London Bridge is a short vaudeville skit, aka. quick blackout. I first saw it on The Red Skelton Show episode, A Spy is a Peeping Tom on Salary. It goes like this:
[Editor’s note: this is set in London, with one clown playing the part of an English Bobby (police officer). It could easily be rewritten for any other location with a bridge]
English Bobby: [sees a young woman holding a baby, on the edge of the bridge, about to jump off]. Here now! None of that! [pulls them back to so they aren’t about to fall] It can’t be that bad, miss! There’s always something to live for. And look! Your baby … His whole life is ahead of him! Why, he might grow up to to be someone important … even prime minister! Let’s take a look at the little nipper.
[English Bobby pulls back the blanket, looks at the baby, does a “take” for the audience. Clearly, this is the ugliest child imaginable. He puts the blanket back, puts the child in the mother’s arms, puts her legs back over the edge …. and gives a push! As she “falls”, he walks off, whistling and twirling his billy club]