There are multiple contenders when it comes to the question of who invented the traffic light. This episode looks at a few of the moments in traffic light history that got us to where we are today, as well as what made them a necessity in the first place. 

 Learn more about your ad-choices at https://www.iheartpodcastnetwork.com

There are multiple contenders when it comes to the question of who invented the traffic light. This episode looks at a few of the moments in traffic light history that got us to where we are today, as well as what made them a necessity in the first place.  Learn more about your ad-choices at <a href="https://www.iheartpodcastnetwork.com">https://www.iheartpodcastnetwork.com</a>

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

The Rise of the Traffic Light

https://api.omny.fm/orgs/e73c998e-6e60-432f-8610-ae210140c5b1/clips/9642b643-700c-41cd-aff9-ae28003c0821/transcript

The second part of Percy Fawcett's story delves into his fascination with a document known as Manuscript 512 and how it impacted his life. His obsession led to his disappearance; there has been endless speculation about what exactly happened.

Research:
Biello, David. “Ancient Amazon Actually Highly Urbanized.” Scientific American. August 28, 2008.
“The Brazilian Indigenous People.” Survival International. https://www.survivalinternational.org/peoples/brazilian
Britannica Editors. "Mato Grosso". Encyclopedia Britannica, 10 Jan. 2026, https://www.britannica.com/place/Mato-Grosso
Canal-Soler, Jordi. “The man who died searching for the Lost City of Z.” National geographic. June 13, 2024. https://www.nationalgeographic.com/history/article/percy-fawcett-search-lost-city-of-z
Fawcett, Lt-Col P.H. “Exploration Fawcett.” Hutchinson & Co. London. 1953.
“Fawcett’s Bones Believed Found; Explorer Lost in Brazil Jungle in ’25.” New York Times. April 4, 1951. https://timesmachine.nytimes.com/timesmachine/1951/04/04/82103136.pdf?pdf_redirect=true&ip=0
“Fawcett Mystery Unsolved.” New York Times. Nov. 5, 1951. https://timesmachine.nytimes.com/timesmachine/1951/11/05/81775504.pdf?pdf_redirect=true&ip=0
Grann, David. “The Lost City of Z: A Tale of Deadly Obsession in the Amazon.” Doubleday. 2009.
“Hidden City Is the Goal.” Los Angeles Times. Jan 12, 1925. https://www.newspapers.com/image/380427463/
Hutchison, Percy. “Hunting for Lost Explorers in the Jungles of Brazil.” New York Times. Jan. 26, 1930. https://timesmachine.nytimes.com/timesmachine/1930/01/26/96041140.pdf?pdf_redirect=true&ip=0
Moutinho, Sofia. “A Foundation of Trust.” Science. Nov. 6, 2025. https://www.science.org/content/article/unearth-their-past-amazonian-people-turn-language-white-men-understand
“'Lost' report exposes Brazilian Indian genocide.” Survival International. April 25, 2013. https://www.survivalinternational.org/news/9191
“On Colonel Fawcett’s Train in Unknown Brazil by Air and River.” Illustrated London News. Sep 10, 1932. https://www.newspapers.com/image/1143308620/?match=2&terms=%22Vincenzo%20Petrullo%22&search-id=72603589-1171-4291-b93b-9c5eeffb7d90&search-rank=1
“Percy Fawcett.” Spike Island. https://www.spikeislandcork.ie/percy-fawcett/
“Lieutenant Colonel Percy Harrison Fawcett DSO, (MiD).” Tiegnmouth & Shaldon Remembers WW1. Teign Heritage. https://www.teignheritageworldwar.org.uk/index.php/lieutenant-colonel-percy-harrison-fawcett
Pezzati, Alessandro. "The Lost Explorer." Expedition Magazine59, no. 2. September, 2017. https://www.penn.museum/sites/expedition/the-lost-explorer/
Potts, Mary Anne. “Finding Machu Picchu: A Look at Explorer Hiram Bingham, A Real-Life Indiana Jones.” National Geographic. May 26, 2010. https://www.nationalgeographic.com/adventure/article/machu-picchu-hiram-bingham
“Remembering Col. Fawcett in WWI.” Torquay Museum. Nov. 4, 2021. https://torquaymuseum.org/news/view/remembering-col-fawcett-in-wwi
Ribeiro, Taisa Alves and André Luiz Alves Moreno. “Towards an Archaeology of the Written Culture of Chapada Diamantina-BA: The Case of Manuscript 512.” Garimpus: Journal of Languages, Education and Culture in Chapada Diamantina. Vol. 2, no. 1. 2021. https://www.revistas.uneb.br/garimpus/article/view/8740
“Son of Lost Explorer Says Bones Are Not Fawcett's.” New York Times. Nov. 4, 1951. https://timesmachine.nytimes.com/timesmachine/1951/11/04/96221387.html?pageNumber=66
Squires, Cole. “TRANSCRIPTION/TRANSLATION NOTES (Manuscript 512).” Harvard. https://people.math.harvard.edu/~knill/teaching/mathe320_2021/exhibits/manuscript512/translation.pdf
“Sustainable Mato Grosso.” Amazon Fund. https://www.amazonfund.gov.br/en/projeto/Sustainable-Mato-Grosso/
“Swindon Woman Awaits News of Colonel Fawcett.” Swindon Advertiser. April 13, 1932. https://www.newspapers.com/image/1209686028/?match=2&terms=%22percy%20fawcett%22&search-id=667a33c0-fac9-457e-bcf9-349a1d9b7e9f&search-rank=2
“Why do they hide?” Survival International. https://www.survivalinternational.org/articles/3104-why-do-they-hide

