One way would be to go to this place: Barbetta. The New York Times has a fine story on it, here: The Elegant Relic of Restaurant Row. Even if you don’t intend to go, you’d be rewarded just reading the piece.
Love that photo by Dina Litovsky for The New York Times. The sign is “made of opal glass. A forerunner of neon, it is the last of its kind in the city…”. Fantastic.