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On October 5, 2025, this website is going to begin counting down the Top 100 Milestones from the First 100 Years of Television over 100 weeks until September 7, 2027.
First, we’re lining up all the puzzle pieces needed to get to that date.
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Starting in the 1880s, all the research toward the ultimate dream of “moving pictures that could fly through the air” revolved – quite  literally – around the principles first articulated by Siemens and first demonstrated by Bidwell: that light could be converted into electricity and back again.

Spinning Wheels

Paul Gottlieb Nipkow was a 23-year-old student in Berlin, studying mathematics and physics in 1884 when he was awarded German patent number DE30105C for his “Elektrisches Teleskop” – the  “Electric Telescope.^⁠1”

Nipkow was hardly an established scientist or an inventor in the mold of Edison, Bell or Siemens.  He was an aspiring undergraduate, immersed in the heady atmosphere of the age when innovations like the telegraph, the telephone, and electric light transformed daily life.  

Legend has it that on Christmas Eve of 1883, Nipkow sat in his rented lodgings and puzzled over how he might send an image down a wire.^⁠2 The problem was simple to state but baffling to resolve. How could a complex visual scene be reduced to a current of electricity? His solution was to scan the subject sequentially, breaking it down into linear elements one line at a time.

To achieve that sequential scan, Nipkow devised a flat disk perforated with a spiral of small, evenly-spaced holes.  As the disk spun, each hole swept across a different strip of the image. Those scanned lines of reflected light would land on a light-sensitive photocell on the opposite side of the disk from the subject, creating a fluctuating electrical current.  

At the receiving end, a second disk, synchronized with the first, reversed the process, tracing modulated lines of light across a screen to replicate the original pattern.  

Crude though it was, Nipkow’s concept was the first to express the essential principle needed to make television possible: sequential scanning, line by line and frame by frame. 

Nipkow himself never built an “Electric Telescope” but his idea dominated research in the field and compelled those that followed in his footsteps to bark up the wrong tree for the next four decades.

The Nipkow disk. Did it “work?” Or just demonstrate what would not work?

Vacuums & Tubes: 1642 – 1879

To fathom the next generation of innovations that ultimately led to television, we must first return to antiquity and take on one of the vestiges of ancient wisdom. 

In his Physics (Book IV, 4–9), Aristotle declared that “nature abhors a vacuum.” For nearly two millennia after that, the doctrine of “horror vacui” relegated the concept of “empty space” to philosophy rather than science. That did not change in any meaningful way until the 17^th century. 

In the early 1600s, engineers in Renaissance Italy were perplexed when their suction pumps refused to draw water any higher than about 32 feet, no matter how strong the mechanism. If, as Aristotle had insisted, “nature abhors a vacuum,” then why did the pumps stop there?  They brought the quandary to the celebrated scientist and philosopher Galileo Galilei, who suggested that the limit might not be set by nature’s resistance to  emptiness, but by the weight of the surrounding air – an idea that went beyond Aristotle and hinted at a new physics of the atmosphere.

To test Galileo’s proposition, one of his contemporaries, Gasparo Berti, erected a 35-foot lead tube, sealed at one end, filled it completely with water, and then inverted it into a basin. The water fell away from the sealed top until it stabilized at roughly the same 32-foot limit the pump-makers had encountered.  That left a mysterious empty space above.  Could that empty space have been an actual vacuum, or was it filled with some previously unknown matter?  Berti’s experiment showed that air pressure seemed to set the limit, but it left unsettled the ancient debate over whether a genuine void could exist at all.

A year after Galileo’s death in 1642, his student and successor Evangelista Torricelli devised a more elegant test.  Instead of water, he used mercury, which is about 14 times denser than water, and required a tube only 3 feet high. When the mercury-filled glass tube was inverted into a dish, the mercury column fell until its weight was balanced by atmospheric pressure on the mercury in the dish. That still left an empty space of about 2 or 3 inches at the top which became known as the “Torricellian vacuum.”  This was the first reliable demonstration that – Aristotle notwithstanding – a sustained vacuum could in fact exist in a laboratory setting (if not in nature).

