The Accidental Discovery of Radioactivity

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In this installment on the history of the atom theory, physics professor (and my dad) Dean Zollman tells the surprising story of how radioactivity was discovered. After reading this post, I wondered “What if the weather had been good in Paris?” – Kim

By Dean Zollman

Dean Zollman

During the short time between 1895 and 1897, three important discoveries helped define physics of the 20th century. We have looked at two of them –the electron and x-rays – in the past two posts. This month, we will discuss the third – radioactivity.

As I mentioned last time, news of Wilhelm Roentgen’s discovery of x-rays at the end of 1895 spread rapidly through both the scientific and general communities. This new form of electromagnetic radiation was the subject of discussion at the meeting of the Academy of Sciences in Paris on January 20, 1896. Henri Poincaré (1854-1912) noted that the x-rays seemed to be emitted at a point in the Crooke’s Tube where some light was being emitted by fluorescence – a process similar to the way fluorescent tubes work today. Poincaré wondered if other substances that emit light might also emit x-rays. In particular he mentioned types of minerals which glowed in the dark after being exposed to sunlight – a process called phosphorescence. (Many of the glow-in-the-dark objects that we have today emit light by phosphorescence. They store energy in their atoms when exposed to light and then reemit that light gradually over a long time.) A. Henri Becquerel (1852-1908) decided to see if Poincaré’s conjecture might be correct.

Henri Becquerel, Library of Congress

Becquerel was in a good position to conduct the necessary experiments. He was professor of applied physics at the Museum of Natural History in Paris. The two previous professors to hold this position were his father, Alexandre Edmond Becquerel (1820-1891), and his grandfather, Antoine César Becquerel (1788-1878). (Later, Henri’s son would also hold the professorship. So it was a four-generation dynasty.) Both of the senior Becquerels conducted research on phosphorescent materials. So, Henri had a laboratory with a large collection of minerals that had the glow-in-the-dark property. In addition, Henri’s father had experimented with the relatively new process of photography. So, Henri understood this process which, as we shall see, is very important to the discovery.

X-rays were known to penetrate materials that ordinary light could not pass through. Henri Becquerel realized that he could take advantage of this property. A photographic plate could be wrapped in heavy black paper so that no light could reach it. He could then place a material that he thought might emit x-rays next to the wrapped plate. X-rays would pass through the black paper and expose the plate. Then when Becquerel developed the plate, he would see a black area exposed to x-rays.

From his own work as well as that of the previous generations, Becquerel understood that the only pure phosphorescent materials known at that time were salts of uranium. So, he used potassium uranyl sulfate for his experiments. He exposed the material to sunlight, placed it on a photographic plate for a while and then developed the plate. His experiment, he thought, was a success; the photographic plate had a black area on it even though the plate had never been exposed to light. Becquerel’s conclusion was that the uranium salt had emitted x-rays.

He could not explain the mechanism for this process, but it seemed as if exposure to sunlight created some type of change in the salts and that change resulted in the emission of x-rays. On February 24, 1896, Becquerel reported his results to the weekly meeting of the Academy of Sciences in Paris. He promised to conduct more experiments and report more results the following week.

Then the French winter weather interfered in an incredibly positive way. Most of the next week in Paris was very cloudy. Becquerel could not expose his uranium salts to sunlight. He put the uranium salts and the photographic plates in a drawer where they sat and had no exposure to any type of light.

So, these plates should have shown nothing remarkable. In fact, there should have been no reason to even develop them. But on Sunday, March 1, 1896 (119 years ago this week), Henri Becquerel developed these never exposed plates. One of the results is shown below.

Photographic plate by Henri Becquerel

The exposure was just as strong as that of the plate from the previous week. The radiation emitted by the uranium salts did not depend on exposure to the sun and was different from x-rays.

One of the mysteries in the history of science is why Becquerel developed these plates. Apparently, he did not reveal his reasons, so he left something for historians of science to speculate about. Some think he was just being frugal; no sense in wasting the plate. The plates get old, but the chemicals can be reused. Others have thought that he wanted to make sure that his developing chemicals had not become too old.

The most plausible idea (at least to me) is that he had promised new results for the Academy of Sciences meeting on Monday, March 2. He was hoping that he would see at least a weak exposure so he could report something, even though it would not be very interesting. Instead, he was able to report an extremely interesting result.

Becquerel conducted some additional experiments and during 1896 reported on the properties of this radiation, which later came to be called radioactivity. A few of his observations turned out to be wrong, but others helped people understand how this radioactivity was different from x-rays.

Unlike x-rays, radioactivity generated no great excitement in the scientific community. Even Becquerel seemed to tire of them quickly. He published seven papers on the topic in 1896, one in 1897, and none in 1898. He was off investigating other things. (In 1896 alone, more than 1,000 about x-rays papers were published.)

This situation would change when Marie Skłodowska Curie (1867-1934) and Pierre Curie (1859–1906) began a systematic study of radioactivity. I will save that story for next time. (If you want to get ahead of my story, I recommend the 1943 film Madame Curie starring Geer Garson and Walter Pidgeon. It is history according to Hollywood but still somewhat fun.)

All images are public domain, via Wikimedia Commons.

