The Infinite Monkey Cage - What a Gas! - Dave Gorman, Mark Miodownik and Lucy Carpenter

Episode Date: August 7, 2024

Brian Cox and Robin Ince talk hot air as they explore the pivotal role of gasses in our lives. Joining them to add some Co2 to the mix is material scientist Mark Miodownik, chemist Lucy Carpenter and comedian Dave Gorman. They discuss how humans came to even understand it existed in the first place as well as how many of the innovations in modern society have been underpinned by this mostly invisible and odourless substance. We laud the humble (or is it noble) gas and its key role in technological innovation - from using laughing gas in anaesthesia to the combustion engine and of course the most important of all, the power source behind squirty cream. Producer: Melanie Brown Exec Producer: Alexandra Feachem BBC Studios Audio production

This is the BBC. This podcast is supported by advertising outside the UK. It's summer in Britain and the crimes are just getting started. I found another body. Stream the best of British crime drama only on Britbox. Don't miss new seasons of acclaimed series like Blue Lights, which Time Out calls Belfast's answer to the wire. Back up, back up Ivan!

And The Responder, starring Martin Freeman in his international Emmy award-winning role. I can feel it, I'm gonna crack. Stream the best of British crime drama on BritBox. You know this is why I want to be a detective. Watch with a free trial today. BBC Sounds, music podcasts I'm Brian Cox I'm Robert Ince and this is the infinite monoxide cage yeah that's right we are now the infinite monoxide cage formerly the infinite monkey cage which of course people will be very glad that we've changed it because everybody's go the infinite monkey cage is so cruel to

the infinite monkeys yeah they say it's infinite. You should have to understand that. So it was really cruel about an infinite. We've got rid of the monkeys and... Ah-ah! Shut up. And instead we fill the cage with monoxide. And apparently it's absolutely fine. If you hurt monkeys, that's against BBC rules.

Killing their presenters is absolutely fine, because they're just humans. Even though Brian technically is not a human because I made him Anyway today we are joined by a compound of chemists. No, it's a saturated solution of chemists. Where is the well? Let's collect. Let's find a happy medium for this medium I didn't say some wouldn't be nice. Thank you very much Let us call them an assembly of alchemists and they are here to discuss one of the deepest but also lightest philosophical questions We've ever approached here on the monkey slash monoxide cage. What is the gas? Yeah, what is the gas?

I've done a lot of research actually because before this I thought how do I best research gas? So I watched a documentary all about Monsieur Petter main, who some people here will know about Monsieur Petermaine, who was a French music hall performer who found a way of using his internal gases to then create tunes with his bottom. I know, and QI don't have me on. Ridiculous. To discuss this and other fascinating facts about gases we're joined by a chemist a material scientist who aren't Dave Gorman and one Dave Gorman who is Dave Gorman but he's not a chemist or a materials it's complicated. I would have just gone with we're joined by two not Dave Gormans and one Dave Gorman

I think that would have got us there a lot quicker. We're joined by and they are! My name is Mark Miodownik I'm professor of materials and society at UCL and the gas that I would least like to be stuck in a room with is methanthiol and this is a farty foul-smelling gas that is partially responsible for bad breath but it's intentionally added to methane, the methane that goes into people's homes for their central heating and their hot water and it's added to methane, the methane that goes into people's homes for their central heating and their hot water. And it's added to that so that you can smell a leak. And it is horrible. And if you're in a room with it,

you either think there's someone in here with terrible breath or there's a gas leak. Both are bad. My name is Lucy Carpenter or Lucifer to my friends. I'm a professor of atmospheric chemistry at the University of York. And I specialize in gases in the marine atmosphere, so far away from pollution. And my gas has similarities to Mark. It's a sulfur-containing gas as well. So it's dimethyl sulfide, or DMS. In low concentrations, it's attributed

to the smell of the sea. And it's also beneficial to the marine environment. In the atmosphere, it has oxidation chemistry and helps make clouds more shiny, scatters sunlight back to space But at high concentrations it smells of cabbages, and I'm not a fan of cabbage you smell so I don't like it My name is Dave Gorman. I'm not a scientist, but I'm here because I won a competition and The gas I would least like to be in a room with is jumping jack flash Now mark you've written a book about gas it's called it's a gas why I

Just think gas is a form of matter that is really underappreciated like it's mostly invisible It mostly doesn't smell of anything and you mostly just don't even notice it's there. It's kind of all around us, it's responsible for the birth of all the planets and all the universe but it isn't appreciated enough and it's in all our lives, in fact it's our life support system. If you go to hospital it's part of medicine, it's obviously part of the air we breathe, it keeps the climate and us alive in terms of all life on the planet and also, and let's not forget breathe, it keeps the climate and us alive in terms of all life on the planet and also, and let's not forget this, it's responsible for the bicycle being as brilliant as it is and bicycles are amazing and they are amazing because of gas.

