- And... rolling.
I can't clickbait this video.
I mean, I could, but it wouldn't really be fair to anyone involved.
I know the title and the thumbnail aren't going to pull loads of people in,
but I hope that you can trust me
when I say: I promise this story is really interesting.
Because it is.
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 line in 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 realised
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 realise
you could cook efficiently with the wavelengths
that were put out by radar, and then realised
that you could sell that, and then realised,
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 past a 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, defence contractor Raytheon,
they release the first commercial microwave.
It was called the Radarange.
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.
[microwave dings]
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...?
[keyboard clicks]
- "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, at 101 years old
lives somewhere vaguely round here on the south coast of England,
goes for a walk along the coast every day,
and was happy to be interviewed.
- One biologist, Audrey Smith,
was able to revive a hamster that had been frozen.
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 don't you use diathermy?"
For 10 shillings of my own money I 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.
And I said, "Look, here's your diathermy."
I thought this is very untidy, made some inquiries
and sure enough, there were 10-centimetre magnetrons
that had been invented by Boot and Randall at Birmingham University during the war.
To get hold of one of those is not easy.
And this is where being in a government department helped a bit.
So I just made a few inquiries.
"How do I get hold...?"
And they said, "Oh, well, they're working on them down at... just above Portsmouth."
I said, "Any chance of borrowing one of your magnetrons?"
And he said, "Oh no."
He said, "We can give you one if you want. It's an interesting cause, why not?"
I've joined this up with a 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 put a potato in it and baked it. And it was perfectly all right.
- The safety procedures were occasionally a 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 wavelength as 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 put 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 a 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 of survival 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 respiration to start pumping oxygen around the body
almost every rodent they froze was 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 immense importance to medicine.
So for preserving tissues for transfer and also for blood transfusions
because at the moment blood was kept at the blood bank
for three weeks and then thrown down the sink.
- Imagine if that had worked on bigger animals.
Back then humanity did not know what the limits were.
This was an open question.
The reason that all those 1960s science fiction writers and comic book authors
had people being frozen in time or astronauts being sent off in cryosleep
might be because, for a little while,
it looked like that might actually be possible.
If freezing and diathermic reheating worked on hamsters...
then maybe it would work on rabbits.
If it worked on rabbits, then maybe 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 you can get the anti-freeze agent
to diffuse into the cells.
A human's too big.
It's just a matter of size. A hamster is an acceptable size.
- Sometimes research hits a brick wall.
Find out a neat thing about hamsters, check.
Casually invent a microwave and then don't commercialise it. Check.
Find a way to safely send astronauts to other planets?
Not this time, unfortunately, but the researchers tried
and that feels like a story that shouldn't be buried
as a vague anecdote in a newspaper from years ago.
- I think in an awful lot of science
where there's a success it's not a scientific thing.
It's an invention, which is something quite different.
And I think personally I'm much more of an inventor than a scientist.
- My thanks to James Lovelock for his time.
His latest book "Novacene" is part memoir and part look to the future
and there's a link to it in the description.
- Oh, that was a mistake.
That was... I...
Oh that's going to be a nightmare to wash.
All right, well, I guess I don't get a second take, 'cos...
I put that on low!