Speaker 1: Welcome to Stuff You missed in History Class from how
Speaker 1: Stuff Works dot Com. Hello, and welcomed to the podcast.
Speaker 1: I'm Tracy B. Wilson and I'm probably from So. I
Speaker 1: did not intend for today to be a Halloween episode.
Speaker 1: Is scary. Yeah, due to some quirks in our publishing schedule,
Speaker 1: it happens to be coming out right before Halloween. It
Speaker 1: is a listener request from listener Ellen or perhaps Ellen,
Speaker 1: And in researching it, I realized it was the most
Speaker 1: frightening thing I had ever learned about. So, so buckle up.
Speaker 1: History has scared Tracy. History has scared Meat. So. From
Speaker 1: nineteen sixteen to about nine seven, this really bizarre epidemic
Speaker 1: spread around the world. It came to be known as
Speaker 1: sleepy sickness, and it is not to be confused with
Speaker 1: sleeping sickness, which is a tropical disease found in sub
Speaker 1: Saharan Africa. This is another name for a disease called
Speaker 1: encephalitis lethargica, and it caused this really weird variety of symptoms,
Speaker 1: from drastic behavior changes to unusual eye movements. Especially in
Speaker 1: the beginning years of it. Uh, the really common element
Speaker 1: was this deep, prolonged sleep that went on and on
Speaker 1: from days two months, and people just couldn't wake up.
Speaker 1: Between twenty and of the people who got this disease died,
Speaker 1: and of the ones who survived, only about a third
Speaker 1: really fully recovered. The rest developed what came to be
Speaker 1: known as post and syphilitic parkinson ism, and some of
Speaker 1: these patients persisted in a semi comatose state for decades.
Speaker 1: It's extra terrifying. The next part is even more terrifying. Yeah,
Speaker 1: As if all of this were not enough to scare
Speaker 1: the pants off of you. While in this extremely deep sleeps,
Speaker 1: it was part of many of the aces. People appeared
Speaker 1: to be unconscious, but in reality they were actually alert.
Speaker 1: They were completely aware of what was going on, but
Speaker 1: they were unable to move or speak, so it was
Speaker 1: a sort of paralysis. Really. Yeah, So people today may
Speaker 1: have heard about this whole disease from the movie Awakenings
Speaker 1: starring Robin Williams, or maybe from the first pages of
Speaker 1: Neil Gaiman's amazing comic book series Sandman, which starts off
Speaker 1: when a ritual that was meant to capture death instead
Speaker 1: captures dream and causes people to sleep endlessly. Otherwise, it's
Speaker 1: pretty far in the background of medical history most of
Speaker 1: the time. It's not something that people remember all that
Speaker 1: well today, but from its onset until about ten years
Speaker 1: after it faded away, there were more than nine thousand
Speaker 1: papers and books published on it, So at the time
Speaker 1: it was a big deal, even though people don't necessarily
Speaker 1: come up with it immediately when thinking about huge epidemic today. Yeah,
Speaker 1: and I wonder why that is ull talk about some
Speaker 1: of that. Yeah, Prolonged sleep as an illness has been
Speaker 1: reported really really way back into history. There are written
Speaker 1: records as early as Hippocrates of this kind of incident happening.
Speaker 1: And then there are also, of course in our cultural
Speaker 1: consciousness tales like sleeping beauty and these stories like ripped
Speaker 1: van Winkle uh, and some people along the line have
Speaker 1: theorized that these were actually rooted to some degree in
Speaker 1: some kind of sleeping illness. In the real world, there
Speaker 1: had also been an outbreak of a similar condition in
Speaker 1: Italy in eighteen eighty nine and eighteen ninety, which came
Speaker 1: to be known as Landona, and it was thought at
Speaker 1: the time to be a complication of the flu. And
Speaker 1: around the world other outbreaks of encephalitis had also followed
Speaker 1: behind other epidemics, particularly the flu. This particular one started
Speaker 1: just a couple of years before the nineteen eighteen Spanish
Speaker 1: flu epidemic, which killed between twenty and forty million people,
Speaker 1: and when it came to the encephalitis lethargica epidemic, the
Speaker 1: first reports came at about the same time in different
Speaker 1: two different places, which were France in Austria. In nineteen
Speaker 1: six in France, a doctor named Genrene Cruche started to
Speaker 1: see six soldiers with this weird assortment of seemingly unrelated
Speaker 1: neurological symptoms, and the one common element was that the
Speaker 1: patients just slept, apparently peacefully and deeply, and that they
Speaker 1: could not be woken up, and he started to wonder
Speaker 1: whether there was some kind of new chemical weapon at work.