 

The second part of Percy Fawcett's story delves into his fascination with a document known as Manuscript 512 and how it impacted his life. His obsession led to his disappearance; there has been endless speculation about what exactly happened.
Research:
<ul>
<li>Biello, David. &ldquo;Ancient Amazon Actually Highly Urbanized.&rdquo; Scientific American. August 28, 2008.</li>
<li>&ldquo;The Brazilian Indigenous People.&rdquo; Survival International. https://www.survivalinternational.org/peoples/brazilian</li>
<li>Britannica Editors. "Mato Grosso".&nbsp;Encyclopedia Britannica, 10 Jan. 2026, https://www.britannica.com/place/Mato-Grosso</li>
<li>Canal-Soler, Jordi. &ldquo;The man who died searching for the Lost City of Z.&rdquo; National geographic. June 13, 2024. https://www.nationalgeographic.com/history/article/percy-fawcett-search-lost-city-of-z</li>
<li>Fawcett, Lt-Col P.H. &ldquo;Exploration Fawcett.&rdquo; Hutchinson &amp; Co. London. 1953.</li>
<li>&ldquo;Fawcett&rsquo;s Bones Believed Found; Explorer Lost in Brazil Jungle in &rsquo;25.&rdquo; New York Times. April 4, 1951. https://timesmachine.nytimes.com/timesmachine/1951/04/04/82103136.pdf?pdf_redirect=true&amp;ip=0</li>
<li>&ldquo;Fawcett Mystery Unsolved.&rdquo; New York Times. Nov. 5, 1951. https://timesmachine.nytimes.com/timesmachine/1951/11/05/81775504.pdf?pdf_redirect=true&amp;ip=0</li>
<li>Grann, David. &ldquo;The Lost City of Z: A Tale of Deadly Obsession in the Amazon.&rdquo; Doubleday. 2009.</li>
<li>&ldquo;Hidden City Is the Goal.&rdquo; Los Angeles Times. Jan 12, 1925. https://www.newspapers.com/image/380427463/</li>
<li>Hutchison, Percy. &ldquo;Hunting for Lost Explorers in the Jungles of Brazil.&rdquo; New York Times. Jan. 26, 1930. https://timesmachine.nytimes.com/timesmachine/1930/01/26/96041140.pdf?pdf_redirect=true&amp;ip=0</li>
<li>Moutinho, Sofia. &ldquo;A Foundation of Trust.&rdquo; Science. Nov. 6, 2025. https://www.science.org/content/article/unearth-their-past-amazonian-people-turn-language-white-men-understand</li>
<li>&ldquo;'Lost' report exposes Brazilian Indian genocide.&rdquo; Survival International. April 25, 2013. https://www.survivalinternational.org/news/9191</li>
<li>&ldquo;On Colonel Fawcett&rsquo;s Train in Unknown Brazil by Air and River.&rdquo; Illustrated London News. Sep 10, 1932. https://www.newspapers.com/image/1143308620/?match=2&amp;terms=%22Vincenzo%20Petrullo%22&amp;search-id=72603589-1171-4291-b93b-9c5eeffb7d90&amp;search-rank=1</li>
