Egyptian Lighting

I’m pretty sure I’ve figured out how to make a light bulb without anything more “high tech” than copper wire, bronze fittings, glass / ceramic jars, and maybe a wheel with some metal on it; plus, the Baghdad Battery.

The fist step is to gang together a set of those Baghdad Batteries into a battery of about 10 to 20 Volts. That current is then sent to a switch. This could either be a single switch like in the old points and condenser ignition, or it could be a wheel where there are alternating patches of bronze, and wood, that make contact between two wires, or don’t. This makes a pulsing DC current that is “close enough” to AC for a transformer to work. (Cars work this way, so not a hypothetical)… points or electronic ignition ‘chop’ the Direct Current that goes to the “coil” as 12 V DC (chopped) and comes out about 50,000 Volts of spark…

That kind of “coil” is relatively easy to make. Yes, really good ones need a special kind of iron core, but any old chunk of iron is ‘good enough’ to make an ok coil. We don’t really need to jump things up to 50,000 VDC here, just a few hundred to thousand would be fine. In fact, even air core would be OK… see below on Tesla Coils.

Now, the next step, is to make that wobbling quasi-AC at high voltage into a truely spectacular voltage. One that can ionize air (or CO2 or…) in a bottle over a foot or two distance. To do that, there’s a couple of ways. But first, just so you know what we’re trying to make here, the Egyptian Lightbulb:

https://en.wikipedia.org/wiki/Dendera_light

The “mainstream” view is some fanciful concoction of lotus blossoms and deities, snakes and Osirus… The “Fringe View” is more mundane:

Fringe view

In contrast to the mainstream interpretation, there is a fringe hypothesis according to which the reliefs depict Ancient Egyptian electrical technology, based on comparison to similar modern devices (such as Geissler tubes, Crookes tubes, and arc lamps). J. N. Lockyer’s passing reference to a colleague’s humorous suggestion that electric lamps would explain the absence of lampblack deposits in the tombs has sometimes been forwarded as an argument supporting this particular interpretation (another argument being made is the use of a system of reflective mirrors). Proponents of this interpretation have also used a text referring to “high poles covered with copper plates” to argue this but Dr. Bolko Stern has written in detail explaining why the copper covered tops of poles (which were lower than the associated pylons) do not relate to electricity or lightning, pointing out that no evidence of anything used to manipulate electricity had been found in Egypt and that this was a magical and not a technical installation.

A technically oriented person might note that copper and bronze are highly valuable and that if there were a secret way to use electricity to make light, killing off the dozen folks who knew it would result in the Idiot Victors having a lump of copper and bronze to melt down to make swords to slay more folks with clue… leaving no evidence to speak of…

If, right now, our society collapsed back to pre-electrical, just how many folks 1000 years from now would know what a computer was, how to program FORTRAN, what made a Raspberry Pi special, or why we spend so much time “worshiping” some Goddess named Lady Gaga?

Metals and paper decay fast. Ceramics not so much. IFF it is not in or on a ceramic, don’t expect any evidence of it in 1000 years. Especially anywhere wet / damp / humid.

So here’s the light bulb:

Egyptian Light Bulb

Egyptian Light Bulb

The problem is that this looks like an “arc discharge” bulb, and that takes very high voltage. It also works best with modest frequency AC, not low volts DC from a crummy battery.

So the question is: HOW to turn the small battery volts into BIG discharge arc volts without a whole lot of technology? I’d like to limit it to copper and bronze wires and fittings, coils and flat plates, and ceramics and glass, if possible. The Egyptians had all of that. Oh, and a wheel as on their chariots to do the “chopping” of DC to AC even if square wave.

So what can make a few hundred or thousands of Volts (chopped DC) into something up in the hundreds of thousands to millions? (Mega Volts, or MeV).

https://en.wikipedia.org/wiki/Tesla_coil

Yes, at this point I’m assuming the Egyptians could figure out how to use a wheel with bumps to cause a periodic switch press, or how to put bands of bronze on a wheel such that sometimes they conducted between two wires / pads and sometimes it was bare wood. I’m also assuming they could send this pulsed DC from their Baghdad Batteries down wires to “something” that could use pulsed DC to make higher volts. A lot higher…

I’m not seeing any of this as “beyond the pale” for the Egyptians. They had wheels. The Baghdad Battery is a known artifact. They had copper and bronze and knew how to make wires and cables. Winding a coil is common (much jewelry has that as a motif) and using a bit of iron as a core for the primary circuit is a “nice to do” that they could do, but not essential.

