Thompson took it upon
themselves to refine, expand on, and champion
Maxwell’s theory. Thus, before Hertz even
started his experiments on electrodynamics,
Maxwell’s theory had already gained a strong
theoretical foothold in the British Isles. But
not all in Britain accepted Maxwell’s notions.
Most electrical engineers were very mistrustful
of Maxwell’s theory of electrodynamics. Like
Edison and the others who had developed
electrical technology to this point, they saw
themselves as “practical men” and they could not
see any value in the complex, mathematical
theories advanced by the Maxwellians. In the
eyes of these practical men, the Maxwellians
were more interested in abstract formalism than
in hard reality. Sir William Preece exemplified
the “practical” man’s disdain of theory.
As one of the most prominent
electricians of the day, William Preece held
considerable sway in the halls of industry and
government. Preece had not had any formal
training in electricity and magnetism when he
joined the Electric Telegraph Co. Learning by
doing, he rose up in the company. When the
British government put all telegraphy under the
control of the Post Office, Preece was named its
Chief Electrician. Bruce Hunt, an historian of
Physics, reminds us that Preece, like many of
his countrymen of the day, was deeply
mistrustful of theoretical abstractions.
Experience, not theory, was the key to teasing
out the technological opportunities in nature.
Born in 1834, fifteen years before
most of the Maxwellians, Preece saw these
theoreticians as young upstarts who had little
respect for the experience acquired by their
elders. The scientific and technical arguments
between Preece and the Maxwellians were often
acrimonious. There was disdain on both sides.
The Maxwellians greeted the news
of Hertz’s experiments with great jubilation.
Having put their theoretical abstractions on the
bedrock of reality, Hertz’s results undercut the
central objection raised by practical men like
Preece. The Maxwellians had themselves looked
for empirical evidence but were unsuccessful. So
it is ironic that the prize would go to a man
from Europe where Maxwell’s ideas were
relatively unknown. The generational debate
between Britain’s older practical electrical
engineers and its younger theoretical physicists
would soon end. Not necessarily because the
older generation acquiesced, but rather because
they died off and were eventually replaced by
the first generation of academically trained
electrical engineers who were now well-versed in
Maxwell’s mathematical theory.
By the early 1890s, Hertz’s work
had won universal acclaim. Then in his
mid-thirties, with a brilliant future and fame
assured, Hertz had to face death. In 1892, he
was diagnosed with a head cold and then with an
allergy, his condition progressively
deteriorated. His body had been invaded by
stubborn infections. Then he succumbed to blood
poisoning. For nearly two years, he suffered
through debilitating poor health. His spirits
must have been very low and yet he always
remained a playful father with his children.
Fearing that the end was near, he was determined
to finish his treatise on mechanics. He faced
death with courage, humility and a sense
of duty. “Nothing is harder,” he wrote, “than a
struggle fought no longer for victory, but
merely so as not to give up without making a
decent stand.” There was also a calm acceptance.
Three weeks before his death on 1 January 1894,
he wrote to his parents:
“If anything should befall me,
you are not to mourn; rather, you must be a
little proud and consider that I among the
especially elect destined to live for only a
short time and yet to live enough. I did not
desire or choose this fate, but since it has
overtaken me, I must be content; and if the
choice had been left to me, perhaps I should
have chosen it myself.”
For a more in-depth look at
Hertz’s work and life, the reader should look
at:
Mathilde Hertz and Charles
Susskind (eds.), Heinrich Hertz:
Erinnerungeon, Briefe, Tagebücher/ Memoirs,
Letters, Diaries (second enlarged bilingual
edition), (San Francisco: San Francisco Press,
1977)
J.G. O’Hara and W. Pricha,
Hertz and the Maxwellians, (London: Peter
Peregrinus Ltd. And Science Museum of London,
1987)
Bruce J. Hunt, The
Maxwellians, (Ithaca, NY: Cornell University
Press, 1991)
Jed Buchwald, Creation of
Scientific Effects: Heinrich Hertz and Electric
Waves, (Chicago: University of Chicago
Press, 1994)
Charles Susskind, Heinrich
Hertz: A Short Life, (San Francisco: San
Francisco Press, 1995).

John Vardalas, Ph.D., is an
IEEE Postdoctoral Fellow in the Department of
History at Rutgers University in New Brunswick,
N.J. He can be reached at
todaysengineer@ieee.org. Visit the IEEE
History Center's Web page at:
www.ieee.org/organizations/history_center.
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