"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.