Guglielmo Marconi

Today multitudes sneer when they hear that Guglielmo Marconi - quote - "invented the radio" - unquote. I mean, c'mon! That rich uneducated Italian kid? He just put together a bunch of stuff that others had already invented. Oh, he may have tweaked a few odds and ends and made some improvements. But do you call that inventing?

Well, with due respect to all the other people who - quote - "really invented the radio" - unquote - 1) putting previous inventions together to produce a new and useful product is indeed inventing, and 2) improvements of older inventions are new inventions too. Guglielmo Marconi was an inventor.

In fact, many patents of Thomas Edison, Alexander Graham Bell, and Nikola Tesla explicitly state that their inventions were improvements over something earlier. Even these most famous of "real" inventors rarely invented anything out of the blue.

And the idea of "wireless telegraphy", as radio was originally called, was almost as old as telegraphs themselves. As soon as the telegraph companies began stringing the wires, everyone got to thinking how great it would be to dispense with the wires altogether.

At first the term "wireless" wasn't necessarily limited to our modern notion. In 1850, someone known to us only as a Mssr. Benoit claimed you could set up two bowls with the letters of the alphabets printed on the inside. One bowl can be in Paris and the other in New York. Next place snails on the letters. If you touched one snail in Paris and it put out its horns, M. Benoit claimed the snail in New York on the same letter would also put out its horns. So by poking the snails you could send messages across the Atlantic.

Alas, historians do not consider Mssr. Benoit to be the inventor of wireless communication.

Another idea was to use "induction" of the ground or water. Samuel F. B. Morse himself claimed that in 1842 he sent a wireless telegraph message across a river using only the natural conductivity of the water. Whether he really did or didn't is a moot point since nothing practical came out of his experiments.

However a possible air transmission of an electric signal - if not a real message - may have been as early as 1866. This was when Mahlon Loomis, a Washington dentist, sent up two kites on wires from the top of two hills. He drove the wires into the earth and using - as he said - the "natural electricity of the atmosphere" - claimed he sent signals from one kite to another.

This demonstration - whatever it actually was - convinced two congressman, Senator Samuel Pomeroy of Kansas and Congressman John Bingham of Ohio, that the invention was worth pursuing. The congressmen sponsored legislation that would create the Loomis Aerial Telegraph Company and Mahlon also had support from the famous Senator Charles Sumner of Massachusetts. Mahlon got a patent in 1873, and President Hiram Grant signed the bill into law.

The patent, to say the least, is vague. Although you might argue it "anticipates" the idea of using electricity to transmit a signal through the air, there's no indication Dr. Mahlon sent any real messages. In any case, the Looomis Aerial Telegraph Company never got anywhere, and Martin isn't considered the inventor of the wireless either.

Maxwell's Silver Equations

By the late 19th century it was clear that wireless communication was going to use electricity, not snails. So not surprisingly the people who made real progress were the bonafide pioneers in the field of electricity and magnetism.

In the late 18th and early 19th century electricity was produced using batteries. Batteries generate direct current, that is, the current flows constantly in one direction. Direct current from these "voltaic piles" was the basis for most of the early discoveries about electricity.

One of the discoveries was in 1820 when the Danish physicist and chemist Hans Christian Ørsted (also spelled "Oersted") noticed that if you placed a compass needle close to a wire and turned on a current, the needle would move. Additional experiments proved that the current was creating a cylindrical magnetic field around the wire.

With Hans demonstrating that an electric current created a magnetic field, it fell to Michael Faraday to prove that a magnetic field could create current. In 1831 Michael moved a bar magnet in and out of a coil of insulated wire. Using a galvanometer, Michael showed that a current flowed in the wires.

However, you only had current when the magnet was moving. Figuring it would work the other way around, Michael built an apparatus where the edge of a rotating iron disk passed between the poles of a horseshoe magnet. By attaching wires at both the center and the edge of the the disc (using "brush" contacts) Michael generated a direct current. The problem was that the current wasn't that strong and someone had to continually turn the crank. So batteries were still best for producing current. But at least Michael had invented the first electric generator.

