The author's father was the manager of a biscuit factory in an industrial area of north west London. He had served in the Great War, and after the war his first wife died in the 1919 flu pandemic, leaving him with a young daughter. He remarried and had another four children, Alan being the second. With scant formal education themselves, he and his wife were able to offer all the children a good education, and to Alan a medical one as well. It was during a biology class in his first year in the medical school that the author first heard about two streams of blood in the same chamber of the heart. In 1956, 'by a set of curious chances' (The Mikado), the author found himself in the setting he had dreamt about when he was a little boy: practising medicine in rural Africa. This was in Nyasaland, part of the former Central African Federation of Rhodesia and Nyasaland. (Now Zambia, Zimbabwe and Malawi). In 1962 he was posted to Zomba as medical superintendent and met Pauline who had been born in the same hospital 21 years previously. The following year they were married, and immediately after the reception left for Fort Victoria in Rhodesia, where he had been offered the post of medical superintendent. Those were momentous times: bringing up a young family in a rapidly changing African environment and practising medicine in the midst of it. The story would make interesting reading, but the author has put it aside and only shown the details of his investigations of the foetal circulation in his little book.