0:00:31 > 0:00:33We've travelled to Southern Ireland.
0:00:39 > 0:00:43The sea-cliffs here aren't massive, but they can be lethal.
0:00:43 > 0:00:48On the headland at Tramore, The Metal Man was raised as a warning to shipping
0:00:48 > 0:00:56after The Seahorse ran aground here in 1816, with the loss of almost 400 lives.
0:01:00 > 0:01:04Tramore is simply Irish for "big beach". Good name.
0:01:04 > 0:01:10But as we approach Waterford, things change drastically
0:01:10 > 0:01:12because Waterford isn't an Irish name.
0:01:12 > 0:01:15Nor is it English. It's Viking.
0:01:15 > 0:01:19It comes from the Old Norse, Vedrarfjord
0:01:19 > 0:01:21meaning, "the haven from the windy sea",
0:01:21 > 0:01:24signalling the first in a chain of major trading ports
0:01:24 > 0:01:30established by the Vikings in virtually every estuary from here to Dublin.
0:01:30 > 0:01:37Today, Waterford is virtually synonymous the world over with lead crystal - glass.
0:01:37 > 0:01:40And that's given Alice an idea.
0:01:43 > 0:01:47I'm just walking along the beach here picking up
0:01:47 > 0:01:52these really beautiful little water-worn pebbles of glass.
0:01:52 > 0:01:54But what is this stuff?
0:01:54 > 0:01:58I think most of us know it's got something to do with silica,
0:01:58 > 0:02:02and that it could possibly be made by heating up sand.
0:02:02 > 0:02:05But is that all there is to it?
0:02:05 > 0:02:13In the interests of science, and for the sheer fun of it, I've decided to see if WE can make glass from sand.
0:02:13 > 0:02:16Oh, and try to do it on a beach.
0:02:16 > 0:02:21If anybody's going to succeed it's going to be Waterford Crystal's chief scientist Richard Lloyd.
0:02:21 > 0:02:24- This bit?- Perfect.
0:02:24 > 0:02:27So, Richard, would any old sand do?
0:02:27 > 0:02:30It's got to have a component of quartz in it, a form of silica.
0:02:30 > 0:02:34Silica doesn't need any other ingredient to make glass other than heat energy.
0:02:34 > 0:02:36But you think this looks all right?
0:02:36 > 0:02:40- This looks fine. - Let's go and make some glass.
0:02:40 > 0:02:42This is Tony.
0:02:42 > 0:02:46- He's the man that's going to provide the heat for us today.- Hello, Tony.
0:02:46 > 0:02:48So exactly how much heat are we going to need?
0:02:48 > 0:02:51In it's present form we'll need 1,800 Celsius to melt this,
0:02:51 > 0:02:57but we're going to mix it with some potash, which helps the sand to melt.
0:02:57 > 0:03:01So how much does the potash bring down the melting point of the quartz?
0:03:01 > 0:03:03By about 600 Celsius.
0:03:03 > 0:03:07So we can then achieve melting temperatures with Tony's burner.
0:03:07 > 0:03:09so we're going to pop it on there...
0:03:14 > 0:03:17The crucible is already glowing bright red.
0:03:17 > 0:03:20Red heat is only 600 Celsius.
0:03:20 > 0:03:23- Red head is 600?- Approximately.
0:03:26 > 0:03:29- And it's starting to bubble now. - Yes,
0:03:29 > 0:03:33that's the potash releasing its carbon dioxide,
0:03:33 > 0:03:36and then it starts to react with the sand grains to form the glass.
0:03:36 > 0:03:43So, Richard, how does this from the beach relate to actually what goes on in the factories?
0:03:43 > 0:03:49Essentially, the technology underlying the things we've done on the beach is the same as the factory.
0:03:49 > 0:03:56And often this glass is talked about as being lead crystal. Do you actually add lead to it?
0:03:56 > 0:04:00We do, yeah, in a form of lead oxide. This makes it sparkle.
0:04:01 > 0:04:05It also allows the glass to be worked over a longer temperature range,
0:04:05 > 0:04:09which lets the blowers do their magic.
0:04:13 > 0:04:17It takes years to achieve this level of skill.
0:04:17 > 0:04:18Believe me, it isn't easy.
0:04:18 > 0:04:21I've just had a go myself.
0:04:23 > 0:04:28One way or another, glass has been made here for hundreds of years.
0:04:28 > 0:04:29These skills are ancient.
0:04:31 > 0:04:37This is Waterford Museum's famous kite brooch of Irish Viking design.
0:04:37 > 0:04:42Exquisite gold filigree, and the tiniest beads of glass.
0:04:42 > 0:04:45It functioned as a cloak fastener
0:04:45 > 0:04:51and was very much like the Irish ring pins that became an essential part of Viking haute couture.
0:04:51 > 0:04:56When this brooch was made 1,000 years ago, the glass beads were treated like diamonds.
0:04:56 > 0:05:01Glass was a precious, hard-won material.
0:05:01 > 0:05:03Glass is a very special substance.
0:05:03 > 0:05:06It's not like other solids, it's got no definite melting point.
