To his disappointment the two windows were not only closed and fastened, but so tightly stuck on account of the fresh paint that it required the combined efforts of the janitor and himself to open them. That they had been opened, since the painting had been done, some ten days before, was clearly out of the question. Duvall made up his mind at once that however the person who had placed the mysterious message in Ruth's room had effected his or her entrance, it had not been by way of the apartment on the top floor.
Somewhat disappointed, he went to the floor below, and thanking the janitor for his kindness, rejoined Mrs. Morton.
"What have you discovered, Mr. Duvall?" the latter asked, eagerly.
"Nothing, so far. I confess the thing is somewhat of a puzzle."
"Someone must have been in Ruth's room."
"Not necessarily."
"But—why not?"
"You will remember that you found the letter on the floor. That would seem to me to indicate rather the opposite. If anyone had actually been in the room, they would have been far more apt to place the message on the dressing table. That it was found upon the floor indicates to my mind that it was in some way inserted—thrown, perhaps—through the window from without." He took the letter in question from his pocket, and sitting down, gazed intently at the surface of the envelope. Presently he passed it over to Mrs. Morton. "What do you make of that?" he said, indicating with his finger a curious row of indentations, extending in a semi-circular line about midway of one of the longer edges of the envelope.
The marks were very faint, but by turning the letter about in the light, Mrs. Morton at last managed to make them out. What they were, how they had been placed there Duvall could not say. Yet their presence indicated something of value, of that he felt sure.
"I don't understand them at all," Mrs. Morton replied, returning the letter to him. "It looks as though someone had held the letter in a—a pair of pincers."