I object to you saying that gas is irresponsible for the birth of the universe. I knew it, I was baiting you. I'm glad that Mark mentioned bicycles though because one of my favourite gigs I did was him. It was at the Royal Institution where he decided he would enter by riding in on a penny farthing, but failed to check the height of the door before doing so. LAUGHTER Dave, sometimes it's quite hard to get the guest in. And initially I thought getting in a kind of non-scientific guest on gas, you know,

it's going to be difficult, but I don't think it is so Dave did you have a soda stream when you were a kid? I did actually and I very much enjoyed a soda stream I also I feel like this is a topic I've got input in like many people I've got I've got a young child which means like many households gladiators the reboot has been really big In our house and we had a conversation which I imagine millions of homes up and down the land have had which is what would Your gladiator name be if you were a gladiator and it was universally voted by my family that mine would be wind Lucy we should start with the definition. So what is a gas?

A gas is basically a material that has a lot of energy. So it likes to be separated from its other molecules, unlike solids or liquids. Although having said that, if you take a cubic centimeter of air, you've got around 10 to the 19 molecules of gas in there. Because they're invisible, we can't see them. Most of them don't smell either. But the essence of being a gas is you don't like your neighbours really, you want to be separate from them and exist because you've got your own energy going on,

you've got your own kinetic energy. So unlike in a solid and a liquid where the molecules are attracted to each other, so that's where they stay. So they're excitable creatures. And what's the difference between a vapour and a gas? Because you say vapour, don't we? We do say vapour. I feel like a vapor is a sort of old-fashioned term for a gas or maybe it's a gas that you can see so a

cloudy so something that is maybe has particles in there as well so if you have maybe small water droplets you'll be able to see them because they're going to scatter light. But there is that thing about vapors that they are condensable aren't they? So the reason why you can smell perfume is because a vapor comes off the liquid but the liquid is still also a liquid so where a gas and liquid both inhabit the same space that's what you're smelling is the vapor whereas these little particles of actual liquid they're an aerosol I think aren't they? They are a liquid phase in the gas, in the air,

as is a cloud. A cloud is these tiny droplets of water. And so when you look at the sky, the things you notice are these little droplets. The liquid phase, actually you don't notice the gas phase. And again, why do we not appreciate this enormous volume of gas, 100 kilometers high, the atmosphere? And we're at the bottom of this sea of gas, 100 kilometres high, the atmosphere?

And we're at the bottom of this sea of gas, and this is called atmospheric pressure. And it has shaped our history, it's shaped our evolution, but because we were born at the bottom of this sea of gas, we're used to it. And then we don't notice when it does strange things. But it is responsible for lots of our gas technologies, like the steam engine. I can answer your question as to why it's underappreciated though. It's because we can't see it, hear it, touch it, feel it, or smell it. So we don't know it's there.

So of course it's underappreciated. It's invisible. But I... Sorry. So I was going to say, Mark's comment about it being so thin, I mean, when you see the images of the atmosphere from space and it looks just like this tiny thin layer, it's what, 100 kilometres thick, so you could drive out of it in an hour if it was horizontal and yet it has all these amazing functions for us. So keeps us warm,

protects us from UV radiation, gives us oxygen to breathe, all of these functions that we don't even realize because they're just happening around us and not not visible. Yeah it does raise the question when did you say it's underappreciated? But historically, when do we start paying attention to this invisible atmosphere? Yeah. And trying to describe it, trying to understand what it is.

So the ancients thought that the world was, and I actually did go to a school where they taught me this as the truth, which is another story, but there are four elements, earth, air, wind and fire. No, no, no, no, no, no, no, you can't get out of it. I think we do need to know what the truth was from the ancients before we move on to gas.

My parents joined a religious sect for reasons that I can't really explain, but they then put us in the school of the sect and the first chemistry lesson I ever got was there are four elements, earth, air, wind and fire. And I was impressed about the air one because I was like, what is that? It was the one I was least familiar with and despite the fact that actually there are not just four elements. But I think that's where it kind of seems common sense that there are these different types of matter and we'll call them the fundamentals.