So I’m willing to postulate they can make pulsed D.C. of a few hundred to thousand Volts through just that kind of system that we invented at the very start of our age of electricity. Then what?

Rotary spark gap –

These use a spark gap consisting of electrodes around the periphery of a wheel rotated by a motor, which create sparks when they pass by a stationary electrode. Tesla used this type on his big coils, and they are used today on large entertainment coils. The rapid separation speed of the electrodes quenches the spark quickly, allowing “first notch” quenching, making possible higher voltages. The wheel is usually driven by a synchronous motor, so the sparks are synchronized with the AC line frequency, the spark occurring at the same point on the AC waveform on each cycle, so the primary pulses are repeatable.

Nothing, nothing at all, prevents making just such a wheel as the thing that chops the battery current into the first stage of a car-type “flyback” transformer to make hundreds or thousands of volts in a nice fat pulse. Then you send it into a very simple coil set-up and it becomes more than enough to ionize air and make it glow.

Tesla Coil Circuit Diagram

Tesla Coil Circuit Diagram

So a wheel and flyback wound transformer take the place of that input AC voltage and transformer. The result is the same. At the next point, we have a capacitor (those two horizontal lines with C1 next to them). One of those can be made via a jar (glass or ceramic) with metal inside and outside. Then is the spark gap. Two metal rods in free air. And finally the Tesla Coil itself. That is just a big coil of wire (or two coils) and an optional “top hat” of metal that we can replace with a light bulb discharge tube if desired.

But what I find of particular interest, is the ‘bipolar’ Tesla coil. It looks rather a lot like the ‘base’ of the Egyptian Lightbulb, except that the ‘spark gap’ isn’t two wires in free air, but a couple of metal ends inside a glass envelope.

Bipolar Tesla Coil

Bipolar Tesla Coil

Compare, in particular, the “support” under the big end of the “light bulb” and the overall look of the Bipolar Tesla Coil… Now adding a ground lead to the far “lotus blossom” end and you have the whole magilla…

Next to that “support” end of the bulb, we have a figure with 2 faces one each way. Denoting A.C. current perhaps? The “wire” comes from the box he is on, so I’d suspect that was a caricature of “the guy who chops battery DC into AC with that wheel thing”…

But I said a couple of ways… Tesla also used a “Magnifier coil” on his basic system to make even higher voltage. But what caught my eye was a related system. Used at the very start of the age of electricity as a “medical device” (of dubious quality… then again, send a few MeV though me and I’m definitely going to feel “energized” ;-)

https://en.wikipedia.org/wiki/Oudin_coil

Oudin Coil Schematic

Oudin Coil Schematic

Oudin Coil picture

Oudin Coil picture

How it works

Oudin and Tesla coils are spark-excited air-core double-tuned transformer circuits that use resonance to generate very high voltages at low currents. They produce alternating current in the radio frequency (RF) range. The medical coils of the early 20th century produced potentials of 50,000 to nearly a million volts, at frequencies in the range 200 kHz to 5 MHz.[4] The primary circuit of the coil has Leyden jar capacitors (C) (one in the Tesla and two in the Oudin coil) which in combination with the primary winding of the coil (L1) make a tuned circuit. The primary circuit also has a spark gap (SG) to excite oscillations in the primary. The primary circuit is powered by a high voltage transformer or induction coil (T) at a potential of 2 – 15 kV. The transformer repeatedly charges the capacitors, which then discharge through the spark gap and the primary winding. This cycle is repeated many times per second. During each spark, the charge moves rapidly back and forth between the capacitor plates through the primary coil, creating a damped RF oscillating current in the primary tuned circuit which induced the high voltage in the secondary.

In earlier Oudin circuits the two coils were separate, not magnetically coupled, with a small horizontal primary “D’Arsonval” coil of 20-40 turns with a tap connected to a large vertical secondary “Oudin resonator” with many turns of fine wire (400 – 600 in large coils, 100 – 300 in small ones), connected to the high voltage terminal on top. In this circuit the high voltage was generated entirely by resonance in the high Q secondary coil. The addition of the “resonator” coil to the “D’Arsonval” coil was Oudin’s contribution; the rest of the circuit was invented by Jacques D’Arsonval.

