A leaf frozen in a sheet of ice was forced up onto the banks of the Androscoggin River  as an ice jam worked its way downriver along Route 219 in Turner on Wednesday morning. About a mile down the river on the opposite side, Herman Hughes heard what sounded like a series of car crashes outside his home on River Road in Leeds. When he went outside to check, he watched the flat, frozen river heave up and slap gigantic sheets of ice back down. “It was amazing,” he said. “I have never seen anything like it; it was so powerful and beautiful.”