Jean-Antoine Nollet The first wireless Network

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Transcript Jean-Antoine Nollet The first wireless Network

The Telegraph:
The Victorian Internet
Jean-Antoine Nollet
The first wireless Network
Nollet’s Experiments
• As Abbot of the Grand Convent of the
Carthusians in Paris, Nollet decided to test his
theory that electricity traveled far and fast.
Nollet’s Experiment
• On a spring day in 1746, Nollet sent 200 of his
monks out in a line 1 mile long. Between each
pair of monks was a 25-foot iron wire. Once the
reverend fathers were properly aligned, Nollet
hooked up a battery to the end of the line.
Nollet’s Experiment
• As the electric charge surged through the
line of monks, all started swearing,
contorting, or otherwise reacting
simultaneously to the shock. The electrical
signal had traveled nearly a mile and it
appeared to have done so “instantly”.
Electricity and Nollet
To impress King Louis XV, Nollet discharged a
Leyden jar in front of at Versailles by sending
current through a chain of 180 Royal Guards,
causing them all to jump in the air together
Electrified Men
Women were suspected as being likely to arrest or
deflect the longitudinal surge of the electricity. In
one experimental line of electrified men, the
current came repeatedly to a standstill at the
same person, whose manhood came as a result
into embarrassing question. His reputation was
only restored when experiments on accredited
castrati failed to show any difference in their
conductivities. The maligned man had in fact
been standing in a puddle which had
discharged the current
Wireless Communication
Popular in the early 19th century was the
heliograph, which was invented in 1810 by the
German mathematician Carl Friedrich Gauss.
The heliograph sported two mirrors that could be
tilted by an operator to point in just the right
The Occulting Telegraph
• Babbage entered the optical
communications arena in 1851 with a plan
for a light-flashing machine that he named
the "occulting telegraph." This is how
Babbage described his device:
"I then, by means of a small piece of clockwork and a lamp, made a numerical system of
occultation, by which any number might be
transmitted to all those within sight of the
source of light."
Heliographs in Practice
Upon receiving a description of Babbage's contraption,
the U.S. Congress appropriated $5,000 -- a considerable
sum at the time -- for occulting-telegraph experiments.
It's not clear what the outcome of the experiments was,
but a several decades later the American army started
using machines to transmit data across beams of light,
most notably heliographs.
In 1886, Nelson Miles, the general perhaps best known
for his capture of Geronimo, used a network of
heliographs to transmit messages to his troops while
fighting various Native American tribes. His network
comprised 27 signaling stations in Arizona, placed 25 to
30 miles apart.
Miles Heliograph Network
Records from that time indicate that between May 1,
1886, and September 30, 1886, a total of 2,276
messages containing 80,012 words were transmitted
over the network. The average speed of the system was
reportedly 16 words per minute, or roughly 10 bits per
second. Clearly, the technology rewarded those who
could express themselves succinctly.
The Native Americans, of course, had their own opticaltransmission system, which dated back further still. Most
likely, the data rates achieved with smoke signaling
could have rivaled those of Miles's network.
The 18th Century and Beyond
It is hard to imagine what daily life must have been like two centuries ago,
without radios, movies, telephones, or electricity. The streets in the larger
cities were lit by candles. In New York, for example, a city ordinance had
been in effect since 1697
. . . that the lights be hung out in the darke time of the moon within this citty,
and for the use of the inhabitants; and that every 7th house doe hang out a
lanthorn and a candle in it.
Mail was delivered by stagecoach in the United States, and by merchant
vessels and mounted couriers throughout most of Europe. A letter or
newspaper took only a few days to travel from London to Stockholm, and to
get a piece of mail delivered within one of the larger cities took just hours. It
was not unusual to extend a dinner invitation by regular mail in the morning,
and to receive the response well in time to make the final preparations for
that day.
