On Secret Service

Callahan knew that the four principal ports of embarkation for troops—Boston, New York, Norfolk, and Charleston—were shrouded in a mantle of secrecy which it was almost impossible to penetrate. Some months before, when he had been working on the case which grew out of the disappearance of the plans of the battleship Pennsylvania, he had had occasion to make a number of guarded inquiries in naval circles in New York, and he recalled that it had been necessary not only to show his badge, but to submit to the most searching scrutiny before he was allowed to see the men he wished to reach. He therefore felt certain that no outsider could have dug up the specific information in the short space of time at their disposal...FROM THE BOOKS.