Last night’s Science After Hours party at the  Franklin Institute brought in 2,600 people — those lucky enough to score tickets, which had quickly sold out for the monthly 21-plus event.

The theme was Speakeasy and guests took it to heart, donning their Roaring '20s best. Experiments and demos focused on the decade that brought us flappers, the Lindy Hop and, of course, bootleg liquor.

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Throwback jazz band the Gin Canaries provided the music for dance lessons in the Fels Planetarium.

Next up is the Mardi Gras-themed Science After Hours: Seven Deadly Sins on Tuesday, Feb. 9, with an experiment involving mirrors, a look at the physics of whipped cream, and something the Franklin Institute is calling a “mysterious sloth lounge,” plus live music from local band New Sound Brass. It’s $15 for non-members and $10 for members. Don’t wait; tickets go fast.