And the gas, you can feel air when it comes into your lungs. So that is where you understand and you understand that people die when they don't have air. But it took a long, long, long, long time to understand that air is a mixture. So air was thought to be a pure element. And then there's the other element, the fifth element, which is sort of related to gas, which is quintessence or ether. And this is the element that was meant to fill the rest of the universe. So Lucy talked about this thin layer of gas around our planet

They understood that there was an atmosphere and there was something else that the stars Inhabited and that was a fifth element the pure perfect element and that's quintessence or ether and it took a long time to understand And it was the astronomers who really nailed the fact that ether Hmm couldn't really be a gas actually Because they started studying the stars. So this is the first beginnings of us understanding of gases and and what goes on It's the beginnings of chemistry. Yeah, so when do we start seeing an understanding of this? Yeah is not just a fundamental. Well, I think absolutely right was it priestly wasn't it? So he under turned basically 23 in interrupted centuries of of dogma which was that air was one I mean imagine that

as a scientist if you wrote the papers I've discovered something that hasn't nobody's discovered for 23 centuries because he discovered that in fact it was a composition it wasn't some intangible indestructible element of just air I think he did experiments with mice correct me if I'm wrong so he maybe did some things that maybe not have met the scrutiny of today's experiments. They all did those in those days, they did not fill in ethics forms at all. No, they didn't do their health and safety, but I think he used to put upside down beakers and then I think with the thing with oxygen, there was a mouse in a jar with

also a piece of wood, so if he discovered that whatever it is that made the flame happen, which was oxygen, also kept the mouse alive and he did the control experiment where the mouse did not stay alive as well but with that came the discovery of oxygen and the air was not just some intangible thing but actually had composition and was made up of lots of different elements. So it burnt the wood to take the oxygen out of the jobs and then notice that the air the the air was still there But the mouse wasn't the mouse wasn't not not in its living state. Anyway, I mean what an experiment I don't think that's proved that oxygen is a thing. I think that's proved he's barbecued a mouse

Set the mouse on fire that he was it was separate from the Wasted the mouse on fire, it was separate from the flame. Then he wasted the mouse, didn't he? It looked like marshmallows on him. Priestley also didn't believe that he had discovered oxygen. He was investing in phlogiston. So the reason why things burned wasn't that they reacted with oxygen, which we now know to be true, and actually his discovery was the one that really turned it.

But he thought that, and as did everyone else, that only things that burned, they gave off phlogiston, and that went into the air, which was this element that could take phlogiston and then and then plants absorb phlogiston and they became wood and then you could burn the wood and it gave out the phlogiston again so the idea what combustion was what the magic for flame was if you think about the most magical gas it's a flame in a way isn't it like it it captivates you you can look at a fire for ages and and and they thought this was a substance right and it was this phlegistin that was was

responsible for the flame of a candle the flame of a fire and and he came across evidence that it was not it was an oxygen in the air and it was the same oxygen that we breathe and he still disputed it till he died he he said no it's phlegistin and it was other scientists who said, hey, you just don't know how good you are. You really should just take credit for oxygen. You should do that in a French accent, like what you just did.

That's right. It was a voice, yeah, wasn't it? Yes, you named it oxygen and discovered it wasn't just the D-phlogis, I can't even pronounce that. Yeah, D-phlogis-nated air. D-phlogis-nated air. The station of air. What year was this?

It was in late 18th century. It was the composition of air. What year was this? It was the 18th late 18th century that yeah It was the composition of air was discovered. It was quite remarkably close. Isn't he be think about I'm not comparing chemistry with physics here in any sense Found out useful things. Yeah Newton 1680s we have the universal law of gravitation But it's interesting that the structure of atoms molecules is a relatively recent We didn't have the technology to measure that composition and now we keep discovering more molecules that are in there You know every year goes past we discover other things the technology gets better and more sensitive So I was going to ask you that actually if you give us a breakdown because it seems like the simplest of things air

The stuff in this room. Yeah, so we know that it's nitrogen nitrogen, you know oxygen around 21% nitrogen Almost all of the rest of it apart from about 1% So most of that 1% are the noble gases and they are sorry about some of those So they have very special roles and then the ones I'm interested in, and that was for at Chemistart, are really, really tiny in concentration. So you might have one part in a trillion other molecules and they're so low in concentration because they are so reactive. So until you can make amazing spectrometers or amazing ways to weigh those gases, you

don't know that they're there. We also know there's a lot of interaction with the aerosols that Mark was mentioning earlier, and how those aerosols form, sometimes they do form from gases as well, is a really big question in science and a big question in climate science as well, because those aerosols can form clouds. It's very difficult to condense a vapor if you just have pure water. I think pure water only freezes at something like minus 42 degrees centigrade. It only freezes at zero because there are other little bits in there that you can't see. So, yeah, we are becoming more and more aware, I suppose, of the millions of things that are out there. I'm just so blown away by the fact that water doesn't freeze at zero.