Then in 1833 a French inventor, Hippolyte Pixii (pronounced "heep-oh-LEET peeks-EE"), created an electric generator where he rotated a horseshoe magnet underneath two coils of insulated wires. This produced an electric current which was stronger than that from Michael's generator. The problem was the current wasn't steady. It went back and forth depending on how fast you rotated the magnet.

At the time this alternating current wasn't of much use since most electrical devices had been developed using batteries with their direct current. However, Hippolyte was able to install a ring - called a commutator - that switched the direction of the current when it was going backwards and so produced a direct current. This current, though, was in the form of pulses, not a constant flow, and so batteries were still used when electric devices - like the telegraph - were made commercial.

That there was some relation between magnetism and electricity was now clear. But it wasn't until 1865 that the Scottish physicist, James Clerk Maxwell (the middle name is pronounced "Clark"), decided to throw in some advanced mathematics. James's differential equations, commonsensically called Maxwell's Equations, established the quantitative relationship between electricity and magnetism.

One thing that was new about the equations was that they predicted that an oscillating electrical current would produce electromagnetic waves. These waves would be transmitted through space and were just like light waves. But they had different wavelengths.

The wavelengths in turn would depend on how fast the current in the wire switches back and forth. That is the wavelength was determined by the frequency of the current.

The relationship between frequency and wavelength was well known from the mathematics of waves. If these waves traveled at the speed of light (designated as c) and the alternating current had a frequency of ν, then the length of the wave (λ) is calculated by:

λ = ^c/_ν

So if the current flips back and forth 60 times a second - which we call 60 cycles per second - then we know the wavelength is:

λ	=	c/ν
	=	186,000 miles per second /60 cycles per second
	=	3,100 miles

That's a pretty long wave - visible light waves are only between 0.0000000002 and 0.0000000005 miles long. But in sending wireless messages, the longer wavelength would be a major advantage. Smaller waves hit an object and bounce back. Larger waves diffract - that is they bend around the object and keep going.

OK. It's all well and good to write equations saying these waves existed. But could you prove they existed?

Well, in 1887, a German professor named Heinrich Hertz decided to give it a try. If there were waves being sent though space caused by a current, then he figured the waves should induce current in another circuit.

What Heinrich did was set up a battery hooked into a electrical circuit but with a small gap created by two metal spheres breaking the circuit. The circuit had enough doo-dads to transform a low voltage direct current into a sufficiently high voltage alternating current where the circuit would be completed by producing a spark. If James was correct, then the current in this spark gap transmitter would produce electromagnetic waves which would then travel to the other loop. The waves would then induce a current in the new loop, and you'd get a spark on that loop's gap as well.

To see an extremely schematic diagram of the apparatus, click the image to the right or just click here.

And by golly it worked. When Heinrich sent the current through the first loop and got a spark, he saw another spark in the other loop. True, the spark was so faint that he had to use a microscope to see it. But it was definitely there.

Getting the Message

It didn't take long for people to start thinking that Heinrich had found the essential ingredients for sending telegraphic messages without wires. If you put a switch in the circuit that would only close when pressed down, the duration of the spark could be short or long. That is, you could make a dot or a dash and send a message in Morse Code.

Within a year or so the chief engineer of Britain's General Post Office, William Preece (that's his real name, not a misprint), was given the job of sending messages across water to a lighthouse. Yes, you could use an underwater cable - after all, there was already one across the Atlantic - but William's job was to dispense with the wires.

William managed to build a lab model that more or less worked. But it wasn't that great. Things got even worse when he tried to send a message any distance. He calculated that to send a signal across a short channel he needed an antenna several miles long.

