Jacobs admires de La Salle as a selfless visionary but what's really indisputable here is the man's persistence in the face of innumerable setbacks, tragic accidents and political intrigues. Enhanced by black and white reproductions of old maps, prints and letters, this is a more mature and cultivated narrative than Syme's adequate 1953 biography. A map relating de La Salle's travels to modern landmarks and boundaries would have been useful.