This is one of the best things I've found while researching in years. So this starts when I'm looking up old television shows and I'm about three research tangents deep, and I find this incredible linen a newspaper article from 1997: "The microwave was invented to meet a need "to heat hamsters humanely in 1950s laboratories." And I read that and I thought: that's ridiculous. No, it wasn't. Was it? There's a well-known story about the engineer who "invented the microwave".
Percy Spencer, just after World War II, was working on one of the new military-grade radars while it was active, and he realized that the peanut bar in his back pocket had melted. Which implies that the radar also nearly cooked part of him as well? Unshielded radars are really dangerous, but it was the 1940s. The attitude to safety was a bit more lax. Now it wasn't a surprise that electromagnetic radiation could heat stuff. That had been known for a while. People had actually been using it for medical therapies for a while.
Different wavelengths had different effects, but Percy Spencer was the first person to realize you could cook efficiently with the wavelengths that were put out by radar, and then realized that you could sell that, and then realized, well, I could turn that into a usable product. Because a massive radar dish is basically the same technology as this microwave. I'm not going to try and take this thing apart. I'm not qualified. And there is a high-voltage capacitor in here which can carry enough charge to kill. Don't mess about with these unless you know what you're doing. But inside here is... Inside here in the bit you can't access, there's a microwave generator called a magnetron. It moves electric current pasta big magnet with a hole in it.
And because... physics, that produces electromagnetic radiation. Tune the size of the hole in the magnet, you get different frequencies of radiation. The best analogy I've found is that it's like blowing air over glass bottles and changing the pitch by changing the amount of water inside. So...[glass whistling at different tones]. That, but with electricity. ...look, I don't have a physics degree. Long story short, a magnetron converts electricity into electromagnetic radiation. You send pulses of that radiation out into the sky and you listen for the echoes, you've got radar and you've helped win World War II. Or you could put a magnetron inside a safe radiation-proof box called a Faraday cage, you tune the wavelengths so that water absorbs the radiation easily, and you've got a microwave. And you can cook lunch.
The technical term is "diathermic heating". In less than a year after the melting peanut bar incident, which could so easily have been, like, the "cooked hand incident" or worse, but less than a year after that that engineer's company, defense contractor Raytheon, they release the first commercial microwave. It was called the Rearrange. It was the size of a fridge. It had to be actively cooled. It was incredibly expensive and it was designed for big commercial kitchens. That was 1947. The first microwave as we'd know it today, a cheap box that you plug in, that was from the late 1960s once magnetron technology had moved on a bit.
At no point in that well-referenced, well-known story does anyone mention heating hamsters in laboratories in the 1950s. So that should be pretty easy to disprove, right? It's going to be an urban legend. There are a lot of urban legends like that. So I started doing some journal searches and pretty quickly I found papers from the 1950s talking about the reanimation of frozen rats and hamsters. Those papers were written by scientists at the National Institute for Medical Research, a government laboratory in Mill Hill, in suburban North London, about half a mile that way. I would have filmed closer to that, but unfortunately, it was pulled down a few years ago and the whole area is now a load of new-build housing. Anyway, National Institute For Medical Research.
In the 1950s, that research included cryobiology, the effects of extreme cold on bodies and tissue. Scientists at that lab froze rats and hamsters beyond the point of death. They used ice and a bath of propylene glycol, which is airplane de-icer, held at below zero, and at that point, the animal is dead and will not recover on its own. No heart rate, no breathing, core temperature around 1°C, somewhere between 10 and 50%of the animal's body water frozen to ice. And then by applying hot spatulas to the chest or high-intensity hot beams of light the researchers would try to warm the animals up and bring them back to life.
The success rate wasn't great and the animals were often left with burns, but it did sometimes work. We'll get to why they were doing that later! But by 1955, one of the researchers has the idea to use a magnetron, reasoning that it'd be a lot more safe and humane to reheat the whole animal at once rather than risk burning it. Actually, I say one of the researchers, there's a name on that paper that might be a bit familiar. James Lovelock, one of the last independent scientists, born in 1919, back when "scientist "could be an entire job description rather than "botanist" or "physicist "or "computational linguist". Someone who worked across disciplines on whatever they found interesting or whatever they were hired to do. Lovelock is best known for inventing Gaia theory, the idea of earth as a self-regulating system.
