This 2020 episode covers the sphere of plutonium-gallium alloy that the U.S. made for use in an atomic bomb during World War II known as the Demon Core was  It was the source of two fatal criticality accidents. 

This 2020 episode covers the sphere of plutonium-gallium alloy that the U.S. made for use in an atomic bomb during World War II known as the Demon Core was&nbsp; It was the source of two fatal criticality accidents.&nbsp;

Join Holly and Tracy as they bring you the greatest and strangest Stuff You Missed In History Class in this podcast by iHeartRadio.

Stuff You Missed in History Class

SYMHC Classics: Demon Core

https://api.omny.fm/orgs/e73c998e-6e60-432f-8610-ae210140c5b1/clips/0664e515-08a0-49a9-aa7e-b244013f86e2/transcript

Tracy talks about her selection of "Fumifugium" as a show topic. Holly shares a mischievous story about Helen Preece.

Tracy talks about her selection of "Fumifugium" as a show topic. Holly shares a mischievous story about Helen Preece.

Behind the Scenes Minis: Pollution Olympics

https://api.omny.fm/orgs/e73c998e-6e60-432f-8610-ae210140c5b1/clips/0b70659f-becc-4ab3-bb70-b3e8015b002e/transcript

Despite Pierre de Coubertin's vision of the Olympics being for male athletes only, women did participate in the games starting in 1900. But the road to equal participation was long and filled with disappointments.

Research:
Barker, Philip. “Women’s Sporting Pioneer Milliat Remembered At Paris 2024.” International Society of Olympic Historians. https://isoh.org/womens-sporting-pioneer-milliat-remembered-at-paris-2024/
Branch, John. “They Called It ‘Improper’ to Have Women in the Olympics. But She Persisted.” New York Times. July 11, 2024. https://www.nytimes.com/2024/07/10/olympics-women-milliat.html
Camps Y Wilant, Natalie and George Hirthler. “The rationale behind Coubertin's opposition to women competing in the Olympic Games.” International Olympic Committee. https://www.olympics.com/ioc/pierre-de-coubertin/the-rationale-behind-coubertins-opposition-to-women-competing-in-the-olympic-games
Coubertin, Pierre de, et al., edited by the International Olympic Committee. “Olympism: selected writings / Pierre de Coubertin.” 2000. https://library.olympics.com/Default/doc/SYRACUSE/65192/olympism-selected-writings-pierre-de-coubertin
Gillen, Nancy. “La Vie Jamais Racontée: Alice Milliat, a French Heroine and Sporting Suffragette.” Pitch Publishing. 2024. 
“Girl of 15 Is Only Woman Entrant in Olympic Games.” Democrat and Chrinicle. July 7, 1912. https://www.newspapers.com/image/135686582/?match=1&terms=helen%20preece
