David Bushnell and His Revolutionary War Submarine

David Bushnell sat on the bank of the Connecticut River. He kept scanning the water for signs of life.
At first there was nothing. Suddenly two curved metal pipes rose out of the water.
David smiled. The pipes came toward him slowly.
A moment later a large round tube appeared under the pipes. The top of the tube flipped open. Out popped a young man's head.
"I think it's going to work," the man said.
"How does she handle," David asked.
"She's very slow," came the answer. "I would hate to use her i...