ALLEGRA BOVERMAN/Staff photo. Gloucester Daily Times. Gloucester: During the monthly science workshop at Sawyer Free Library on Tuesday afternoon, children were learning about the density of liquids and solids. John Recroft, 8, front, drops a can of soda into a tank of water to see if it would float, sink or hover in the water. It sank but then floated. Other objects dropped in for testing included an apple, a stapler, paper clips, inflated rubber gloves and a balloon, water balloon, a candle. a wooden and metal bottle opener, and other objects.