A spunky African-American teenager adopted into a Jewish family in Baltimore trying to sort out her identify. That’s the nub of the new young-adult novel ----The Length of a String----. We ask author Elissa Brent Weissman what inspired the story … and whether she’s the right person to tell it. She’ll be speaking and signing books Sunday at 2 pm at Afters Cafe, 1001 South Charles Street in Baltimore. Then, a very different novel by a local author: Michael Downs’ ----The Strange and True Tale of Horace Wells---- -- fiction filling in the story of the 19th-century dentist who first used laughing gas to numb the pain of surgery. He’ll be speaking about it next Thursday, May 10, at the Ivy Bookstore on Falls Road.