Like, that feels like such a fundamental truth that everyone in this room believed. And everyone's just casually going, yeah, yeah, I knew that. Yeah. Yeah. You bunch of liars. That is mind-blowingly ridiculous.

You need, it's heterogeneous nucleation is the king, where you have another little thing. It goes for aerosols as well, and the droplets condense around something else. They don't like to stick together unless there's something bigger there to stick around. It was a beautiful thing to watch Dave's face suddenly become totally enlightened when you said heterogeneous nucleation. He just immediately went, oh of course. I'm sorry the listeners couldn't see that.

The thing I can't get past is also there's these tiny particles of air that's really, really rare, that's somewhere in the mix of other gases and things in there that we can't see, perceive, taste, touch, know anything about, but you can make a spectroscope and you can say to me, oh, there's this tiny, tiny proportion of this gas you've never heard of in here. And it's so similar to things on Channel 5 where someone's going all there's evidence a ghost is being Literally there's nothing in my education to tell me the difference between these two things other than my faith in your certificates

They just say I've seen a ghost right whereas I can show you some data you believe it. Oh, yeah Do you know what the number of times someone's come on this show and said I can show you some data you believe it. Oh, yeah Do you know what the number of times someone's come on this show and said I can show you some data And then we get back to the green room. Oh, I brought the wrong case But the the early Investigations of gases are ghost stories So we all had them if you go back to ancient times the m the mists that come out, the will-o'-the-wisps in the marshes, these are all ghosts and they were given names, will-o'-the-wisp, these kind of fairy lights. In every culture in the world, there's a word for will-o'-the-wisp, which is these little

lights that appear in marshlands, and we still don't quite understand. We know that the fuel for them is methane coming out of these marshy worlds where there's no oxygen, so you get bacterial anaerobic digestion as it calls so you get this kind of Digestion of the vegetable matter into methane and it bubbles up and it's of course flammable That's what heats our water in our homes for many of us and gives us central heating But it sometimes lights and these gas phenomena people didn't understand. It's like madness. So what do they call? They call them fairies They call them ghosts and and doors suddenly shutting because we didn't understand it's like madness so what do they call they call them fairies they call them ghosts and and doors suddenly shutting because we didn't

understand about pressure in houses and so this was further evidence of ghosts so in fact we were studying gas phenomena way back we had lots of names for them and they're called spirits and if you want evidence Dave you can light your fart and it will go blue. Oh I must have eaten a ghost I can't believe that. But that is I mean Dave that is an interesting thing, isn't it? Because that difference where we will often see kind of, you know, hucksters and grifters using what appears to be data. Yes.

And as you said, you know, you can see ghost hunters and they'll kind of go, oh, look, the dial's just gone to very ghostly. You know, but what you're doing, Lucy, you know, that bit of the difference in terms of to help everyone understand the difference when you go this measurement, how do we know this measurement works? How do we know this is evidence? For instance, you were saying about we're still finding new things in the atmosphere. Yeah. Can you just run us through how we are doing that? I mean, there's multiple different ways of measuring multiple different things and so it's horses for courses to a certain extent.

So mass spectrometry is a brilliant tool because each and every single element or molecule will have its own very specific mass, sometimes down to multiple decimal places. And modern mass spectrometers have got really high resolution. So you can measure something maybe to six decimal places in terms of its mass.

So it can only be that particular element or molecule. If it's a very complex mixture, so in the atmosphere where it's all very complicated and sometimes you want to separate things out before you even inject them into your mass spectrometer, so you can do that with chromatography, a very, very old technique which essentially slows down the path of molecules as they pass down a column. So you can inject things one thing at a time. That makes it simpler. But we're basically measuring the mass of something and that's a fairly fundamental concept, I think, that most people would believe if

they see it. So you'll see patterns in that data that make it very believable. I do believe you. I do. I just know also I can tell now that the real scientists call it a spectrometer and the ghost hunters call it a spectrometer. Ha ha ha. So if we go back historically, so the gas is like you said, the gas is like argon, for example.

Presumably this is before mass spectrometers, modern instruments. So how were things like nitrogen, argon, for example. Presumably this is before mass spectrometers, modern instruments. So how were things like nitrogen, argon, the things that don't react, how were they discovered historically? So they were weighed. You wouldn't believe this, but they were weighed. So it is still a mass.

So it's a mass thing, but they're weighing flasks of gas. And of course, a flask of gas is mostly the mass of the flask. So really precise measurements, and of course they were wildly off. And in fact, discovery of argon in the air, which is 1%, so it's much more than carbon dioxide. It's more than lots of gases,

but it was completely invisible, unreactive, so no one knew it was there. So this is a guy called Lord Raleigh, who starts to measure air, and he starts to work out what's in there. He knows there's nitrogen in there, he knows there's oxygen in there, but he finds a mass imbalance. There's something else in there, but no one knows what it is. How do you do it? What is that experiment? So you have a known volume of air at some pressure?