Speaker 1: At about the same time, a British doctor named A. J.
Speaker 1: Hall also reported similar symptoms, and other troops who were
Speaker 1: stationed in France. In Vienna, it came to the attention
Speaker 1: of Romanian Austrian psychiatrists Constantine von Economo after a sleepy,
Speaker 1: disoriented civilian wandered into the Wagner Jarre clinic where he worked.
Speaker 1: The doctor's there had mostly been treating soldiers who were
Speaker 1: wounded in the war, so they really weren't prepared for
Speaker 1: this apparently uninjured civilian with nothing physically wrong that they
Speaker 1: could really point to. And then more and more patients
Speaker 1: with similar symptoms arrived at the clinic, and there you know,
Speaker 1: they had the similar part of this uncontrollable sleepiness and sleep,
Speaker 1: but the rest of their symptoms were so strange and
Speaker 1: diverse that the doctors were really at a loss to
Speaker 1: figure out a cause or a treatment. These patients had fevers, malaise,
Speaker 1: double vision, they became lethargic. Sometimes they had sore throats.
Speaker 1: Their eye muscles would start working and their eyes would
Speaker 1: dart around or roll back in their heads. Some of
Speaker 1: them developed very strange eye and tongue movement movements, and
Speaker 1: this variety of other neurological and psychiatric symptoms. A few
Speaker 1: of them even had uncontrollable hiccups and one died of that.
Speaker 1: How that work. Well, if you can't stop pickuping, you
Speaker 1: can't really eat or sleep, and then it can cause
Speaker 1: all kinds of other Yeah. Once again, throughout all of this,
Speaker 1: the common element was this strange deep sleep from which
Speaker 1: they could not be woken. Vanni Conomos saw this common
Speaker 1: element and said, we're dealing with a sleeping sickness. Yeah,
Speaker 1: he was really the one that just laid that out there,
Speaker 1: and he's a character on his own. He was also
Speaker 1: a pilot who had been serving in the war, but
Speaker 1: he came back home to Vienna after his brother was
Speaker 1: killed and he really wanted to be flying, but reluctantly
Speaker 1: transferred to doing medical work instead to try to keep
Speaker 1: himself more out of danger and spare his family from
Speaker 1: further grief. On top of all that, he was also
Speaker 1: a baron, having been born to a family of Greek
Speaker 1: aristocrats and then married the daughter of an Austrian prince.
Speaker 1: As the patient started to die from sleep, Vonni Konomos
Speaker 1: started an intense research effort to find a cause and
Speaker 1: a cure. He studied autopsies of patients who had died
Speaker 1: of the disease, and he found common areas of damage
Speaker 1: to their brains, specifically in the hypothalamus, and he suspected
Speaker 1: that the differences and how much people slept was related
Speaker 1: to just how their hypothalamus was damaged. He also found
Speaker 1: that brain tissue could transmit the disease to monkeys, so
Speaker 1: he concluded that they were looking at something that was contagious.
Speaker 1: He publicly announced his conclusion that they were dealing with
Speaker 1: a new disease, probably a virus, before the Psychiatric Society
Speaker 1: in Vienna, on April seventeenth of nineteen seventeen. UH. Consequently,
Speaker 1: sometimes the disease has been referred to as von Economo's disease.
Speaker 1: His announcement was not at all well received. At a
Speaker 1: time the prevailing view with that mental illnesses were all
Speaker 1: products of things like trauma and buried memories. Freud was
Speaker 1: really at the forefront of psychology at this point, so
Speaker 1: a lot of people just scoffed at the idea that
Speaker 1: there could be a virus or other disease process causing
Speaker 1: the kinds of behavior changes in psychological problems that some
Speaker 1: of the patients were exhibiting. The ongoing debate and this
Speaker 1: mystery of the whole thing kept much progress from being
Speaker 1: made in terms of treatment and prevention. But then UH,
Speaker 1: the illness mostly disappeared from continental Europe. It really just
Speaker 1: fell off suddenly, and Spanish flu on the rise took
Speaker 1: its place and it became a much more pressing priority.
