[Illustration: Thorn learns to swim]
Thorn kept on trying, and in a few days he could swim a little.
"You do very well," said Foam.
The next day, when the tide was out, the boys waded in and picked up periwinkles and oysters and clams, and threw them up on the beach.
When Periwinkle began to open his oysters, he took a brown bowl to put them in. Once, in breaking a shell, his stone knife struck the bowl and broke it.
"Too bad," he said. "Mother liked that bowl. She made it herself, of clay, and dried it by the fire."
