This is one of my favourite things to do
not just because I love drinking wine
but because i love making music.
A few years ago I was at a conference
and i saw this couple called 'The Glass Duo'
who played the glass harp, an instrument made out of wine glasses
And i thought: 'I've got to try it'.
It is really simple to do, you just need any glass with a stem.
And some glasses work better than others
so it's worthwhile trying lots of different glasses.
Now you need to wet your hand and you just need to apply some pressure
around the rim of the glass
and hold the base really steady.
You can start softly and then apply more pressure
until you get a good note.
I love doing this with my daughter, not just because it's an amazing phenomenon
but because it allowed us to do some really simple science together,
where we can investigate and observe how changing one thing can affect another.
So Tilly, we're going to look at making some sounds today
with different objects.
How do you reckon you could make a sound with that?
Do you want to try pinging one of the glasses and seeing what sound it makes?
So, what happens when you hit the glasses?
It makes a noise.
What happens when you hit the different glasses?
It makes a different noise.
How is that noise different to that noise?
Because this one is lower.
OK so, I'm going to show you a different way to make a sound with the glasses.
For this we have got to get our hands wet.
Do you want to?
I'm going to dip my finger in this juice
and I'm going to put it around the glass like that.
Can you hear that? Would you like to try?
That's it, I'll hold the glass.
Keep going.
Well done you are making a note, that's really good!
Let's do it with a different glass.
So what's happening with that one?
It's making a different noise.
It's a different noise isn't it, well done.
That's a nice one. I think this one is the best.
One of the reasons that I find this so delightful
is that it's surprising.
If you didn't already know about it, you wouldn't guess
that you could do this with a wine glass.
When you hit a wine glass like this,
it makes it vibrate and that produces a sound.
It's not always easy to see but if something is making a sound
some part of it must be vibrating.
In the case of making a wine glass sing like this,
it's not obvious what's making the glass vibrate
and what's actually happening, is as you move your fingers around the rim of the glass
they repeatedly stick and slide off the glass.
It's this repeated sticking and sliding around the glass that makes the glass vibrate
and produces the note.
Different glasses vibrate in different ways
and so produce different notes.
Putting fluid in the glass also makes it vibrate in a different way.
And the more fluid there is in a glass
the lower the pitch of the note.
It's different.
With enough glasses and a little bit of practice you might be able to do something like this:
Plays "Ode to joy'