Brains On! Science podcast for kids · Brains On Universe

How metal wires changed the world!

December 16, 2025·28 min·2 clips

How did stacking zinc and copper sheets with seawater lead to the first electrical currents?

This episode concludes the three-part series on metal, focusing on how metal wires revolutionized global communication. Host Molly Bloom is joined by returning co-host Ava and guide Dylan Thurus, co-founder of Atlas Obscura and co-author of a book on inventions. They explore the historical convergence of wire production and electrical discovery that enabled long-distance messaging. The episode sets the scene in the late 1700s and early 1800s during the Industrial Revolution, powered by steam engines like those in trains and factories. Scientists in the 1700s discovered that stacking zinc and copper sheets separated by an egg soaked in seawater could create an electrical current. People realized electricity could travel as signals through metal wires, which were becoming cheaper and more plentiful due to new manufacturing techniques. The primary communication problem was that sending letters via boat or horse could take weeks or months across long distances. The telegraph was invented to send messages using pulses of electricity translated into Morse code, like using short and long beeps for letters. An initial attempt to lay a trans-oceanic telegraph cable in 1858 failed after a few weeks, likely due to damage on the ocean floor. A successful, stronger cable was laid about ten years later, allowing messages like one from Queen Victoria to President Buchanan to cross the Atlantic. A surprising insight is that metals are compared to Superman, having hidden "superpowers" beyond just being solid materials. The episode reveals that early electrical experiments involved mundane items like eggs and seawater, not complex lab equipment. It emphasizes that major inventions like the telegraph were not single "Eureka" moments but slow, collaborative processes involving many people. The narrative includes a quirky framing story where the characters need "comically large scissors" for a grand opening ceremony at their new headquarters. A mystery sound segment features a puzzling noise that turns out to be an egg rolling in a metal mixing bowl. The tone is educational and conversational, blending historical facts with playful, scripted banter between the host and fictional characters. The style is narrative-driven, using analogies like Clark Kent and a continuous storyline about the headquarters to engage young listeners. Kids curious about history, inventions, and the science behind everyday objects like wires and electricity would love this episode. Listeners who prefer episodes focused solely on natural science or experiments without historical context might skip it.

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