Speaker 1: Not long after that, though, the disease appeared in London
Speaker 1: and it followed much the same pattern as it had
Speaker 1: on the continent. There were, you know, all these patients
Speaker 1: who were suddenly having this strange collective collection of symptoms
Speaker 1: and sleeping constantly. The government in Britain quickly made it
Speaker 1: a reportable disease. The Ministry of Help had to be
Speaker 1: notified of all new cases, and its appearance and spread
Speaker 1: uh in London was much like it had been in
Speaker 1: France and Austria. Strange symptoms and unending sleep uh, you know,
Speaker 1: baffling the doctors. But in England the symptoms became even
Speaker 1: more alarming, with patients who could never sleep, or who
Speaker 1: couldn't stop laughing, or had other strange physical or emotional presentations.
Speaker 1: It also seemed like fewer and fewer people were truly recovering.
Speaker 1: In Austria and France, there had been people that had
Speaker 1: gotten better, but as it's spread around England, a lot
Speaker 1: of people were becoming comatose or developing. As we mentioned
Speaker 1: at the beginning, what later came to be known as
Speaker 1: post en syphilitic parkinson is um or PEP. Sometimes the
Speaker 1: onset of parkinson is um happened years after people recovered,
Speaker 1: after they had apparently been healthy all that time. During
Speaker 1: the epidemic, the average age for the onset of Parkinson's
Speaker 1: dropped to thirty six years old. Today, while there are
Speaker 1: people who have early onset, the average age for people
Speaker 1: to start exhibiting Parkinson's is sixties. So this was really
Speaker 1: a significant and strange happening. Uh following the epidemic, two
Speaker 1: thirds of Parkinson's patients had previously had encephalitis, so it
Speaker 1: clearly was causing it right, This disease was causing a
Speaker 1: drastic shift in who developed Parkinson's and when. So, to
Speaker 1: return to the story of encephalitis Letharctica from England, the
Speaker 1: disease spread all over the globe, and the same story
Speaker 1: just played out over and over and over. People would
Speaker 1: start showing up with these strange symptoms that prevent that
Speaker 1: presented themselves in such different ways that it would take
Speaker 1: a while for doctors to realize what was happening. It
Speaker 1: really didn't help that the epidemic had started just at
Speaker 1: the end of World War One and just before the
Speaker 1: start of the nineteen eighteen Spanish flu epidemic, and so
Speaker 1: resources were just scarce and there were definitely bigger priorities
Speaker 1: going on, and this crazy although terrifying disease, and as
Speaker 1: it spread it started to prompt a variety of different
Speaker 1: sleep disorders, so while some patients would sleep for months
Speaker 1: at a time, others couldn't sleep at all, and they
Speaker 1: would actually die of exhaustion. The disease came to be
Speaker 1: known in some places as epidemic encephalitis rather than encephalitis lethargica,
Speaker 1: since not everyone could really be called lethargic anymore. As
Speaker 1: it spread, it also started to affect more and more
Speaker 1: children and young people. Children who contracted the disease developed
Speaker 1: impulse control issues that led to them having violent behavior
Speaker 1: in their adolescence. Some of them injured themselves or other people.
Speaker 1: One even removed her own eyes and several of her
Speaker 1: own teeth okay after I unclenched after that um, this
Speaker 1: behavior often would continue for the rest of these patients
Speaker 1: lives after they progressed out of childhood, unless post and
Speaker 1: cephalitic parkinson is M made them physically unable to continue.
Speaker 1: For children with the disease, outbursts were so severe that
Speaker 1: many had to be institutionalized. Hospitals and asylums that were
Speaker 1: accustomed to providing care for adults suddenly had to develop
Speaker 1: new practices to care for children because there were so
Speaker 1: many suddenly having a movement institutions. Researchers theorized that the
Speaker 1: reason this encephalitis was causing behavior changes like this and
Speaker 1: young people was because their brains hadn't yet developed the
Speaker 1: capacity for self control that adults typically had by the
Speaker 1: time they were infected, and this tendency towards violent behavior
Speaker 1: and other erratic behavior even led to encephalitis lethargica being
Speaker 1: blamed for gangster behavior and lawlessness during the nineteen twenties.