Dean Zollman is university distinguished professor of physics at Kansas State University where he has been a faculty member for more than 40 years. During his career he has received four major awards — the American Association of Physics Teachers’ Oersted Medal (2014), the National Science Foundation Director’s Award for Distinguished Teacher Scholars (2004), the Carnegie Foundation for the Advancement of Teaching Doctoral University Professor of the Year (1996), and AAPT’s Robert A. Millikan Medal (1995). His present research concentrates on the teaching and learning of physics and on science teacher preparation.

Previously

What Are Things Made of? Depends on When You Ask.

Ancient Greeks Were the First to Hypothesize Atoms

The Poetry of Atoms

Atom Theory in Ancient India

Religion, Science Clashed over Atoms

Medieval Arabic Scholarship Might Have Preserved Scientific Knowledge

Rediscovering a Roman Poet – and Atom Theory – Centuries Later

Reconciling Atom Theory with Religion

Did Atom Theory Play a Role in Galileo’s Trouble with the Inquisition?

Did Gifted Scientist’s Belief in Atoms Led to His Obscurity?

Does Atom Theory Apply to the Earthly and the Divine?

A Duchess Inspired by Atoms

Separating Atoms from Atheism

Isaac Newton: 300 Years Ahead of His Time

Issac Newton and the Philosopher’s Stone

When Chemistry and Physics Split

Redefining Elements

Mme Lavoisier: Partner in Science, Partner in Life

With Atoms, Proportionality and Simplicity Rule

Despite Evidence of Atoms, 19th Century Skeptics Didn’t Budge

Mission of the First International Scientific Conference: Clear up Confusion

Rivalry over the First Periodic Table

The Puzzle of Dark Lines amid Rainbow Colors

The Colorful Signature of Each Element

Light Waves by the Numbers

Even Scientific Dead Ends Can Contribute to Knowledge

Discovery of the Electron Took Decades and Multiple Scientists

‘Wonders of the X-ray’

Walburga and Her Family Ties

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By early medieval standards, Saint Walburga had a cushy lifestyle at the double monastery of Wimbourne.

Well, strictly following the Rule of Saint Benedict is hardly a life of luxury, but this daughter of a West Saxon under-king was in a safe place and could be reasonably certain of when she would eat. She would pray at the bells, pursue her studies, and do chores assigned to her.

But when she was in her late 30s, far from young by the standards of her time, her maternal uncle Saint Boniface asked her and other nuns to uproot their lives for the sake of Christianity in today’s Germany.

For more about Walburga, read my post on English Historical Fiction Authors.

Saint Walburga

A 19th century painting of St. Walburga (public domain image via Wikimedia Commons).

A Post-Soviet Princess’s Autobiographical Satire

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Today it’s my pleasure to host my friend author Marina Julia Neary on Outtakes as she introduces her latest release, Saved by the Bang, based on her experience growing up after the disaster at Chernobyl. Her book is an eye-opener, especially for those of us who remember the Cold War (for more, read my review). – Kim

By Marina Julia Neary

Marina Neary author photoAfter years of being nagged by my readers, I finally wrote something autobiographical (God forbid!) Most of my fiction deals with the Anglo-Irish conflict, even though I’m not Irish by blood. I spent the first 13 years of my life in Belarus, a former Soviet Republic, which is now a sovereign country that has managed to stay out of world news. Nothing remarkably good or bad happens there.

The last major tragedy dates back to 1986, when one of the reactors blew up in Chernobyl across the Ukrainian border, drenching Belarusian cities in raw radiation. The full scope of the damage was not communicated to population to prevent an outbreak of panic. The authorities could not stop the flow of radiation, so they stopped the flow of information.

Chernobyl sign

2013 photo by Paweł “pbm” Szubert via Wikimedia Commons, used under the Creative Commons Attribution-Share Alike license (CC-BY-SA-3.0)

Almost 30 years later, people are still paying the price. Leukemia, lymphoma, thyroid cancer, and birth defects will continue to afflict the generations to come. Since I as an author specialize in disasters, I decided that my next novel would deal with one that I had experienced firsthand. It’s an opportunity for me to showcase my dark humor. As one of the reviewers mentioned, the novel is “not for the faint of heart.” Some readers will be disturbed and offended by the fact that I inject so much humor into my narrative depicting such tragic events.

The joke is that every Chernobyl story has to feature a girl named Maryana, just like any Jane Austen novel has to feature a girl named Elizabeth. Maryana was the name my biological father had originally picked out for me. He liked the archaic, folksy, old pan-Slavic slant. My mother hated it for those very reasons, so they settled on a more cosmopolitan Marina. Maryana is my alter ego, a privileged yet suffering child with a Jewish heritage, a lonely, old soul watching the world around her quietly slip into chaos.

The City of Swans and Violets

Much of the action takes place in Gomel, a squeaky-clean, low-key riverfront city famous for its gorgeous flower beds and summer folk concerts. The city’s coat of armor shows a muscular bobcat, a trademark Belarusian animal.

Panorama of Gomel

Panorama of Gomel, by Dennis Sviridenko

During World War II Gomel was occupied by the Nazis, and 80 percent of the city was destroyed. Luckily, the most prominent landmarks like the Rumyantsev-Paskevich Palace compound and the gorgeous Orthodox church were spared. The city has everything to satisfy an average person’s intellectual and cultural appetites. There are several universities, a drama theater, a swan pond, museums, and countless cinema art houses.