<li>&ldquo;Percy Fawcett.&rdquo; Spike Island. https://www.spikeislandcork.ie/percy-fawcett/</li>
<li>&ldquo;Lieutenant Colonel Percy Harrison Fawcett DSO, (MiD).&rdquo; Tiegnmouth &amp; Shaldon Remembers WW1. Teign Heritage. https://www.teignheritageworldwar.org.uk/index.php/lieutenant-colonel-percy-harrison-fawcett</li>
<li>Pezzati, Alessandro. "The Lost Explorer."&nbsp;Expedition Magazine59, no. 2. September, 2017. https://www.penn.museum/sites/expedition/the-lost-explorer/</li>
<li>Potts, Mary Anne. &ldquo;Finding Machu Picchu: A Look at Explorer Hiram Bingham, A Real-Life Indiana Jones.&rdquo; National Geographic. May 26, 2010. https://www.nationalgeographic.com/adventure/article/machu-picchu-hiram-bingham</li>
<li>&ldquo;Remembering Col. Fawcett in WWI.&rdquo; Torquay Museum. Nov. 4, 2021. https://torquaymuseum.org/news/view/remembering-col-fawcett-in-wwi</li>
<li>Ribeiro, Taisa Alves and Andr&eacute; Luiz Alves Moreno. &ldquo;Towards an Archaeology of the Written Culture of Chapada Diamantina-BA: The Case of Manuscript 512.&rdquo; Garimpus: Journal of Languages, Education and Culture in Chapada Diamantina. Vol. 2, no. 1. 2021. https://www.revistas.uneb.br/garimpus/article/view/8740</li>
<li>&ldquo;Son of Lost Explorer Says Bones Are Not Fawcett's.&rdquo; New York Times. Nov. 4, 1951. https://timesmachine.nytimes.com/timesmachine/1951/11/04/96221387.html?pageNumber=66</li>
<li>Squires, Cole. &ldquo;TRANSCRIPTION/TRANSLATION NOTES (Manuscript 512).&rdquo; Harvard. https://people.math.harvard.edu/~knill/teaching/mathe320_2021/exhibits/manuscript512/translation.pdf</li>
<li>&ldquo;Sustainable Mato Grosso.&rdquo; Amazon Fund. https://www.amazonfund.gov.br/en/projeto/Sustainable-Mato-Grosso/</li>
<li>&ldquo;Swindon Woman Awaits News of Colonel Fawcett.&rdquo; Swindon Advertiser. April 13, 1932. https://www.newspapers.com/image/1209686028/?match=2&amp;terms=%22percy%20fawcett%22&amp;search-id=667a33c0-fac9-457e-bcf9-349a1d9b7e9f&amp;search-rank=2</li>
<li>&ldquo;Why do they hide?&rdquo; Survival International. https://www.survivalinternational.org/articles/3104-why-do-they-hide</li>
</ul>
&nbsp;

The second part of Percy Fawcett's story delves into his fascination with a document known as Manuscript 512 and how it impacted his life. His obsession led to his disappearance; there has been endless speculation about what exactly happened.

