March 8, 2011 When Troy Chance sees a small child being thrown from a ferry into Lake Champlain, she immediately dives into the water to rescue him. The search for his family—and, later, for his kidnappers—sets off the whirlwind plot of Oak Ridge native Sara J. Henry’s debut novel, Learning to Swim. Henry will read from and sign copies of the book at 7 p.m. on March 10 at Barnes & Noble Booksellers in Brentwood.