He also invented the electronic capture detector which found CFCs in the atmosphere and helped discover the ozone hole. Hardware that he helped design for NASA is sitting on Mars because it landed there with the Viking probes in 1976. And one of the early projects in his career, back in the 1950s was at the National Institute for Medical Research freezing rats and hamsters, and he had the idea to use microwave di-a-ther-my..., dia-tha-my? dia-tha...? "Diathermy." - To reheat them. But the papers and anecdotes from back then all seem to contradict each other. The timeline is difficult to piece together. There are reliable sources with completely different stories and claims.
So I went to ask him about it. - "Do you know you're the first person to come "and ask me about the freezing work?" - Because James Lovelock, 101, lives somewhere along the south coast of England, he travels along the coast every day and enjoys being interviewed. - Another biologist, Audrey Smith, was able to resuscitate a winter hamster. When they woke up, they got a gigantic burn all across their chest and that must have been pretty painful, and it was messy. I thought, this is a lousy way to do it. So I said, "Why do not you use diathermy?" For 10 shillings of my own money bought a surplus RAF transmitter, joined it up, and sure enough, it poured out 30 watts at 30 megahertz, Which is just about right. And I took it into the lab the next day.
I have joined this up with waveguide, into a metal box. It wasn't so much a box. It was just a thing made out of chicken wire, except it's finer than chicken wire, a bit closer to mesh. And that was just like the box of a microwave oven. And I fed the microwaves into it. And I told Audrey, now, put your hamster in there! - That's a microwave. James Lovelock may not have invented THE first microwave but he certainly invented A microwave. The idea of using magnetrons to heat stuff wasn't his, but no one else was putting one in a Faraday cage box on a desktop. Big commercial microwaves for restaurant kitchens aren't the same thing, and besides, they weren't even on sale in the UK until a few years later. - I keep a potato in it and baked it.
And it was perfectly all right. - The safety procedures were occasionally bit lax by modern standards. - In the course of the experiments while we were building it the thing was running open and the radiation was bouncing all round the room and the light bulbs would light up without warning. The filament just had the same wavelengths the radiation, and it would absorb it and light up. And pound notes were the funniest one. They'd catch fire because the metal strip inside was just about the wavelength of the magnetron. - And here's the really amazing thing, it worked. - We keep the hamster in there, frozen solid. And I mean frozen solid. It was like a bit of wood when you dropped it on the bench.
Turned the thing up to full power on the microwave, which was about kilowatt coming out of it. And with a timer. And after so many seconds, the hamster woke up, started wandering around. - Do I need to say, don't try this at home? I mean there are enough people of all ages watching that statistically yes ,I do need to say it. Don't try this at home. It's unnecessary cruelty. You won't be doing medical research, you'll be doing a crime. Context is really important, but also the research has been done! More than 50 years ago.There are charts ofsurvival rate and heating, and it turns out that with a microwave, because that's what this was,with a precise calibrated microwave and with artificial respirationto start pumping oxygen around the body almost every rodent they frozewas successfully reanimated.
That's the word that the biologists use. Reanimation. Healthy, behaving as usual and given a retirement at an animal home,according to one of the papers. Back from being frozen to death,sometimes multiple times. So the last question is: why? - Well, this could be of immenseimportance to medicine. So for preserving tissues for transferand also for blood transfusions because at the moment bloodwas kept at the blood bank for three weeks and thenthrown down the sink. - Imagine if that had workedon bigger animals. Back then humanity did notknow what the limits were.
This was an open question. The reason that all those 1960s science fiction writersand comic book authors had people being frozen in time orastronauts being sent off in cryosleep might be because, for a little while, it looked like that mightactually be possible. If freezing and diathermic reheatingworked on hamsters... then maybe it would work on rabbits. If it worked on rabbits, thenmaybe it'd work on primates. And if it worked on primates...then maybe it'd work on humans. It didn't, unfortunately.It doesn't scale up. - You cannot freeze a human. It's partly a matter of how quickly youcan get the anti-freeze agent to diffuse into the cells.
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