Well that's the thing. So you have to control all the variables, you have to control temperature because that changes the amount of the pressure. You have to, there's buoyancy. So although we don't think of ourselves as buoyant in a sea of air, in the way that you're buoyant in the sea of liquid, we are. We do have buoyancy. And you have to adjust for the buoyancy of the flask, which is sealed, because that resists the gravitational force of the gas in the air.

And the idea, of course, that gas itself has a weight and it's bearing down on all of us is another sort of thing you have to get your head around it isn't just that individual each atom has a mass you can think of the whole volume of the of the atmosphere bearing down on us and it has significant forces on us which drive all sorts of phenomena which we rely on in fact in our modern day lives so it's a lot isn't it do you have have that number in your head? It's a huge pressure isn't it? What's the weight of air on our head? One atmosphere. It's several tonnes.

But some of the early air pollution measurements were done by acid titration. So real classic sort of stuff that you, anyone's done a chemistry degree or even in chemistry A level where you've done titrations. So when you could start to measure things like SO2 and ozone and those gases that were responsible for, you know, the 1952 London smogs, for example,

you can measure the gases, then you can see the thousands of people that are going into hospital because of the smogs that were happening. Then you can put those two things together and it becomes causation, not just what's going on. We can see this vapor but now we know what it's made up of as well. So the measurement science was really crucial to showing the impacts of the atmosphere. Because I find it quite amazing, I mean there might be some people in the

audience who are old enough to have been in London when there was smog, because we're into the 1950s. There are, it's Radio 4. Yeah, don't alienate them. There's some people in here who came in for a quote unquote in 1977 and never left. But no, I'm fascinated in, yeah, so I remember the first time of seeing about that, and the density of it, and the fact that this was, you know, a regular occurrence, and it said, so what was smog, and how did they end up dealing with that? Yeah, it was so too. So sulfur sulfur being burnt from coal So the sulfur gets burnt oxidized to sulfur dioxide and that produces sulfuric acid and then this magic where aerosols get made from In this homogeneous nucleation this time

forming cloud droplets. So it becomes basically an acid, acrid, horrible smog to breathe. And over a couple of days, I think the estimates are something like 10,000 people died over over two days. It's remarkable, as you say, it's not long ago, it's in living memory that we were discovering that this is a bad idea to fill the atmosphere with sulfur dioxide. What are the big questions now? Because it might naively say, well surely we know how the atmosphere works now. What a naive question. Well I mean in terms of the big questions, we do know an awful lot. I think it's a lot now about feedbacks. So

if you have more greenhouse gases for sure the climate is going to warm. But what exactly, what feedbacks is that going to trigger? So exactly when will permafrost release methane? Why is the Arctic melting more quickly than even our worst projections? Sorry to be not very optimistic, but you know there are those sorts of feedbacks between the ocean and ice and the atmosphere that we're trying to understand to understand where we go in the next hundred years and will we meet these targets of one and a half degrees centigrade? Probably not but that's what we're trying to find out. I think it must be harder for developed nations to try and improve the air. When you were talking about the smog in

London and people talk about a real P-Super, it was visible and you could see the grime and the dirt on the buildings and you still see old buildings around this town where you can see that kind of visible evidence of the scarring that it caused. But now we sort of clean that stuff up, we're left with just the poisonous invisible stuff and that's got to be harder to motivate the public to care about because they can't see it and they can't see their children breathing it and it sort of doesn't have that immediate impact. Well it's true, I mean the problems keep evolving.

So the problems used to be coal-foured power stations in cities, luckily we got rid of that. Then it became diesel and petrol powered vehicles industry as a whole and actually you know now we predict that we're all hopefully moving to electric cars in name of year. At some point. And now a big source of organic compounds in air are personal care products. So they've really overtaken the VOC emissions from cars.