Leigh, Mary H., and Thérèse M. Bonin. “The Pioneering Role Of Madame Alice Milliat and the FSFI in Establishing International Trade and Field Competition for Women.” Journal of Sport History, vol. 4, no. 1, 1977, pp. 72–83. JSTOR, http://www.jstor.org/stable/43611530
Lennartz, Karl, and Walter Teutenberg. “THE COUNTESS DE POURTALES - AFTER ALL THE FIRST MODERN FEMALE OLYMPIC STARTER.” International Society of Olympic Historians. https://isoh.org/wp-content/uploads/JOH-Archives/JOHv4n2e.pdf
Lough, Tom, et al. “’A possibility of a lady competitor’: Helen Preece and the 1912 Olympic modern pentathlon.” Journal of Olympic History. 2021. https://library.olympics.com/Default/doc/SYRACUSE/3156581/a-possibility-of-a-lady-competitor-helen-preece-and-the-1912-olympic-modern-pentathlon-by-tom-lough-?_lg=en-GB
McSweeney, Megan. “Women’s History Spotlight: Hélène de Pourtalès.” Sail. March 4, 2022. https://sailmagazine.com/web-exclusives/womens-history-spotlight-helene-de-pourtales/
Mallon, Bill. “The 1900 Olympic Games: Results for All Competitors in All Events, with Commentary. McFarland. 2009.
Married to Instructor at Her School.” St. Louis Post-Dispatch. Dec. 18, 1934. https://www.newspapers.com/image/139260559/?clipping_id=15003174&fcfToken=eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9.eyJmcmVlLXZpZXctaWQiOjEzOTI2MDU1OSwiaWF0IjoxNzY5NDYyNzQ2LCJleHAiOjE3Njk1NDkxNDZ9.Lyc2T8nmqG9SxDg4PVDUDy6zfD_710wD6wKDLrIIC-dt72QRLBeUb8SruN75BdgtucDfcSzfYx8UgqVgqY57vw
“Paris 1900 Olympic Poster.” Qatar Museums. https://collections.qm.org.qa/en/objects/paris-1900-olympic-poster-qosm20136233
“Personalities at the Olympia Horse Show.” The Sphere (London). June 18, 1910. https://www.newspapers.com/image/1149409173/?match=1&terms=%22Helen%20Preece%22
“The Queen and the Girl Rider.” Telegraph and Argus. March 12, 1910. https://www.newspapers.com/image/1219683551/?match=1&terms=%22Helen%20Preece%22
“Sailing at the 1900 Summer Olympics (includes text of A Review of Olympic Yachting – 1900; by Ian Buchanan).” Olympedia. https://www.olympedia.org/editions/2/sports/SAL
“Sues to Have Girl Cease Using Her Name.” The Tampa Times. July 13, 1915. https://www.newspapers.com/image/325742028/?clipping_id=15002352&fcfToken=eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9.eyJmcmVlLXZpZXctaWQiOjMyNTc0MjAyOCwiaWF0IjoxNzY5NDYyNzQxLCJleHAiOjE3Njk1NDkxNDF9.McrNQr7AvEveo5cVIJdb4lYPetsUxCr-RW1Nn7W70PGKwC7FacJsU23KT0eewZT8zHm55Jkblmm-lc7dUKPslw
Vuilleumier, Christophe. “The First Female Olympic Champion.” Swiss National Museum. Dec. 17, 2025. https://blog.nationalmuseum.ch/en/2021/07/the-first-female-olympic-champion/
“Winner of Polo Pony Jumping Competition.” Daily Mirror. March 15, 1909. https://www.newspapers.com/image/789742337/?match=1&terms=%22Helen%20Preece%22

