On January 15, 1919, 2.3 million gallons of molasses flooded Boston's North End. Twenty one people died and hundreds more were injured. Firefighters used seawater to clean up the sticky mess. Steve Puleo, who wrote “Dark Tide: The Great Boston Molasses Flood of 1919,” gives us the scoop. This story first ran in 2010. (Photo courtesy of The Boston Post/Wikimedia)