How To Recreate Livens Giant Flamethrower | Secret Weapon Of The Somme

A team of experts has gathered in northern France for a special expedition. We've got a lot of work to do. They've come to find a secret tunnel used in the bloodiest battle of World War I. It's getting more dangerous all the time. Recover a forgotten weapon of terror trapped inside it. That's it, that's it. And with the help of the British Royal Engineers... Good to go when you are. Rebuild it. It was designed to instill the most horrific terror. Good grief, that's burning my face. Mamey, France. Historian Peter Barton has come to investigate a very special field. With him, a battlefield archaeologist, Tony Pollard and Ian Banks. It may look beautiful today, but don't let this idyllic scenery fool you. This was once one of the most dangerous places on the entire planet. In the summer of 1916, this was at the heart of the Battle of the Somme. The most infamous clash of the First World War. The battle raged across this entire area, but these particular fields are very special. We've come to find a secret tunnel that runs beneath this field. Called SAP 14, it stretched from the British front line to the very edge of the German trenches. It contained explosives that could shatter German defences. A secret hatch that delivered troops straight into the enemy line. And the most terrifying weapon of the war, the Levin's flame projector. They've had real trouble getting into the tunnels. And they've taken the timber out of the incline. What is that? We've had no indication of this thing continuing on. It's around here close, but this just is not it. But the finds are coming up by the dozen. What we've found is a toothbrush. Vaseline. This is a French bayonet. It's flame projector. Is it? They found a key part of the projector. A valve that controlled the flow of oils at the head of the weapon. Once it was opened, hundreds of litres of oil would race forward, causing the machine to rise up and punch through the soil. There was nothing like it on the Western Front. The team's convinced more of it remains entombed beneath their feet. After carefully removing it from the ground, they've taken it to the finds tent for a closer look. It's really cleaned up now, hasn't it? Beautiful. We're still taking some clumps of dirt off it. We don't want to do too much to it, obviously, before the conservators get to it. It's hard to believe that it's practically 100 years old. It's in such good nick. So good, in fact, that if you look down there, and I turn this, can you see the valve moving? Opening and closing. That's phenomenal, really. After almost 100 years in the ground, which says it all, really, about British engineering. Now we've got this, it immediately asks the question, can we get any more of it? I'm hopeful that as we get into that destroyed incline, we will find more pieces. With just five days left, Tony gets back to work at the eastern incline. From the war diaries, the team's learned that hours before the Battle of the Somme began, the projector was hauled into this staircase that led to the Somme. But before it could be carried into firing position, a shell hit the incline, burying the weapon beyond recall. We've taken out the piece of the flame projector from what we believe to be the entrance of the incline down into the Somme. And just beneath, we've encountered what looks for all the world like a wood-lined floor, which is sloping down, as we would expect, down under the ground toward the sap. So, sitting on this floor, I'm hopeful that we will encounter other pieces of the flame projector. As Tony continues to excavate the incline, I check in with Peter at the front line. They came in search of the sap and flamethrower, but couldn't resist excavating a stretch of this iconic trench. Peter, this is such a neat piece of archaeology. You've got the First World War trench there, and then, obviously, it would have continued in that direction, and here, and over there. What does it tell you about what life would have been like for the people who were guarding the front? It's a deeply evocative piece of archaeology. Here, we have an armchair. It's only a sandbag to us, but it was an armchair to the old soldiers. This is the only place you could sit in this trench. There's nowhere else to go. You'd have your feet inspected, you'd have your rifle inspected, you'd receive letters from home, you'd write letters from home, and you'd wonder when this damn war was going to end. So, this was like their home, really, wasn't it? Yeah, this was your home. You kept it clean, and you knew this as well as your home. Here, for instance, you've got petrol tin. Wouldn't have carried petrol like that. It would have carried water. That's the only way you could bring water into the trenches. It very often tasted of petrol. Down here, you've got... That's a tin of jam. Probably plum and apple. Yeah, astonishing. Tiny little slice of life. But a tiny little slice of thousands of lives. Back at the eastern incline, more of the flaws revealed. Our piece of flame projector was on this step, at the top, on the level. Now, I would imagine, looking at the angle of this, that anything that was put on this, there's