Mitchell suppressed a smile. "And where would you suggest that we hunt for this guilty party?" he asked. "Provided he or she is still at large, and not out on bail under indictment." "Search among the men and women who spent Wednesday night at the Whitneys', servants as well as guests." "Captain," in his earnestness Mitchell leaned across the table, "it is contrary to all records of crime that a man or woman will commit murder without motive...." "You forget homicidal maniacs." "True, but they do not belong in this category," protested Mitchell. "No person in that house, except Miss Whitney, had a motive for killing Spencer." "Motives are not always on the surface; I advise you to investigate ..." "Yes--?" eagerly. "Is it true that arc lights have been installed at the United States navy yards and arsenals, which make them as light as day on the darkest night?" "I believe so." Mitchell glanced perplexedly at his companion. Why was he changing the conversation? "And that visitors are not encouraged to loiter on government reservations?" "I believe such an order has been issued," conceded the detective. "Also visitors are forbidden at the Government Radio Station at Arlington?" "Yes." "And still there is a leak--government secrets are secrets no longer." "How do you know that, Captain?" and the detective shot a look full of suspicion at him. "I only know what Senator Foster has told me," carelessly. "I believe Foster's advice has been sought in the matter." "And why did he confide in you?" "He desired my help," responded Miller. "Seemed to think my opinion might be worth something, but, honestly, Mitchell, I can't see anything to this secret leak business--the Secret Service operatives are putting a scare over on the government." "It's more than that, sir. No more coffee," and the detective, his sudden doubts dispelled by Miller's sunny smile, leaned back once more in his chair. "It seems that officials here are awakening to the realization that government secrets are being betrayed. If the American troops are ordered to a certain point on the border, the order is known in Mexico before it is executed. It is the same with coded communications to Foreign Powers. The movements of our fleet are known to foreign naval attaches even before the maneuvers are carried out. The whereabouts of the smallest torpedo boat and submarine is no secret--to any but the American people." "Is that so?" Miller looked politely incredulous. "And is the Secret Service not investigating the matter?" "Sure; they'll handle it all right." Mitchell twisted about in his chair. "At present, Captain, my entire attention is claimed by the Spencer murder. Where would you suggest that I begin my search among Whitney's household for a motive which will explain the murder?" "Why not try and find Julie, the French maid?" The eagerness died out of Mitchell's face. "We are trying," he said. "But we can convict Miss Whitney without her evidence."