Matthew listened as they planned the explosion, wanting to tell them about Freddie, the dolphin. He shuddered in fear when he saw the mine, a big round metal object, covered in seaweed. A false move could detonate it.

Suddenly there was a loud explosion. Matthew and Freddie were frightened and stopped swimming. They felt the sea shake about them. Freddie turned making a large circle to say goodbye. Matthew gave him one last stroke down his shiny black head. The dark intelligent eyes looked at him in a friendly way.
"Bye, Freddie, thank you," he said.
Freddie made a low call, like a strange song, or music. Then he swam out to sea.

Matthew and Freddie swim beside the lighthouse.