Torricelli also observed that the size of the empty space above the column of mercury varied between 2 and 3 inches, depending on the surrounding atmospheric pressure. With this discovery, Torricelli had effectively invented the barometer – arguably the first “vacuum tube” of any type, and the precursor of all the vacuum science that evolved through the centuries that followed.

Torricelli’s mercury column showed conclusively that a vacuum could exist.  In the 1650s, the German engineer Otto von Guericke took that discovery one step further by inventing  the vacuum pump – the first mechanical pump capable of pumping most of the air out of a vessel. 

In 1654, Guericke conducted a dramatic demonstration of his invention for the Holy Roman Emperor Ferdinand III, using what became known as the Magdeburg Hemispheres. Guericke obtained two copper domes from his hometown, sealed them together, and then pumped all the air out of them with his vacuum pump. The resulting vacuum holding the hemispheres together proved so powerful that teams of horses could not pull them apart.  Only when air was readmitted did the spheres fall apart effortlessly, making a spectacle of the invisible power of the vacuum. 

Over the next two centuries, experimenters steadily refined the art of making and sustaining vacuums. Improvements in glassblowing and pump design allowed scientists to create ever higher vacuums and explore an array of electrical effects within.

In the 1850s, German glassblower Heinrich Geissler created delicate, airtight tubes filled with trace amounts of gas. When he ran an electrical current through the tubes, they produced striking patterns that varied in color according to the type of gas in the tubes. Scientists used these “Geissler tubes” to study electrical discharges in low-pressure gases. For the general public, the hugely popular novelties and their parlor tricks fueled the Victorian fascination with invisible forces: electricity, magnetism, and other “ethereal” phenomena.

A generation later, English physicist William Crookes pushed these devices into even higher vacuums. Crookes embedded two electrodes into his tubes: a negatively charged ‘cathode’ and a positively charged ‘anode.’^⁠3  When a high voltage was applied to the terminals, a visible electrical discharge seemed to stream away from the cathode across the vacuum toward the opposite end of the tube.^⁠4 This phenomenon became known as “cathode rays.” 

The real potential of the Crookes tube was demonstrated in 1879, when he mounted a small Maltese cross inside the tube; when the current flowed, the cross cast a sharp shadow on the glowing glass at the far end, suggesting not only that the cathode rays traveled in a straight line, but that they might be used to render images.

This is a good demonstration of a Crookes tube; starting at ~55 seconds, you can see the effect of a magnet on the cathode rays

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¹ Nipkow’s patent was actually granted on January 15 1885, but was retroactively dated back to January 6, 1884.  Apparently the patent could not be granted until Nipkow’s future wife paid the fee for him.

² 1884 is before anybody seriously considered sending electrical signals through the air.  The idea of radio waves began in 1886-1888, when Heinrich Hertz in Karlsruhe, Germany, built spark-gap transmitters and receivers that produced and detected radio waves across his lab bench.  Hertz was only trying to prove principles mathematically predicted earlier by James Clerk Maxwell.

In 1894 Guglielmo Marconi began experimenting in Italy with Hertz’s methods, with the express goal of sending useful signals. By 1895, he could transmit Morse code about a mile. This is usually considered the birth of practical radio.

³ The terms “cathode” and “anode” were coined in 1834 by Michael Faraday during his experiments on electrolysis. Drawing on Greek roots, he used anode (from anodos – “way up”) for the terminal where current enters a device, and cathode (from kathodos –  “way down”) for the terminal where current leaves. By Crookes’s time, these names had become standard in describing the positive and negative electrodes of discharge tubes, even though the true nature of electric charge and electron flow would not be fully understood until later.

⁴ Crookes tubes required several thousand volts to operate, typically in the range of 2–10 kilovolts (kV). At a few kilovolts, the tubes would produce glows and shadow effects; at the higher end – 10–15 kV – the beams became even stronger, producing fluorescence on the glass and the sharp “cathode ray” effects that fascinated Crookes and later experimenters.