Rijke's tube turns heat into sound, by creating a self-amplifying standing wave. It is an entertaining phenomenon in acoustics and is an excellent example of resonance.
The gauze is optimally placed one quarter of the length from the bottom of the tube. The ones I've made are also of 50 mm diameter glass, with about 3 mm spaced brass wire gauze. I've made quite a few of these and have kept a set which is tuned to a major triad plus the octave. They are deafening!