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June 10, 2024 39 mins

Who invented the MRI? Well, that's actually tricky to say, and it is a topic that still opens debate. In this first part, we'll talk about the various developments in physics that led to the idea of an MRI machine even existing.


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Episode Transcript

Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Speaker 1 (00:01):
Welcome to Stuff You Missed in History Class, a production
of iHeartRadio. Hello, and welcome to the podcast. I'm Holly
Frye and I'm Tracy B. Wilson. Hey, Tracy. I had
my first MRI recently. Yeah, do not recommend. Didn't enjoy it. However,

I do recommend. Yeah, Yeah, I have had one, but
I think I had the easier version of it than
you did. Did you go in the tube? Only my
leg had to be in the tube? Oh the jealousy
I feel. My head did not have to be in there. Yeah.
I my MRI tech Timothy, who was one of the

kindest people I have ever dealt with in medicine, was
very sweet and he let me flip so that my
head was the last thing in. But my head was
in the tube, and I'm claustrophobic, and I definitely had
some freaky outy Yeah, but it was cool to get
a ton of information about what's going on in my body. Also,
I'm fine. If anybody's worried, hell a little, we'll gall

bladder eviction. But all well. But as I was lying
there in that noisy, claustrophobic tube, I literally was like,
who on Earth decided this was a good idea. This
is a torture device. It is a good idea, you
get really great images. But it made me wonder how
this whole thing came to be. And then I started
looking at it and I discovered this is a very

controversial question of who invented the MRI, and so I thought,
let's unpack that. So let me be real. I love science,
but getting into the nitty gritty on quantum mechanics to
part of this and superconductors and similar ideas is beyond
what I can grasp. Sure, so we're going to talk

about how the science came to be. We'll talk about
some of the science, but it's definitely the layman's terms
and cliffs notes versions when it comes to any of
the hard science here. So if there are any scientists
in the crowd who are like Holly, that's not quite right.
I'm not surprised. This is also a two parter because
there were a lot of people that worked on this
technology in different ways over the years, even people that

didn't know that their work was going to become part
of it, And as much as possible, I really wanted
to highlight some of their key biographies because a lot
of these men have Nobel prizes. A lot of these
men really changed the world as we know it. So
it's two parts, and part one covers some of the
key moments that led up to the idea of an

MRI even existing and the developments in technology that got
to that point where someone was like, could we apply
this in a medical way? And then part two is
going to delve into how the first MRI machine was
built and then all of the controversies that followed. So
we'll start with what magnetic resonance imaging is at its

most basic, it's the use of a strong magnetic field
in conjunction with radio waves to get imaging. The most
common versions of MRI machines look like tubes that a
patient is slid into. This tube is surrounded by a
superconducting magnet and that in turn is surrounded by liquid helium.

The machine generates radio waves that stimulate the protons of
the hydrogen atoms in the patient's body. There are other atoms,
but we'll talk about why hydrogen is the important one
later on. Those protons spin out of equilibrium because of
the magnetic field, and then when the radio waves are
stopped and the protons hustle to realign to normal. That movement,

which we'll talk about again later, it's called relaxation, can
be captured by sensors in the machine, and this all
comes together to create detailed imagery of everything going on
in the body. Sometimes dyes are used to amplify the
imagery that's able to be captured, and then doctors and
radiologists can analyze that captured information to identify disease or

issues that might need treatment. Like nowadays, you know it's
things like is there misalignment in your knee or hip
or whatever. It can be used for a lot of
different things. So if you've ever had an MRI, if
you've talked to somebody who has had an MRI, you
know they're loud, notoriously loud, and also inconsistently, so there

are banging noises that just change throughout the imaging session.
I think that's part of what makes them seem stressful
to people, is that this unpredictable banging noise is happening.
Go in a tiny closet, someone is going to bang
against the walls of the closet with pots and pants.
It's cool, it's for medicine, just saying tight. Yeah, So

all of that banging is because the current that runs
the magnetic field is passing through three differently aligned sets
of coils. They are associated with the x, y, and
Z planes of visual image capture. This combination of electric
and mag forces is called a Lorentz force, and that
force is acting on the coils. It causes them to vibrate.

