Clocks Go Back, Super Sized Blue Peter Bite

This is Blue Peter, but mini.

Expect epic adventures,

makes, bakes, badges, pets,

presenters and your host.

We've only got five minutes, so get ready for your Blue Peter adventure.

Time. It's constantly ticking, isn't it?

And we use it every day, we use it to organise our lives

and our schedules and it kind of keeps us all in sync.

Sometimes it even lets us know when we're a little bit late for school...

You know who you are.

Erm, so if I'm going to talk about time, I'm going to need a clock.

But this is Blue Peter, so I'm not going to use any old clock face.

I've brought you to see the most famous clock in the world.

Ha-ha. Oh, yes.

We've been invited to parliament to help with a very special task.

The changing of the clocks.

Taking me through each important stage in the process

are the clock mechanics, Ian, Hugh and Paul.

All the work happens at the top, which means climbing 334 steps.

This is one of those times when you've got to speed the film up.

'I'm actually climbing Elizabeth Tower.

'The name Big Ben refers to the bell at the top.'

BELL RINGS

But why do we change our clocks in the first place?

To explain that, we need to go into space.

The earth is tilted as it orbits the sun.

During the summer we have longer days

because we're facing towards the sun

and in the winter we have shorter days

because we are facing away from it.

A British builder called William Willett first suggested the idea

of changing the clocks in 1907 in order to make

the most of our daylight hours.

'Phew! I'm finally here.'

-Here it is, the great clock of Westminster.

-It is great, isn't it?

Look at that.

It may not look like the clocks you have at home,

but this 161-year-old mechanism turns the hands

on the world-famous clock face.

It weighs a whopping 4½ tonnes.

That's the same as a fully grown elephant.

Now, we know Big Ben is the sound that you hear,

but the bit that you recognise of course is the clock face

and we're actually behind it.

It's huge, it's massive, isn't it? Do you know how big?

Seven metres across. And you've got 312 panes of white glass in it.

This is our inspection hatch, we can actually look outside,

make sure that there's no panes of glass broken.

I think maybe we should probably inspect the outside

and have a quick look while we're here, you know.

Lovely view of London.

Oh, I can see our camera crew down there. Hello!

Now, you see that is just awesome.

Now, we can't get this camera out there

to show you what the view's like,

but I have one of these little cameras that will do just the job.

So, have a look out here.

That is me hanging out of this huge monument in London.

Isn't it beautiful?

Do you know what time it is?

Right, enough dangling out of this world-famous building,

I've got a job to do.

First, we have to turn the lights off.

This takes place just after 10pm

and it allows the team to change the time without anyone outside noticing.

-Here we go, west is going off.

-Yeah, west.

-South.

-Yeah.

That's done, you've switched off the lights.

-And we can now set the clock.

-Yes, we can.

-Amazing.

Now, with Ian's help we need to stop the mighty Big Ben from ringing.

BELL RINGS

This is the fantastic piece of equipment that we have to use.

-Yeah, I reckon I can work out where this goes.

-Yeah.

-Until it's nice and tight.

-Yeah.

-Now, that's not going anywhere.

-Nope, that's it.

That's barred off now, it's not going to make a noise.

With Big Ben silenced we can get on with changing the time.

Unlike a clock at home that you simply wind back one hour,

this mechanism can only go forwards,

so Paul has to move it on to exactly midnight,

where it will be held until real time catches up.

-Are you ready?

-Yeah, ready.

So, what's actually happening on the outside of the clock face now

is in complete darkness you'll just see the silhouette

of the hands moving round.

Time flies when you're having fun, eh?

Three, slow it down a bit. Two...

Bang on, there you have it. Midnight.

Midnight is chosen to allow for several hours of maintenance work

to take place. And one of the most important jobs, winding the clock.

There we go.

Years ago, my grandma used to have a watch and it used to have

a little wheel on the side you would wind up and that would give

the watch energy, it would give it power, so it would keep working.

This doesn't have batteries in it, which means we effectively

-have to wind this up, don't we?

-We do.

OK, before we start, how many of these have I got to do?

You've got to do 120 to make it last three days.

Quite a work out, isn't it?

Bit more sweat.

Harder.

That's it. Excellent.

'Phwoar. I never thought this would be so tiring.'

Although the clock starts running from midnight,

it isn't until 2am that everything is switched back on.

And then Big Ben can do its thing once more.

Now, you know me and you know that I love gadgets.

This is probably the oldest gadget I've ever seen

and it is by far my favourite. Look at it. Isn't it beautiful?

Ladies and gentlemen, boys and girls, that is Big Ben.

So, the clock face has now been turned back on

and we're now going to head over to Big Ben himself, herself,

and we're going to find out if what we've done downstairs has worked.

We've literally got a few seconds left before these dongs,

so I better get these on.

All right, here we go. Three, two, one...

BELL STRIKES

DONG!

Ho-ho. So, there you have it. Now you know why it's called Big Ben.

Not because it's big, but because it's huge and sounds amazing.

I want one.

DONG!

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