An even bigger problem than sending the message was receiving it. It just wasn't practical to decode a message by looking at microscopic sparks. However the Indian scientists Jagadish Chandra Bose found if you inserted a tube of metal filings called a coherer into the circuit, the current from the radio waves aligned the filings and induced a change in the voltage. With a set of headphones - yes, there were headphones back then - you would hear a beep. Long beeps were dashes and shorter ones were dots. A skilled telegrapher could easily write down the coded message.

Still, it was a rather clumsy arrangement. After the coherer received a signal, you had to get the metal filings back into a random alignment. So you needed an automatic tapper that gave the tube a rap after each signal was received. But since there wasn't anything better, it would have to do.

So by the early 1880's we have at least three candidates who - quote - "invented the radio" - unquote.

1. James Clerk Maxwell, who discovered that radio waves should exist.
   
   
2. Heinrich Hertz, who proved the radio waves existed and actually created a radio wave transmitter and receiver.
   
   
3. William Preece, who actually invented a radio set specifically to send and receive a coded message.

The only problem was not one of these gentlemen had demonstrated you could reliably and dependably send intelligible wireless messages. So in that sense no one had (yet) "invented the radio".

Guglielmo Steps In

In 1894 or 1895 (he used both dates), young Guglielmo Marconi - a school dropout living in Bologna with his indulgent parents - read that Heinrich had died. The obituaries described Heinrich's contributions to science, particularly his proof of Maxwell's theories. So Guglielmo decided to see if he could invent - and pardon us if we shout:

A PRACTICAL AND USEFUL APPARATUS FOR SENDING WIRELESS MESSAGES!

We repeat. Guglielmo was trying to invent a practical and useful apparatus for sending wireless messages.

Guglielmo's story is a bit obfuscated since Guglielmo himself tended to alter the tale from time to time. But the basics of his family history are known.

Guglielmo's parents were not only indulgent but quite well-to-do. Actually "rich" is a better word. His mom, Annie, was from the famous Jameson family of Irish distillers (Jameson's whiskey was a favorite of the famous Irish rebel, Michael Collins). Annie had gone to Bologna to study music, and there she met Guiseppe Marconi.

Guiseppe was part of the Italian nobility and made his living by being part of the Italian nobility. That is, he lived off the family fortune. But for some reason Annie's parents didn't approve of the match. Still, Annie and Guiseppe got married and seemingly lived happily enough ever after.

Since he came from a rich landed family, some people disparage Guglielmo as a privileged rich kid. True, when he was born on April 25, 1874, it was in what honestly can be described as a baroque palace. And being rich certainly wasn't a handicap to Guglielmo's scientific ambitions.

With half of the family's genetic code originating in Ireland - then part of the United Kingdom - the Marconis went back and forth and spent a lot of time in Britain. Guglielmo even filed an application for UK citizenship. But before the application was granted, England's immigration laws were changed rendering the application invalid. Guglielmo may or may not have been chagrined, but at least his time in England helped him forge connections amongst the English uppercrust.

Back in Italy, Guglielmo showed an interest (and one might say had a genius) for the sciences but nevertheless he had difficulty in school. Even after Annie arranged private tutoring, Guglielmo showed no interest in completing any formal course work. He just wanted to study science, and in particular, electricity.

A nice thing about scientific equipment before the 20th century is that it was simple and cheap. Science was not yet Big Science (or rather, Expensive Science). There was also no clear distinction between the knowledgeable amateur and the skilled professional. Virtually any tinkerer could set up and repeat what famous scientists were doing and perhaps even make important discoveries.

Guglielmo knew - as did everyone - that a lot of people were interested in making a practical and useful wireless telegraph. William's experiments were well-known but it was also well-known that William had not yet developed a practical and reliable device.

So Guglielmo decided to see what he could do. He set up a spark gap transmitter in his attic and began to tinker.

First he found that the coherer - the glass tube filled with iron filings that detected the radio waves - didn't work too well. But when he used nickel with a little bit of silver, it worked much better. And yes, this "improvement" was indeed a bonafide new invention.