As these different pulses are used to get a complete picture,
the vibrations changed, so the different noises happen, and the
patient is sort of inside all of this most of
the time. I was lucky in that my head was
like not fully into it, so I had a little buffer.
But that means that everything is amplified in there. Yeah.

I read one thing that described it as like imagine
you're sitting in the middle of a drum while someone
is drumming, and it was like, oh, yeah, that's pretty accurate. Actually,
the huge benefit of an MRI is that it is
a non invasive way to get excellent imaging for analysis.
It doesn't emit radiation the way X rays or CT
scans do, and it can capture an awful lot of detail.

But it's also not a technology that everyone can take
advantage of even if the issues of cost, insurance, and
availability of machines were non existent. And that's because of
the magnet field and its potential to interact with non
tissue objects. So if you have had a surgical implant
like a pacemaker or an insulin pump or any number
of other devices, you shouldn't get in an MRI because

the magnet will pull on those. There are also issues
when it comes to patients with claustrophobia. Boy don't I
know it, Although there are efforts to get around this problem.
One of the ways that this has been addressed is
through the development of open MRIs that are open on
the sides and even in some cases the use of sedation.
And there are unsurprisingly a lot of people involved in

the development of this technology and a lot of debate
over who should get the credit for it. This is
an episode that moves a little closer to our current
time than our episodes usually do, because disagreements about how
to give credit continue up to today. One part of
the issue is that different people develops different ideas that

will ultimately combined to create magnetic resonance imaging. That's not
necessarily unusual, but each stage of development was also a
huge advance, So which moment should be credited most, that's
difficult to say. Another thing that makes it such a
puzzle is that some of the work was done in

the medical community and some of it was done in
the physics community. So okay, As Tracy just mentioned, there
is lots of science that builds on other science to
pave the way for this tech, but one of the
very earliest important steps specific to this was made by
physicist Isidore Isaac Rabbi. Robbie was born on July twenty ninth,

eighteen ninety eight, in Raimenov, which was part of Austria
Hungary at the time. Today it is part of Poland,
and when he was still a small baby, his parents,
David Robbie and Janetigue, moved to New York City, where
he went to public school, and after completing his early schooling,
he attended Cornell and got a bachelor's degree in chemistry.
But then when he went to graduate school at Columbia,

he changed his field of interest to physics, and he
received his PhD in that field in nineteen twenty seven.
For two years after receiving his PhD, Robbie did research
in Europe, working alongside the likes of Nils Heinrich, David Bohr,
and Werner Karl Heisenberg. Then he returned to Columbia to

teach theoretical physics. In nineteen forty he joined MIT to
work on radar and the technology behind the atomic bomb.
He would go on to work with the Atomic Energy
Commission starting in the late nineteen forties. Was credited with
coming up with the concept for a collaborative international laboratory
that eventually became CERN. But the most germane part of

his work, as it relates to the topic of MRIs,
began in the nineteen thirties when he started studying the
nuclei of atoms and how magnetic fields affected them. He
developed what he called a resonance method for recording the
magnetic properties of atomic nuclei. That meant he was able
to develop a method for detecting and measuring the rotations

of atoms and molecules. He won the Nobel Prize in
Physics for this work in nineteen forty four. Yeah, as
we talk through all of these different biographies, you'll see
how many of these people overlap with the same kind
of researchers and some of the same big names that
you have heard probably throughout your life. The next person
that we have to talk about is one of those

people who both overlaps with a lot of famous people
and is himself famous, and that's Felix Block, who was
a physicist who was born in Zurich, Switzerland, on October
twenty third, nineteen oh five. Felix had a somewhat difficult childhood.
When he started school at the age of six, he
apparently spoke with what's described as an odd accent and

