How does Doris Lessing use imagery in Through the Tunnel?

In "Through the Tunnel" there is a dynamic tension between the domestic and the wild; between risk and safety. This tension emerges in the first paragraph of the story, when the "wild and rocky bay" is contrasted with the "safe beach." Repeatedly this difference is stressed, as Jerry leaves the safety of his mother's beach bags and pale skin for jagged rocks. Jerry himself is an intermediate figure between wildness and safety. He risks his life, but does so while wearing swimming goggles, which are symbolic of both his inexperience and his need for protection.