Of course, there will always be those who’ll wrinkle their noses and say that Gomel is a provincial hole. But guess what? Not everyone can live in Moscow or St. Petersburg. As far as medium sized cities were concerned, Gomel offered enough opportunities to work and play. Growing up, I don’t remember being bored. Children had an ample selection of educational activities. Art, music, and dance lessons were accessible and affordable.

I’ve been asked on several occasions, “So what it was like to live behind the Iron Curtain?” Personally, I’ve never experienced the horrors of draconian censorship. By 1980s, most people had grown disillusioned with the Communist ideal so successfully force-fed to them in the previous decades. It was still customary to celebrate Communist holidays like the October Revolution Day (which actually falls on November 7, according to the new calendar) and Workers’ Solidarity Day (May 1). Most people used that time to party and get drunk, forgetting the symbolic significance of those holidays.

Gorbachev, an impressively progressive and democratic leader for his time, promoted free speech. Criticizing Socialism as a political and economic model became more commonplace. The West was no longer demonized. American pop music, bestselling novels, and blockbuster movies became widely available.

A Child of Dangerous Privilege

An only child of classical musicians, I was considered privileged – by the standards of the time. We belonged to what was called “artistic intelligentsia,” which automatically placed us in some imaginary capsule. In a socialist economy, in which fiscal mobility is severely limited and professors do not get paid significantly more than factory workers, your class was measured not by how much you had but by how much you knew, how many languages you spoke, and how many musical instruments you played.

Respectable professions were not always well compensated, and prestige did not translate into money, yet members of intelligentsia were adamant about setting themselves apart from the rest. I firmly believe that this quest for superiority is one of the fundamental human drives. People will find creative ways to rise above their peers. If they cannot do it through material possessions, they will do it through mannerisms, special skills, and knowledge.

In my novel, Maryana lives in a one-bedroom apartment with her parents and grandmother. An American reader might find such living arrangements horrifying, but by the standards of late Soviet era, this family is considered well off. Having famous parents and a high-achieving engineer grandmother makes the girl privileged.

At the same time, that privilege and her ethnicity make her a delicious target for her less fortunate peers. There were no anti-bullying campaigns, and teachers and school administrators looked the other way. Pedestrian anti-Semitism was widespread, and if a student of Jewish ancestry was assaulted verbally or even physically, the authorities would shrug it off as “Kids will be kids.”

Saved by the Band coverMarina Julia Neary is an award-winning historical essayist, multilingual arts and entertainment journalist, published poet, playwright, actress, dancer, and choreographer. She has written several books set in 19th and 20th century England and Ireland. Her latest release, Saved by the Bang, is available on Amazon.

When a Final Resting Place Is Not a Grave Matter

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Bertrada and Pepin in Basilica of St. Denis

Thirteenth-century effigies depict Charlemagne’s parents, Bertrada and Pepin, at the Basilica of St. Denis. (From Wikimedia Commons, used under the terms of the GNU Free Documentation License, photo by Sailko.)

In my post about Charlemagne and Fastrada for the Lovers theme on Unusual Historicals, I omitted something: where Fastrada is not buried.

What? I hear you ask. Where she’s not buried? Why would that matter?

Well, it doesn’t, but I’ve seen nonfiction authors place meaning in the fact that Charlemagne’s fourth wife is not buried at Basilica of St. Denis near Paris, the resting place of many monarchs, including the king’s parents. Apparently, we should interpret this as a sign that Fastrada was hated and was the cause of rebellions against her husband, as his posthumous biography says.

But this supposition starts to fall apart when we put this in context. Fastrada was interred within a church, the most desired of hallowed ground. In her case, she is at Mainz, near Frankfort, where she died.

When we look at the other two wives Charles loved and outlived, we see a similar pattern. Hildegard, Charles’s third wife, was entombed at Metz, near the relics of St. Arnulf. Charles’s fifth wife, Liutgarda, was buried in Tours, where she and her husband were praying to St. Martin.

Charles himself was not buried at St. Denis. Rather, he was interred in a basilica at Aachen.

Scants written sources, all of them biased, have researchers searching for clues and reading between the lines, but we should take into account which clues are valid.

Sources

“Paul the Deacon’s ‘Gesta Episcoporum Mettensium’ and the Early Design of Charlemagne’s Succession,” Walter Goffart, Traditio

Einhard’s The Life of Charlemagne, translated by Evelyn Scherabon Firchow and Edwin H. Zeydel

Carolingian Chronicles, which includes the Royal Frankish Annals and Nithard’s Histories, translated by Bernhard Walter Scholtz with Barbara Rogers

A History of Charles the Great (Charlemagne), Jacob Isidor Mombert

‘Wonders of the X-ray’

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In this installment of the history of atom theory, physics professor (and my dad) Dean Zollman discusses how x-rays were discovered and later explained. – Kim

By Dean Zollman

Dean ZollmanIn the last decade of the 19th century, many researchers in addition to J.J. Thomson were using cathode ray tubes to conduct research. Before Thomson established that the cathode rays were electrons, several researchers had investigated their properties. Philip Lenard, a German physicist, had measured the range of the “rays” in air. In 1895, Wilhelm Conrad Roentgen was following up on that research by looking at what happened when the cathode rays struck some metals. In the process, he made an astonishing observation.

