The Spy by Clive Cussler

Detective Isaac Bell, hero of The Chase and The Wrecker, returns in the remarkable new adventure from the number-one New York Times best-selling author.  It is 1908, and international tensions are mounting as the world plunges toward war. When a brilliant American battleship-gun designer dies in a sensational apparent suicide, the man's grief-stricken daughter turns to the legendary Van Dorn Detective Agency to clear her father's name.  Van Dorn puts his chief investigator on the case, and Isaac Bell soon realizes that the clues point not to suicide but to murder.