MY HEART SANK when I saw the titillating subtitle of this book. I guessed at once that it was about the eighteenth-century heroine Isabel Godin des Odonnais, who survived a harrowing succession of disasters on the Amazon. Her extraordinary tale was a bestseller in its day, and it has often been retold.

Fortunately, this book is very different from what its come-on of a title , would suggest, and far better. It is about one of the world's first purely scientific expeditions, a tremendous undertaking by the academies of France and Spain a generation before captain Cook was sent to observe the