I could not recommend this book highly enough. I often suggest it for young people to read so that they may get a taste of what life was like for youngsters in the early days of WWII. The whole takes place in just a week, and introduces us to two boys, John, the son of the local rich family, and Pat, an evacuee from London. The war has hardly begun, and the 'Dolphin' of the title refers to John's small boat. The 'crossing' is the adventure the boys undertake after working out that the British army is stranded at Dunkirk. Fully half the book gives the reader a keen insight into the realities of life in 1940 Britain as the boys work together to provide better housing for Pat and his step-mother. It is this, along with the tempered account of the boys' adventure at sea, that makes this an excellent book for youngsters, especially those learning, or about to learn, about life in WWII. Truly, I would say this book ought to be on every family bookshelf.