The AM Forum

These are the world's first two vacuum tubes, the 1905 Fleming Valve and the 1907 Deforest Audion. 

I photographed this display at the Antique Wireless Association's annual conference museum tour in August 2004.

The AWA museum is located in East Bloomfield, New York.

Nice!

          We owe quite a bit to those two gentlemen, especially Leon DeForest.
    Let's hear it for Themionic Emmission and Cathode Rays! Edison had noted
    a curious effect that a smalll current would flow to a positive charged tin foil
    wrapped around his light bulb but not a negative one.  He saw no  use for it.

DeForest turned out to be somewhat of a charletan.  He stumbled onto the control grid quite by accident and never really understood how the triode tube worked, but had the foresight to realise the idea was valuable and acquired the patent.  That discovery is what made him famous, but the ideas for several of his later inventions turned out to be stolen from other inventors, including the regenerative detector he stole from Edwin Armstrong.

Armstrong, the inventor of  frequency modulation, committed suicide in 1954 in the midst of a legal battle over another of his patents: with RCA over the rights to use FM for television sound.

http://www.leedeforest.org/defendant.html

As I recall, the first tubes, as we know them, were rectifiers, whose one way current effect was discovered when a collector (anode) was added to a light bulb in an attempt to collect the material that would boil off the filament and coat the inside of the glass envelope, making the bulb get dim.