Eventually Guglielmo tinkered enough so he could send strong coherent messages across the room. His device was compact and simple. It could literally be fit into a suitcase. To go further he needed money.

At first, Guglielmo went to the Italian government. They listened politely to the kid and congratulated him for his discoveries. Then they told him to beat it.

Well, since Italy wasn't interested, Guglielmo decided to try his mom's country. So he wrote to William Preece at the GPO. Although the letter was from a twenty year old kid who had never graduated high school, William invited him to come to England and show them what he had. The demonstration was impressive enough that William got the GPO to fund further experiments.

What was it about Guglielmo that got William's attention? Well, it was mainly that Guglielmo was really focused on communication. He was not distracted by any desire to do fundamental research, which is what the university "Maxwellian" types were doing. The professors wanted to do science. Guglielmo wanted to send messages.

Backed by Britain's GPO, its engineers, and the money found therein, Gugliemo began making real progress. He improved the coherer, made a better tapper, produced a more efficient inductor, and he managed to connect a Morse relay to the transmitter which automatically recorded the message on a strip of paper. True, these individual components were from earlier inventors, but Guglielmo put them together and improved them so they would actually send telegraphic messages sans câbles.

But the biggest problem was designing an antenna big enough to send the messages further than the other side of the laboratory. First Guglielmo tried Mahlon's trick: run antennas up on kites. By altering the height of the wire, it could be "tuned" so the current would "resonate" and produce clear signals.

Later Guglielmo dispensed with kites and found he could simply drive a large rod into the ground. This "monopole" or "Marconi" antenna only needed to be half the size of the wavelength as it worked by reflecting the wave from the ground. Today's red and white radio masts are essentially what Guglielmo invented. The whole mast is the antenna, and they range in height from a yard or so to over two thousand feet.

In 1896 Guglielmo filed his first patent. It was very specific in stating that the invention was an apparatus for sending wireless messages. Then in 1897 the work had progressed enough to where he sent a message across Salisbury Plain. That got enough attention that he could now form a company, the Wireless Telegraph and Signal Company which changed in 1900 to the Marconi's Wireless Telegraph Company. The stock quickly rose from $3 a share to over over $22.

With the increasing number of stockholders and the attendant cash provided, Guglielmo quickly developed a commercial product that could send messages a goodly distance. The radio sets themselves were still remarkably compact, and the British navy recognized that such radios on ships could be invaluable. So they became one of Guglielmo's first and best customers. The Italian navy also bought some radios.

Then in 1900, Guglielmo achieved what he had been striving for all along. He sent a message - the letter "S" - across the Atlantic.

Or did he? Some doubt it. It may have been that this was simply static which - as random patterns often do - appeared to have a systematic pattern. Still, most historians do accept the date of 1900 as that of the first trans-Atlantic wireless communication.

Knowing that the operators also had to know how to fix the sets if they broke down, the company even provided the operators for the ships. So even if true cross-Atlantic transmission was as yet unreliable, ships could send wireless messages in relay.

One thing was certain. Guglielmo - or rather the Marconi Radio Company - was producing and selling reliable radio transmitters and receivers that were capable of sending coherent and lengthy messages across the land and to ships at sea. Guglielmo was in business.

Radio was soon proving its value. In 1909, the USS Republic collided with another ship. The radio operator was able to send out distress messages and 1700 people were rescued. Perhaps not coincidentally this was also the year Guglielmo won the 1909 Nobel Prize in Physics. Even today, ship-to-ship-to-shore transmissions are important means of communications.

So what about those who claim Guglielmo didn't invent the radio? Well, perhaps we should avoid hindsight and cite a contemporary opinion, that of the English electrical scientist and engineer John Ambrose Fleming. In 1904 he wrote:

Marconi's invention was not any particular element but the combination of the elements, some new and some old, which made Hertzian wave telegraphy possible ... prior to 1896 there was no wireless telegraphy and subsequent to 1897 there was no wireless telegraphy except that initiated by Marconi.