other kids made fun of him. And he also lost
his older sister, who he was very close to, when
she was just twelve, and he is described as having
been withdrawn and depressed for several years after her eyeing.
The outbreak of World War One only added to his depression,
but eventually he found solace in learning, and while he

got a comprehensive education, math was absolutely always his favorite subject.
He enrolled in Zurich's Federal Institute of Technology in nineteen
twenty four with a focus on engineering, but he eventually
switched to physics, later saying that that was a decision
he just could not help making. When it came time
to move into graduate studies. Block worked under Werner Heisenberg.

He was Heisenberg's first graduate student, and together they used
quantum mechanical theory to examine metal conductivity and the relationship
between thermal conductivity and electrical conductivity. This ultimately led to
Block's thesis, The Quantum Mechanics of Electrons and Crystal Lattices
that was published in nineteen twenty eight. This work, which

involves the discovery of what are called block waves, is
often cited is as opening the door for technologies in radio, television,
space exploration, and more because it catalyzed the ability to
shift from vacuum tubes to semiconductors yep, it made everything
smaller and more compact. After touring Europe to work alongside

other researchers in physics, Block became Heisenberg's assistant in Leipzig
in nineteen thirty. He continued to publish, writing important work
on ferromagnetism and quantum theory. In nineteen thirty two, he
became a privat docent. That's a lecturer who isn't paid
directly by a school as a salaried employee, but as

someone who makes their living through the fees that students
pay for their classes. But this position allowed him to
continue his own research and his own writing as well.
But the Nazi Party was rising to power, so Block
sought away to leave Leipzig. He applied for and received
a Rockefeller Fellowship, and that allowed him to go just
about anywhere he might want to work. He had a

gap between when he left his teaching job and when
the fellowship began, and he spent that time in Zurich.
He moved on to Rome once the fellowship began, working
alongside Enrico Fermi. Then he was offered a job at Stanford,
working as an associate professor of physics. That was autumn
of nineteen thirty three, and Hitler had become Chancellor of Germany.

The twenty eight year old Block took the job and
left Europe. Coming up, we're going to talk about another
big name in science that is part of Felix Block's story,
but first we will pause for a sponsor break. So

Felix block story has already brushed up against a lot
of notable scientists of the early twentieth century, and that
continued once he moved to Stanford. For example, he spent
a lot of time with Robert Oppenheimer, who was working
at Berkeley at the time. Two of them even co
taught a seminar that crossed over between their schools, alternating

locations for each lecture. I feel like that's kind of
an unusual and unprecedented and probably difficult to do thing today.
This was a really exciting time though. In physics. The
neutron had been discovered by James Chadwick in nineteen thirty two,
and Block, Oppenheimer, and all of their colleagues in the
field were working to understand neutron interactions. Block was involved

in a lot of noteworthy moments in science history, and
specifically in regard to quantum mechanics. He worked at Los
Alamos during World War II and worked in radar evasion
tech at Harvard. When World War Two ended, Block returned
to California and he resumed his research at Stanford, specifically
focusing on nuclear magnetic resonance. This work was published as

the paper Nuclear Induction, which Block wrote with co authors W. W.
Hanson and Martin Packard in nineteen forty six. Felix Block
and his colleagues described the way that nuclei of various
elements are influenced by magnetism, but completely independently of Block's lab.
Another man, Edward M. Purcell, also published a paper in

nineteen forty six titled Resonance absorption by nuclear magnetic moments
in a solid describing the same thing. Percell, like Block,
had co authors. These were HC. Tory and RV. Pound.
They described the same discovery. This would become an important
piece of the bedrock of MRI technology. Although neither of

these men were interested in medicine, Percell, like Block, was
a physicist. The work of both labs examined the way
that nuclear magnetic resonance, known more commonly as NMR, affected
both liquid and solid matter. So let's backtrack a little
bit to contextualize who Percell was. Edward Mills Percell was