Wilhelm Conrad Roentgen

Wilhelm Conrad Roentgen by Nobel Foundation

Roentgen had recently moved in the University of Würzburg in southern Germany. He was a professor of physics and had been appointed rector of the university, the equivalent to a president of an American university. However, in those days the university leader had time for research. So, Roentgen had a laboratory where he was studying the properties of cathode rays.

As we discussed last time, the location of cathode rays could be determined because light was emitted when the rays struck a fluorescent material. This process is the same as the way a pre-flat-screen TV creates a picture on it screen. So, Roentgen had some fluorescent material in his lab. A small amount of this material was placed a rather long distance from the cathode ray tube. Yet, Roentgen noticed that the fluorescent material glowed when the tube was operating and the cathode rays were hitting a metal. By this time, cathode rays were known to travel only a few centimeters in air, but the distance between the tube and the glowing material was much greater than that.

Roentgen was motivated to undertake a series of careful experiments. On November 8, 1895, he made sure that no extraneous light could reach the fluorescent material. The lab was dark; the cathode ray tube was covered with black cardboard. Even in this environment Roentgen saw a faint glow on the fluorescent material. Something was traveling through the cardboard and causing light to be emitted from material. Roentgen gave the name x-rays to these new type of radiation.

Early Crookes x-ray tube

An early Crookes x-ray tube from a museum dedicated to Wilhelm Conrad Roentgen in Würzburg, Germany (image used under the terms of GNU Free Documentation License

Why the Professor Didn’t Notice His Dinner

For the next six weeks, Roentgen neglected his students and his duties as university rector to investigate his discovery. (A luxury university administrators do not have today.) He kept his research to himself and talked to very few people about it. The intensity of his work even put some strain on his marriage. This situation was described by a story related on the 35th anniversary of the discovery.

“One of the few persons who knew about the discovery before the announcement was made [on December 28, 1895] was Roentgen’s wife, Bertha. One evening in November 1895, she became very angry with her absent-minded husband because he did not comment upon the excellent dinner she had prepared for him, and he did not even notice that she was angry until she asked him what was the matter. He finally took her downstairs to his laboratory, which was in the same building, and for the first time presented to her astonished eyes the wonders of the x-ray.”

This story, which sounds like it could be an outline for an episode of The Big Bang Theory, is contained in a paper by Otto Glasser and appeared in the American Journal of Roentgenology in 1931. It is verified by a letter which Frau Roentgen wrote to her husband’s cousin.

Bertha Roentgen’s hand

Bertha Roentgen’s hand x-rayed by Wilhelm Roentgen

In his six-week marathon research, Roentgen discovered that x-rays could penetrate materials such as wood, flesh, and a 2,000-page book. However, more dense materials such as metals and bone allowed much less, if any, penetration. He also discovered that photographic plates could be exposed by the x-rays. Three days before Christmas 1895, Roentgen took his wife into his lab and recorded the first (and perhaps most famous) x-ray of part of a person. The bones in Bertha Roentgen’s hand are clearly visible, as is the ring on her hand. Both of the Roentgens’ exposure to x-rays while this picture was being taken must have been tremendous. Today, x-ray machines carefully aim the rays so that only the area of interest is exposed. Over the years, special film and digital detectors have been developed so that only a very small amount of exposure produces the desired result. Roentgen had none of that. He had, at best, a very crude point and shoot x-ray device.

See Your Bones Everywhere, Even in Shoe Shops

On December 28, Roentgen submitted a paper, “Ueber eine neue Art von Strahlung” (On a New Type of Rays) to the Proceedings of the Würzburg Physical-Medical Society. It included the picture of Frau Roentgen’s hand and quickly became a sensation worldwide. The medical implications were immediately recognized, and by May 1896, a handbook Practical Radiography had been published. However, it took a while for the value of x-rays to be fully understood. Tragically, it also took quite a while for the dangers of x-rays to be understood. Many people suffered damage and even death because their exposure to x-rays.

X-raying hands

X-raying hands in the late 19th century (from William J. Morton and Edwin W. Hammer, 1896, The X-ray, or Photography of the Invisible and Its Value in Surgery)

The picture above from an early handbook on using x-rays shows the cavalier ways in which they were treated. Here, two images are being created. The sitting man has his hand on a photographic plate. He will obtain a picture much like the one of Frau Roentgen’s hand. The standing man is holding his hand in front of some fluorescent material. He will be able to see bones move as he changes the position of his hand. The x-rays for both of images are coming from one Crooke’s (cathode ray) tube which is the glass bulb above the sitting man’s hand and in front of the standing man’s hand. X-rays are being emitted in all directions, and neither person has any protection from them. A far cry from your dental hygienist leaving the room when he/she take an x-ray of your tooth (with a machine that focus the x-rays very narrowly on the tooth.)

To show how slowly some of the dangers were addressed, consider buying shoes in the 1950s. When I got new shoes both the salesperson and my parents wanted to be sure that the shoe fit correctly. I, of course, just wanted them to look cool. So, the shoe store had x-ray machines. I would stand on a platform with my feet in this machine. X-rays were directed up from below my feet. There were viewing places with fluorescent material for me, my mother, and the salesperson. We could see how well the shoes fit. Even better, I could wiggle my toes and watch the bones move. So, I had “motivation” to stay in the machine longer than necessary. This “innovation” did not last long, but it did expose us to unnecessary radiation. Maybe that explains why the 1960s were so weird.