Speaker 1: Once this disease spread to the United States, neurologist Frederick Tilney,
Speaker 1: who was known as Fred and had also been Helen
Speaker 1: Keller's neurologist, became the country's foremost authority on sleepy sickness.
Speaker 1: One of his most famous encephalitis patients was Jesse Morgan,
Speaker 1: who was the wife of Jack p Morgan, who himself
Speaker 1: was the son of banker and philanthropist John Pierpoint Morgan.
Speaker 1: She got the disease in ninety five. Five. After Jesse's death,
Speaker 1: Jack donated two hundred thousand dollars to the Neurological Institute
Speaker 1: the fund research into this disease. The Neurological Institute was
Speaker 1: behind most of the research into encephalitis authargica that came
Speaker 1: from that point. Later on, William Matheson, who was the
Speaker 1: wealthy founder of a chemical company and an encephalitis patient,
Speaker 1: started the Matheson Commission to fund research at the Neurological Institute,
Speaker 1: with Dr Josephine B. Neil, who was an encephalitis expert,
Speaker 1: helming the project, and the commission's aim was to study
Speaker 1: the disease and eventually find a vaccine. Since nobody knew
Speaker 1: exactly what was causing the disease, they worked on three
Speaker 1: theories simultaneously. One was that it was being caused by
Speaker 1: an unknown virus, the next was that it was being
Speaker 1: caused by bacteria, possibly strap uh, and the third was
Speaker 1: that it was being caused by herpes. This was a
Speaker 1: long shot to begin with because no causative agent had
Speaker 1: been found for this disease. They were basically operating in
Speaker 1: the dark based on best guesses. On top of that,
Speaker 1: there was a ton of infighting among the researchers. A
Speaker 1: lot of them were extremely prominent neurologists and scientists. Each
Speaker 1: of them really wanted to be the one to crack
Speaker 1: this case and figure out what's going on um that
Speaker 1: they were not working together very well. They were each
Speaker 1: trying to get the glory for themselves. And then there
Speaker 1: was another huge setback when Matheson himself died in nineteen thirty.
Speaker 1: That was in the middle of the Great Depression, and
Speaker 1: he had been providing the funding, so after his death
Speaker 1: there wasn't really other funding to be had, so the
Speaker 1: Matheson Commission ceased operations in two and so no workable
Speaker 1: vaccine had been developed, and one of the things that
Speaker 1: doctors tried to treat post and cephalitis patients with was lobotomies,
Speaker 1: which also did not work. There was a lot of
Speaker 1: ending that did not work. There were a few outlying
Speaker 1: successes during this time that we kind of give people
Speaker 1: false hope that maybe they were on the right track,
Speaker 1: but nothing led to an actual treatment or cure. Most
Speaker 1: of the medical care that the patients were receiving was
Speaker 1: really about just caring for their bodies and keeping them alive.
Speaker 1: The thirty or so percent who developed parkinson is um
Speaker 1: generally wound up in long term care for the rest
Speaker 1: of their lives, and many of them were completely unable
Speaker 1: to move or take care of themselves in the nineteen sixties,
Speaker 1: after the drug love Adopa or el dopa as it
Speaker 1: was called, was introduced for treating Parkinson's. New York doctor
Speaker 1: Oliver Sachs, who are some of our listeners may have
Speaker 1: heard of, administered it to some encephalitis lethargica patients who
Speaker 1: were in long term care. Some patients actually showed a
Speaker 1: limited recovery from their post and sephalitis lethargica Parkinson symptoms. Uh.
Speaker 1: This is the story that's actually told in the movie Awakenings,
Speaker 1: which is why people may have heard of all over sex.
Speaker 1: But they all apparently developed a tolerance until the dosage
Speaker 1: was really just too much for the human body to handle,
Speaker 1: and then they would return to their semi comatose state
Speaker 1: in the end. This epidemic went on from nineteen sixteen
Speaker 1: to nineteen twenty seven, reaching its peak in nineteen twenty four,
Speaker 1: after which the number of cases started to drop off.
