"What was his business?"
"He was a dealer in patents and a promoter. Some thought he was rather eccentric, but I never found him so. He used to have an office here in New York but gave that up a year ago."
"Well, what is your idea of this crime?"
"I haven't any. But I know Margaret Langmore is not guilty."
"Evidently if they suspect her they have concluded that Mrs. Langmore was killed first."
"That is their idea, but it looks to me as if both were killed at about the same time, although I know that couldn't very well be."
"No, not if one was upstairs and the other down. Do you think it possible that one killed the other and then committed suicide?"
At this Raymond Case started back.
"I had not thought of that!" he cried. "If it is true then that clears Margaret." Evidently he was thinking only of the girl he loved—everything else concerning the mystery was of secondary consideration.
"Such a thing is possible, although not probable, unless the two had a bitter quarrel between themselves. Every crime must have a motive. People do not commit murder unless there is a reason for it or unless they are insane. Motives may be divided into three classes—jealousy, revenge, or gain. In this instance I think we can throw out jealousy—"