So, What Causes X-rays?

Roentgen’s scientific contribution was quickly recognized. The first Nobel prizes were awarded in 1901. The first physics prize went to Wilhelm C. Roentgen “in recognition of the extraordinary services he has rendered by the discovery of the remarkable rays subsequently named after him.” (Roentgen called his discovery x-rays. But in many parts of the world, x-rays are called Roentgen Rays.)

Explanations for what x-rays were and how they were produced took further research. Earlier in the 19th century, James Clerk Maxwell had shown that whenever an electrically charged particle was accelerated, it emitted or absorbed electromagnetic radiation. (For a physicist, acceleration means increasing or decreasing speed or changing direction. The change in direction will haunt us in a few blogs.) To create the x-rays, Roentgen had directed the cathode rays (electrons) into pieces of metal. As the electrically charged electrons slammed into the metal, they slowed and thus lost energy. This energy was emitted as x-rays.

Further research also showed that x-rays had the properties of light. They were much shorter wavelength and higher frequency than visible light. Maxwell had also concluded the light was a form of electromagnetic radiation. So the overall conclusion was that x-rays were the same physical phenomenon as visible light and radio waves. They were much higher energy and thus could pass through some materials that other forms of electromagnetic radiation could not.

Of course, the overall effect of x-rays on society has been much more positive than negative. And eventually they could be explained by models of the atom. In the meantime, other discoveries of the late 19th century were adding to the mystery of the structure of matter. We will look at a really big one – radioactivity – next time.

All images are from Wikimedia Commons. They are in the public domain unless otherwise noted.

Dean Zollman is university distinguished professor of physics at Kansas State University where he has been a faculty member for more than 40 years. During his career he has received four major awards — the American Association of Physics Teachers’ Oersted Medal (2014), the National Science Foundation Director’s Award for Distinguished Teacher Scholars (2004), the Carnegie Foundation for the Advancement of Teaching Doctoral University Professor of the Year (1996), and AAPT’s Robert A. Millikan Medal (1995). His present research concentrates on the teaching and learning of physics and on science teacher preparation.

Previously

What Are Things Made of? Depends on When You Ask.

Ancient Greeks Were the First to Hypothesize Atoms

The Poetry of Atoms

Atom Theory in Ancient India

Religion, Science Clashed over Atoms

Medieval Arabic Scholarship Might Have Preserved Scientific Knowledge

Rediscovering a Roman Poet – and Atom Theory – Centuries Later

Reconciling Atom Theory with Religion

Did Atom Theory Play a Role in Galileo’s Trouble with the Inquisition?

Did Gifted Scientist’s Belief in Atoms Led to His Obscurity?

Does Atom Theory Apply to the Earthly and the Divine?

A Duchess Inspired by Atoms

Separating Atoms from Atheism

Isaac Newton: 300 Years Ahead of His Time

Issac Newton and the Philosopher’s Stone

When Chemistry and Physics Split

Redefining Elements

Mme Lavoisier: Partner in Science, Partner in Life

With Atoms, Proportionality and Simplicity Rule

Despite Evidence of Atoms, 19th Century Skeptics Didn’t Budge

Mission of the First International Scientific Conference: Clear up Confusion

Rivalry over the First Periodic Table

The Puzzle of Dark Lines amid Rainbow Colors

The Colorful Signature of Each Element

Light Waves by the Numbers

Even Scientific Dead Ends Can Contribute to Knowledge

Discovery of the Electron Took Decades and Multiple Scientists

It’s Not Me; It’s My Characters: Why People Get Sick

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Medieval people would look at you askance if you said the reason they were ill was that creatures too tiny to see had invaded their bodies.

Detail from 1910 illustration by Arthur Rackham (public domain, via Wikimedia Commons)

Detail from 1910 illustration by Arthur Rackham (public domain, via Wikimedia Commons)

They knew to stay away from poisonous plants, rotten meat, and polluted water. Christian doctors attributed illness to an imbalance in the humors – blood, yellow bile, black bile, and phlegm. Beyond that, medieval folk turned to the supernatural for explanation.

And here is where Christian Franks and Continental Saxon pagans would argue.

To Christians, the cause for illness could be sorcery or punishment from God. A Saxon pagan might blame an evil, capricious dwarf. At least, I think the pagan would blame a dwarf, based on an Anglo-Saxon charm. So little is known about the Continental Saxons’ beliefs, I had to look for clues in other Germanic religions.

The tension over why people get sick comes into play in The Ashes of Heaven’s Pillar. My heroine, Leova, a Saxon peasant sold into slavery, accepts baptism, but she still holds on to many of her pagan beliefs, as you will see in the excerpt.

Sharing a pallet with Sunwynn, Leova caressed her sleeping daughter’s hair. Three weeks ago, the dwarves had sent fits of coughing throughout the house, and Leova had sung a charm to protect Deorlaf and Sunwynn. The dwarves’ magic had cracked the charm the way a spear cracked a shield. Leova and her children had coughing and a slight fever but were well after a few days.

But the charm had not worked for Ragenard. What did I do wrong? She had chanted the spell first in the left ear, then the right, then above the head. In the light of the night candle and glowing embers of the hearth, Leova stared at the bed, where Ragenard rested. Helewidis was kneeling on the floor, repeatedly murmuring, “Ave Maria, gratia plena.”

