Rubens Tube: a Physics Project

Hey instructables! Its been a while since I've been able to post anything; college apps have been sucking away all my time. I'm taking a break from them now to show you guys how several friends of mine and I build a Rubens tube.

Last year, several friends of mine and I set off to create the COOLEST end of year physics project ever. We considered catapults and trebuchets, but we found that to be a bit too simple. Someone the year before us had already done a potato cannon. We wanted to do something different. Having seen some instructables on Rubens tubes in the past, I thought it would be cool to create one and study how it works from a physics standpoint.

Now, what is a Rubens tube? A Rubens tube, also known as a flame tube, is a metal tube with small holes drilled down its length. One end is capped off with a solid cap and the other end is covered in a sound permeable membrane. This tube can demonstrate standing waves in sound with fire when the resonance frequency is played through one end.

Basically, you can make fire dance when you play music through the tube.

I've included the power point file we used when we presented the tube to the class in case you guys are interested in learning a bit about the science behind how the Rubens tube works.

Feel free to leave any questions in the comments below.

Materials:
Metal  tube (preferably aluminum)
Drill
1/16 inch drill bits
PVC fittings
Brass fittings
Small propane tank (or other fuel source)
Gas regulator
Vinyl tubing
Balloon or a thin latex glove 
Rubber bands
Silicon tape/ glue
Masking tape
Pencils
Speaker with amplifier
Sound source (frequency generator)
* Marshmallows *

*Disclaimer: If you decide to do this yourself, please exercise some common sense. Fire is dangerous and so is a can filled with flammable gas.*