 

Despite Pierre de Coubertin's vision of the Olympics being for male athletes only, women did participate in the games starting in 1900. But the road to equal participation was long and filled with disappointments.
Research:
<ul>
<li>Barker, Philip. &ldquo;Women&rsquo;s Sporting Pioneer Milliat Remembered At Paris 2024.&rdquo; International Society of Olympic Historians. https://isoh.org/womens-sporting-pioneer-milliat-remembered-at-paris-2024/</li>
<li>Branch, John. &ldquo;They Called It &lsquo;Improper&rsquo; to Have Women in the Olympics. But She Persisted.&rdquo; New York Times. July 11, 2024. https://www.nytimes.com/2024/07/10/olympics-women-milliat.html</li>
<li>Camps Y Wilant, Natalie and George Hirthler. &ldquo;The rationale behind Coubertin's opposition to women competing in the Olympic Games.&rdquo; International Olympic Committee. https://www.olympics.com/ioc/pierre-de-coubertin/the-rationale-behind-coubertins-opposition-to-women-competing-in-the-olympic-games</li>
<li>Coubertin, Pierre de, et al., edited by the International Olympic Committee. &ldquo;Olympism: selected writings / Pierre de Coubertin.&rdquo; 2000. https://library.olympics.com/Default/doc/SYRACUSE/65192/olympism-selected-writings-pierre-de-coubertin</li>
<li>Gillen, Nancy. &ldquo;La Vie Jamais Racont&eacute;e: Alice Milliat, a French Heroine and Sporting Suffragette.&rdquo; Pitch Publishing. 2024. </li>
<li>&ldquo;Girl of 15 Is Only Woman Entrant in Olympic Games.&rdquo; Democrat and Chrinicle. July 7, 1912. https://www.newspapers.com/image/135686582/?match=1&amp;terms=helen%20preece</li>
<li>Leigh, Mary H., and Th&eacute;r&egrave;se M. Bonin. &ldquo;The Pioneering Role Of Madame Alice Milliat and the FSFI in Establishing International Trade and Field Competition for Women.&rdquo; Journal of Sport History, vol. 4, no. 1, 1977, pp. 72&ndash;83. JSTOR, http://www.jstor.org/stable/43611530</li>
<li>Lennartz, Karl, and Walter Teutenberg. &ldquo;THE COUNTESS DE POURTALES - AFTER ALL THE FIRST MODERN FEMALE OLYMPIC STARTER.&rdquo; International Society of Olympic Historians. https://isoh.org/wp-content/uploads/JOH-Archives/JOHv4n2e.pdf</li>
<li>Lough, Tom, et al. &ldquo;&rsquo;A possibility of a lady competitor&rsquo;: Helen Preece and the 1912 Olympic modern pentathlon.&rdquo; Journal of Olympic History. 2021. https://library.olympics.com/Default/doc/SYRACUSE/3156581/a-possibility-of-a-lady-competitor-helen-preece-and-the-1912-olympic-modern-pentathlon-by-tom-lough-?_lg=en-GB</li>
<li>McSweeney, Megan. &ldquo;Women&rsquo;s History Spotlight: H&eacute;l&egrave;ne de Pourtal&egrave;s.&rdquo; Sail. March 4, 2022. https://sailmagazine.com/web-exclusives/womens-history-spotlight-helene-de-pourtales/</li>
<li>Mallon, Bill. &ldquo;The 1900 Olympic Games:&nbsp;Results for All Competitors in All Events, with Commentary. McFarland. 2009.</li>
<li>Married to Instructor at Her School.&rdquo; St. Louis Post-Dispatch. Dec. 18, 1934. https://www.newspapers.com/image/139260559/?clipping_id=15003174&amp;fcfToken=eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9.eyJmcmVlLXZpZXctaWQiOjEzOTI2MDU1OSwiaWF0IjoxNzY5NDYyNzQ2LCJleHAiOjE3Njk1NDkxNDZ9.Lyc2T8nmqG9SxDg4PVDUDy6zfD_710wD6wKDLrIIC-dt72QRLBeUb8SruN75BdgtucDfcSzfYx8UgqVgqY57vw</li>
<li>&ldquo;Paris 1900 Olympic Poster.&rdquo; Qatar Museums. https://collections.qm.org.qa/en/objects/paris-1900-olympic-poster-qosm20136233</li>
<li>&ldquo;Personalities at the Olympia Horse Show.&rdquo; The Sphere (London). June 18, 1910. https://www.newspapers.com/image/1149409173/?match=1&amp;terms=%22Helen%20Preece%22</li>
<li>&ldquo;The Queen and the Girl Rider.&rdquo; Telegraph and Argus. March 12, 1910. https://www.newspapers.com/image/1219683551/?match=1&amp;terms=%22Helen%20Preece%22</li>
<li>&ldquo;Sailing at the 1900 Summer Olympics (includes text of A Review of Olympic Yachting &ndash; 1900; by Ian Buchanan).&rdquo; Olympedia. https://www.olympedia.org/editions/2/sports/SAL</li>
<li>&ldquo;Sues to Have Girl Cease Using Her Name.&rdquo; The Tampa Times. July 13, 1915. https://www.newspapers.com/image/325742028/?clipping_id=15002352&amp;fcfToken=eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9.eyJmcmVlLXZpZXctaWQiOjMyNTc0MjAyOCwiaWF0IjoxNzY5NDYyNzQxLCJleHAiOjE3Njk1NDkxNDF9.McrNQr7AvEveo5cVIJdb4lYPetsUxCr-RW1Nn7W70PGKwC7FacJsU23KT0eewZT8zHm55Jkblmm-lc7dUKPslw</li>
<li>Vuilleumier, Christophe. &ldquo;The First Female Olympic Champion.&rdquo; Swiss National Museum. Dec. 17, 2025. https://blog.nationalmuseum.ch/en/2021/07/the-first-female-olympic-champion/</li>
<li>&ldquo;Winner of Polo Pony Jumping Competition.&rdquo; Daily Mirror. March 15, 1909. https://www.newspapers.com/image/789742337/?match=1&amp;terms=%22Helen%20Preece%22</li>
</ul>
&nbsp;

Despite Pierre de Coubertin's vision of the Olympics being for male athletes only, women did participate in the games starting in 1900. But the road to equal participation was long and filled with disappointments.

