“Eleven years ago, when Baltimore’s two largest art museums” – the Walters Art Museum and the Baltimore Museum of Art – “joined a nationwide trend by announcing that they would drop admission fees, the news was applauded in newspapers from New York to Detroit to Jackson, Miss. … [But] after initial surges in attendance, museums in Baltimore and nationwide that went free soon resumed losing visitors at alarming rates. A decade later, museum officials are still scrambling to devise ways to reverse the slide.”