In later Oudin circuits the coils were magnetically coupled, forming an autotransformer, so the primary induces an EMF in the secondary by electromagnetic induction. Both coils were usually wound on the same coil form, the primary consisting of relatively few turns of heavy wire at the bottom with an adjustable tap, connected to the secondary winding, made of many turns of fine wire. Oudin found this circuit produced higher voltages due to the large turns ratio of the transformer.

Note that a Leyden Jar really is just a glass or ceramic jar with metal foil or plates on the inside and outside. Trivial for an Egyptian to make.

So a large coils of wire with a ‘tap’ on it for tuning, two jars with foil or metal inside and out to make capacitors, and an input from a wheel / transformer (another coil) and Baghdad Battery. With all that, you get arcs that can make light in free air. All that is left is to make it more ‘tame’ with a “lightbulb” wrapper.

One of THE most efficient and common light bulbs most folks don’t know about is the “metal halide discharge” lamp of the more generic “High Intensity Discharge” lamps. Basically a glass bubble with oxygen free air in it and some metal salts. You can have all sorts of metals used. Things like Mercury, or even Sodium.

https://en.wikipedia.org/wiki/Metal-halide_lamp

A metal-halide lamp is an electric lamp that produces light by an electric arc through a gaseous mixture of vaporized mercury and metal halides (compounds of metals with bromine or iodine). It is a type of high-intensity discharge (HID) gas discharge lamp. Developed in the 1960s, they are similar to mercury vapor lamps, but contain additional metal halide compounds in the quartz arc tube, which improve the efficiency and color rendition of the light. The most common metal halide compound used is sodium iodide. Once the arc tube reaches its running temperature, the sodium dissociates from the iodine, adding orange and reds to the lamp’s spectrum from the sodium D line as the metal ionizes. As a result, metal-halide lamps have high luminous efficiency of around 75 – 100 lumens per watt, which is about twice that of mercury vapor lights and 3 to 5 times that of incandescent lights and produce an intense white light. Lamp life is 6,000 to 15,000 hours. As one of the most efficient sources of high CRI white light, metal halides as of 2005 were the fastest growing segment of the lighting industry. They are used for wide area overhead lighting of commercial, industrial, and public spaces, such as parking lots, sports arenas, factories, and retail stores, as well as residential security lighting and automotive headlamps (xenon headlights).

Now I’m not going to assert that they invented the Metal Halide Discharge lamp as we know it. I’m just pointing out that the use of a very high voltage current limited discharge can act a lot like a ballast (limits the current / Wattage) and that a glass bowl full of relatively inert gas (like CO2 from a fire) with some salt on the elctrodes would make a dandy light. (FWIW, I’ve put salt on wires from my 18 kV neon sign transformer and it makes a dandy Egg Yolk Yellow light… Other salts give other colors).

So take your Oudin coil or Tesla coil output (from your interrupted current from your Baghdad batteries) and apply it to metal ‘arms’ coated with your typical desert salts. Put the thing inside a glass bowl, and burn a bit of something inside to clear out the oxygen. Viola, electric light with 1700s era tech and none of it beyond the Ancient Egyptians to make.

https://en.wikipedia.org/wiki/Gas-discharge_lamp

Gas-discharge lamps are a family of artificial light sources that generate light by sending an electrical discharge through an ionized gas, a plasma. Typically, such lamps use a noble gas; (argon, neon, krypton, and xenon) or a mixture of these gases. Some include additional substances, like mercury, sodium, and metal halides, which are vaporized during startup to become part of the gas mixture. In operation the gas is ionized, and free electrons, accelerated by the electric field in the tube, collide with gas atoms.
[…]
History

The history of gas-discharge lamps began in 1675 when French astronomer Jean-Felix Picard observed that the empty space in his mercury barometer glowed as the mercury jiggled while he was carrying the barometer. Investigators, including Francis Hauksbee, tried to determine the cause of the phenomenon. Hauksbee first demonstrated a gas-discharge lamp in 1705. He showed that an evacuated or partially evacuated glass globe, in which he placed a small amount of mercury, while charged by static electricity could produce a light bright enough to read by.
[…]
The father of the low-pressure gas discharge tube was German glassblower Heinrich Geissler, who beginning in 1857 constructed colorful artistic cold cathode tubes with different gases in them which glowed with many different colors, called Geissler tubes. It was found that inert gases like the noble gases neon, argon, krypton or xenon, as well as carbon dioxide worked well in tubes. This technology was commercialized by French engineer Georges Claude in 1910 and became neon lighting, used in neon signs.