a good chance it's going to roll down the chute. So, we may have, at the bottom of the incline, I'm not quite sure how deep, a whole pile of flame projector parts. So, what we've been doing is we've brought the machine in, and we're trying to catch, at a deeper level, the incline coming down. But Tony's got another reason to be excited. This is now looking like our best bet to get down into the sap. Just keep our fingers crossed. With a key piece of the projector recovered, the team starts the second part of this remarkable project. We don't know what this thing looks like in action. And I think, to complete the circle of this story, it would be great to be able to see this thing actually firing, or something which resembled it actually firing. To kick-start the rebuild, Peter travels to Chatham, UK, home of the Royal Engineers. Today's generation of Royal Engineers come to learn how to clear minefields and build bridges. But in 1916, the curriculum contained some very different lessons. When they weren't learning how to dig trenches and tunnels, they trained with poison gas and flame throwers. Almost a century ago, the inventor of our flame projector walked these very grounds. A recent Cambridge grad and brilliant engineer, his name was William Livens. What do we know about Livens? He joined up on the very first day that war broke out, and said, I want to get into action. But he didn't get to do that, unfortunately. He came here, to REHQ in Chatham, where he was stuck in a signalling section. So he was just a kind of glorified messenger, really? Sort of, yes. Sending messages by motorbike here and there, or by telegram. And he was desperately frustrated. So what was the tipping point for him? Well, that happened on May the 7th, 1915, and that was the sinking of the Lusitania. And Livens thought that his fiancée, Elizabeth, was on that ship. He checked on the passenger list, and there was her name. So he believed that she was one of the 1100 who'd gone down with the ship. And at that very moment, he swore that he would kill as many Germans, personally, as civilians that had gone down on that ship. Three days later, he got a telegram saying she'd missed the boat. So when he found out she was still alive, did he withdraw that vow? He didn't. What was his plan to kill all these people? In one of these rooms around this square, he starts experimenting with poison gases, and flame projectors, of course. News of his inventions quickly spread. And in time, the 25-year-old was put in charge of Z section, a secret unit tasked with building flamethrowers. The prototypes under development were death traps, just as likely to burn operators as intended targets. Convinced he could do better, Livens began to build the deadliest flamethrower in history. Unlike earlier models, this one could be secretly fired from a tunnel. 20 cylinders of compressed nitrogen forced the fuel towards the front of the machine. As pressure built, the monitor head rose up and punched through the soil. Torches lit the fuel as it left the nozzle. The result was a weapon of unimaginable terror and power. Now, with the help of the Royal Engineers, we'll try and make a working model in some of the very shops Livens might have used in 1916. To get started, Peter and Tony first pay a visit to the Royal Engineer who'll be leading the rebuild of the flame projector. Staff Sergeant Steve Boylan. Steve, how do you feel about building a working model of what we found? Some of those pieces seem incredibly complicated. Are you intending to rebuild those? No, Tony. The parts we found were absolutely amazing. We're going to hopefully use modern components. It's quickly deployable, a lot lighter, but will still do the job. What kind of propulsion system are you going to use? We're going to use a centrifugal pump that'll be driven by a diesel engine. It's a lot safer and a lot easier to control and manage. It sounds like this is the opposite of what you normally do with fuels. We spend 99% of our time trying not to set alight the fuel, but this one's going to burn, I'm sure of it. And after all, Peter, we are the Royal Engineers. We can do anything. As Steve gets to work on the machine, Tony and Peter head back to site. They now have just days to finish the dig. At the eastern incline, efforts to find more parts of the projector continue. That's hollow. Gary, can I come down? Of course you can. There is a little void underneath. What they thought was the floor may in fact be the roof. It's outside. There's a wall here as well. If part of it's still intact, they may have discovered a time capsule from June 1916. Oh, that's rope. It is, it is. Rope. The head of the monitor was lifted with rope. Do you remember on the photograph? It had pulleys. In case the hydraulics failed, the monitor head could be raised with a pulley. That's a great time. We've got some digging to do, haven't we? Yeah. They've uncovered the shattered top of the structure and are crossing their fingers that the rest of it's beneath their feet. With the help of the Royal Engineers, they start to uncover the incline. The epicentre's somewhere here. The chap's filling the burrow faster than I can move it. What they find is astonishing. 