Scientists in his era, figured light in deep space needed a conducting medium and suggested luminiferous aether as a candidate.
What if they rigged up a bell jar, inside of which, was a light on one side, and a target on the other. Then, when they evacuated all the air from the jar, and shone the light on the target, wouldn’t they have realized that light doesn’t need the aether?
Or am I missing something?
It was probably technically impossible to create a perfect vacuum so supporters of the ether theory would be able to argue that the light waves traveled through the remaining gas. And while I’m not overly familar with the theory of ether, I believe some scientists thought it was something other than ordinary matter.
The aether wasn’t made up of matter, so removing the matter had no effect.
They DID do that experiment. They knew all about vacuums. That’s essentially why they had to come up with the aether idea - to explain how light could propagate through airless space. You seem to be under the mistaken impression that they thought aether was made up of air. They didn’t.
I didn’t have the impression that they thought ether was made up of air.
What bugs me is they felt they had to make up something like ether to account for the transmission of light in space.
If scientists knew about vacuums, and knew about airless space, and if their (nearly) airless bell jar experiments strongly indicated light didn’t need a propagating medium, why couldn’t they make the leap that “ether” isn’t needed and probably doesn’t exist?
Because our experience is that waves are disturbances in something, therefore some medium that supports those waves has to exist. Seeing light go across vacuum shows that it’s clearly not air. It therefore had to be something else, something intangible. the idea of such an intabngible medium, otherwise undetectable, bothered other people as much as the idea of waves in nothing bothered the supporters of “ether”.
Aether was also needed as a reference frame - this was before relativity, before we found out the speed of light is the same for everyone. It was logical to think that the speed of light was defined relative to some medium, and if you were moving relative to this medium, the speed of light would appear to be different.
The Michelson-Morley inteferometer is the experiment used to show there is no aether …or ether either.
I know what that “intangible medium” is: Dark Matter. See how ether solves so many problems that physicists had to reinvent it? 
And the Michelson-Morley inteferometer does not prove there is no aether, ether, or æther, for that matter. It simply showed that ether did not behave as they had hypothesized.
I think you need to have a little bit more historical perspective. After all, today we talk about photons and other subatomic entities in terms of “particles” and “waves,” even though we know quite well they are not really either. And as dropzone indicates, physicists today invent terms such a “dark matter” and “dark energy” in order to discuss phenomena whose nature we simply don’t yet understand. I suspect that a century from now all these terms will sound as quaint and archaic as the “luminiferous aether” does now.
But in their favor they do not require one to use “Character Map” or remember ASCII codes to spell them.
Simon Singh’s new book “The Big Bang” has a really good layman’s discussion of this.
I guess you’re referring to my E = mc². I apologize for that. It never occurred to me that there’d be a problem. (With NumLock on, it’s Alt-0178 for the ².) But you can just call me E for short — or even U for Unthinking. I’ll answer to either. 
Or we could just call you “Mr. Squared.”
Actually, I thought he was talking about the “æther.”
But not nearly as cool. I propose renaming “dark matter” and “dark energy” to atramentous corporeity and crepuscular palpitation, respectively. And “exotic matter”? Let’s try meta-extrinsic gravitationally-antipodal sparcely-occuring corpus.
I’ve got a term for M-Theory, too, but it can’t be used in polite company. 
Stranger
What, you don’t like WIMPs or MACHOs?
This sounds more like heavy petting in the park at sunset.
MEGA-SOC? :dubious: