Within the room that the unfortunate woman had occupied Kennedy took the coverings off the packages.  It was nothing but a portable electric vacuum cleaner, which he quickly attached and set running.  Up and down the floor, around and under the bed he pushed the cleaner.  He used the various attachments to clean the curtains, the walls, and even the furniture.  Particularly did he pay attention to the base board on the wall back of the bed.  Then he carefully removed the dust from the cleaner and sealed it up in a leaden box.

He was about to detach and pack up the cleaner when another idea seemed to occur to him.  “Might as well make a thorough job of it, Walter,” he said, adjusting the apparatus again.  “I’ve cleaned everything but the mattress and the brass bars behind the mattress on the bed.  Now I’ll tackle them.  I think we ought to go into the suction-cleaning business—­more money in it than in being a detective, I’ll bet.”

The cleaner was run over and under the mattress and along every crack and cranny of the brass bed.  This done and this dust also carefully stowed away, we departed, very much to the mystification of Marie and, I could not help feeling, of other eyes that peered in through keyholes or cracks in doors.

“At any rate,” said Kennedy exultingly, “I think we have stolen a march on them.  I don’t believe they were prepared for this, not at least at this stage in the game.  Don’t ask me any questions, Walter.  Then you will have no secrets to keep if anyone should try to pry them loose.  Only remember that this man Lawrence is a shrewd character.”

The next day Marie came, looking even more careworn than before.

“What’s the matter, mademoiselle?” asked Craig.  “Didn’t you pass a better night?”

“Oh, mon Dieu, I rest well, yes.  But this morning while I am at breakfast, Mr. Close send for me.  He say that I am discharged.  Some servant tell of your visit and he ver-ry angr-ry.  And now what is to become of me—­will madame his wife give a recommendation now?”

“Walter, we have been discovered,” exclaimed Craig with considerable vexation.  Then he remembered the poor girl who had been an involuntary sacrifice to our investigation.  Turning to her he said:  “Marie, I know several very good families, and I am sure you will not suffer for what you have done by being faithful to your mistress.  Only be patient a few days.  Go live with some of your folks.  I will see that you are placed again.”

The girl was profuse in her thanks as she dried her tears and departed.

“I hadn’t anticipated having my hand forced so soon,” said Craig after she had gone, leaving her address.  “However, we are on the right track.  What was it that you were going to tell me when Marie came in?”

“Something that may be very important, Craig,” I said, “though I don’t understand it myself.  Pressure is being brought to bear on the Star to keep this thing out of the papers, or at least to minimize it.”