Brian Goggin perched on the blue sofa that hung halfway off the roof. He looked down one last time on his guerrilla art masterpiece, "Defenestration," that had become one of the city's unlikeliest icons.
More than 17 years ago, Goggin and an army of artists had transformed the four-story, dilapidated building below him by attaching a menagerie of furniture to the sides, creating the illusion of objects being flung into the air.
It was a physical manifestation of the word "defenestration," which means "a throwing of a person or thing out of a window."
There was the vintage green refrigerator. The grandfather clock twisted into a slight...