But Ragenard, a Christian Frank, has a different explanation for why he was sick for months and what he must do when he has recovered.

“I almost died this spring. The Lord punished me for my sins but spared my life so I could atone.” Ragenard leaned forward and pressed his fingers to his forehead. “I cannot live with you as brother and sister. It is torture to see you every day and not touch you.”

Leova gasped and smiled. He desired her! He cared for her! “So marry me. Then our lying together won’t be a sin. You said so.”

“I am supposed to do penance, not ignore my sins and enjoy pleasures of the flesh.”

Leova’s jaw dropped. “Are you saying you cannot marry me because we would be happy? Why would the Church frown on your happiness with your wife?”

“All I know is that God healed me of this illness years ago, but He let me become sick again after I lay with you.”

Today, we would call Ragenard’s illness tuberculosis. Before antibiotics, this bacterial disease could go into remission for years but come back suddenly. Yes, those invasive creatures too small to be seen made him sick, and he didn’t know it.

When There Might Be More to a Martyrdom Story

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Sometimes I am intrigued by what a story doesn’t say. Such is the case of the martyrdom of Saints Ewald the Fair and Ewald the Black in seventh-century Saxony.

It would be easy to see the pagan Saxon killers as my Frankish characters do – that they were nothing more than a bunch of brutes who hated Christians. Don’t get me wrong: nothing justifies the murder of the two priests. But when we put the story into the context of history and what the Saxons might have believed, it becomes more complex.

The story says the Saxons were convinced the Ewalds were trying to convert their lord and they feared the destruction of their temples. Such an act could offend the gods, the very beings who decided whether you had a bountiful harvest or famine, whether you had victory or defeat in battle.

To the pagan Saxons, the Ewalds might not have been two oddball priests but threats to their community. For more, see my post in English Historical Fiction Authors.

Martydom of Saints Ewald the Fair and Ewald the Black

Stained glass window depicting the martydom of Saints Ewald the Fair and Ewald the Black (photo by Raymakers, public domain image, via Wikimedia Commons)

It’s Not Me, It’s My Characters: Human Sacrifice

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At the beginning of The Ashes of Heaven’s Pillar, Leova, the heroine, belongs to a religion that practices human sacrifice. And that troubles me as a novelist.

I find such a thing revolting. Perhaps, I should’ve taken the easy way out and argued that we have no way of knowing for certain if the Continental Saxons killed people as part of their worship.

Just one problem. After my research, I get the sinking feeling they did sacrifice humans in extreme circumstances such as war or famine, and I owe it to the readers to be true to the characters, faults and all.

So Leova accepts human sacrifice as a way to call on the war god to save her community, as you can see in this excerpt:

Leova swallowed her tears and held her burden more tightly as she and Sunwynn stepped into the hot, dusty chaos of the road. Surrounded by screams and wails, Leova looked to her left and gazed down at the Irminsul, standing tall near the drought-shrunken Diemel River. As long as the oaken pillar stood with its treasure, the gods would favor the Saxon peoples. Leova made out the warriors kneeling before the Irminsul, vowing to sacrifice the first captives and booty they won in battle. Her gaze traveled up the pillar’s great length to the top, where it divided itself into two bent branches and the idol of Wodan stood.

For more about why the Continental Saxons’ religion might have included human sacrifice, see my post on Unusual Historicals.

Irminsul

By Marianne Klement-Speckner (public domain, via Wikimedia Commons)

Pretzels in the Dark Ages?

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Might an early medieval missionary have used pretzels as treats for children? Maybe.

The fifth century Codex 3867 in the Vatican Library has an illustration of something like a pretzel, whose twists resemble arms crossed across the chest, like someone in prayer. Although the first known use of pretzel dates to the 19th century, the word is derived from the German Brezel, which come from the Latin brachiatus, meaning having branches like arms.

A 12th century illustration of Esther and Ahashuerus at a banquet, with a pretzel (public domain, via Wikimedia Commons).

Because pretzels required only flour, water, and salt, they kept well, long enough for a missionary or a conquering army to take to a far-away land. Travel in those days was slow, 12 to 15 miles a day. That is, if no one broke a wheel, got sick, had to deal with ill or injured animals, or was attacked by bandits.

The pretzels’ shape gave them special significance during Lent, when the faithful abstained from meat, dairy, and eggs. Pretzels were among the acceptable foods and probably among the few available as peasants’ food stores dwindled in the early spring.

With this possibility, I used something like a pretzel in The Ashes of Heaven’s Pillar. Even though the events at the beginning of the book occur in the height of summer, it isn’t too much of a stretch to imagine missionaries would want to build a rapport with the youngest of their converts and remind them to pray, as you will see in this excerpt.

When prayers ended, one of the guards approached Leova and gestured for her to hold out her hands. Leova did so stiffly. The guard plucked at the bonds on Leova’s swollen, chafed wrists. Then he knelt by Leova’s feet as if he were going to untie the rope at her ankles. Instead, his hand slid under her skirt and up her calf.