born in Taylorville, Illinois, on August thirtieth, nineteen twelve. His father,
Edward A. Percell, worked as a manager at the phone company,
and his mother, Elizabeth Mills Purcell, was a teacher before
she married and had Edward and his younger brother. Edward
is said to have just loved playing with the discarded
equipment from his father's job, and that playing with it

helped stoke his interest in technology. And science. He also
routinely read his father's copies of the Bell System Technical Journal,
which cracks me up a little bit. Edward later said
of that journal quote, they were fascinating because for the
first time I saw technical articles obviously elegantly edited and
prepared and illustrated, full of mathematics that was well beyond

my understanding. It was a glimpse into some kind of
wonderful world where electricity and mathematics and engineering and nice
diagrams all came together. The nice diagrams part of that
quote charmed me so much. It's so sweet he I mean,
seems like he was probably a great dude. Yeah. In

nineteen twenty nine, Percell enrolled at Purdue University to study
electrical engineering, but he fell in love with physics as
an undergraduate and started an independent study course on the
subject while still maintaining his status as an electrical engineering
major when his senior year ended. He stayed at the
school through the summer after graduation to work on two

papers that were eventually published, one on electron diffraction and
the other on thin films manufacture. On the heels of
his graduation, Percell was given an exchange fellowship that took
him to Germany, and this was nineteen thirty three, so
he was getting into Germany just as Block would have
been figuring out a way to leave. So this was

kind of a strange time to have this opportunity, to
be sure, but it was also life changing in an
unexpected way. On the ship across the Atlantic, ed Purcell
met a literature student from the US named Beth Busser,
and the two of them hit it off. They went
on a date in Europe to a physics lecture, even
though Beth didn't understand any of it, apparently, and they

became a couple and they married a few years later.
When that year of study in Germany concluded, Percell went
back to the United States and started a position in
the physics department at Harvard University, where he worked on
his dissertation on three dimensional focusing properties of electrons. When
his thesis was finished, Percell became a lecturer at Harvard.

Like many scientists, Percell was also involved in technology research
during World War II. To help the war effort, he
worked at the MIT Radiation Lab to improve radar. He
took a leave of absence from Harvard to do this work.
A lot of them took leaves of absence from their
established positions so that they could go to different labs
and work on this stuff. He was head of the

Advanced Developments Group at Harvard, and his team's work moved
radar forward in a way that offered greater resolution in imaging,
particularly from an aircraft, though real world function was seriously
hindered by atmospheric humidity. Purcell was asked to stay at
the MIT lab after the war ended to work with
a handful of other scientists to document their work that

they had done during the war to prepare it for publication.
And it was during that post wartime at Harvard that
he started to collaborate with Robert V. Pound and Henry C.
Torre to, according to Pound quote, jointly design and undertake,
in our spare time an effort to detect resonant absorption
of radio frequency energy by atomic nuclei in solid matter

held in a strong magnetic field. So that of course
led to the paper that dovetailed right on the one
that Felix Block had written, so back to the nineteen
forty six work in nuclear magnetic resonance. The reason this
work was so important was because if you can observe
a specific type of matter reacting to a strong stationary magnet,

and you can identify the unique way that any given
elements nuclei by hany even that situation, you can create
a sort of map to read unknown matter, apply magnetism,
watch the reaction of the nuclei, and then match that
reaction to the database of observations. You'll figure out what
you're dealing with. And while this was not aimed at

medical use initially, you can see how it would become
important in that field because it could be applied to
tissue to detect things like cancer. Block and Purcell met
for the first time in April of nineteen forty six.
They both attended the meeting of the American Physical Society
that took place that month in Cambridge, Massachusetts. They got

to talking and realized they had been working on the
same idea, although they didn't approach it in exactly the
same way. And this is one of those rare and
sort of lovely instances where the two of them recognized
each other as competitors but also became friends. In nineteen
fifty two, Block and Purcell shared the Nobel Prize for

