I was in tears last night watching a programme on Sky One called Braniac Science Abuse 3. I have been an avid follower of this show that creates all the experiments you wanted your chemistry teacher to do, but they said it was too dangerous. Their speciality is blowing up caravans. Anyway the experiment went as follows. Premise: When you swallow Helium from a balloon your voice gets higher because the vocal chords restrict. Would the same happen if you swallowed Helium and then played into a wind instrument? Experiment: Take one school orchestra with a variety of wind instruments 3 flutes, 2 clarinets, 1 trumpet, 2 saxophones and various strings, plus a brave teacher playing the piano. Get a test sound that shows the pitch is relevant to a school orchestra, and decide that they are generally playing within the same range of Hertz. Give Helium to one of each the following instruments. Flute, Clarinet, Trumpet and Saxophone. Listen and determine that certain players are in a different key whilst still playing the same notes. Single out trumpet player, and get her to play a note, reliably informing us that it was a B, read 440Hz concert A. Take a draft of Helium and play the same note, it amazingly starts on the right note and shifts up a whole tone, and then a fraction of a note up again. Conclusion: Helium not only tightens the vocal chords but is also expelled at a faster rate as it is lighter than air, causing the vibrations to change the pitch of the note. Daft bit: If you want to play a C trumpet part on a Bb instrument have copious amounts of Helium at the ready, assuming your " A Lazy Trumpeter"