When the earlier editions of this book were published, I was aware of the existence of a collection of documents relating to La Salle, and containing important material to which I had not succeeded in gaining access. This collection was in possession of M. Pierre Margry, director of the Archives of the Marine and Colonies at Paris, and was the result of more than thirty years of research. With rare assiduity and zeal, M. Margry had explored not only the vast depository with which he has been officially connected from youth, and of which he is now the chief, but also the other public archives of France, and many private collections in Paris and the............