Physics quote for their development of new mal methods for
nuclear magnetic precision measurements and discoveries in connection therewith. In
his Nobel speech, Felix Block talked about all the scientists
who had come before him and laid the groundwork for
his research. When Felix Block got the news of this
joint award, he sent Percell a telegram in verse that

read quote, I think it is swell for Ed Purcell
to share the shock with Felix Block. If that's not
the cutest thing you've ever seen, I kind of love
these two. Love their I love their friendship. Okay, So
Block and Purcell have the building blocks figured out, so
of course next there will be a Eureka moment that
leads to the MRI. Not exactly, there is a big

time gap here. We'll talk about that gap and how
the idea of magnetism to analyze matter made the jump
from physics to medicine after we hear from the sponsors
that keep the show going. Though there was this recognition

in the form of a Nobel Prize of the importance
of the work of Block and Purcell, it didn't lead
to a sudden adaptation of this information into medical use.
In a text written by al Luton titled Magnetic Resonance Imaging,
A Historical Introduction, which was written in nineteen ninety nine.
The author notes, right out of the gate quote, the
discovery and development of magnetic resonance imaging is one of

the most spectacular and successful events in the history of
medical imaging. However, there is a time gap of almost
thirty years between the discovery of nuclear magnetic resonance simultaneously
and independently by Block and by Purcell in nineteen forty
six and the first imaging experiments in the nineteen seventies
by Louderber and by Damadian. We're going to be talking

about Louderber and Domadian at length later on. In nineteen
fifty three, Eric Odeblad traveled from Sweden to the United
States research as a Rockefeller Foundation Fellow. Odoblad was born
on January thirty first, nineteen twenty two, in Christenham, Sweden,
and in nineteen fifty two, after completing medical school in Stockholm,

his career was really just beginning. He had begun to
work just the year before at the Karolinska Institute, which
is a medical university, and his Rockefeller Fellowship took him
to Stanford University where he met Felix Block. Odeblod asked
Block for the chance to use the NMR spectrometer that
Block used in his lab to look at human tissue samples.

So he had this idea, but Block turned him down
because he thought this was a machine for physicists and
not doctors. But Odeblad did not let go of this idea,
and after he returned to Sweden he managed to get
an NMR spectrometer of his own, and there he worked
with Gunner Lindstrom on research with human tissue that would
become the basis of the paper Some Preliminary Observations on

the Proton magnetic Resonance in Biologic Samples that was published
in nineteen fifty five. Odeblad and Lindstrom showed in their
paper the differences in proton signals of various types of samples.
At the very beginning of the paper, for example, they
include side by side images of the proton signals of
water and living yeast cells when the same magnetic field

and operating conditions were used on the two samples, and
its apparent even to the layman that they're producing different signals.
The next big event on the MRI timeline, and it's
a big one. Takes place in the nineteen sixties when
doctor Raymond Damadian was working with nuclear magnetic resonance spectroscopy,

but this was still not working with human tissue. He
was examining chemicals contained in test tubes after using NMR
to look for potassium in dead sea bacteria samples as
an avenue of research prompted by his colleague Freeman Cope.
According to Domanians, the county started to wonder if this
technology could be applied to scanning human bodies. When Damadian

talked about this, it's apparent that the analysis of the
dead sea bacteria stoked his imagination of what this tech
could do. Quote. I remember the first time I saw
a potassium signal. This huge blip filled the ocilloscope screen.
I had never seen an NMR machine, and it had
a profound effect on me. I mean, wow, in a

few seconds, we were taking a measurement that would usually
take me weeks sometimes months to do accurately. I had
a reaction to the potency of this. It was doing
chemistry by wireless electronics. So let's take a minute and
talk about who was this passionately curious man. He was
born Raymond Vaughan Damadian on March sixteenth, nineteen thirty six,