So it's using deodorants, you know, chemicals as a whole. We're just much more reliant on chemicals. Maybe our standards of hygiene Have improved as well, but it's it's an issue some people are nose-blind to it. That's my theory Well, because they just absolutely stink don't they of something and you're like Whoa, and they walk past you and and then you walk where they've just come from and you can smell it for like a long Time you think but do you not feel like this is just overwhelming and obviously they don't. They've got consent for the environment. We should celebrate that. But there is this thing about our sense of smell is the thing we rely on

for gases right? If we can't smell it it's not just seeing is it smelling and if we can't see it and we can't smell it then it doesn't exist until someone over you know puts more deodorant on near you and you just can't cope and and we have got this part of our brain which co-locates senses of smell with locations. And that's why it's such a powerful trip for memory because the olfactory nerves go straight into the brain. And so what happens is you smell something

and immediately it triggers a cascade of memories. And so we have this kind of industry selling us smells that are going to make us feel good, right? And they are now causing pollution, it's incredible. But it's a whole industry to make us feel better, because it taps straight into nostalgia or our sense of feeling about ourselves. And it's an extraordinary industry really, that is, it's a billion dollar industry selling us lovely smells. And if you go back in time back to the ancients a

perfume with something only a king or queen would have like it was so unusual to smell good everyone else in history just stank terribly so we forget this that we know not only not only we do not see smogs anymore but our biggest problem is people over perfuming themselves not what about that's very interesting because I'm sure quite a few people this audience will have read the novel perfume Yeah, which has that fascinating thing, which is the lead character actually emits no smell whatsoever So he has to create but because even though people can't detect what they detect is something's not quite right So is that part of as well when we're approaching people, this idea that

you do need to have some kind of, the smell of humanness will be detected even if it is in the subconscious? And there's the pheromone issue. So there's these invisible smells which we can't actually consciously smell. You can't sniff and go, that's rose. But a lot of the animal kingdom operates off these invisible smells that give them cues like mate with that person or that ant actually sorry not person, that bee. This is a separate show, we'll go out at 11pm. And there's a lot of debate, there's all these t-shirt experiments that go on where they get men to wear t-shirts and then they'll give them to people of the opposite sex or different sexes

and they'll get them to sniff them and see whether they're attractive or not and they use this as evidence that there are some invisible smells you give off that permeate you that make you attractive to other people and this is what of course what the whole perfume industry thrives off the idea that if you wear a perfume that you can you become instantly more attractive like the person on the telly which is then imprinted in your brain so the attractiveness to each other is also part of this mixture which is so alluring it's an elixir. We all know that there are problems with putting gases into the atmosphere as you said greenhouse gases

and so on but historically there was a problem taking gases out of the atmosphere I'm thinking of ozone. We were disarray when we with our CFCs emissions. We were talking stratospheric ozone. One of my favourite subjects. Yeah. Well, yeah, exactly. It's an interesting episode to reflect on, isn't it? Because that was a successful international collaboration. Definitely. Very quickly. Yes.

And our hairspray, and our love of hairspray, apparently in the 60s and 70s, that was one of the main. So yeah, we released chemicals into the atmosphere that destroyed ozone in huge, hugely large quantities. So the amazing thing was, is when the evidence finally came, I think it was 1985, that there was an ozone hole, and only two years later the Montreal Protocol was signed, which was absolutely incredible, which started the phase down of all of those compounds, CFCs and their replacement gases. And now every single nation, even North North Korea has signed up to the Montreal Protocol

Which is phenomenal. It's astonishing isn't it if you think about the problems we have with greenhouse gases I mean two years from the discovery of a problem Yeah, and the scientists saying there is a problem here to a treaty I mean there was pressure before then so the public I think because they the public were very concerned about that issue I mean you might remember even Margaret Thatcher raised this as an issue with Reagan so you know there was awareness of it and the public I think were willing to give up their use of hairspray for the sake of maybe not having skin cancer and of course these were specific industries that created these products and so they were they were kept on board because as long as they could have a replacement

compound so they were allowed to replace the CFCs with a bunch of compounds called HCFCs which aren't quite as harmful to stratospheric ozone but still are harmful to stratospheric ozone and on it went and more and more stringent phase downs happen but you're right it was incredible and it gives us hope I think that for the future that we are capable of making these huge leaps and gains when we come together and look at the science and talk to the policymakers. And I think that we're only just starting to understand just how much complex they are at the different levels in the atmosphere. So different levels of the atmosphere have very different effects

even for something people might think that they kind of global warming is kind of an easy thing to understand because it's just like you put something like CO2 into the atmosphere and it warms because it's a greenhouse effect. But actually it does actually depend where it is. And I think that those kind of more sophisticated understanding of kind of what happens at the first hundred meters, what happens at a kilometer, what happens at the... These are all starting to at a kilometre, what happens at the... these are all starting to be these science questions of our age, aren't they? Can we talk briefly, because as usual on Monkey Cage we've got through the first three questions

of about 20. Nitrous oxide! Sorry, I'm going to get in there because... right, Mark, nitrous oxide, that is one of the first, as far as I know, gases that got used in medical procedures. It's laughing gas. When it was first discovered it was thought to be poisonous because it does sort of make you go a bit mad. And Humphry Davy, a young scientist, comes along and he's tasked with seeing if different gases will solve different types of disease like tuberculosis. And he just starts just administering laughing gas to its patients and it doesn't really help the tuberculosis

then he starts administering to himself and he starts to giggle and he starts thinking wow why does it make me laugh why is it so funny and he can't resist really being a scientist about it and kind of self administering and it's to quite dangerous levels he invites all his friends he invites all these poets they all start taking these drugs and everyone's having a giggle and they write some bad poetry, some very good poetry, like Coleridge in fact is there at these parties. And then Davy realizes something really important, it not just makes you laugh, it doesn't just, it actually has an anesthetic effect on you.

