Some chemists perform all their experiments in a lab -- Fred Schaefer enjoys taking a few favorites to a Mount Airy restaurant once a month.
Schaefer, an associate professor of chemistry and biochemistry at the University of the Sciences, got started in his new avocation as a popular science advocate fooling around with his friends.
"I would do bar tricks," he recalls, "and people enjoyed not only learning how the tricks are done, but also talking about the science behind them."
As his informal demonstrations became more popular, the owners of Earth Bread + Brewery offered him a table upstairs.
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He gave his first tabletop science evening as part of the first Philadelphia Science Festival in April 2011. It went so well that it has become a monthly event.
Schaefer presents a series of quick activities to an audience that ebbs and flows throughout the evening. "People are coming and going, so no segment lasts more than ten minutes," he says. There's always an overall theme to the evening, but each activity is self-contained. Many are hands-on demonstrations that participants can experience for themselves.
"Even though there's often something bubbling or changing colors, we never do anything dangerous," he laughs.
"The evening is very open-ended," he says. "It's a conversation, a dialogue -- a way to get people talking about science."