Electric Universe

by David Bodanis

  •—————•

  From Guglielmo Marconi’s lecture accepting the Nobel Prize,

  11 December 1909:

  At my home near Bologna, in Italy, I commenced early in 1895 to carry out tests and experiments with the object of determining whether it would be possible by means of Hertzian waves to transmit to a distance without the aid of connecting wires. My first tests were carried out with an ordinary Hertz oscillator [which used sparks to generate waves in a manner similar to Hertz’s early experiments]. With such apparatus I was able to telegraph up to a distance of about half a mile.

  In August 1895 I discovered a new arrangement….

  From Submarine Telegraphs: Their History, Construction, and Working, by Charles Bright, 1898:

  Marconi has succeeded in making the resonator work…at a distance of nearly nine miles. It is…the very latest thing in Inductive Telegraphy.

  Marconi’s wireless telegraph is based on the principle of turning Hertzian waves to account in transmitting them…by means of electric sparks….

  From “Signalling Through Space Without Wires,” a public lecture by Sir W. H. Preece, the Royal Institution, London,

  4 June 1897:

  In July last year Mr. Marconi brought to England a new plan. Mr. Marconi utilizes electric or Hertzian waves…he has invented a new relay….Excellent signals have been transmitted across the Bristol Channel.

  Proceedings of the Royal Society, 28 May 1903:

  The remarkable success of Marconi in signalling across the Atlantic suggests a bending of the waves round the protuberant Earth.

  •—————•

  The signals that Marconi sent were simply more powerful versions of the invisible waves--the undulations in the electric and magnetic fields--that Hertz had produced in his laboratory. Since they “radiated” outward, they stopped being called Hertzian waves and came to be called “radio” waves.

  •—————•

  From the Encyclopaedia Britannica, Eleventh Edition, 1910:

  High power stations are now used for communicating across the Atlantic, and messages can be sent by day as well as by night….Hertzian wave telegraphy, or “radio-telegraphy,” as it is sometimes called, has a position of the greatest importance in connexion with naval strategy and communication between ships.

  Message received from SS Olympic, 1,400 miles off

  U.S. East Coast, 14 April 1912:

  ... ... / -- .. -- .-- --. .. --.--. / .--. .-- --. /

  .. --. -- -------- / .. --.--. . --... . .--. ----. /

  ... .. --. --.-- .. --. ----. / ..--. .-- ... --

  (The message reads “SS Titanic ran into iceberg. Sinking fast.” It was received by a young telegraph operator, David Sarnoff, at Wanamaker’s department store in Philadelphia.)

  •—————•

  Many inventors and other interested parties began to imagine fresh ways of using this new device.

  •—————•

  Memorandum from David Sarnoff, former telegraph operator, to Vice-President Edward J. Nally of the Marconi Wireless Telegraphy Company of America, 1915:

  I have in mind a plan of development which would make radio a “household utility” in the same sense as the piano…the idea is to bring music into the home by wireless….The receiver can be designed in the form of a simple “Radio Music Box” and arranged for several different wave lengths, which should be changeable with the throwing of a single switch or pressing of a single button.

  If only one million families thought well of the idea, it would…yield considerable revenue.

  •—————•

  Sarnoff’s memo was rejected. A decade later, in the 1920s, sales of radio apparatuses by the company he founded--RCA--had made it one of the most powerful industrial firms in the world.

  Radio transformed every country where it was introduced. Although telegraphs and telephones sent messages at extremely high speed, they still could only link one individual with another. Radio waves, however, weren’t locked within a narrow copper wire. Since the physical nature of those waves is to spread in all directions, radio sent its information so widely that the term broadcasting became the popular way to describe this new effect.

  Suddenly, national brands became far more popular to shoppers than they had before; local sports teams increasingly attracted a nationwide fan base; the cult of celebrity--as with Hollywood stars--became even more widespread. Listeners felt that radio broadcasts were being aimed personally at them.

  And politics changed as well.