Speaker 1: The total numbers of people affected are really unclear. There
Speaker 1: are sources who say that a million people were killed,
Speaker 1: while others say that only half a million were affected
Speaker 1: in one way or another. Regardless, though the mortality rate
Speaker 1: was pretty serious in England, almost half of the cases
Speaker 1: in nineteen nineteen and nineteen twenty died. Although it was
Speaker 1: roughly concurrent with the Spanish flu pandemic, and flu came
Speaker 1: up frequently when looking at possible causes, many doctors at
Speaker 1: the time didn't really think the disease was actually flu related.
Speaker 1: Only a small percentage of the patients had also had
Speaker 1: Spanish flu, and teen eighty two, however, doctors from the
Speaker 1: Centers for Disease Control published this list of connections between
Speaker 1: the two diseases. So for a little while. In more
Speaker 1: recent years, flu became a prime suspect for causing encephalitis lethargica.
Speaker 1: Uh there is, you know, especially since there have been
Speaker 1: other incidents of encephalitis that have followed outbreaks of the flu. Today,
Speaker 1: the idea that the flu was the culprit has pretty
Speaker 1: much been ruled out thanks to modern testing methods. They
Speaker 1: haven't turned up any sign of the flu virus in
Speaker 1: tissue samples from patients who died from encephalitis, Although it's
Speaker 1: never reached that same epidemic state again, isolated cases of
Speaker 1: encephalitis lethargica have continued to crop up even in recent years,
Speaker 1: most recently in a twenty three year old named Becky
Speaker 1: Powell was diagnosed with the disease and it took her
Speaker 1: two years to recover. Several similar cases followed. In two
Speaker 1: thousand three, a team of doctors public a paper in
Speaker 1: the journal Brain that put forth a pretty good case
Speaker 1: that the cause of encephalitis lethargica is actually a massive
Speaker 1: autoimmune reaction to an unidentified pathogen. A strain of strap
Speaker 1: comes up in the discussion, but it's ultimately dismissed as unlikely.
Speaker 1: And their research was done on twenty different patients who
Speaker 1: developed the disease between two thousand two, and those patients
Speaker 1: had a much lower mortality rate than during the epidemic.
Speaker 1: Only one died, but five of them did have to
Speaker 1: be placed on a ventilator. Had those five patients lived
Speaker 1: in the ninety twenties, they probably would not have made it,
Speaker 1: but almost none of them had fully recovered a year
Speaker 1: or so later when the paper was published. They continued
Speaker 1: to have neurological and psychiatric symptoms. Yeah. If if there
Speaker 1: had been if today's ventilation technology had existed in the
Speaker 1: nineteen twenties, the mortality rate would have been Yeah, because
Speaker 1: people would get into this just deep uninterrupted sleep and
Speaker 1: their respiratory functions would fail, and there wasn't really anything
Speaker 1: that people could do about it. But now that we
Speaker 1: have violators UH, that there are actual there's a treatment
Speaker 1: for that part of it that didn't exist back then.
Speaker 1: In paper in the journal BMC Infectious Diseases reported that
Speaker 1: a team of researchers had found virus like particles in
Speaker 1: the brains of both epidemic encephalitis patients and modern patients,
Speaker 1: so people who had died UH either recently or during
Speaker 1: the epidemic. This supports the idea that the cause of
Speaker 1: encephalitis lethargica is an interarovirus, but exactly what interovirus we
Speaker 1: still do not know. And on that note, so encephalitis
Speaker 1: lethargica has a some you know, a legacy today, even
Speaker 1: though a lot of people have not really heard of
Speaker 1: it as tragic and frightening as the disease was and
Speaker 1: is really. In the end, it helped doctors understand more
Speaker 1: about the brain. Von economist conclude Usian about the hypothalamus
Speaker 1: and its role in the patients sleep, for example, was
Speaker 1: hugely unpopular at the time, but many years later it
Speaker 1: was proved to be true after we developed sorts of
Speaker 1: imaging technologies that we can use to look directly at
Speaker 1: the brain as it's working today. Neurologist Bernard Sacks also
Speaker 1: wrote that the epidemic of encephalitis quote revolutionized the practice
Speaker 1: of neurology. So it really changed the way that, uh,
Speaker 1: these things were examined from the get go. Yeah, it
Speaker 1: helped solidifying neurology as an actual field. In the early days,
Speaker 1: there was sort of this hodgepodge of neurology ideas and
Speaker 1: psychology ideas and all these things that were kind of
Speaker 1: together in one big pot. And in part because of
Speaker 1: encephalitis being spread the way that it was, a group
Speaker 1: of doctors branched off to study just neurology and encephalitis.
