HI,
Yes many people before Edison were playing around with the incandescent light but they had the problem of the wire burning out way too quick.
Go take a very small wire, and place when you place 24 volts (or something) on it. the wire will heat up and glow orange, then after a half an hour or so the wire will have burn in to.
Edison used tungsten filament, which burn white. To stop the wire from burning out so quick, he used argon inside the bulb.
I am sure lots of other people had put too much current on a small wire and saw it glow then burn out. But the person(whoever it was) who was able to stop the melting, therefore allowing light for much longer peroids, should be the inventor of the incandescent light.
It's still a very inefficient way :roll: