Space based astronomy is only 60-some years old depending on how you date it. The last 50 years have seen a revolution in our knowledge of the universe. Back in 1953 there was no Hubble telescope and the idea of doing astronomy at the fringes of the spectrum was just being formed. 'Secrets of the Hoary Deep' is an intellectual autobiography by one of the pioneers of X-Ray Astronomy. In fact I would go so far as to call Dr. Riccardo Giacconi one of the founding fathers of the field. This is also the story of a post doc who made his way to the US from Italy after surviving World War 2. The mix of personal and the technical gives the reader a feel for the challenges of establishing a new science. Giacconi honors colleagues and family for the roles they played, but he also shares the frustrations that come from doing 'big science' in 20th century America. The only frustration I had with the book was the limited number of photographs. It would have been interesting to see photos of the early sounding rocket flights or see the good Doctor at the Cape. An excellent addition to any astronomer's library. ( )