Speaker 1: Lethargica was also one of the conditions that made it
Speaker 1: clear that disease process says, can lead to mental illnesses. Uh,
Speaker 1: it's solidified the idea that mental illnesses were not solely
Speaker 1: in the realm of emotions or traumatic experiences. It's not
Speaker 1: always buried memories. Sometimes there can actually be a physical
Speaker 1: happening that causes mental illness. There are a couple of
Speaker 1: books that are out about this epidemic. The one that
Speaker 1: I read researching. This podcast was called Asleep, The Forgotten
Speaker 1: Epidemic that remains one of Medicine's greatest mysteries by Molly
Speaker 1: Caldwell Crosby and her grandmother survived Sleepy Sickness. It starts
Speaker 1: with sort of a case study of her grandmother. That's
Speaker 1: terrifying because it's about her grandmother being asleep for so long,
Speaker 1: but also being aware of what was happening around her,
Speaker 1: which to me is just terrifying. The one caveat about
Speaker 1: this book is that it was written before the very
Speaker 1: most recent research about what might have caused this particular epidemic,
Speaker 1: which is going to be the case which just about
Speaker 1: every book now since the latest research is just very new. Yeah.
Speaker 1: Last year, as we were recording, I have read several
Speaker 1: papers that, uh, you know, and when the bird flew
Speaker 1: epidemic was was everybody was very frightened about bird flu.
Speaker 1: There were several articles that that came up where doctors
Speaker 1: were like, actually, what you really should be afraid of
Speaker 1: is a resurgence of this still unidentified encephalitis that sometimes
Speaker 1: sometimes follows outbreaks of other diseases. I yeah, it's basically
Speaker 1: my worst nightmare. I mean, I have not a good
Speaker 1: relationship with sleep anyway. If I didn't have to do it,
Speaker 1: I wouldn't. So the idea of not having any control
Speaker 1: over the situation and just being asleep but not really
Speaker 1: because you're conscious of things happening around is my worst nightmare. Yeah,
Speaker 1: not to play on sleep jokes, but well, it's terrifying
Speaker 1: and the there are many things about this whole, the
Speaker 1: epidemic and the illness itself that are are frightening to me,
Speaker 1: And one of them is that people would seem to
Speaker 1: recover and they would be fine for a long time,
Speaker 1: and then they developed, yeah, developed parkinson symptoms um and
Speaker 1: once it had been established that that was a pattern,
Speaker 1: I can imagine like the people who had gotten better
Speaker 1: really being like I'm never going to be which I
Speaker 1: know that's the case with a lot of diseases that
Speaker 1: people have now, Like there are many cancer patients who
Speaker 1: never feel like they are in the clear because you
Speaker 1: can be intermission. So yeah, it's a scary thing to
Speaker 1: live with that kind of over you cheerful it is.
Speaker 1: Do you have listener mail? The cheer aside, do have
Speaker 1: listener mail? And actually the first listener mail that I
Speaker 1: have is very cheerful. I have two of them. One
Speaker 1: of them is short. The first one is from Vince,
Speaker 1: and he says, Dear Tracy, thank you for helping me
Speaker 1: through some boring work days. During your recent podcast on
Speaker 1: Louis Alvarez, you mentioned all the Berkeley Nobel laureates from
Speaker 1: its past. Being a proud alum, I had recently had
Speaker 1: a chance to visit Berkeley, and strolling around the campus,
Speaker 1: I noticed this cute photo op between the two physics buildings,
Speaker 1: and basically he attached a picture of this row of
Speaker 1: prime parking spaces that all are like this space is
Speaker 1: for a novel, a Nobel laureate. So Nobel laureates get
Speaker 1: awesome reserved parking at Berkeley. They deserve it. They've probably
Speaker 1: lost a lot of time in their lives to work
Speaker 1: very hard on very difficult problems. Yeah. There there are
Speaker 1: a lot of spaces, and they are right by building.