Percy Fawcett, Manuscript 512, and a Lost City in the Amazon, Pt. 2

https://api.omny.fm/orgs/e73c998e-6e60-432f-8610-ae210140c5b1/clips/69124264-7025-40c5-a8b0-b4b70046ef49/transcript

Fawcett’s life has invited controversy and speculation, because he was a man who did a mix of great and shady things. Part one covers his early life, marriage, military service, and early visits to South America.

Research:
Biello, David. “Ancient Amazon Actually Highly Urbanized.” Scientific American. August 28, 2008.
“The Brazilian Indigenous People.” Survival International. https://www.survivalinternational.org/peoples/brazilian
Britannica Editors. "Mato Grosso". Encyclopedia Britannica, 10 Jan. 2026, https://www.britannica.com/place/Mato-Grosso
Canal-Soler, Jordi. “The man who died searching for the Lost City of Z.” National geographic. June 13, 2024. https://www.nationalgeographic.com/history/article/percy-fawcett-search-lost-city-of-z
Fawcett, Lt-Col P.H. “Exploration Fawcett.” Hutchinson & Co. London. 1953.
“Fawcett’s Bones Believed Found; Explorer Lost in Brazil Jungle in ’25.” New York Times. April 4, 1951. https://timesmachine.nytimes.com/timesmachine/1951/04/04/82103136.pdf?pdf_redirect=true&ip=0
“Fawcett Mystery Unsolved.” New York Times. Nov. 5, 1951. https://timesmachine.nytimes.com/timesmachine/1951/11/05/81775504.pdf?pdf_redirect=true&ip=0
Grann, David. “The Lost City of Z: A Tale of Deadly Obsession in the Amazon.” Doubleday. 2009.
“Hidden City Is the Goal.” Los Angeles Times. Jan 12, 1925. https://www.newspapers.com/image/380427463/
Hutchison, Percy. “Hunting for Lost Explorers in the Jungles of Brazil.” New York Times. Jan. 26, 1930. https://timesmachine.nytimes.com/timesmachine/1930/01/26/96041140.pdf?pdf_redirect=true&ip=0
Moutinho, Sofia. “A Foundation of Trust.” Science. Nov. 6, 2025. https://www.science.org/content/article/unearth-their-past-amazonian-people-turn-language-white-men-understand
“'Lost' report exposes Brazilian Indian genocide.” Survival International. April 25, 2013. https://www.survivalinternational.org/news/9191
“On Colonel Fawcett’s Train in Unknown Brazil by Air and River.” Illustrated London News. Sep 10, 1932. https://www.newspapers.com/image/1143308620/?match=2&terms=%22Vincenzo%20Petrullo%22&search-id=72603589-1171-4291-b93b-9c5eeffb7d90&search-rank=1
“Percy Fawcett.” Spike Island. https://www.spikeislandcork.ie/percy-fawcett/
“Lieutenant Colonel Percy Harrison Fawcett DSO, (MiD).” Tiegnmouth & Shaldon Remembers WW1. Teign Heritage. https://www.teignheritageworldwar.org.uk/index.php/lieutenant-colonel-percy-harrison-fawcett
Pezzati, Alessandro. "The Lost Explorer." Expedition Magazine59, no. 2. September, 2017. https://www.penn.museum/sites/expedition/the-lost-explorer/
Potts, Mary Anne. “Finding Machu Picchu: A Look at Explorer Hiram Bingham, A Real-Life Indiana Jones.” National Geographic. May 26, 2010. https://www.nationalgeographic.com/adventure/article/machu-picchu-hiram-bingham
“Remembering Col. Fawcett in WWI.” Torquay Museum. Nov. 4, 2021. https://torquaymuseum.org/news/view/remembering-col-fawcett-in-wwi
Ribeiro, Taisa Alves and André Luiz Alves Moreno. “Towards an Archaeology of the Written Culture of Chapada Diamantina-BA: The Case of Manuscript 512.” Garimpus: Journal of Languages, Education and Culture in Chapada Diamantina. Vol. 2, no. 1. 2021. https://www.revistas.uneb.br/garimpus/article/view/8740
“Son of Lost Explorer Says Bones Are Not Fawcett's.” New York Times. Nov. 4, 1951. https://timesmachine.nytimes.com/timesmachine/1951/11/04/96221387.html?pageNumber=66
Squires, Cole. “TRANSCRIPTION/TRANSLATION NOTES (Manuscript 512).” Harvard. https://people.math.harvard.edu/~knill/teaching/mathe320_2021/exhibits/manuscript512/translation.pdf
“Sustainable Mato Grosso.” Amazon Fund. https://www.amazonfund.gov.br/en/projeto/Sustainable-Mato-Grosso/
“Swindon Woman Awaits News of Colonel Fawcett.” Swindon Advertiser. April 13, 1932. https://www.newspapers.com/image/1209686028/?match=2&terms=%22percy%20fawcett%22&search-id=667a33c0-fac9-457e-bcf9-349a1d9b7e9f&search-rank=2
“Why do they hide?” Survival International. https://www.survivalinternational.org/articles/3104-why-do-they-hide

