The portrate to the left is one of Sir W. Ramsey in his laboratory in 1887 when he took head of department at University College London.
In the photograph below to the right is Georges Claude with apparatus. Georges Claude is stood to the left in the picture.
How it all Started
The word neon comes from the Greek "neos," meaning "new."
Neon gas was discovered by Sir William Ramsey and Maurice. W. Travers in 1898 in
The events leading up to its discovery discribed below courtesy of UCL 2010.
In 1895, Henry Meirs, at the British Museum, told Ramsay that, on heating, a mineral cléveite gave off a gas that Meirs though might be nitrogen. Ramsay thought that it might be a compound of argon. He sent out his technician to a minerals dealer for a specimen of cléveite and, in two days, he showed that it was a new inert gas, helium, the spectrum of which Sir William Crookes had observed from the light of the sun in 1868. With an atomic weight of 4, it fits between hydrogen and lithium, in the same group as argon.
They were now faced with an almost insuperable problem: they have found the first and the third member of the Group, and now need to find the intermediate member, and Ramsay says: "Here is a supposed gas, endowed no doubt with inert properties, and the whole world to find it in". After 2 years, he decided that it might be hiding in the atmosphere. At the Royal Institution in Piccadilly, Dewar had liquefied air in 1872. Ramsay and his student, Maurice Travers , cooled bulbs of argon in liquid air, and separated off the uncondensed portion. Under an electrical discharge it gave blaze of crimson light, and they called it Neon, the newcomer. (source: University college london 24/04/2010)
Believe it or not “neon” (this term is used to describe the effect as opposed to the gas) was first conceived in 1675, when the French astronomer Jean Picard observed a faint glow in a mercury barometer tube. When the tube was shaken a glow called barometric light occurred, but the cause of the light (static electricity) was not then understood.
As time went by our knowledge of electricity became more profound and by 1855 the Geissler tube named after Heinrich Geissler, a German glassblower gained control of an electric arc; Gas in the tube was placed under low pressure and an electrical voltage was applied, the result was Light! This light came from the bombardment of free electrons. As one electron left an atom and then joined another atom a photon of light is emitted and depending on the atom of gas being used depends on the "colour" of light from the photon. Neon being red/crimson. Sir William Crookes worked with Geissler tubes further developing them and experimented with objects in the tube and magnetic fields leading to x-ray tubes and the pre TV, radio and rectifier valve experiments. As soon as we were able to generat electricity and not use batteries, many people experimented with applying electric power to tubes of gas. Several electric discharge lamps or vapor lamps were invented from 1900 onwards in
“Electric discharge lamp is a lighting device consisting of a transparent container within which a gas is energized by an applied voltage, and thereby made to glow.“
The French engineer, chemist, and inventor Georges Claude, was the first to apply an electrical discharge to a sealed tube of neon gas to create a lamp that was stable, this was through the "emitter" coating he applied which lengthed the electrode life. This was around 1902. Over the next few years Claude worked with various emitters and gas pressures and Voltage/Ampage combinations till Georges Claude was able to display the first neon lamp to the public on
In 1912 Jaques Fonseque, Claude’s associate, sold the first commercial sign to a
In 1922 the first neon signs were installed in
In 1923, Georges Claude and his French company Claude Neon, introduced neon gas signs to the
Before Claude harnessed the beauty of neon gas signs in
As time proceeded developments and discoveries occurred from time to time. Starting with colours. In order of discovery were blue (Mercury), white (Co2), gold (Helium), red (Neon), and then different colors from phosphor-coated tubes. The mercury spectrum is rich in ultraviolet light (UVA, UVB and UVC) which in turn excites a phosphor coating on the inside of the tube to glow. Phosphors are available in most colours. Together with coloured glass the full spectrum is Available. This is another story though and all started in 1926. though Moores lamps were used a long time before this filled with Carbon dioxide.
The most recent developments in “Neon” lighting is the use of Electronics to control the arc in the lamp and the power used. Switch mode power supplies with built in electrical protection were developed in the 1980s and now all Neon Signs and Neon Lighting is protected by sophisticated electronics for safety and economy.
The most recent development (circa 2004) is an environmental development. Today all neon tubes are 100% recycled, the glass is separated from the electrodes and mercury gas vapor. The glass is then re-used; the mercury is distilled and reused. The electrodes are made from Iron and are melted down for reuse, they could return as a part on your next dishwasher!
So neon is today a very modern light source and is the most environmentally friendly light source of all for signage and any other use you care to mention. BUT esentially remains the same today as it did 100 years ago!
Here Georges Claude is stood with apparatus. It is apparent that the box fastened to the wall is a Mcleod guage used for measuring high vacuums. I used a very similar guage in the 1980s to measure vacuums in tubes made at Oldham Signs in Leeds.
The bottle being handled by Claude will have likely contained gas (probably 100% neon). Alternatively, It is possible this was early experiments, The glass bottle may have been evacuated and used to calobrate the Mcleod guage but not likely or to evacuate gas tubes but again not likely. If it is true and the bottle contains 100% neon gas then the bottle could not have contained "preasurised" neon gas as the ground joint would have separated, therefore the gas in the bottle would be less than one atmosphere as are todays glass gas flasks like I buy to fill my neon tubes. the twin taps you can see on the outlet are used as "gates" to allow tiny amounts of gas to travel into the manifold and can be measured with the mcleod guage. Note the large bath of Charge mercury at the bottom of the "box" cabinet, this is driven into the Vacuum measure by the 1000mBar (or so) of atmosphere acting on it. Modern McLeod guages are much smaller.
Image courtesy of Boyer—Roger Viollet/Getty Britannica online
Georges Claudes patent was for the stabalisation of the electrodes within the tube. Collie claimed he had already made a sucessful neon gas filled tube that lit sucessfully years earlier. Claude actually fine tuned the electrode shells by developing a coating for the electrode which ment the tube "cleaned up" any unwanted particles into the electrode and so lengthened the tube life dramatically. So it can be said that Claude developed the first sustainable and "sucessful" neon tube.
Copy right: Julia Bickerstaff 2010
U.S. Patent 1,125,476. Filed by Georges Claude, Jan. 19th, 1915.
Geissler and Crookes tubes
Image copyright from The Cathode Ray Tube Site http://members.chello.nl/h.dijkstra19/
Kristian Birkeland was "the first space scientist" he looked deeply at the way that electrons travel through magnetic flux's and was able to replicate saturns plasma outer rings using a terrella (magnetised steel sphere) in a vacuum.