in Manhattan. His Armenian American family lived in Queen's and
both of his parents worked. His father, Vaughn, was a
newspaper photo engraver, and his mother, od was an accountant.
Raymond Damadian was clearly an incredibly smart kid. He loved
to build model planes, and he loved to solve problems.
He also showed both talent and dedication to violin, and

he enrolled at Juilliard, where he studied for several years
until he switched his life plan to science. He received
a Ford Foundation scholarship and studied mathematics at the University
of Wisconsin before moving on to medical studies at the
Albert Einstein College of Medicine. After completing his medical degree,
he moved on to biophysics at Harvard, and it was

there that his interest in magnetic resonance was sparked. He
next moved to a position at Downstate Medical Center in Brooklyn,
and there his research and fascination with magnetic resonance continued.
Damadian cited a couple of different inspirations for his interests
in applying this technology to living tissue. One mentioned in

his biography Gifted Mind, which he wrote along with the
co author, was that when he was ten and had
seen his grandmother, Jean Victoria, struggle through breast cancer, which
she eventually died from. He described her last months as
complete agony and suffering, and wrote of the experience quote,
my precious grandmother's death cut me deep inside, leaving a

lasting emotional scar. While not the sole reason I pursued medicine,
I believe her death was one factor that drove me
into research, fueling my passionate quest to find a cure
for cancer. Another was something that happened to him when
he was still at Harvard. He started having really bad
pain in his abdomen and went to a doctor. X

rays revealed nothing, but he was still experiencing pain, and
it frustrated him that he could get treatment based on
like a best guess at what might be the problem,
but could not get a definitive answer. The only option
was an exploratory surgery, and that seemed like an extreme
step when the cause of an illness could be relatively minor,

like there just had to be some better way to
get information about what was happening inside of a patient's body.
When Domanian had his idea about applying magnetic resonance to tissues,
he first started experimenting with rats and using pulse radio waves.
He was able to see that rats that had cancerous
tissue bounced back different radio signals than rats without cancerous tissue.

He had identified values that are today known as T
one and T two and how they could be used
to identify cancer. So for a very abbreviated and simplified
lay person's version of what those values are, they are
measures of internal molecular motion. Each of them is a
time constant, thus the use of the letter T and

each of them references what's called relaxation. In this case,
relaxation means the process of returning to natural equilibrium. When
magnetic force is applied to a molecule, the nucleus spins,
and when the magnetic four versus removed, the nucleus returns
to its original state. That's a really rough way to
describe relaxation in this context. T one, which is also

called spin lattice, references the return to longitudinal magnetization. The
z axis, T two, which is called spin spin is
the disappearance of transverse magnetization on the x y plane.
And if you ask me to elaborate further, I would
get a sad look on my face because I can't.
That's my limited grasp. Those words went from my eyes

directly to my mouth with no comprehensive Yeah, it's hard
to wrap my brain around it. But here's the important part.
Not all nuclei spin when they're exposed to magnetic resonance.
Only atoms with an odd number of neutrons or protons
do so. Something like carbon twelve, which is a carbon

isotope with six protons and six neutrons, will not spin
because it's very very stable. This is why we mentioned
at the very beginning of the episode when talking about
the basics of MRI that it is typically hydrogen that's
the focus. It has one proton, and it's one of
the most common elements of the body. There are other
elements that can be used in MRI imaging, but hydrogen

is the most common. The meadian believed that if he
could show that magnetic resonance could identify cancer, it would
be proof of concept to develop a machine to perform
that function that could be used by doctors. He used
his work with rats as the basis of a paper
titled Tumor Detection by Nuclear Magnetic Resonance that was published

in Science in nineteen seventy one. The paper explained how
the measurements of T one and T two were taken
on six different normal tissues in rats muscle, kidney, stomach, intestine, brain,
and liver, and also in two different kinds of malignant tumors,
one a novikov hepatoma and the other a walker sarcoma.