 

Fawcett&rsquo;s life has invited controversy and speculation, because he was a man who did a mix of great and shady things. Part one covers his early life, marriage, military service, and early visits to South America.
Research:
<ul>
<li>Biello, David. &ldquo;Ancient Amazon Actually Highly Urbanized.&rdquo; Scientific American. August 28, 2008.</li>
<li>&ldquo;The Brazilian Indigenous People.&rdquo; Survival International. https://www.survivalinternational.org/peoples/brazilian</li>
<li>Britannica Editors. "Mato Grosso".&nbsp;Encyclopedia Britannica, 10 Jan. 2026, https://www.britannica.com/place/Mato-Grosso</li>
<li>Canal-Soler, Jordi. &ldquo;The man who died searching for the Lost City of Z.&rdquo; National geographic. June 13, 2024. https://www.nationalgeographic.com/history/article/percy-fawcett-search-lost-city-of-z</li>
<li>Fawcett, Lt-Col P.H. &ldquo;Exploration Fawcett.&rdquo; Hutchinson &amp; Co. London. 1953.</li>
<li>&ldquo;Fawcett&rsquo;s Bones Believed Found; Explorer Lost in Brazil Jungle in &rsquo;25.&rdquo; New York Times. April 4, 1951. https://timesmachine.nytimes.com/timesmachine/1951/04/04/82103136.pdf?pdf_redirect=true&amp;ip=0</li>
<li>&ldquo;Fawcett Mystery Unsolved.&rdquo; New York Times. Nov. 5, 1951. https://timesmachine.nytimes.com/timesmachine/1951/11/05/81775504.pdf?pdf_redirect=true&amp;ip=0</li>
<li>Grann, David. &ldquo;The Lost City of Z: A Tale of Deadly Obsession in the Amazon.&rdquo; Doubleday. 2009.</li>
<li>&ldquo;Hidden City Is the Goal.&rdquo; Los Angeles Times. Jan 12, 1925. https://www.newspapers.com/image/380427463/</li>
<li>Hutchison, Percy. &ldquo;Hunting for Lost Explorers in the Jungles of Brazil.&rdquo; New York Times. Jan. 26, 1930. https://timesmachine.nytimes.com/timesmachine/1930/01/26/96041140.pdf?pdf_redirect=true&amp;ip=0</li>
<li>Moutinho, Sofia. &ldquo;A Foundation of Trust.&rdquo; Science. Nov. 6, 2025. https://www.science.org/content/article/unearth-their-past-amazonian-people-turn-language-white-men-understand</li>
<li>&ldquo;'Lost' report exposes Brazilian Indian genocide.&rdquo; Survival International. April 25, 2013. https://www.survivalinternational.org/news/9191</li>
<li>&ldquo;On Colonel Fawcett&rsquo;s Train in Unknown Brazil by Air and River.&rdquo; Illustrated London News. Sep 10, 1932. https://www.newspapers.com/image/1143308620/?match=2&amp;terms=%22Vincenzo%20Petrullo%22&amp;search-id=72603589-1171-4291-b93b-9c5eeffb7d90&amp;search-rank=1</li>
<li>&ldquo;Percy Fawcett.&rdquo; Spike Island. https://www.spikeislandcork.ie/percy-fawcett/</li>
<li>&ldquo;Lieutenant Colonel Percy Harrison Fawcett DSO, (MiD).&rdquo; Tiegnmouth &amp; Shaldon Remembers WW1. Teign Heritage. https://www.teignheritageworldwar.org.uk/index.php/lieutenant-colonel-percy-harrison-fawcett</li>