The First Telegraphs
In September 1794, Abraham Niclas Edelcrantz, a Swedish nobleman and scholar,
sits in his library in the center of Stockholm, in front of a large fireplace. He is reading
Gentleman's Magazine
Edelcrantz Learns of Chappe’s
The September 1794 issue of this journal contained a report on a new
French contraption that caught Edelcrantz's attention. This is, in part,
what Edelcrantz read
. . . a method to acquaint people at a great distance, and in very little time,
with whatever one pleased. This method is as follows: let persons be placed in
several stations, at such distances from each other, that, by the help of a telescope, a
man in one station may see a signal made by the next before him; he
immediately repeats this signal, which is again repeated through all the intermediate
stations. This, with considerable improvements, has been adopted by the French,and
denominated a Telegraphe; and, from the utility of the invention,we doubt not but it
will be soon introduced in this country. (Britain)
The invention was attributed to Claude Chappe.
Chappe Semaphore Network
Early Experiments
Claude Chappe, born in 1763, Grandson of a French Baron, trained
for the church. He lost his religious benefices in the wake of the
French revolution in 1783 and decided to work with his brothers on
the problem of the optical telegraph.
Synchronized System
Early Chappe Experiments
The Synchronized System (1791)
“The first telegraphic correspondence
that we performed was done with two
pendulum clocks, that were kept in perfect
synchrony; the face of the clocks was divided into ten
parts, each part designating a different numeral When
the pointer of one clock passed over the number one
wanted to indicate, a sound was made, announcing to
the receiver that the number which also his pointer
indicated at the moment that the sound was heard, was
significant. By representing the words in a dictionary
with successive numbers one could thus transmit any
thought. ..." .
The Panel Telegraph
• The Panel Telegraph (1792)
• Rectangular wooden frame with five sliding
panels that could be displayed or obscured via
pulleys. A 5-bit binary code (32 combinations)
was used .
A system very similar
to this was
by the British
and the
The Semaphore Telegraph
• Horizontal beam (called the "regulator") +
two smaller wing beams (called the
"indicators"), could be varied in 45 degree
Funding !!
• The National Assembly of France voted
6000 francs to Chappe to build the
system. This was the first recorded use of
the term telegraph = "far writing."
References to word Telegraph
"The capitals of distant nations might be united
by chains of posts, and, the settling of those
disputes which at present take up months or
years might then be accomplished in as many
hours. An establishment of telegraphs might
then be made like that of the post; and instead of
being an expence, it would produce a revenue."
• Encyclopaedia Britannica, 1797, in the first entry
on the telegraph.
Optical Telegraphy in Europe
Edelcrantz began experimenting with his own optical telegraph designs
the month that he read the article about Chappe Within two months he
was able to demonstrate a first working version. Edelcrantz's first design
still looked much like Chappe's, with articulated arms and flaps.
Edelcrantz would later, after many experiments, switch to a shutter
telegraph design that is similar to one of the first designs that Chappe
had used in 1791 and 1792 and later abandoned.
There is no indication that Edelcrantz knew about these earlier
experiments of Claude Chappe at this time.Why Chappe rejected the
shutter principle and replaced it with semaphore arms, and Edelcrantz
rejected the semaphore arms and replaced it with shutters is a mystery.
Both designs were quite successful, and received much following. For
almost half a century, optical telegraphs became part of the landscape
in Europe.
The Optical Telegraph in Society
Optical telegraphs can be spotted in the
background of many paintings from the period.
Victor Hugo (1802-1885), at age 17, wrote a
poem, Le Télégraphe, and it may be the first
appearance of a reference to the telegraph in
"This cursed telegraph, will it finally cease To
importune my eyes which it starts to weary? There, in
front of my attic window, it sits quite ridiculous They
place a telegraph near my cell! It rises, it drops, and
In these vain movements my inattentive spirit some
secrecy seeks..." Le Télégraphe.(1819),
Telegraphs and Church Towers
The telegraph to which the poem refers is
that of the Saint-Sulpice church, whose
architectural style Hugo despised
Count of Monte Christo:
The Telegraph
In A. Dumas’ The Count of Monte Cristo (1844)
we find (Chapter 60: The Telegraph):
“ the light of the sun its black arms, bending in every direction, always reminded
me of the claws of an immense beetle, and I assure you it was never without emotion
that I gazed on it, for I could not help thinking how wonderful it was that these various
signs should be made to cleave the air with such precision as to convey to the
distance of three hundred leagues the ideas and wishes of a man sitting at a table at
one end of the line to another man similarly placed at the opposite extremity, and all
this effected by a simple act of volition on the part of the sender of the message. I
began to think of genii, sylphs, gnomes, in short, of all the ministers of the occult
sciences, until I laughed aloud at the freaks of my own imagination
The Evolution to the Wired
The optical system of towers, telescopes,
and various signaling devices spread
across Europe so that by the mid 1830's
there were almost 1000 telegraph towers
in a half-dozen countries. But, the optical
telegraphs suffered from many drawbacks,
not the least of them being rain, mist, and
darkness, all fairly frequent occurrences
in much of Europe.