  •—————•

  Adolf Hitler, Mein Kampf:

  All propaganda has to appeal to the people and its intellectual level has to be set in accordance with the receptive capacities of the most-limited persons among those to whom it intends to address itself. The larger the mass of men to be reached, the lower its purely intellectual level will have to be set….Even from the most impudent lie something will always stick.

  •—————•

  In America, the demagogues who used radio to spread their message always remained in a minority. But in Japan and several European countries it was different: the Nazi Party’s innovative use of radio transmissions was a major factor in its electoral success in the years leading to 1933.

  As the 1930s went on, German tank commanders began practicing with radio command of large armored and aerial formations they could use to destroy neighboring countries. A few researchers in other countries began to wonder if the power embodied within radio waves could be enough to keep enemy war machines at bay. The British government especially wanted to know. The Royal Navy had long protected the country by sea. Would it be possible to use radio waves to protect it by air?

  •—————•

  From A. P. Rowe, Secretary of the Committee for the Scientific Survey of Air Defence; to H. T. Tizard, FRS, Rector of the Imperial College, 4 February 1935:

  Dear Mr. Tizard,

  A copy of a secret memorandum prepared by Mr. Watson Watt on the possible uses of electro magnetic radiation for air defense, is enclosed herewith….

  7

  Power in the Air

  SUFFOLK COAST, 1939, AND BRUNEVAL, FRANCE, 1942

  Many technicians had stumbled on radar over the years, but the first ones had found it impossible to get their superiors to believe them. In September 1922, for example, Albert Taylor and Leo Young of the U.S. Navy were trying to send a simple radio signal across the Potomac River, but kept getting some sort of interference. They looked up; a steamship was in the way. Yet when they tried to get funding to investigate this effect, they were scoffed at: how could a bulky steamship have any effect on ghostly, weightless radio waves? Similar effects were reported in Russia, France, and most other places where radio was used a lot, but the response was almost always the same.

  It didn’t help that radio technicians tended to be quiet sorts. But, luckily for the survival of Britain, and indeed of the civilized world, at least one radio expert was overwhelmingly the opposite in personality. His name was Robert Watson Watt, and in 1935 he could be found working in the dreary reaches of the atmospheric research station of the National Physical Laboratory, near the equally dreary English town of Slough. The poet John Betjeman loved the south of England, but after getting to know Slough, even he was inspired, famously, to write:

  Come, friendly bombs, and fall on Slough

  …and blow to smithereens

  Those air-conditioned, bright canteens…

  A direct descendant of the James Watt who’d perfected the steam engine, Watson Watt had been a promising university student in Scotland, but things had never quite worked out since then. His marriage had long since tapered off to boredom (“I was…a dull, drab partner in the small residuum of the twenty-four hours that were not monopolized by work and sleep”), and pretty much everything else was on the same level (“I am five foot six, tubby if you want to be unkind, chubby if you want to be a little kind; a bit of a meteorologist…t
hirty years a Civil Servant.”)

  That last item was the problem. Given his great family legacy, Watson Watt had never imagined he’d end up middle-aged, middle-income, and not even of middling fame, there on the edges of governmental research departments, miles from London.

  And then, in January 1935, a request fell his way, from heaven, or rather—it seemed as good—from the Air Ministry in London. A contact there asked him if there was any truth in the rumor that evil “death-rays” could be sprayed from radio transmitters at an aircraft. The question itself was easily enough answered in the negative, for radio waves are too weak to damage a hulking aircraft. But Watson Watt wasn’t about to let the matter drop so easily.

  He knew that the moment he sent his reply back, the door that was now briefly open to the London Ministry would close; he’d be stuck in Slough, perhaps forever. But if he played with the idea and came up with something better, then—who knew?—he might be regularly called to London. There would be all-expenses-paid day trips on the railway; briefings he could modestly deliver; superior people to meet; possibly a promotion.