Leova flushed. Oh, how she longed to kick him in the teeth, but it would only make matters worse. She drew in a sharp breath. If Deorlaf saw this, he would rush to defend her honor, just as his father would, and try to fight the guard. A vision of Deorlaf beaten and stabbed flashed before her. She glanced at her son standing a few paces away. A smiling Saxon priest from Britain bent over him and Sunwynn. Holding small strangely twisted rolls, he was telling them about a story about Jesus and children.

She had little time while her children were distracted. Gritting her teeth against the ache in her legs, she stepped back. “Stop this nonsense before Count Pinabel sees you,” she hissed. Although she doubted the guard understood her, she hoped invoking Pinabel’s name would stop him.

Sources

foodtimeline.org

Merriam-Webster

Pretzels for God

Discovery of the Electron Took Decades and Multiple Scientists

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In this installment on the history of atom theory, physics professor (and my dad) Dean Zollman discusses the discovery of the electron. Although one gifted scientist got the credit, he had help. – Kim

By Dean Zollman
Dean ZollmanIn the last decade of the 19th century, discoveries began new directions in our thinking about the composition of matter. Two of these discoveries – radioactivity and x-rays – were somewhat accidental. We will look at each of them in future posts. Another — the identification of the electron as a component of matter – was the result of careful research and the development of improved technologies. In this post, I will discuss the electron, how it was discovered, and some of the recent views about whether this research was really a discovery.

The generally accepted year for the “discovery” of the electron is 1897. However, this discovery had its roots in research and development that date to the first half of the 19th century. Because research such as this is always built on previous work, I have a difficult time knowing how far back to go. I have chosen to start the story with Heinrich Geissler (1814-1879).

Geissler was an instrument maker who, in 1857, created electric discharge tubes. These tubes were long, sealed glass cylinders and had metal electrodes at each end. Geissler connected a high voltage across the two electrodes and used another of his inventions, the vacuum pump, to decrease the pressure inside the tube. He found that the gas inside the tube would glow, with the color depending on what gas was trapped inside. The picture below shows a drawing, published in 1869, of several different Geissler tubes. These instruments might remind you of neon lights and they should. The tubes used in neon lights are modern variations on Geissler tubes.

By M. Rapine (public domain)

Geissler conducted research to improve the tubes. He provided many tubes to other researchers and sold them to nonscientists for entertainment and decorative purposes.

The Cathode Ray

Sir William Crookes as drawn by Sir Leslie Ward in 1902 (public domain)

One of the researchers was William Crookes (1832-1919). Crookes improved on the tube and conducted many experiments. One of his conclusions was that something was being emitted from the negative electrode and was moving in a straight line to the positive end of the tube. Whatever was moving seemed to behave somewhat like rays of light. The negative end of an electrical device was called the cathode, so these “things” became known as cathode rays and the vessels were called cathode-ray tubes. (If you wish to see several photographs of Geissler and Crookes tubes, you should visit the Cathode Ray Tube Site.)

Just like light, the cathode rays could cast a shadow. In a famous experiment. Crookes inserted a Maltese cross in a tube. He saw that a shadow of the cross was cast on the end of the tube. However, the cathode rays in some ways acted differently from light. For example, they could be deflected by a magnetic field.

Maltese cross

By D-Kuru, used under the terms of Creative Commons BY-SA 2.0 license

Two different views of cathode rays developed. Most British physicists concluded that the experiments indicated that the “rays” were some type of particle. Crookes proposed that they were negatively charged molecules. On the European continent, primarily in Germany, the light-like behavior led physicists to the conclusion that the rays were disturbances in the ether.

Each side had some experimental evidence to support its view. At the time, light was “known” to be a wave that traversed the ether, and all waves and other disturbances in the ether were assumed to travel at the same speed as light. However, cathode rays moved at much slower speeds. So this fact was an indication that the rays were not disturbances in the ether but particles. Also, on the particle side, the rays were deflected by a magnetic field, indicating that they had an electrical charge.

Atoms Have ‘Corpuscles’

Many of the prominent scientists who were involved in this debate also conducted work related to the model of the atom as a vortex in the ether that we discussed last month. One was John Joseph Thomson (1856-1940). Last month, I mentioned that he had written a theoretical paper on vortices in the ether. In 1884, he became the Cavendish Professor of Physics at Cambridge University where he undertook many experimental studies. In 1895, x-rays were discovered to be coming from a Crookes tube (more on that discovery next time). This result piqued Thomson’s interest in cathode rays. He set about to measure the ratio of the mass of a cathode ray to its electrical charge. A drawing and a picture of his apparatus are shown below.

Drawing of Thomson's apparatus

By J.J. Thomson (Philosophical Magazine, 44, 293 (1897, Public domain)

 

Photo of Thomson's apparatus

Photo by Science Museum London/ Science and Society Picture Library (used under the terms of Creative Commons BY-SA 2 license)

In the drawing the cathode is labeled C. That is where the cathode rays are emitted. The item marked A is the positive electrode (anode) so the cathode rays are attracted toward it. But there is a slit in the anode, so some of the cathode rays go through the slit and continue their journey. Object B narrows the beam of rays that pass into the next region. D and E are metal plates that can be connected to a battery. Not shown in the drawing but visible in the picture are two coils of wire that can be used to create a magnetic field. With all of this equipment Thomson and his assistants could deflect the cathode rays up or down. Connect the positive side of the battery to D and negative to E and the rays move up. Reverse it and they move down. The magnetic field is a little more complex, but up and down motion can be created by the direction of the electrical current in the coils.