Morse’s Idea
The idea of an electrical telegraph was bandied about by many, but
it was often put in the same category as perpetual motion machine.
In 1832, Samuel B. Morse, a painter, was on a ship back from
Europe when he caught the telegraph bug. Seven years earlier, he
had been traveling to Washington, D.C. to do Lafayette's portrait and
had received a letter that his wife had died. He raced back home,
but the letter took so long in transit that he missed her funeral. That
experience marked him, and the idea of an electric telegraph hit
Morse got off the boat from Europe with the sketches for an electric
telegraph in hand and the beginnings of the Morse code already
Morse’s Implementation
• Morse in the United States and Cooke and
Wheatstone in England met with many skeptics, but
finally in 1844 Morse got his line up and running
between Washington and Baltimore and transmitted
his first message:
"What Hath God Wrought?"
“Surely there is no enchantment against Jacob, neither is there any
divination against Israel: according to this time it shall be said of Jacob
and of Israel, What hath God wrought! “ Numbers 23: 23 (KJV)
Morse Makes News
• New York Herald, on the occasion of the test
between Washington, D.C. and Baltimore:
Professor Morse's telegraph is not only an era in the
transmission of intelligence, but it has originated in the mind an
entirely new class of ideas, a new species of consciousness.
Never before was any one conscious that he knew with certainty
what events were at that moment passing in a distant city—40,
100, or 500 miles off. For example, it is now precisely 11 o'clock.
The telegraph announces as follows:— "11 o'clock—Senator
Walker is now replying to Mr. Butler upon the adoption of the
'two-third' rule." It requires no small intellectual effort to realize
that this is a fact that now is, and not one that has been.
Baltimore is 40 miles from Washington. It is a most wonderful
achievement in the arts.
The Morse Telegraph Proliferates
The new medium took off like wildfire. By
1850, there were over 12,000 miles of
telegraph lines in the United States. The
lines quickly circled the world, creating a
global network and global industries.
The Telegraph “Business”
• Most telegraphs were sent to a SnailMail® address. The
telegraph network would transmit it to the nearest post
office (in Europe) or telegraph company office (in the
U.S.) and a messenger would take it to the final
• The problem with postal addresses was that they
chewed bandwidth. In Britain, somebody had the idea of
coming up with a new addressing system, based on
nicknames. Instead of chewing up valuable bits on the
line (and paying for those bits by the word), people could
refer to a destination by a registered nickname. These
nicknames were quite popular, with over 35,000 being
registered, yielding a substantial profit for the postal
system, the monopoly provider of the namespace.
Precursor of the Internet
The telegraph spawned much of our modern age. One
inventor trying to squeeze more capacity out of telegraph
lines was Alexander Graham Bell, who was working on a
harmonic telegraph, one that would send several signals
simultaneously at different pitches.
When his assistant plucked a reed too hard at one end
of the line, Graham heard more than a signal: he heard
the unmistakable sounds of the reed itself and realized
that the electrical lines could transmit voices. His
telephone invention grew even faster than the telegraph;
over 30,000 phones were in operation 3 years after the
first service began.
One young telegraph operator, Thomas
Edison, soon turned from fiddling with new
hacks on telegraph equipment to
electricity, moving on to start the first
systematic commercial electrical
distribution systems.
With the rapid growth of telephone technology,
those who had “expertise” in the use of the
Morse code soon discovered that their
“technological skills” were little needed… the
prized positions as telegraph operator soon
became those of the unemployed… and the face
of technology moved on without them.
@ The internet would be the next new wave