The paper noted that quote relaxation times for the two
malignant tumors were distinctly outside the range of values for
the normal tissues studied, an indication that the malignant tissues
were characterized by an increase in the motional freedom of
tissue water molecules. The following year, on March seventeenth, nineteen
seventy two, Damadian filed a patent for an apparatus and

method for detecting cancer in tissue. That patent was granted
on February fifth, nineteen seventy four, with the number three million,
seven hundred eighty nine eight hundred thirty two. It was
the first of many, many dozens of patents he would
file over the next several decades with Domadian on the
precipice of taking the leap into actually building a machine

that could apply nuclear magnetic resonance to a human body
as a diagnostic tool. We will end part one. Part
two will cover Damadian's challenges and work to realize his vision,
as well as the events that led to a lot
of controversy and bad feeling about this technology. Now I

have relatively relaxed listener mail after all of that science
which breaks my brain, and I wish I understood it better.
This is actually I have two pieces that are both
in regard to our barbed Wire episode and are about pronunciation,
but so kind. The first comes from our listener Elaine,
who writes, Hi, I live in the Chicago area or

Chicago Land as we call it, writing in a totally
friendly and non critical way to let you know the
crazy way locals pronounce to Calb they say the L sound.
We say it to Cab because we both lived in
Georgia up yep into Cab County, specifically, Yeah, to Cab County, voter,
to Cab County, jury duty, all that right, Cab Avenue. Uh,

and we don't pronounce the L, and she writes, they
say the L sound. I don't know how to spell
that out phonetically, but it's basically pronounced by saying all
the letter want to know how we say what looks
to someone like me de Plaine, We say both s sounds,
so it's does planes. I guess I've lived here a
while now so that it actually confuses surprises me when

the phone directions say it in a more French correct way.
The town of Bourbonet, just how it's spelled, is pronounced Burboynes.
For real, she says, here's my friend's Bundy for pet tax.
That bunny as cute as pie. Oh oh, I haven't
been around rabbits a lot since I was a kid. Yeah,

and I both like them and have some mixed memories
about them being hard to cuddle, But my understanding from
friends that have rabbits, some are very cuddly, some are not,
just like any other animal. We also got an email
from our listener Caroline, who says same things. Should I've
been enjoying your podcast for so many years and have
attended one of your live events in Chicago before COVID,

and I'm very excited to see you both again soon
in Indianapolis. Quick note, you can, I think, still get
tickets for us at the Indiana Historical Society, so jump
on that if you're interested in seeing us live show
July nineteenth. Yes, and she continues, thank you so much
for making the history of everyone from everywhere so accessible

for all of us. As a longtime listener, I cannot
recall how many times you've mentioned how hard you both
work to pronounce people's names and place names correctly, and
I appreciate all of the hard work that goes into that.
So here's what I hope you'll read as a gentle correction.
A side note. You guys are so polite and sweet
about this. I love it. The email continues, I just
finished listening to the barbed Wire episode, and I got

very excited to hear the name of the city in
which my family and I live. I don't know if
you've already received emails or other communication about this episode
and the pronunciation of Decalb, which is so hard for
me to say. I'm just gonna laugh at myself for
a minute. Caroline continues, as a Decalb, Illinois residence, it
was a little distracting to hear the name of our

city in county pronounce the way it would be pronounced
in Georgia. Here we pronounce the L, so it comes
out sounding like the crossword puzzle word for a white
vestament worn by clergy alb. That may be confusing coming
from people in a state who do not want you
to say the final s in Illinois, but there it is.
We've lived here since two thousand and five, and both
my husband and I have attended NIU, which is the

