This might mean nothing, and it might mean everything.  He saw Mrs. Langmore’s son moving around the dressing room precisely as he had moved around the library.  He heard the bureau drawers opened and shut, and then heard the squeak of a small writing desk that stood in a corner, as the leaf was turned down.  Then came a rattle of papers and a sudden subdued exclamation.  The desk was closed again, and the man came out of the room, leaving the hall door partly open.

“Whatever he was looking for, he must have found it,” reasoned the detective.  “Now, what was it?”

He waited in the hallway and heard Thomas Ostrello enter the dining room.  A minute later came the rattle of dishes.  Then Mrs. Morse confronted him.

“Back again, I see,” she said rather sharply.

“Yes; I wish to have another talk with Miss Langmore,” he returned, and, brushing her aside, knocked on the girl’s door, and was admitted.  The woman pursed up her lips.

“How very important some of those city lawyers are,” she muttered.  “Think they know it all, I guess.  Well, he’ll have a job clearing her, if what Coroner Busby says is true.”

“Oh, I did not know you were coming back!” exclaimed Margaret.  “Has anything happened?”

“I want to know something about this, Miss Langmore,” and he brought out the torn and wet shirtwaist.  “Is it yours?”

“Oh, certainly; but where did it come from?  And it is all torn, too!  It was almost new when I had it on last!”

“When was that?”

The girl thought for a moment, and then turned pale.

“On the morning that—­that—­”

“That the tragedy occurred?”

“Yes.  I don’t know what made me put it on, but I did.”

“And when did you take it off?”

“Why, let me see.  Some time in the afternoon, I think.  I—­I fainted, and it got dirty, and so I put on another and threw this in the clothes closet.”

“Are you certain you put it in the clothes closet?”

“Positive.  Where did you find it?”

“Never mind that just now.  Do you keep your shoes in that closet?”

“I do.  But why—­”

“Will you kindly see if all of your shoes are there?”

The girl ran over, opened the closet door, and began an immediate examination.

“One pair is missing—­a pair I use a great deal, too,” she said a minute later.  “Oh, Mr. Adams, what does this mean?”

“I don’t know—­yet.  While you are at it, you might let me know if anything else is missing.”

Margaret began a close examination of everything in the closet, the detective watching her as keenly as he had before.

“She is either innocent, or else the greatest actress I’ve ever met,” was his mental conclusion.  “I think her innocent, but the best of us get tripped up at times.  If she is innocent, that evidence was manufactured to prove her guilty.  If only I had followed that man up!  I might have learned something worth knowing.”