It’s day 4 of our week-long countdown, 25 People Who Changed the World… for Better, for Worse, and for Sillier! Today we visit Mary’s hometown to find out how one self-taught man solved a big log problem, discover an invention that changed the game (well, all the games), and unpack the science inside picnic coolers. Plus: The nurse whose invention was ahead of Ring cameras by decades.

• Learn more about Maine’s logging history at the Maine Forest & Logging Museum and the Maine State Museum.
• Learn about the Gerald A. Lawson Fund, which provides scholarships for Black and Indigenous students at the University of Southern California’s USC Games program.
• Listen to The Builders with Walter Isaacson, available now wherever you get podcasts.
• Subscribe to Mango’s newsletter!

Did you hear? PTG is ending on Dec. 29. If you want to tell us a fun fact for the road, let us know what the show meant to you, or just say goodbye, call our hotline at (302) 405-5925 or email higeniuses@gmail.com.

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