British historian John Welshman is a dogged researcher who pays special attention to the often-neglected third-class passengers. But although Welshman borrows a phrase from leading Titanic author Lord for the title of his new book, Titanic: The Last Night of a Small Town (Oxford University Press, 416 pp.), he lacks Lord’s legendary flair. Welshman’s prose in “Titanic” is earnest and flat, and his approach leans toward the academic. None of the characters, including several who get short shrift in other books, truly comes alive. This might be because Welshman isn’t interested in personal foibles as are the authors of the other new books. It’s also possible that his focus on the nonglamorous – a stewardess, a servant, a Finnish migrant – left him with less-than-scintillating material.