So there you have it. Using not much more than a Baghdad Battery, copper wire and coils, a jar with metal foil inside and out, a wheel and ‘chopper’ switch, and a glass bowl with CO2 in it via a candle or such, and maybe a bit of salt on the electrodes, you, too, can invent very effective electric lighting with (your choice) 1600s A.D. or 2000’s B.C. technology.

Somehow I think they could have made it work. In the 1600s, we had not yet figured out how to make Roman Cement again, nor how to do many other things done by Romans, Greeks, and ancient Egyptians in prior eras… Who’s to say the light bulb was not one of them? I find it harder to believe that in 4000 years of playing around with metals, wires, salts, and such they NEVER made coils, made a Baghdad Battery as their neighbors did, never once made a switch in a wire, etc. etc. Besides Ramesses II was a Red Head and we know how those folks can be ;-)

Microscopic inspection of the roots of Ramesses II’s hair proved that the king’s hair was originally red, which suggests that he came from a family of redheads. This has more than just cosmetic significance: in ancient Egypt people with red hair were associated with the god Seth, the slayer of Osiris, and the name of Ramesses II’s father, Seti I, means “follower of Seth.”

So when your Dad was a follower of a God Slayer and you are “associated with the God Seth”, well, what’s a little thing like making electric lights…

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
This entry was posted in History, Tech Bits and tagged , , , . Bookmark the permalink.

20 Responses to Egyptian Lighting

  1. jim2 says:

    Use a voltage ladder

    https://en.wikipedia.org/wiki/Voltage_multiplier

    with diodes made of Cu2O

    https://hackaday.com/2016/05/01/home-made-diodes-from-copper-oxide/

    and caps made of ceramic and copper plates –

    VIOLA!

  2. E.M.Smith says:

    Interesting things those copper diodes… Seems not that hard to make.

    Of course, if one has a Baghdad Battery nothing prevents just making a few hundred of them in series and using DC to make an arc…

    Then there’s
    https://en.wikipedia.org/wiki/Geissler_tube

    A Geissler tube[1] is an early gas discharge tube used to demonstrate the principles of electrical glow discharge, similar to modern neon lighting. The tube was invented by the German physicist and glassblower Heinrich Geissler in 1857. It consists of a sealed, partially evacuated glass cylinder of various shapes with a metal electrode at each end, containing rarefied gasses such as neon, argon, or air; mercury vapor or other conductive fluids; <bor ionizable minerals or metals, such as sodium. When a high voltage is applied between the electrodes, an electrical current flows through the tube. The current dissociates electrons from the gas molecules, creating ions, and when the electrons recombine with the ions, the gas emits light by fluorescence. The color of light emitted is characteristic of the material within the tube, and many different colors and lighting effects can be achieved. The first gas-discharge lamps, Geissler tubes were novelty items, made in many artistic shapes and colors to demonstrate the new science of electricity. In the early 20th century, the technology was commercialized and evolved into neon lighting.
    […]
    Simple straight Geissler tubes were used in early-20th-century scientific research as high voltage indicators. When a Geissler tube was brought near a source of high voltage alternating current such as a Tesla coil or Ruhmkorff coil, it would light up even without contact with the circuit. They were used to tune the tank circuits of radio transmitters to resonance. Another example of their use was to find nodes of standing waves on transmission lines, such as Lecher lines used to measure the frequency of early radio transmitters.

    Another use c1900 was as the light source in Pulfrich refractometers.

    Geissler tubes are sometimes still used in physics education to demonstrate the principles of gas discharge tubes.

  3. E.M.Smith says:

    OMG, this thing looks just like the Egyptian “light bulb”:

    Even the tapered shape.

  4. jim2 says:

    I built a cold cathode tube using glass tubes. It was small. It created an electron beam which created a dot when it hit a phosphor coated microscope slide. Used a auto coil, FET, and 555 timer, I believe it was.