Although we see James was indulging in a bit of simplification, he was substantially correct. Although Guglielmo's equipment was soon improved on by others, the first person to send real radio messages extended distances was Guglielmo. That he combined previous inventions and discoveries to produce new and practical innovations doesn't detract from this fact.

Ironically what kept the other and - quote - "more qualified experts" - unquote - from making a working radio was that they kept futzing around. They were scientists and visionaries and wanted to do science. This scientific futzing and visionizing often sent them off on the wrong tack.

Probably the best example of someone being misled by the lack of direction - or rather heading off into the wrong direction - was the Serbian scientist and engineer Nikola Tesla. Nikola had gained massive fame (and a lot of dough) when George Westinghouse bought the rights to his patents on electric generators. George had provided the electrical lighting or the World's Fair at Chicago in 1893. By using the generators at Niagara Falls, George demonstrated the advantage of alternating current over direct current.

Originally in Europe and later in America, Nikola had worked for Thomas Edison. As the story is usually told, Tom had promised Nikola a big bonus but later said he had only been joking. Miffed, Nikola left.

But in his own telling of the tale, Nikola said the stingy jokester was not Tom, but Charlie Batchelor, Tom's "Manager of the Works". But the real reason Nikola left was probably that he thought that Tom was wasting time by not working on alternating current.

So Nikola started up his own consulting company, and in May 1888, he filed a number of patents for what are called polyphase generators. These machines produce electrical power not in a single wire but in multiple coils where the peak currents are offset. Polyphase alternating current generators - called "polyphase alternators" - produce more power with better consistency than single phase generators.

Nikola's patents were themselves not immediately suitable for making truly commercial viable generators. The final work was completed by the in-house Westinghouse engineers such as Charles Scott and Benjamin Lamme. But one particularly important task for Nikola was helping George land the financing for the Niagara Power Plant. Nikola's undeniable skill in explaining technical issues to the non-specialists was crucial in convincing the Big Boys to hand over the Big Money.

The success of the new generators got Nikola thinking. Alternators produced useful electricity that could be sent hundreds of miles, but you still had to string the wires. So why not invent generators that would distribute the electricity, but without the wires?

We have to emphasize: Nikola was not interested in wireless radio but in wireless power. And this goal - as worthy as it was - sent him down a losing path from which he never recovered.

The problem with sending electrical power without the wires is that the electromagnetic waves disperse through space and so the power gets diluted down. That is, the intensity of the wave decreases with the distance. If you have a 50,000 watt signal coming from the antenna on Long Island by the time the signal gets to Paris you'll have almost nothing there.

Now if you're talking about radio, having a signal fade due to the inverse square law isn't that big of a deal. A faint message can still be coherent. And you can also add additional power at the receiver to amplify the signal. But if you are sending wireless power, then adding more power at the receiving end so you could have more power makes no sense.

Nevertheless by 1898, Nikola had J. P. Morgan - yes, the J. P. Morgan - to fund construction for a wireless power transmitter on Long Island. Called Wardenclyffe Tower, the transmitter was supposed to send electrical power across the Atlantic.

In 1902 and after Guglielmo was making the news by sending real wireless messages, Nikola told J. P. that his Tower would send Morse code, too. Later Nikola would claim he could send voice messages as well. Or at least in 1915, an article appeared that stated:

Mr. Nikola Tesla has announced that as the result of experiments conducted at Shoreham, Long Island, he has perfected a new system of wireless telegraphy and telephony in which the principles of transmission are the direct opposite of Hertzian [radio] wave transmission.

In the latter, he says, the transmission is effected by rays akin to light, which pass through the air and cannot be transmitted through the ground, while in the former the Hertz waves are practically suppressed and the entire energy of the current is transmitted through the ground exactly as though a big wire.

Mr. Tesla adds that in his experiments in Colorado it was shown that a very powerful current developed by the transmitter traversed the entire globe and returned to its origin in an interval of 84 one-thousandths of a second, this journey of 24,000 miles being effected almost without any loss of energy.