  What actually resulted from his response to the casual inquiry—ultra-top-secret missions to Washington, private briefings for Churchill; a knighthood from the Queen, and vast funds from a victorious nation—was beyond any of his imaginings. But for the moment, in this wet January of 1935, he actually had to come up with something interesting to tell the Air Ministry in London, and this presented a problem. Although Watson Watt was very proud, he was also rather honest with himself. He understood that although he was a good enough meteorologist, he was, in his sad estimation, at best “a second-rate physicist” and “a sixth-rate mathematician.”

  He’d made friends, however, with a colleague in his office, Arnold Wilkins, who hadn’t been at Slough long enough to resign himself to second-rateness. Wilkins was keen to calculate what else might happen when a radio wave was sent out in the direction of an incoming aircraft. The invisible waves that Faraday and Maxwell and Hertz believed in—those magic-carpet-like undulations in the force field—wouldn’t carry enough power to melt the plane or injure the pilot. But could they do something else?

  Wilkins thought about it and realized they provided a way to use an enemy’s airplane against itself. From his original training in physics, Wilkins knew something important about metal and, in particular, about what could happen inside the metal of an airplane’s body. Watson Watt had some training in this area, but wasn’t as deft with calculations, which is why Wilkins led the way.

  Back in the time of Faraday and William Thomson, only a few theorists had imagined that invisible waves could affect ordinary solid substances and make them move. This was fair enough, for when there are no separate charged particles available—when all the charges are tucked away in balanced groups inside an atom as in the ordinary objects around us—then the electric and magnetic forces have nothing to latch on to. (Gravity, by contrast, doesn’t have opposing parts that can be balanced into neutrality, and so is always noticeable.)

  By the time Wilkins and Watson Watt were collaborating, though, it was becoming clear how the electric effects might work. In the 1930s an atom was popularly thought of as a miniature solar system, at the center of which is a big, heavy nucleus, like our sun. On the outside, spinning in distant orbits, the separate electrons are like our planets. Radio waves are just undulations in a stretching electric and magnetic field, so when a radio wave or the like swirls over one particular atom, it tries to tug loose some of those electrons.

  Often a wave has no effect. Since the electrons in our bodies are generally held pretty tightly to the nuclei at the center of our atoms, our bodies are invisible to most of those fields. A radio wave will hurtle right through us; to radio waves, we are ghosts. Even the atoms inside ordinary rock or bricks are constructed in such a way that radio waves fly through, which is why we can use a cell phone inside a house.

  Metal is different. The atoms in iron or aluminum are more loosely constructed, and are like solar systems that don’t particularly care about their outermost planets. Although the majority of these atoms’ electrons stay in orbit, the outermost ones are free. A strip of shiny aluminum with several billion atoms can be viewed as a galaxy of several billion stars which all have some planets orbiting close, but have let the outer ones escape. It’s as if innumerable electrically charged Neptunes or Plutos were floating loose among the stars in that galaxy, joined by similar refugees from other solar systems.

  That’s what it’s like in the metal wing of an airplane. When a radio wave storms into one of these miniature galaxies in an aircraft’s metal, the innermost electrons of each miniature solar system might be buffeted a little, but they won’t be knocked very far. But the more distant electrons, the errant, solitary, orphaned electrons, the ones flying loose in the miniature galaxy, are a different story. The radio wave that flies through the metal “nabs” them, and carries enough power to start tugging them along.

  When this happens inside a tiny metal receiver like the one within a cell phone, the solitary electrons start wobbling, that wobble is magnified, and our crucial information—such as “Hey, I’m in the car!”—is transmitted. But Wilkins realized that when a radio wave hits a much larger expanse of metal, the effect is more dramatic.

  In an enemy airplane there are yards and yards of such vulnerable, waiting metal. Any radio wave we send in its direction accelerates the loose, mobile electrons there. And each electron is always surrounded by its own personal force field. If the electron is left still, that force field will be fairly still and no signal will be produced from the airplane’s wing. But when the electron is made to ripple from side to side, that force field ripples as well. (This was what Maxwell and Hertz had realized.)