Notable Early Women Olympians

https://api.omny.fm/orgs/e73c998e-6e60-432f-8610-ae210140c5b1/clips/dbc67a46-bcab-4911-be7c-b3e5001bf034/transcript

"Fumifugium"was a treatise on air pollution written in 1661. In addition to warning about the dangers of coal smoke, John Evelyn wrote this work to improve the reputation of King Charles II.

Research:
Chambers, Douglas D. C. "Evelyn, John (1620–1706), diarist and writer." Oxford Dictionary of National Biography. January 03, 2008. Oxford University Press. Date of access 13 Jan. 2026, https://www.oxforddnb.com/view/10.1093/ref:odnb/9780198614128.001.0001/odnb-9780198614128-e-8996
"Evelyn, John (1620-1706)." Encyclopedia of World Biography, Gale, 1998. Gale Academic OneFile, link.gale.com/apps/doc/A148426050/GPS?u=mlin_n_melpub&sid=bookmark-GPS&xid=ab356add. Accessed 13 Jan. 2026.
Borunda, Alejandra. “The EPA is changing how it considers the costs and benefits of air pollution rules.” NPR. 1/13/2026. https://www.npr.org/2026/01/13/nx-s1-5675307/epa-air-regulations-health-benefits
DeWispelare, Daniel. “’Heavy Fumes of Charcoal Creep into the Brain.’” The 18th-century Common. 5/14/2018. https://www.18thcenturycommon.org/evelyn/
Hovde, Sarah. “A solution for pollution?” Folger Shakespeare Library. 4/21/2017. https://www.folger.edu/blogs/shakespeare-and-beyond/air-pollution-london-fumifugium/
London School of Hygiene and Tropical Medicine. “Pamphlet Collection: Fumifugium, by John Evelyn.” Library, Archive & Open Research Services Blog. 7/11/2022. https://blogs.lshtm.ac.uk/library/2022/11/07/pamphlet-collection-fumifugium-by-john-evelyn/
Jenner, Mark. (1995) The politics of London air : John Evelyn's 'Fumifugium' and the Restoration. The Historical Journal. pp. 535-551. ISSN: 1469-5103. https://eprints.whiterose.ac.uk/id/eprint/1550/1/jennerm1.pdf
Heidorn, K.C. “A Chronology of Important Events in the History of Air Pollution Meteorology to 1970.” Bulletin of the American Meteorological Society, December 1978, Vol. 59, No. 12 (December 1978). Via JSTOR. https://www.jstor.org/stable/26219252
Foster, John Bellamy. “Introduction to John Evelyn’s ‘Fumifugium.’” Organization & Environment, June 1999, Vol. 12, No. 2 (June 1999). https://www.jstor.org/stable/26161864
Brimblecombe, Peter. “Interest in Air Pollution among Early Fellows of the Royal Society.” Notes and Records of the Royal Society of London, Mar., 1978, Vol. 32, No. 2 (Mar., 1978). Via JSTOR. https://www.jstor.org/stable/531723
Cavert, William M. “The Environmental Policy of Charles I: Coal Smoke and the English Monarchy, 1624–40.” Journal of British Studies, APRIL 2014, Vol. 53, No. 2 (APRIL 2014). Via JSTOR. https://www.jstor.org/stable/24701865
Darley, Gillian. “John Evelyn: Britain's First Environmentalist.” Gresham College. 11/12/2020. https://www.youtube.com/watch?v=pOik751LhHk
Surrey Heritage. “John Evelyn (1620 – 1706).” https://www.exploringsurreyspast.org.uk/themes/people/writers/john_evelyn/
Evelyn, John. “Fumifugium.” 1661. https://archive.org/details/fumifugium00eveluoft/