Speaker 1: Says for me. It truly illustrates how good Berkeley research
Speaker 1: really is. Thanks again, Vince, Thank you, Vince. I love
Speaker 1: that picture. Yes, okay, the other one is from Sarah,
Speaker 1: and I'm going to just start with a confession that
Speaker 1: I worried that when we were talking about Luis Alvarez
Speaker 1: that we were talking too much about how hard a
Speaker 1: lot of his discoveries are to understand if you are
Speaker 1: not also a physicist. So I particularly liked this letter
Speaker 1: from Sarah. Sarah says, Hi, Holly, and Tracy. I'm a
Speaker 1: graduate student at m I T and i love listening
Speaker 1: to your podcast when I set up reactions in our
Speaker 1: nitrogen filled glove box or washed my glassware. I just
Speaker 1: listened to your podcast on Luis Alvarez, and I wanted
Speaker 1: to thank you for all the podcasts you've done which
Speaker 1: touch on science, even though for the purposes of this episode,
Speaker 1: I'm a chemist and not a theoret radical physicist. I
Speaker 1: find your descriptions clear and engaging, which is so rare
Speaker 1: fined in science communication. I have a small correction to
Speaker 1: make on your last episode where you mentioned that the
Speaker 1: temperature of liquid hydrogen is degrees below zero celsius. I
Speaker 1: think you meant minus two fifty three degrees celsius, since
Speaker 1: absolute zero zero kelvin is minus two seventy three degrees celsius.
Speaker 1: At this point, molecules cease to have entropy, and it
Speaker 1: is the coldest possible temperature, so liquid hydrogen is twenty kelvin,
Speaker 1: which is still really really cold, but not as clear
Speaker 1: as liquid helium, which is for kelvin. Also, I was
Speaker 1: interested in hearing the cheek lub crater mentioned. I studied
Speaker 1: odd in the Yucatan Peninsula in college and visited the
Speaker 1: town of chik Lube several times. But it was only
Speaker 1: after I got back to the States that I saw
Speaker 1: that twenty ten science paper that you mentioned and realized
Speaker 1: that I had been in the impact site probably responsible
Speaker 1: for the mass extinctions without knowing it. By the way,
Speaker 1: you got the pronunciation pretty close, but it's actually pronounced
Speaker 1: more like cheek salub. The x mention s h sound
Speaker 1: apparently means something like lee devil according to Wikipedia. In
Speaker 1: any case, it was amazing to have the chance to
Speaker 1: study there. So much of the Mayan culture and the
Speaker 1: language is preserved in the Yucatan. And then Sarah recommends
Speaker 1: h subject for us to talk about, which we're just
Speaker 1: going to save in case we're able to do that
Speaker 1: in a later podcast, and she says, anyway, sorry this
Speaker 1: email got so long, but I wanted to thank you
Speaker 1: guys for your science recording. Keep up the good work, Sarah,
Speaker 1: thank you so much. Sarah. Yeah, we got a few
Speaker 1: corrections on the temperature thing we did. I would like
Speaker 1: to thank Sarah's correction for being very nice about it.
Speaker 1: There were a couple of people who needed to tell
Speaker 1: us that corrections are bad and that mistakes are bad,
Speaker 1: and we know that we try our best. So yes,
Speaker 1: that is totally either a typo in my notes or
Speaker 1: a typo and something I was making notes from. So
Speaker 1: thank you very much for clarifying just how extremely extremely
Speaker 1: cold liquid hydrogen is. Thankfully we did not work in
Speaker 1: a lab where there would be actual scary implications of
Speaker 1: us making the error of that magnitude. Yes, we're safe.
Speaker 1: It's just words. It's just words, and we're edited though
Speaker 1: it's kind of her job. But yeah, occasionally we do
Speaker 1: get stuff wrong in spite of our best effort. So
Speaker 1: thank you so much, Sarah. I am so glad to
Speaker 1: hear from science people who enjoy us talking about science,
Speaker 1: because I do love science, but because it is not yes,
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