  5. jim2 says:

    I hadn’t heard of the zinc oxide diode before:

    http://sparkbangbuzz.com/zinc-oxide-diode/zinc-oxide-diode.htm

  6. E.M.Smith says:

    @Jim2:

    There’s a huge number of semiconductor materials. Lots of them suited to DIY play. A couple from
    https://en.wikipedia.org/wiki/List_of_semiconductor_materials

    Diamond, grey tin & tin (dioxide, sulphide), silicon carbide, sulphur, boron (nitride, phosphide, arsenide), aluminum (nitride, phosphide, arsenide), zink/zinc (oxide, selenide, sulphide, phosphide, arsenide), lead (sulphide, iodide),titanium dioxide, CuO & Cu2O, Iron oxide FeO, iron disulphide, nickle oxide NiO and just for fun, both silver sulphide and Uranium Oxide UO2 & UO3.

    If that can’t keep the home experimenter busy, you can move down to the alloy system listings… silicon-tin has a 1 V band gap.

    Personally, I like the pyrite one:

    Iron disulfide FeS2 0.95 Mineral pyrite. Used in later cat’s whisker detectors, investigated for solar cells.

    Easy to get, 0.95 V band gap, and makes crystal radios!

    It’s interesting that it took so long to discover semiconductors, really, given how many there are.

    Not sure how to dope pyrite, but somebody has probably already done it, or you could place it on another material for a junction…

    https://en.wikipedia.org/wiki/Pyrite

    A newer commercial use for pyrite is as the cathode material in Energizer brand non-rechargeable lithium batteries.

    Pyrite is a semiconductor material with a band gap of 0.95 eV.

    During the early years of the 20th century, pyrite was used as a mineral detector in radio receivers, and is still used by ‘crystal radio’ hobbyists. Until the vacuum tube matured, the crystal detector was the most sensitive and dependable detector available – with considerable variation between mineral types and even individual samples within a particular type of mineral. Pyrite detectors occupied a midway point between galena detectors and the more mechanically complicated perikon mineral pairs. Pyrite detectors can be as sensitive as a modern 1N34A germanium diode detector.

    Pyrite has been proposed as an abundant, inexpensive material in low-cost photovoltaic solar panels.] Synthetic iron sulfide was used with copper sulfide to create the photovoltaic material.

    So looks like sulfide a copper surface and then deposit some pyrite on it, or deposit some copper sulfide on a chunk of pyrite…

  7. E.M.Smith says:

    Interesting…

    https://en.wikipedia.org/wiki/Crystal_detector_(radio)#Types

    Historically, many other minerals and compounds besides galena were used for the crystal, the most important being iron pyrite (“fool’s gold”, iron disulfide, FeS2), silicon, molybdenite (MoS2), and silicon carbide (carborundum, SiC). Some were used with gold or graphite cat’s whiskers. Another type had a crystal-to-crystal junction instead of a cat’s whisker, with two crystals mounted facing each other. One crystal was moved forward on an adjustable mount until the crystal faces touched. The most common of these was a zincite-bornite (ZnO-Cu5FeS4) junction trade-named Perikon, but zincite-chalcopyrite, silicon-arsenic and silicon-antimony junctions were also used. The goal of researchers was to find junctions that were not as sensitive to vibration and unreliable as galena and pyrite. Some of these other junctions, particularly carborundum, were stable enough that they were equipped with a more permanent spring-loaded contact rather than a cat’s whisker. For this reason, carborundum detectors were preferred for use in large commercial wireless stations and military and shipboard stations that were subject to vibration from waves and gunnery exercises. Another quality desired was the ability to withstand high currents without damage, because in communication stations the fragile detector junction could be “burned out” by atmospheric electric charge from the antenna or high radio frequency current leaking into the receiver from the powerful spark-gap transmitter during transmissions. Carborundum detectors, which used large-area contacts, were also particularly robust in this regard.

    To increase sensitivity, some of these junctions such as silicon carbide were biased by connecting a battery and potentiometer across them to provide a small constant forward voltage across the junction.

