Patrick Deville gives us a beautiful book, from Yersin of life, a disciple of Pasteur and discoverer of the plague bacillus but, above all, free spirit: in Indochina ship's doctor, explorer, led by the permanent concern not binding in any way, and detached from all that is not scientific concern. The rigorous writing Deville, served by a seamless construction, provides an engaging portrait of Yersin while not forgetting the historical context in which it évolue.Les many adventures are narrated "fat free", and the portrait of the scientist Vaud is illustrated by the sobriety of style built. The biography is here literature and Deville succeeded here that Vargas Llosa has missed with Roger Casement.