30 feet of shell-blasted roof and walls. A very nice job, boys. They hope more of the projector will be trapped inside and that it might finally lead to the sap. Well, this is really exciting. And look how it's twisted. It's just like a big roller coaster. It's tremendously steep. I'd rather be carrying a flame projector down it than bring it back out again. We've got a lot more work to do in here. We're nowhere near the bottom yet. As work continues to uncover the incline, I head over to the finds tent. The finds are really starting to come up now, aren't they? We've got some really nice little insights into what they were doing in their downtime. Much of it appears to be related to alcohol, which is something that, as archaeologists, we can understand fully today. We've got a Johnny Walker whiskey bottle here, which was a real favourite of the British soldier, a bottle made in Kilmarnock in Scotland. Cork's still in it. We've got a French Pernod bottle. And let's not forget we've got both French and British on this site, French first and then the British taking over. And I think my favourite is this champagne bottle, which shows some degree of high living, which still has the label visible on it. What about the smaller finds, Tony? Well, this is lovely. This was in the frontline trench and it's a daddy's sauce bottle, brown sauce, which is still my sauce of choice. So men sat there overlooking the Germans and slapping this stuff on their bully beef. Then we have a beautiful little inkwell, which is very emotive, I suppose, brings to mind the image of the soldier writing letters home from the frontline. Beautifully made and it's got these little grooves in it and the reason they're there is you can simply rest your pen. What's that intriguing little thing? Well, this is actually my favourite find from the entire dig, believe it or not. And it came from the incline entrance and it's a little love heart carved from a pebble. And some soldier, whether he intended to give this to his girlfriend or wife or whatever, lost it. But a beautiful little thing and brings to mind so many other things than war. With just four days left, efforts to find the bottom of the incline continue. They hoped it would lead into the sap, but after chasing it for 40 feet, it's not looking good. That's the end. That is the end. So there's nothing, no more timber beyond there? No more timber. They've recovered everything from here. It looks that way. Everything except for this incline has been stripped by the tunnellers and the saps caved in. Everything they could get into, they've robbed. One part of this project has come to an end. It is disappointing not to be able to get into the original galleries, the original tunnels. But another is still very much alive. We do have much, if not all, of our eastern incline, which presumably within it may well have more of our flame projectors. It's folded up like a book as the explosions knocked it through, so anything that was in that incline is still in there. But the team's been given one more chance to get a glimpse of the tunnellers' world. Word of the dig has spread, and we've been invited to Busancorn, a village 12 kilometres north of our site. During the war, tunnellers expanded medieval catacombs that run deep beneath this church. Sealed off for years, the team's been given special permission to enter. Armed with a mechanical canary that will monitor oxygen levels, they head off into the world of the tunnellers. It's like a concrete bunker, there's stuff. I've no idea how deep it is. In the weeks before the Battle of the Somme began, allied soldiers took refuge here. Far below ground, they were safe from German shells as they waited to enter the battle. At the edge of the catacombs, they reached the point where the tunnellers would have begun their work. These chambers were carved through hard rock common to this region. Although our sap was dug through clay, this is what most of the tunnellers working on the Somme would have faced. Look at this. Inscriptions and all sorts on the side here. Loads of graffiti. There's graffiti everywhere. There is. 1960. It's everywhere. It is everywhere. There's a Canadian machine gun company here. Canadians? Corporal S.R.C. Brooke, 436128. First Canadian machine gun company. Later, McMinnville, I think. 1916. That's amazing. Absolutely astonishing. Everything beneath the grass is frozen in time. Everything. Look at this. Is it a bed? Very probably, yeah. Shall we go through here? It just goes on and on and on. Helmets were a good idea. A pair of boots. Wow. Is that archaeology? No, it's history. I know we didn't get into our own, but coming into here is just special, isn't it? It's a time capsule. It leaves you breathless with admiration for those men, doesn't it? Always digging through this stuff. That's 24 hours a day, 7 days a week. Amazing. But they had to do it. They had to be ready for the 1st of July. Although they didn't get underground on site, they've managed for a few incredible moments to walk in the footsteps of the tunnellers. Back at the site, the hunt for more of the projector is in real trouble. Last night, the area was pounded by a ferocious storm. Oh, dear. Yes, quite a