    Foxhole radio from World War II

    The oxide layers that form on many ordinary metal surfaces have semiconducting properties, and detectors for crystal radios have been improvised from a variety of everyday objects such as rusty needles and corroded pennies. The foxhole radio was a crystal radio receiver improvised by soldiers during World War II without access to conventional sets. It used a razor blade and a safety pin or pencil lead to form a demodulating junction. Much patience was required to find an active detecting site on the blade. Unwanted rectifying junctions that form between metal parts of radio transmitter installations are still a source for interference, because they can produce harmonics of the transmitter frequency.

    So a used razor blade (oxide…) and a safety pin… or pencil.

    Or just a corroded penny…

    Somehow I think the Egyptians could have made copper with surface oxidation…

  8. jim2 says:

    I’ve got a pyrite crystal and have made a radio with it.

  9. jim2 says:

    No, I’ve got galena, not pyrite.

  10. Soronel Haetir says:

    What I find more interesting about semiconductors is how the transistor was first discovered in the 1920s but then lost until Bell put more work into it. And even more interesting is how my education claimed that Bell didn’t try to claim a patent when the truth was that the patent had already run, that Bell tried but it was rejected on the grounds of prior art. Worse to my mind is that it is now known that Bell was entirely aware of that work, that they started by trying the earlier claimed device.

    https://en.wikipedia.org/wiki/History_of_the_transistor

    I only learned about this when I bought a huge lot of Analog from the 1960s and they had an article that included Lilienfeld’s original patent application in one issue. He may have used a quad-pole rather than triode design but his diagrams are instantly recognizable to anyone with even passing familiarity to the field.

  11. E.M.Smith says:

    I had a galena one many decades ago. Undoubtedly tossed at some point by mandatory “cleaning up”… along with some great WWII earphones for crystal sets… also gone.

    I’d love to make one of those things again, but unfortunately, with my reduced hearing I’d almost certainly be unable to hear a crystal set so amplification needed.

    An interesting page here:
    http://www.bizarrelabs.com/foxhole.htm

    has a couple of designs shown. And an interesting note on another detector material:

    Prisoners of war during WWII had to improvise from whatever bits of junk they could scrounge in order to build a radio. One type of detector used a small piece of coke, which was a derivative of coal often used in heating stoves. The piece of coke used was small, about the size of a pea. A small board was used and a depression was cut into it near one end to hold the coke. A screw and, if available, a screw cup were used to hold the coke in place. A wire lead to the receiver was run from this to the coil/aerial (see Set 5).

    so just some chunk of carbon and a screw. Guess you don’t really need diamond to make a carbon detector ;-)

    Now if only there was anything worth listening too on AM these days… /snarc;

  12. p.g.sharrow says:

    Actually, to make your lamp work a Wimshurst Electrostatic Generator would be the most likely solution.
    https://en.wikipedia.org/wiki/Wimshurst_machine
    Light weight, portable, well within the abilities of ancients to construct, scales up, Just needs someone to crank it…pg

  13. E.M.Smith says:

    @P.G:

    Your link lead me to a solution only needing falling water… and metal buckets.

    https://en.wikipedia.org/wiki/Kelvin_water_dropper

  14. Larry Ledwick says:

    That fox hole radio is exactly the design my dad built for me to show me how a crystal radio was built, old razor blade a piece of pencil lead bound to a safety pin, and copper wire wrapped around an old oatmeal cereal cylinder.

  15. jim2 says:

    You can still get piezo earphones – the kind you stick in your ear.

    https://www.amazon.com/Crystal-Radio-Earphone-Impedance-3-5mm/dp/B0052EE0AU

  16. p.g.sharrow says:

    Ah! just remembered. Tesla created detectors with iron filings in a tube to act as an detector for his Pike’s Peak experiments originally to detect far off lightning strikes. The filings changed their conductivity during the EMP pulse of the far off lightning so it could be seen as a meter twitch of a galvanometer. This also became part of Marconi’s Radio Telegraph…pg .

  17. p.g.sharrow says:

    Back in 59 while in 6th grade I constructed several “Crystal” sets. the ear piece element of an old Ma Bell phone would work, The pizo electric earphone worked well, but the best one I used was a headset for the B-17 voice operated crew intercom that my uncle gave me. If I left the head set open on my school desk the entire class of 32 could listen to the ballgame on KFBK if they were quiet! The teacher loved it…pg

  18. jim2 says:

    pgs – I remember reading about the ‘coherer’.

  19. jim2 says:

    DEchoherer!

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