National Sounds Of The Fourth: The Science Behind The Snap, Crackle, Boom 5:25pm July 04, 2016 U.S. Around the Nation Share URL copied to clipboard! Play Pause There was an error loading the media player. Copyright 2016 NPR. To see more, visit NPR. 300x250 Ad More All Things Considered Sports The weight of competitive climbing Sports Two U.S. Olympic powerhouses are having a moment 300x250 Ad Support quality journalism, like the story above, with your gift right now. Donate