normal school. Our children grew up here and know far
more about barbed wire and all of its history than
I will probably ever know. They were both marching barbs
for Decalb High School. We also have the Decalb Library,
which was sensitively renovated to retain much of the original building.
Attached are my pet taxes. Penny is the Blue Nose,
Pepper is the black Beauty. These are two of my

grand kitties, Ducky the Siamese Marmalade and Magpie the Burmese
best Carolyn, which I have been saying the wrong way.
I am obsessed with your dogs. Penny is so cute.
I'm like, I'm obsessed. This is the cutest picture of
Penny sleeping obsessed kitties. Black kitties, which we both love,

an orange kitty, which we both love. I love an
orange cat. That's on my wish list for future future
kitty acquisitions, as an orange baby because I haven't had
one yet. And this little sweet I mean, the face
that you would want to give all of the food
and snacks to Pepper is so cute. I feel like

if I were in your house, I would just spend
all my time kissing and hugging your animals. That sounds correct.
They may or may not want, which is the problem
that I have as a full time el my Reduff.
Thank you both for your gentle corrections. I will tell
you that I had a moment when I was listening
to the QA and I was like, oh, I think
they say that different in Illinois. But we have both

been traveling, and I was like, there's no way we
can get a pick up in this, so I'm just
letting it fly. So I had a moment before we
recorded where I was like, I feel like there's one
of the cabs that says it differently. Because there are
multiple places, they're all named after the same person. Even

though not everyone says it the same way. And normally
when there are different pronunciations for a place that is
spelled the same, when you go to four vo dot com,
they're all in there, yes, And in this case there
was only the cab. So uh like that was my because,

as you said, we both were traveling. We were trying
to get episodes recorded ahead of traveling, and that was
like my super quick check was at four voh and
fourvo only had one pronunciation, and I'm mentally moved on
with only to cab. We did get an email from
somebody who said who like noted specifically that they are
named after the same person, which reminds me of like Peabody,

Massachusetts named after George Peabody. Yeah, multiple things. Yeah, like
George Peabody is probably how he said his name, but
we like, no, don't really know, uh, but like it's
all over the place whether people pronounce things named after
him as Peabody or Peabody. So yeah, yeah, I chuck

this one up to the Star Wars thing of it's
both ad at and atat. Yeah, I don't have anything
further to add. My quick check ahead of time did
not yield the fact that they're that this was specifically

a place that says the L. Also, I will say,
and this is not to dog anyone's pronunciation, because we
all have I mean, listen, we live. I live still
in a city where the name Ponce de Leon is
Ponce de Leon. So like, this isn't I'm not I'm
not dogging anybody, and I live in Massachusetts. Who even
knows what we're doing? Right? Saying decab decalb is so

awkward from my mouth. Yeah, it's like we had gotten
that information correctly ahead of time. It might have been
a long record. It might have been a long record.
I think more likely there would have been times that
we pronounced it the way we have always pronounced it,
and then would have caught it in QA and we
would not have been able to fix it because of
our travel schedules. Yeah, because we have each been traveling

in Uh. You know, there becomes a point where it's
like I cannot record a podcast from my phone and
have it sound like the recording that was done in
a studio. Yeah, and it would just be a gigantic mess. Yes,
uh yeah, this is these are the perils of globe trotting.
This is also reminded me. Do you remember a movie

phone that you used to be? I don't know if
it's to be able to call and at the movie
phone the movie listings. When I was living in Atlanta,
movie phone would tell us the listings for AMC North
de Koll. But we were always like, what are you
saying it that way? Movie phone? Oh yeah. This is
one of my favorite things about GPS is how GPS
will pronounce things that aren't aren't the way anybody would

pronounce them in any jurisdiction. So sure, thank you for
being so kind and lovely in your corrections to both
of you. I really appreciate it. If you have email
you would like to send us, you can do that
at History podcast at iHeartRadio dot com. If you haven't
subscribed yet, you can do that as easiest pie, on
the iHeartRadio app, or anywhere you listen to your favorite shows.

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