turnaround. Well, in there, we reckon there's about 3 foot of water. That's good. I'm wearing the right boots for this. So the site really today is unworkable. And it's Wednesday today and we've got to be out by Friday. Definitely got to be out by Friday. There are no options there. We still have some key tasks to do by then. What's key? What's vital? What do we need to have done by the time we go? The key task is getting into that incline. We've exposed it very carefully. We hope within there we're going to find more evidence for our flame projector, but we need the conditions to be able to do that. As we wait for the site to dry out, I head back to Chatham to check in on the rebuild. Steve and some of his students from the Royal School of Military Engineering are about to test it with water. This really is quite a big moment for me, because everyone has spent so much time and trouble researching the flamethrower and they've pinned all their hopes in it. And now, for the very first time, I can see it. Steve! Hi Tony. Wow, this is something, isn't it? Thanks very much. I'm glad you like it. I didn't say that. I said it's something. It is something, yeah. The one thing that strikes me is quite what a large area it all covers. It certainly is. It's our first trial with the bits and pieces, with the water, and we've got a few things here we might not actually use on the day, but we're going to trial a lot of it, see what works best, and then move that forward for the final shot with the fuel. So what is it that you want to try and find out today? It's the first time all of this has been put together like this. We want to see that it works, we want to see that it pumps, we want to see that it produces pressure. Peter, come over here for a minute. This is your baby. How are you feeling? I'm just delighted to be working with people who know exactly what they're doing. I mean, this is an absolute monster. Yeah. Living's machine was powered by compressed air, but our rebuild will be driven by a massive diesel engine. We've got a big mechanical pump here, basically. This is what's going to take the fuel, it's going to suck it out of our tanks, it's going to move it through the pipes and the valves, and it's going to move it onto our larger pump there. We're going to bring it all out from these tanks here, basically, one at a time. So these four tanks will hopefully represent our four shots. These bags will soon hold fuel. Today, they're filled with water. 2,000 litres of it per minute is about to be sucked from these bags and thrown towards the nozzle at 15 metres per second. Are we ready to go? I think we're ready to go, Tony. We're certainly ready for our first shot, if you want to see what it looks like. Let's go for our first shot. I'll get the other way. With the all clear, it's time to see this thing in action. First heat in the air. Yeah, we're getting slightly showered here, aren't we? We're mooring to a quite strong headwind in a minute as well. A matter of seconds. That's going to give off some flame and some heat. Even though we weren't in the direction of the wind, we were still being covered with a lot of spray. Imagine how dangerous that would have been to the lads behind it. Especially feeling that mist on your skin. If that's oil or flame, it would have been horrendous. It really would have been. With the fuel, it's going to be absolutely essential that the wind is in the right direction, otherwise we're not going to be able to use it at all. Certainly, and that's what we want to avoid on the day. But you're going to have a fiddle with it? We're going to have a fiddle, a tinker with it and see what we can do. Well, as tests go, it wasn't bad, but when I come back, it'll be the real thing. When we left yesterday to check on the rebuild, the site was a mess. The team believe that more of the projector can be found at the bottom of the incline, but to get inside, they need to remove the water. Gary, why have you turned the pump off? We've got to a point where it's just slurry. So rather than clog the pumps up with slurry, what we're going to do, we're going to form a human chain and just bucket this out so it's out of our way. So, with just two days to go, they decide to roll up their sleeves and get a first-hand taste of the infamous mud of the Somme. Now we're cooking on gas. And so we've resorted to the old bucket line. Try not to kill him, Kel. Try not to kill him. The chain's broken down for some reason. It's broken down. We'll just send all these empties down now. You sound like you're in the pub, Pete. Send all the empties down. A few more, chaps. OK. Well done. Put a bit of colour in your cheeks. Well done, big fella. Well done, Kel. It's back to the university for me. As we prepare for the final push, Peter and I head to the end of the sap. By July 1st, 1916, it was over 100 metres long. We've taped out the line of the sap, and you can see it comes right to the German line. So beneath our feet here, there would have been two board mines, and they were blown on the moment of zero, 7.30am, 1st July 1916. And what was the effect of that? It blew in two German dugouts, possibly containing machine guns, a sniper's post, and it would have wrecked