0:05:06 > 0:05:10It just gets softer and softer as it gets hotter and hotter.
0:05:10 > 0:05:13It has no crystals, that's why you can see through it.
0:05:13 > 0:05:15Once the quartz has formed the glass, the molecules
0:05:15 > 0:05:18can't rotate and orientate themselves into regular patterns,
0:05:18 > 0:05:24which a crystal is, so they're trapped in irregular shapes. That's what keeps the glass clear.
0:05:25 > 0:05:27I'll get it. You clear off that way, yeah?
0:05:29 > 0:05:30Oh. Oh, wow.
0:05:30 > 0:05:32There we have glass from the beach.
0:05:32 > 0:05:39There is something really wonderful about being able to make glass from sand.
0:05:39 > 0:05:41And it's really green.
0:05:41 > 0:05:46That's because the sand we've used has got a lot of iron in it, which makes it brown.
0:05:46 > 0:05:48When it forms a glass,
0:05:48 > 0:05:50the iron changes chemically to form the green compound.
0:05:50 > 0:05:54Most of the sand in the beaches around the world will have iron in it.
0:05:54 > 0:05:57So our beaches are rusty.
0:05:57 > 0:06:02'What a great day. Not only have we succeeded
0:06:02 > 0:06:06'in making glass from sand, but the craftsmen of Waterford Crystal
0:06:06 > 0:06:11'have made something that harkens back to the very foundation of Waterford itself,
0:06:11 > 0:06:13'a Viking ring pin.'
0:06:13 > 0:06:16That is beautiful.
0:06:17 > 0:06:19Oh, Richard, that really is lovely.
0:06:20 > 0:06:24That's got designs all the way along it,
0:06:24 > 0:06:28and it's like a symbol of Waterford, isn't it?
0:06:28 > 0:06:31The Vikings and the glass.
0:06:35 > 0:06:41Leaving County Waterford, our journey continues to County Wexford, via the Passage East ferry.
0:06:41 > 0:06:44On the far shore lies Ballyhack,
0:06:44 > 0:06:49base camp for the 140-mile Sli Charman, or Wexford Coastal Path.
0:06:55 > 0:07:00Travelling up the peninsula towards Hook Head, there's a little inlet known as Herrylock,
0:07:00 > 0:07:04where beach and cliff face are made up of layers of old red sandstone.
0:07:06 > 0:07:11And all over the beach, there are these strange regular bowls in the rock.
0:07:13 > 0:07:17You could walk past this and think it was natural,
0:07:17 > 0:07:18you could just overlook it,
0:07:18 > 0:07:21think it was maybe cut by the sea or the wind,
0:07:21 > 0:07:26and if you look really closely you start to pick out strange marks, cut marks.
0:07:26 > 0:07:30These are the marks left by tools that have been used to cut something out.
0:07:36 > 0:07:41Once you get your eye in, you realise they're all over the place around here.
0:07:43 > 0:07:48Now, I'm not going to pretend that I don't why these holes are here.
0:07:48 > 0:07:52These are the remains left behind by quarrying for millstones,
0:07:52 > 0:07:54which are used to grind flour,
0:07:54 > 0:08:01and right up until the end of the 19th century, Herrylock was famous for the quality of its millstones.
0:08:01 > 0:08:08The incredibly hard, gritty Herrylock sandstone was ideal for millstones. They were sold all over Ireland.
0:08:08 > 0:08:11But how did they manage to extract the stones intact from the rock?
0:08:11 > 0:08:15To find out, I'm meeting up with local stonemason Paul O' Hara.
0:08:15 > 0:08:17- Hello, Paul.- Hello, Neil.
0:08:17 > 0:08:20Paul has a fascination with the old stonemasons' techniques.
0:08:20 > 0:08:25I'm just working on a bit of the stone here.
0:08:25 > 0:08:26What is the process then?
0:08:26 > 0:08:30How do you start with a piece of bedrock and end up with a millstone that's free?
0:08:31 > 0:08:33Well, initially you'd mark it out.
0:08:33 > 0:08:36Roughly a 4ft diameter is
0:08:36 > 0:08:41the stone that's been quarried here, then you score around your shape,
0:08:41 > 0:08:45skirting down along it, and follow the channel all the way around the circle.
0:08:45 > 0:08:48They would have gone down maybe 16 inches.
0:08:48 > 0:08:50How long will that take with a hammer and chisel?
0:08:50 > 0:08:53I'd say roughly three weeks, they would have taken.
0:08:53 > 0:08:54- Three weeks.- To take out.
0:08:54 > 0:08:56And once you've cut this gutter
0:08:56 > 0:09:00around the millstone, how do you get it off the bedrock?
0:09:00 > 0:09:02How do you get it free?
0:09:02 > 0:09:05You would bore a hole, again using your hammer and chisel,
0:09:05 > 0:09:09then fit a timber wedge, and maybe a willow timber, cos willow has a great absorption.
0:09:09 > 0:09:12The sea would have come on in, flooded the channel...
0:09:15 > 0:09:19..the timber would then expand, and the stone would have lifted.
0:09:19 > 0:09:25So as the wood expands with the moisture, that is enough force to crack this?