And anesthesia as used in, was almost unheard of. People, in fact, the doctors of the day would often give people quite strong drugs, like opium or alcohol. They're not anesthetics, so basically, and they're quite dangerous, because you give them the patient too much, they're sick, or they start babbling

and moving about and thrashing about. But this is a gas that calms people down and can actually numb pain. And this brilliant discovery and all the doctors said no, no you don't want to be using that because pain is really important in healing. You need to feel the pain. And it's a long story short as lots of other ones are then vapors of ether are then explored and of course the dentists are going, we need an anesthetic because people constantly in so much pain with tooth decay.

And if we could just anesthetize them, we could pull out their teeth. And so the first dentist who uses laughing gas on a patient in front of all the medical establishment goes, look, this works. Administers the laughing gas and says, open wide to the patient. And the patient goes, oh. And they all go, oh, that means it's not really anesthetic so it doesn't really

work and so they then ridicule him again so it takes many many sort of goes at this before the medical establishment finally admit that laughing gas is a great thing to use and so there's an enormous kind of interest in these vapors and gases that that causes anesthetic effect and it's actually the Queen Victoria who it's not it's not laughing gas in that case, it's chloroform. But yeah, and we're all beneficiaries today. If you go to hospital today and you get an anesthetic, it all started with laughing gas. There are hospital trusts who are now withdrawing nitrous oxide

because of its effect on greenhouse gases. It is a bad green, I mean it's laughing gas but it's no joke yeah it does have some bad side effects as well but what they don't tell you about laughing gas so I mean I very much enjoy laughing gas during the birth of my second child maybe other women did out here as well it makes you sick as well a little bit or it can do which I mean talk about that it's toxic and and yeah you've got you've got to be careful with yeah like all of these things they have an effect on the boys are very powerful I love the fact that Queen Victoria it

wasn't laughing gas it was chloroform it was so committed to not being amused and can you talk about the technology of removing gases because that played a huge role I mean in physics in. Yeah so one way to study gases was to kind of just grab them and kind of put them in these bags and and then bubble them through liquids and study them and burn them and react them and so on and then at some point in fact in the UK a guy called Dewa starts to realize that if you can cool gases down, they will start turning to liquids. So if you cool the air down, you start to get all its constituents coming out.

And so then you realize that you can get liquid oxygen. And liquid oxygen is very useful, because then you can store liquid oxygen. You can start giving it to people in hospitals. But also, you have a way in which you can have experiments that happen at particular temperatures, very cool temperatures. And you can get even down to liquid helium, and if you get down to

liquid helium then you're down to very close to zero Kelvin, and that allows you to explore the whole quantum world, and in fact loads and loads of physics would never have been discovered without those cryogenic processes. They're also being used by people, but you have liquid nitrogen, so nitrogen is one of the first gases to come out, and that is a very useful workhorse of the scientific establishment. And it's so cheap, it's cheaper than milk because there's so much nitrogen in the air, so when you cool air down you get nitrogen as a by-product when you're trying to get liquid oxygen. And we really benefited in this country, as did lots of countries, from having an oxygen kind of producing

industrial complex because every day of the year there are big tankers of oxygen being shipped around this country to all hospitals and if it wasn't for those when they start running out people die so it's incredible actually the hospitals and this technique for making these different gases but it's also of course important to discovery of the noble gases helium, xenon, krypton, they would have never been isolated without these techniques. So it's just an incredible set of things and cooling gases down and making liquids and cryogenics is just a huge area. Can I go back to N2O though because it's also in squirty cream and I know you love squirty cream.