their front line completely. So what it really did was neutralise this part of the line. Immediately after that, from this point here, out popped a party of men from the manhole and went straight into the German trenches. So anybody in other dugouts coming up will see there's British soldiers here. What can you do? Were there many casualties? The company who attacked from our line over there, a minute and a half away across No Man's Land, had no casualties at all. This seems to fly in the face of everything that we've always learned about the Somme. Was it a fluke? Well, it appears that wherever the SAPs were used with ingenuity, there is a correlation between success and the use of SAPs. So all the way down the south here, where they had clever and intelligent use of the SAPs, flamethrowers, mortars, machine guns, mines, they gained all their objectives. Elsewhere, nothing. By the end of July 1st, the Allies had grabbed the German front line and raced deep into enemy territory. For the first time since the war began, the May was in Allied hands. To the east, attacks were launched from almost a dozen SAPs driven by the 183. Peter has learned that this is where the Livins flame projectors saw action that day. Hours before the battle, three were hauled into SAPs. Ours was struck by a shell, but the others made it into position. Just on the ridge over there, where the two trees are, they managed to get two in use. At 7.30am, Livins' creation made its terrifying debut on the Western Front. It was really instilling dreadful terror. The machines worked, and the German line was hammered by a terrifying wall of flame. Once that flame was burning across here, it drove the Germans into the dugouts and when they came up again, the trenches were full of British troops. Within hours, kilometres of enemy territory and hundreds of Germans were in Allied hands. It was one of the most successful operations of the war to date. Following the battle, Horace Hickling, the architect of the tunnelling scheme, posed with his men in captured German equipment. So what Hickling put into place here to assist those men was totally unexpected. That's the key. Surprise, surprise, surprise. But it seems to me that you're making a big assumption, which is that the difference was the SAPs. But there must have been other factors at play. Were there less Germans on this part of the line than elsewhere? Yes, that has been said, but that of course begs the question, why invest so much time, effort and ingenuity in a place where you think it's more weakly held? Why not place it somewhere else? Why not put it at a massive strong point further north? As evidence, Peter points out the fate of the 9th Devonshires, an Allied unit that went into battle to the right of our field. Despite attacking along the same stretch of front, at 7.30am they were torn to pieces while trying to cross no man's land. The key difference between their field and ours, no SAPs. But Peter believes the most tragic misuse of the SAPs occurred in the northern sector of the front. Over 3,000 metres of tunnels had been driven in the weeks before the battle. To learn more about what happened here, Peter and I head north to visit the battlefield near Sare. We must be, what, 10 miles away from where we're excavating. Were there SAPs all the way along this line? There were, we are 10 miles away, exactly, yes. And there were SAPs everywhere, all the way from our site to this point here. We're in front of Sare, and this is the northern boundary of the Somme battlefield. And what happened here? Probably the worst disaster of the entire battle. There were SAPs here for the infantry to use, but they attacked over the top. Those SAPs were not planned to be used by those troops. The front line was not captured, and no man's land was a carpet of British dead and wounded. It was a disastrous day. I don't understand. Why was the decision made not to use the tunnels? It seems that the choice was the divisional commanders. And the commander here thought that the artillery would do the job for him. So he said, right, we will use these tunnels, but only after we've captured the German front line, and then we can use them for safe communication. So he didn't put into place any mines, no machine guns, no flamethrowers, certainly. It's ironic, really, isn't it? All these guys were coming out of their trenches, and underneath their feet was their salvation. That's absolutely right. They could have used those tunnels with a bit of thought, with a bit of communication, with a bit of ingenuity, with less confidence in those guns. They were there for them. It's a tragedy. The disaster was repeated throughout the northern sector of the front. Within 24 hours, 60,000 men were dead or wounded. Among the hardest hit, the 1st Newfoundland Regiment. 780 men went into battle that morning in this field just south of Serres. 