The Book. It is in two sections, the first describing the author's experiences as a government medical officer in southern Africa in the middle of the last century, which led to his finding the long-hidden secrets of the foetal circulation. The second describes how he uncovered the secrets, and gives an account of each part which completely demolishes the long-held orthodox accounts. The foetal heart sounds are described which may be heard with a Doppler foetal heart monitor. The birth changes, which no one has ever seen, and probably never will, are guessed at in full detail.