There's a wee problem with what Nikola's told the reporter. First, 1915 was more than a decade after Nikola started telling J. P. that he would soon have wireless power and communication. And despite his claim he had finally "perfected" the Tower, construction on it had long since halted unfinished.

The source of the story that J. P. Morgan had pulled his money because he didn't want to finance free power for the masses remains rather elusive. One recent biography told the story and the only reference was another recent biography. J. P. most likely had balked because Nikola's original estimate of $100,000 but had quickly ballooned nearly half a million. And far from pulling the plug, J. P. told Nikola he was welcome to bring in new investors into their agreement.

Secondly, by 1915 voice transmission by radio was already old hat, and Nikola had nothing to do with its invention. It was in 1906, that the Canadian engineer and scientist, Reginald Fessenden, had broadcast voices and music from Nova Scotia to ships at sea. In 1910 - less than five years later - there had even been a broadcast from the stage of the Metropolitan Opera House.

Thirdly - and this is the big problem - there's Nikola's claim that he had created a new type of wave that traveled 24,000 miles in an interval of 84/1000 of a second. That means the waves traveled at 275,714 miles per second.

Now anyone claiming that there are "Teslartzian" waves that travel at more than 150 % the speed of light will leave modern scientists scratching their heads - or rather laughing behind their hands. To this day, there is no indication that anything travels faster than the speed of light. That's nothing - no particles, no waves.

A year later, Nikola amplified (no pun intended) his belief that (ptui) "Hertzian waves" were hogwash. In 1916, an article reported:

Further, it may be said that Tesla, all in all, does not believe in the modern Hertzian wave theory of wireless transmission at all.

It's almost like Nikola didn't know what he was talking about.

Or as one historian of radio stated:

Tesla was, without question, very skillful at generating large, noisy sparks with the aid of step-up transformers tuned to resonance (the famous Tesla coil) and he seems to have really believed that, since Marconi used sparks in his wireless work, then he too must be a wireless pioneer.

There is, however, not a shred of credible evidence that Tesla did anything more than just talk about radio (in 1901, for example, he claimed that two years before he had received radio signals from Mars), and nothing in the historical record supports his grandiose claims. It is clear, in fact, from what he did write, that Tesla actually had only the slightest (if that) understanding of electromagnetic radio physics; he claimed, for example, that "his" electric waves were both immune to the inverse-square law and that they traveled faster than light.

Tesla does appear to have sincerely believed his own outrageous statements; he lived in a delusional world of self-aggrandizement that became increasingly cut off from reality. His only human joy seems to have been feeding the pigeons of New York City, where he died in a hotel room a lonely, bitter man."

This judgement may appear a bit harsh. But it is true that Nikola was spending all his time and his backers' money on building gigantic Tesla coils that, truth to tell, did nothing but make massive sparks. Well, they did a bit more. In Colorado Springs, Nikola once fired up his gigantic coil and blew out all the power in the city.

So it's all the more ironic that even before 1898 that Nikola invented something that was new, novel and useful - and wireless. That was devising and even demonstrating that he could control a model boat by remote control. The big irony is that although he quickly got a patent for the invention, because he was spending so much time trying to develop wireless power, he let the invention languish until the patent ran out.

As for the the Wardenclyffe Tower, it never sent any wireless power or messages. It was finally torn down in 1917. But Nikola kept going.

Or at least he kept giving interviews. When he was pushing 60, he told a reporter:

"When world wireless telephony, the transport of bodies and materials, and the transmission of energy for all industrial and commercial purposes become facts, the earth will have shrunken in size so as to put nations in close touch and make international complications and wars an impossibility!"

Yes, the wireless transport of bodies and materials.

So maybe Nikola really did invent the Star Trek Transporter. But as far as who invented a radio that, as the commercials say, really, really worked, we have to give the nod to Guglielmo.

References

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