"Fumifugium" was a treatise on air pollution written in 1661. In addition to warning about the dangers of coal smoke, John Evelyn wrote this work to improve the reputation of King Charles II.
Research:
<ul>
<li>Chambers, Douglas D. C. "Evelyn, John (1620&ndash;1706), diarist and writer." Oxford Dictionary of National Biography. January 03, 2008. Oxford University Press. Date of access 13 Jan. 2026, https://www.oxforddnb.com/view/10.1093/ref:odnb/9780198614128.001.0001/odnb-9780198614128-e-8996</li>
<li>"Evelyn, John (1620-1706)." Encyclopedia of World Biography, Gale, 1998. Gale Academic OneFile, link.gale.com/apps/doc/A148426050/GPS?u=mlin_n_melpub&amp;sid=bookmark-GPS&amp;xid=ab356add. Accessed 13 Jan. 2026.</li>
<li>Borunda, Alejandra. &ldquo;The EPA is changing how it considers the costs and benefits of air pollution rules.&rdquo; NPR. 1/13/2026. https://www.npr.org/2026/01/13/nx-s1-5675307/epa-air-regulations-health-benefits</li>
<li>DeWispelare, Daniel. &ldquo;&rsquo;Heavy Fumes of Charcoal Creep into the Brain.&rsquo;&rdquo; The 18th-century Common. 5/14/2018. https://www.18thcenturycommon.org/evelyn/</li>
<li>Hovde, Sarah. &ldquo;A solution for pollution?&rdquo; Folger Shakespeare Library. 4/21/2017. https://www.folger.edu/blogs/shakespeare-and-beyond/air-pollution-london-fumifugium/</li>
<li>London School of Hygiene and Tropical Medicine. &ldquo;Pamphlet Collection: Fumifugium, by John Evelyn.&rdquo; Library, Archive &amp; Open Research Services Blog. 7/11/2022. https://blogs.lshtm.ac.uk/library/2022/11/07/pamphlet-collection-fumifugium-by-john-evelyn/</li>
<li>Jenner, Mark. (1995) The politics of London air : John Evelyn's 'Fumifugium' and the Restoration. The Historical Journal. pp. 535-551. ISSN: 1469-5103. https://eprints.whiterose.ac.uk/id/eprint/1550/1/jennerm1.pdf</li>
<li>Heidorn, K.C. &ldquo;A Chronology of Important Events in the History of Air Pollution Meteorology to 1970.&rdquo; Bulletin of the American Meteorological Society, December 1978, Vol. 59, No. 12 (December 1978). Via JSTOR. https://www.jstor.org/stable/26219252</li>
<li>Foster, John Bellamy. &ldquo;Introduction to John Evelyn&rsquo;s &lsquo;Fumifugium.&rsquo;&rdquo; Organization &amp; Environment, June 1999, Vol. 12, No. 2 (June 1999). https://www.jstor.org/stable/26161864</li>
<li>Brimblecombe, Peter. &ldquo;Interest in Air Pollution among Early Fellows of the Royal Society.&rdquo; Notes and Records of the Royal Society of London, Mar., 1978, Vol. 32, No. 2 (Mar., 1978). Via JSTOR. https://www.jstor.org/stable/531723</li>
<li>Cavert, William M. &ldquo;The Environmental Policy of Charles I: Coal Smoke and the English Monarchy, 1624&ndash;40.&rdquo; Journal of British Studies, APRIL 2014, Vol. 53, No. 2 (APRIL 2014). Via JSTOR. https://www.jstor.org/stable/24701865</li>
<li>Darley, Gillian. &ldquo;John Evelyn: Britain's First Environmentalist.&rdquo; Gresham College. 11/12/2020. https://www.youtube.com/watch?v=pOik751LhHk</li>
<li>Surrey Heritage. &ldquo;John Evelyn (1620 &ndash; 1706).&rdquo; https://www.exploringsurreyspast.org.uk/themes/people/writers/john_evelyn/</li>
<li>Evelyn, John. &ldquo;Fumifugium.&rdquo; 1661. https://archive.org/details/fumifugium00eveluoft/</li>
</ul>

"Fumifugium" was a treatise on air pollution written in 1661. In addition to warning about the dangers of coal smoke, John Evelyn wrote this work to improve the reputation of King Charles II.

John Evelyn's 'Fumifugium'

https://api.omny.fm/orgs/e73c998e-6e60-432f-8610-ae210140c5b1/clips/b4dd01b6-edb0-4808-b4c1-b3e2003e67a9/transcript

SYMHC Classics: Demon Core

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