0:09:25 > 0:09:28That would have been enough force, yes.
0:09:29 > 0:09:33I've got a lovely picture of the actual, the scene here.
0:09:33 > 0:09:35Up beyond there was ten houses or so,
0:09:35 > 0:09:38there must have been great comradeship between them.
0:09:38 > 0:09:41And then when the conversation went dead,
0:09:41 > 0:09:43the only thing you would actually hear
0:09:43 > 0:09:47would be maybe the clanging of the hammer and the stone.
0:09:52 > 0:09:56By the late 1800s, the Herrylock chisels sang no more.
0:09:56 > 0:10:01Cast iron replaced old red sandstone as the perfect material for making millstones.
0:10:01 > 0:10:07Is it just me, but I feel a little sad this ancient industry came to an end?
0:10:09 > 0:10:11Cutting a millstone like this one
0:10:11 > 0:10:14involved some of the hardest physical labour imaginable.
0:10:14 > 0:10:17But what makes it such a satisfying story
0:10:17 > 0:10:20is that the secret ingredient was human genius,
0:10:20 > 0:10:23using the power of wood swollen by water
0:10:23 > 0:10:27to break these free from the bedrock,
0:10:27 > 0:10:29so the final tool that they had in their armoury
0:10:29 > 0:10:31was the power of the sea.
0:10:40 > 0:10:46Placid as it might appear, this peninsula has a terrifying reputation for mangling ships.
0:10:48 > 0:10:50No surprise to find a lighthouse then.
0:10:50 > 0:10:56But it's perhaps the oldest intact operational lighthouse in the world.
0:10:57 > 0:11:00In fact, historian and author Billy Colfer
0:11:00 > 0:11:03believes it dates back 800 years.
0:11:05 > 0:11:08Now this, I've got to see.
0:11:08 > 0:11:11Well, Billy, it does look like it's taken a pounding over the years,
0:11:11 > 0:11:14but how do you know it's as old as you say it is?
0:11:14 > 0:11:17- Let's go inside, Neil, and I'll show you.- OK.
0:11:24 > 0:11:29Now, Neil, if you look up, you'll get your first impression of a medieval building.
0:11:29 > 0:11:32Right, oh, yeah, it's like a castle keep or a cathedral.
0:11:32 > 0:11:36- It's so massive. - Exactly, they used castle technology to build the place,
0:11:36 > 0:11:38that's the reason for the roof vaulting.
0:11:38 > 0:11:41- Castle technology.- Exactly.
0:11:41 > 0:11:42And why is it black?
0:11:42 > 0:11:48It's black with Welsh coal, because for 500 years the light was
0:11:48 > 0:11:53kept burning mostly with coal, and this was the coal store. OK?
0:11:57 > 0:11:59The three chambers are similar,
0:11:59 > 0:12:03each vaulted. The stone vault can be seen as a fireproofing feature.
0:12:03 > 0:12:09If you have a big fire burning on top of your building, you don't want wooden floors.
0:12:11 > 0:12:17Over 500 years, that big fire to create the light meant importing thousands of tonnes of Welsh coal.
0:12:17 > 0:12:21Whoever built this place had a lot of clout.
0:12:21 > 0:12:28The first historic record of the building come from the Pembroke Estate papers in the 1240s,
0:12:28 > 0:12:34when the monks of the monastery of Rinn Dubhain are given money for the maintenance of the building.
0:12:34 > 0:12:39So, was the tower built by a monastic order, is that whose idea it was?
0:12:39 > 0:12:44No. They were financed by one of the most powerful knights in England, William Marshall,
0:12:44 > 0:12:47who controlled this area.
0:12:47 > 0:12:50Hook weather. Some view.
0:12:50 > 0:12:55William Marshall, the builder of this lighthouse, was one of the new breed
0:12:55 > 0:12:59of adventurers, really, who came to Ireland, one of the Anglo-Normans.
0:12:59 > 0:13:06He had this lighthouse constructed at this extremity of the Hook Peninsula to guide his shipping
0:13:06 > 0:13:12up Waterford Harbour to his new port of Ross, which he was determined to make into a financial success.
0:13:12 > 0:13:16So, this was a practical addition to the landscape by a businessman on the make?
0:13:16 > 0:13:21Yes, it was highly practical and functional, but it was also a highly visible symbol
0:13:21 > 0:13:28of Marshall's power and status, which became an iconic feature in the Irish landscape.
0:13:33 > 0:13:38The lighthouse's builder, William Marshall, had powerful connections.
0:13:38 > 0:13:43It was his father-in-law, Strongbow, who first landed a Norman army on Irish soil,
0:13:43 > 0:13:46just beyond the lighthouse at Baginbun and Bannow Bay.
0:13:46 > 0:13:51The irony is the Normans first came here as mercenaries, not invaders.
0:13:51 > 0:13:54They were invited. But they liked what they saw.
0:13:54 > 0:13:58They settled. And they dominated Irish history for centuries.
0:14:00 > 0:14:03Subtitles by Red Bee Media Ltd
0:14:03 > 0:14:06E-mail subtitling@bbc.co.uk