<li>Pezzati, Alessandro. "The Lost Explorer."&nbsp;Expedition Magazine59, no. 2. September, 2017. https://www.penn.museum/sites/expedition/the-lost-explorer/</li>
<li>Potts, Mary Anne. &ldquo;Finding Machu Picchu: A Look at Explorer Hiram Bingham, A Real-Life Indiana Jones.&rdquo; National Geographic. May 26, 2010. https://www.nationalgeographic.com/adventure/article/machu-picchu-hiram-bingham</li>
<li>&ldquo;Remembering Col. Fawcett in WWI.&rdquo; Torquay Museum. Nov. 4, 2021. https://torquaymuseum.org/news/view/remembering-col-fawcett-in-wwi</li>
<li>Ribeiro, Taisa Alves and Andr&eacute; Luiz Alves Moreno. &ldquo;Towards an Archaeology of the Written Culture of Chapada Diamantina-BA: The Case of Manuscript 512.&rdquo; Garimpus: Journal of Languages, Education and Culture in Chapada Diamantina. Vol. 2, no. 1. 2021. https://www.revistas.uneb.br/garimpus/article/view/8740</li>
<li>&ldquo;Son of Lost Explorer Says Bones Are Not Fawcett's.&rdquo; New York Times. Nov. 4, 1951. https://timesmachine.nytimes.com/timesmachine/1951/11/04/96221387.html?pageNumber=66</li>
<li>Squires, Cole. &ldquo;TRANSCRIPTION/TRANSLATION NOTES (Manuscript 512).&rdquo; Harvard. https://people.math.harvard.edu/~knill/teaching/mathe320_2021/exhibits/manuscript512/translation.pdf</li>
<li>&ldquo;Sustainable Mato Grosso.&rdquo; Amazon Fund. https://www.amazonfund.gov.br/en/projeto/Sustainable-Mato-Grosso/</li>
<li>&ldquo;Swindon Woman Awaits News of Colonel Fawcett.&rdquo; Swindon Advertiser. April 13, 1932. https://www.newspapers.com/image/1209686028/?match=2&amp;terms=%22percy%20fawcett%22&amp;search-id=667a33c0-fac9-457e-bcf9-349a1d9b7e9f&amp;search-rank=2</li>
<li>&ldquo;Why do they hide?&rdquo; Survival International. https://www.survivalinternational.org/articles/3104-why-do-they-hide</li>
</ul>
&nbsp;

Fawcett’s life has invited controversy and speculation, because he was a man who did a mix of great and shady things. Part one covers his early life, marriage, military service, and early visits to South America.

Percy Fawcett, Manuscript 512, and a Lost City in the Amazon, Pt. 1

https://api.omny.fm/orgs/e73c998e-6e60-432f-8610-ae210140c5b1/clips/9f2834cd-2294-44b2-a0e7-b4b300fb7953/transcript

This 2021 episode covers a period of time when the milk supply in New York was anything but appetizing and wholesome – it was often deadly. But efforts to address the problem were blocked by corrupt officials.

This 2021 episode covers a period of time when the milk supply in New York was anything but appetizing and wholesome &ndash; it was often deadly. But efforts to address the problem were blocked by corrupt officials.

SYMHC Classics: Swill Milk

https://api.omny.fm/orgs/e73c998e-6e60-432f-8610-ae210140c5b1/clips/4016d6e6-4a83-48e9-9d7f-b4b1015cc0b8/transcript

The Rise of the Traffic Light

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