  By aiming a radio transmitter at the targeted plane, trillions upon trillions of electrons could be made to ripple in unison and serve as tiny bubbling radio transmitters of their own. In other words, by pumping up invisible radio waves, Wilkins could force the enemy plane to become a flying transmission station! The entire airplane turned into an antenna that could not be switched off.

  The big question, though, was whether the transmission would be powerful enough to be detected. For the sky is big, but radio waves are small. Most of the radio waves beamed outward would disperse and miss the airplane, or be very weak by the time they reached it. Wilkins did the calculations. Even though the launched wave might disperse so widely that only one thousandth of its strength would be available to tug on the metal electrons in a plane four miles away, that would still be enough. Once again, it was the very minuteness of electrons that allowed this to work. Wilkins showed that even that diffuse a wave would make about 60 quadrillion (60,000,000,000,000,000) electrons start rushing back and forth each second at any given point in the airplane’s wing. The invisible radio waves generated by those rushing wing electrons would be powerful enough to detect back on the ground. (Stealth aircraft, invented decades later, avoid detection partly because the paints used don’t allow much incoming radar energy into the plane’s metal skin, partly because the aircraft’s surfaces are angled so that anything it does reflect will aim away from the original transmitter.)

  Watson Watt had supervised Wilkins’s work, sort of, so it was fair enough that when the memo went back to the Air Ministry in London, Wilkins was generously mentioned as an important collaborator. But it was Watson Watt’s name, alone, that went on top.

  Wilkins didn’t mind, he was happy to take a backseat role, for he knew something about Watson Watt that the mandarins in Whitehall were about to experience. For Watson Watt loved to talk—no, not just talk, he loved to expostulate, to verbally cogitate, to burble and engulf and generally overpower anyone he was near with a torrent of words. At a court case about patent rights, where his substantially ad-libbed remarks totaled a third of a million words, Watson Watt remarked that “it would be disingenuous to leave any impression that I did not enjoy this experience.”

  Now, eag
er to push this idea that might free him from Slough, he went into overdrive. He sent reminders to London, and then a second memo (“I have thought it desirable to send [this] immediately rather than to wait…”). Watson Watt met the mild, pipe-smoking civil servant A. P. Rowe, who’d initiated the query; then lofted higher, for lunch with Rowe’s superior, Henry Wimperis, at the Athenaeum Club. Pretty soon, senior individuals—very senior individuals—were interested in what Watson Watt was proposing.

  It helped that Britain had few alternative methods for defending against German air attacks. In World War I, blind people with excellent hearing had been placed under the likely path of incoming Gotha bombers and asked to don stethoscopes attached to large Victrola-like horns. More recently, in the early 1930s, a giant concrete “ear,” two hundred feet long and twenty-five feet high, had been built on marshes near the Thames, aiming over the Channel, where possible enemy aircraft might emerge. Neither of those techniques worked very well. The only chance of succeeding was to create wobbles in the invisible electric force fields that stretched out from the charged electrons in transmitters. Those waves would continue wobbling outward, possessing enough power to kidnap and redirect the electrons in the metal of incoming planes.

  It sounded like science fiction, but within three weeks, Watson Watt had convinced Wimperis, Rowe, and everyone else within earshot that the time was ripe for a full-scale test. He wouldn’t need any special equipment. The “enemy” plane could just be an ordinary RAF bomber; the transmitting radio station could simply be one of the powerful BBC Empire masts at Daventry in Northamptonshire, which was already broadcasting regularly; the oscilloscope to detect the waves that would surely be flung back out by the bomber’s electrons could be borrowed from a research colleague.

  At this point Watson Watt knew he had not just to convince the scientific staff at the ministry—who would be tolerant of teething problems—but also the operational leaders, and in particular, the extremely suspicious Air Chief Marshal, Hugh Dowding, known even to his friends as “Stuffy.” A great number of weapons that promised seemingly magical power for the defense of Britain had come Dowding’s doubting way, and all of them had failed operational tests. His resources were so slight that he couldn’t gamble on backing the wrong one.