Early amplifier

Hi,
I was doing some research and came across an early type of amplifier, the whole thing was a bit vauge, but it said that it took the sound and using a candle, a needle, a cone ande something sealed in a glass envelope amplified it, does anyone have an explanation to this?
Thanks SlicRic

This is part of some of the first microphones ever invented, that used a gas flame to detect the presence of audio and pass it to a "speaker."
Google: early microphones; gas microphones, etc.