Thomson’s plan was to balance the electrical and magnetic forces so that the cathode rays went straight through his apparatus even though they were subject to both electric and magnetic forces. From voltages and currents, he could determine the magnitude of these forces. Then, doing some algebra with equations that had been developed during the 19th century he could come up with a value for the ratio of the mass of a cathode ray to its charge. He could not determine either the charge by itself or the mass by itself. His measurements allowed only a determination of the ratio.

However, that ratio was enough to indicate that cathode rays were something quite different from any known object. First, they were particles. A disturbance in the ether could not have been deflected in this way. Second, the ratio that Thomson measured was about 1,000 times different than he would have expected if cathode rays were atoms. However, he could not with the experiment determine which was different. The mass could have been 1,000 times smaller or the electric charge could have been 1,000 times bigger. (Thomson measurements were not all that good. Today we know the electron is about 1,800 times less massive than the hydrogen nucleus. But nothing anywhere close to this small had ever been measured, so being off by a large amount did not matter.)

Thomson bet on the mass being smaller. On April 30, 1897, at a public lecture he announced the discovery of “corpuscles,” which he said were very small constituents of all atoms. Over the next few years, he completed several other experiments, including one that enabled him to determine the mass of the corpuscles. Eventually, he built a model of the atom which included the corpuscles. But, I will save that for a later post.

In an earlier post, I mentioned George Stoney (1826 –1911) who coined the word electron in 1891. Others began to use that label for the cathode ray corpuscles, but Thomson did not. In his Nobel Prize acceptance speech (1906), Thomson referred to “carriers of negative electricity” as “corpuscles.” Eventually however, “electron” became the commonly accepted name.

So, Who Deserves the Credit?

Historians and philosophers of science have lots of discussion about the discovery of the electron. Lots of experiments led up to Thomson’s. And others were doing similar experiments at about the same time. So, should Thomson deserve credit for the “discovery” when it was just one step in a many-step process? Further the impact of Thomson’s announcement was not immediate. It took a while to soak in.

Some philosophers will use this example to debate what it means to discover something new. I don’t want to go there. Clearly Thomson’s work was an important step in our understanding of the structure of matter. It built on other people’s work, and others built on it. Some people were doing similar work at the same time. That’s the way science happens.

Next time we will look at something which was clearly a discovery – x-rays.

Post Scripts

  • In addition to being an excellent scientist, Thomson was also a gifted mentor. Seven of his research assistants and his son received Noble Prizes.
  • The cathode-ray tube may seem like an esoteric device. However, until very recently almost all of us had at least one in our homes. Before flat screen televisions, the picture tube on our TVs was an advanced version of a cathode-ray tube. At the back was a device that accelerated electrons. It was quite similar to parts A and C in Thomson’s diagram. Then magnetic coils similar to the coils of wire in Thomson’s apparatus applied forces to steer the electrons to various locations on the front of the screen. Of course, doing this is such a way that we saw a picture required some technology that was not available until the 20th century. But the basic principles are much the same as they were when J.J. Thomson identified cathode rays as corpuscles that eventually came to be called electrons.
  • You can try a virtual version of Thomson’s experiment. This one shows a drawing of modern equipment such as students would use today. In this simulation, changing the current changes the magnetic force while changing the voltage changes the electric force. Another has the same experiment, but it is set in apparatus similar to that of Thomson. For this one, E is the electric field, and B is the magnetic field.

Images via Wikimedia Commons.

Dean Zollman is university distinguished professor of physics at Kansas State University where he has been a faculty member for more than 40 years. During his career he has received four major awards — the American Association of Physics Teachers’ Oersted Medal (2014), the National Science Foundation Director’s Award for Distinguished Teacher Scholars (2004), the Carnegie Foundation for the Advancement of Teaching Doctoral University Professor of the Year (1996), and AAPT’s Robert A. Millikan Medal (1995). His present research concentrates on the teaching and learning of physics and on science teacher preparation.

Previously

What Are Things Made of? Depends on When You Ask.

Ancient Greeks Were the First to Hypothesize Atoms

The Poetry of Atoms

Atom Theory in Ancient India

Religion, Science Clashed over Atoms

Medieval Arabic Scholarship Might Have Preserved Scientific Knowledge

Rediscovering a Roman Poet – and Atom Theory – Centuries Later

Reconciling Atom Theory with Religion

Did Atom Theory Play a Role in Galileo’s Trouble with the Inquisition?

Did Gifted Scientist’s Belief in Atoms Led to His Obscurity?

Does Atom Theory Apply to the Earthly and the Divine?

A Duchess Inspired by Atoms

Separating Atoms from Atheism

Isaac Newton: 300 Years Ahead of His Time

Issac Newton and the Philosopher’s Stone

When Chemistry and Physics Split

Redefining Elements

Mme Lavoisier: Partner in Science, Partner in Life

With Atoms, Proportionality and Simplicity Rule

Despite Evidence of Atoms, 19th Century Skeptics Didn’t Budge

Mission of the First International Scientific Conference: Clear up Confusion

Rivalry over the First Periodic Table

The Puzzle of Dark Lines amid Rainbow Colors

The Colorful Signature of Each Element

Light Waves by the Numbers

Even Scientific Dead Ends Can Contribute to Knowledge

 

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