68 reported for duty the next day. After the 1st of July, what happened to the whole notion of digging tunnels under the no-man's land? They took it up immediately. By the 3rd of July, they'd already put into place schemes for more SAPs, a hell of a lot more SAPs, on the places where they'd not made any gains. And I'm talking about quadrupling the number. So they instantly realised the mistake they'd made on the 1st of July by not using them properly in the north. In the next battles, in 1917, at Vimy Ridge, at Arras, at Messines, they put in massive Russian SAP schemes in order to achieve exactly the same as they wanted to do here on the 1st of July, to help the infantry get into the first line of German trenches and move on from there. As day 14 comes to an end, they've now got just hours to get inside the incline and find more of the flamethrower. The entire project has come down to the wire. At the bottom of the incline, the team is ready to start removing the timber in hopes of finding more of the projector. So you've got the sling round it now? Yeah, what we're going to do, we're going to try and see if we can sort of extract it like you would a tooth, you know, pull it straight out. Hey Gary, do your worst. Come on you devil. I'm not letting you anywhere near my team. He's coming now Gary. No, he's got it, he's got it, he's got it. Lift, lift, lift, lift. Oh, fantastic. As they remove more timber, they spot a void in the clay. What is it Gary? Is it metal? It's quite substantial. It's about 8 to 10 inches wide in diameter. Looks like it could be a tank. Oh boy. It could be the firing tube. There were seven of those. It sounds hollow. Gary, do you think you're going to have to extend that hole or do you think you can get it out as it is? We're definitely going to have to extend the hole and there's a flange on the end of it. There's a flange right on the end of it. Exactly what we want. He knows it's correct, he can feel it. He's never felt one before. Nobody's felt one for 90 years, Tony. Peter hopes they've found another key piece of the machine, a firing tube. Where they actually held the fuel and the piston pushed the fuel through it into the firing head. If we have got what we think it is, that's going to make the whole dig worthwhile, isn't it? But there's a catch. The reins destabilise the banks and they can't risk digging here for long. They've given us a bit of concern on this side, so we don't want to waste too much time. Be careful, mate. With time running out, they launch a final effort to retrieve the piece. It would be fantastic to get that one out. Thanks, chaps. Nicely done, sir. It's like an ancient cannon coming out of the seabed. Give him room. That's it. Set it there. Can you identify the part? I can. Part number 321. Projection pipe. Plane. How are you feeling, Tony? Amazing, really, given what we faced this morning. I never thought we'd get here. It's incredible. Well done, Pete. With the artefact out of the ground, there's just one last job to do. Royal Engineers, come on. And the honour is given to a very special part of the team. It's rather touching, that. Ninety years ago, Peter Setters brought that through the trenches and carried it down. And now it's Royal Engineers, in 2010, carrying it out. Makes you feel rather tearful, anyway. It really does. As day 15 comes to a close, it's time to end this remarkable excavation. As far as I'm concerned, that's mission accomplished. We've got various pieces of the machine. We've exposed and recorded the structure. We understand what's happening with it as far as we can. So as far as I'm concerned, I do not see the need to go into that any further. Don't you want to get further in, Peter? I'd love to, but I agree with Tony. I think we have found what we need. And we've come up with the goods. We have found the parts of this extraordinary, unique machine. They may exist nowhere else on Earth. With the excavation over, it's time to head back to Chatham. For the first time in history, we'll try to fire a rebuild of a massive First World War flamethrower. As the dig continued, the Royal Engineers have been hard at work on the rebuild. While they've never used such a horrifying weapon in battle, it's finally ready for the test range. It's a lot of work done into it though, isn't it? It's much bigger than it was before. This construction is very sturdy. Thick, heavy pipe, an I-beam behind it, and we certainly don't want this to move. So how are you going to ignite the fuel as it comes out through the nozzle? We've got two welding torches and we've got the flames crossed, and we're going to fire the fuel through them flames. You've got a new nozzle as well. That's tighter, is it, than the other one? Yep, we've got a nozzle on there. It's very true to Levin's original system. We've copied his original one, and hopefully it'll do the job. That's the valve then, Steve. That's the fast-acting shut-off valve, yeah? Yep, that's the fast-acting shut-off valve. It's very key. It's operated by air, and its job is to slam shut the supply of fuel. Also to open it, but it's a key piece of equipment. This dead man's switch is critical to the team's safety. After each firing, this valve will be slammed shut, instantly cutting off the fuel. This should keep the flame from travelling down the pipe and igniting 5,000 litres of fuel. If it fails, the entire site could go up. But it's just one of the problems Steve's facing. I'd be embarrassed if we can't set a light to it. If we can't ignite, a lot of care is in the welding torches. We