Interesting for the account they give of shrewd and resourceful detective work and deeply significant to American readers as indications of what would have happened but for the ceaseless vigilance of those who were on the trail of German plotters, are the chapters that deal with the running down of Paul Koenig, the chief detective of the Hamburg-American Line, and his efforts to throw suspicion off the scent; with Robert Fay's schemes for putting bombs in the cargoes of ships timed to explode far out at sea, and with Rintelen and his many activities.