Yes. Mark, but let's not overlook that role. Yes. It's an important one. But the main source of nitrous oxide to the atmosphere is from fertilizer use. So it comes from soils. Okay. And so you know that's a big problem because how we need fertilizer, we need to create food and actually N2O has been going up massively in the atmosphere. It's the single, the one molecule that's the single most damaging molecule for the ozone layer. So it's actually doing more damage than CFCs right now, as

well as being a greenhouse gas. So the question is, do we all want to give up squirty cream, which is squirted out via N2O because it's one of the few gases that doesn't make it go rancid? It's a fantastic way to have a brilliant quick dessert if you're a parent, get any fruit and just squirt a bit of cream on and everyone thinks you're a hero. Why can't you just put argon in it or something? It's expensive. Well, yeah, I mean, I guess that's the question, isn't it? It's soluble in fat, N2O. But argon might be as well, but I assume it's...

We don't have much argon, maybe let's not use it in our squirting cream. Maybe the other high-level physics experiments to do with argon, maybe let's not use it in our squirty cream. Maybe the other, like, high load physics experiments to do with our controlling. We need a new gas for squirty cream, everyone. Go. I thought it was... Sorry, do it. Margaret Thatcher, she was a chemist at university. I think her PhD was about the density that could take gas in those kind of solids, so she effectively invented the Mr Whippy ice cream.

Yeah. of solids so she effectively invented the Mr Whippy ice cream. Yeah I love the image though the fact that squirty cream is also very often used for custard pie fights and the idea that that is ultimately you know it won't end with a bang or a whimper it will end for human beings with a custard pie fight somehow fits into the absurdity of what we are. Well we've managed to run out of time after five questions. You told me time is a fiction. Um... LAUGHTER

Dave, I just want to ask you, actually, because before we started this show, you were very... In the dressing room, you said, there's no way my favourite state of matter is liquid, then solid, I can't stand gas, it's my least favourite state of matter. And I just wondered, have you changed your opinion on that at all?

No I'm enjoying a rum and coke with some ice in it I guess I'm smelling something but it's definitely the liquid and the solid in the drinks though without without gases No fizzy drinks at all without gases, no fizzy drinks at all, none. No champagne. Yeah, no, fair enough, there you go, I'm sold, gas. I love that. Very nice.

Well, it would also evaporate, wouldn't it, without the gases, because they'd be evaporating. It wouldn't smell. We couldn't survive, life wouldn't survive. I mean, we'd be Mars. The drink would boil away. Yeah. In fact, there you go, rum and coke with ice in it.

I've got gas liquid solid, it's the perfect metaphor for everything you've ever talked about on this show. And the metaphor gets better with every glass, doesn't it? perfect metaphor for everything you've ever talked about on this show. And the metaphor gets better with every glass, doesn't it? Right. What do we ask the audience? We ask the audience if you could transform anything in the world into a guess. What would it be and why? What have you got, Brian?

News readers. So that they replace the gloom with a breath of fresh air. Jackie. I've got one here, but I'm just going to say I've learned a lot tonight. I've learned that water doesn't freeze at zero degrees, that Krypton is not made up and part of science fiction, and that squirty cream can go on fruit. I'm learning. I'm always learning.

But on your thing, from Penny Simpson, she would make smarties into gas so that she can fit more in her mouth, so long as the gas still tasted of smarties. It's not scientifically accurate that you'd fit less in your mouth, wouldn't you, if you filled your mouth with gas? You've become a cropper there, Penny. You've had an absolute man. Thanks for joining in. wouldn't you? You filled your mouth with gas. You've become a cropper there, Penny. You've had an absolute man. Thanks for joining in.

Because we're talking about the number of molecules of Smartie. I do know someone who's developed this technology already, which is basically breathable, as they call it, breathable flavours that you can have. So you can have a breathable coffee or a breathable chocolate bar without the calories. And so there are products on the market that are doing that, yeah. I'll just say that that was also the perfect physicist moment. Penny came up with an idea filled with joy and he destroyed Macbeth because he proclaimed methane That's only in the folio edition of course the methane line. What have you got there, Brian? From Andy, this is good.

Rationality, because there's a world shortage of that. From Graham Bodkin, I would put all politicians into group 18 of the periodic table. It would be the noble thing to do. Yeah, Kirsty says, my holiday luggage to avoid random and ridiculous charges from budget airlines. luggage to avoid random and ridiculous charges from budget airlines. LAUGHTER Martin says it would transform Donald Trump into Argonne so as to make him inert.

LAUGHTER Thanks to our panel, Lucy Carpenter, Mark Madovnik and Dave Gorman. APPLAUSE Next week, next week, we're going to be heading to the Royal Society for a very unexpected take on the history of science. Why is it unexpected? Because they don't know we're coming. LAUGHTER Thanks. Bye-bye.

APPLAUSE In the infinite monkey cage That's a travel In the infinite monkey cage Turned out nice again. She needs to see this. She needs to see Paddington too apparently, so keep it brief. Nobody, comma, in the country, comma, can access any of their money.

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