haven't done our job. So, sleepless nights for you, then, for the past few weeks? I've got a bet on it. I'm confident it'll go, but that would be my biggest worry, it doesn't ignite. Good luck. Go ahead and gate, Gordon. Can you please close the gate? Over. After all this work, the team's anxious to see this thing in action. This is from gate, Gordon. Gate closed. Over. But once again, Mother Nature's refusing to co-operate. This wind must be quite on the edge. The wind's picked up, and if it gets any worse, they'll have to cancel the test. But that's the thing about these weapons, gas and stuff, the wind's got to be in the right direction, all the conditions have got to be right. Finally, as it dies down for a moment, Steve decides to go for it. What are they using here, oxyacetamine torches? Yeah. It's a very, very peculiar feeling to be here. It's been in my head day and night for years. It's as if everything up to now has been academic, and now it's become something very different. Steve hopes these torches will ignite the fuel as it rockets from the nozzle. I can feel my blood pressure rising. But he's not sure if it'll work. The jet of fuel may simply blow the torches out like candles. To increase his odds, Steve's decided to go with a shot of pure kerosene. It burns easily, but there's one drawback. At this volume, it may turn into a giant ball of burning gas, and not a controlled burst of flame. With this valve open, there's no turning back. Here we go. Step back, Tony. That's exactly like the photographs. God, that is horrific. That is horrific. That's burning my face. Even at a safe distance, the heat's tremendous. We've burned up the world. Good Lord. Exactly like the photographs. Oh, God. That's some love. Brings tears to your eyes, doesn't it? That was very uncomfortable. That is horrific. Incredibly, it's worked. But now they want to see if they can get it closer to the real thing. In 1916, Livins added diesel to his fuel. The diesel's in there to give it extra thickness and carry, and also to make sure it stays alight when it reaches the German trenches. So some of it's alight as it's going over there. It lands in the trenches, and then it catches fire, so whoever's in the trenches. If they can get a mixture of diesel and kerosene to ignite, this is as close to the original as anyone's ever going to get. OK, Clark, you're good to go when you are. With the added diesel, the results are even more incredible. That's getting afterburn with the gas. That's really igniting, isn't it? Yeah, it is. I've got my eyebrows. Dear God almighty. Wow! Just a bit of extra diesel, you see what that does? That's exactly what he wanted to achieve in 1916. Anything the oil landed on which would burn, would burn. Well, everything is. There's no escape from that. My lips are burning. With the test a success, it's time to dismantle the projector forever. Well, I think the sappers should be very proud of themselves, don't you? Amazing. I'm surprised by the actual heat coming off of it. It is quite a frightening object. I think one of the lessons we've learned this afternoon watching this firing is how effective this weapon would have been. We've seen through the archaeology how good the trenches could have been at protecting you from machine gun fire, and even to a degree from artillery. But the thing with the flame projector is it's delivering flame down on top of you and what is supposed to be a means of defence effectively becomes a death trap. For Peter, it's given him a first-hand view of a war he's only seen in photos. The most impressive thing was to see a moment in time, or a few moments in time of the First World War in colour. And that's what we've got here today. Every image you look at is black and white, but today we can replace the colour in those amazing archaic images. We can see exactly what this weapon would have done. It's also highlighted the engineering feat pulled off by the machine's inventor, William Livins. Within 25 weeks, it's gone from the page, the first pencil sketches on a page to being deployed on the Somme. So that's devising, designing, building, testing, training, transporting, rebuilding and using it on the 1st July 1916. That's an unbelievable achievement. But despite its performance on July 1st, his invention would be used only twice more in battle. As the war grew more mobile, his massive projector became obsolete. You needed very specific conditions to use a weapon like this. The front had to be static and once it started moving forward, there was very, very few opportunities. The advance had to stop for you to reuse it. As the war dragged on, Livins continued to develop weapons. In 1918, three years after making his vow to avenge the Lusitania, he returned home to his wife. He didn't stop designing, but one of the most bizarre things about this really bizarre life is the next thing he designed was nothing to do with weapons. It was an electric dishwasher. We came in search of secret tunnels. But in the end, we found so much more. After moving a mountain of dirt, we stood in the front line of the Somme, found key pieces of a top secret weapon, and for a few moments saw the First World War in vivid, terrifying colour.