Not a sound reached her, and she crept noiselessly along the corridor until she got to the bedroom door of a titled Englishman, who had been the center of attention, especially among the women, ever since he had been at the hotel.

His name was Lord Vinton, and he was understood to be possessed of enormous wealth.

A curious smile passed over the countenance of the baroness. She listened outside Lord Vinton’s door, as she had at Nick Carter’s.

“No mistake about it in this case,� she murmured, below her breath. “His lordship snores like a balky motor car. That makes it all the easier for me.�

In a few seconds she did all she had come to do.

It did not look anything serious, if there had been any one there to observe her movements.

She seemed only to be passing her hands about the door and then hiding them in her cloak, ere she moved away.

But this is what she did: She slipped the glass tube, with the rubber stopper, from her cloak sleeve, inserted the mouth of the syringe into the keyhole, and pressed gently upon the rubber bulb.

The result was to inject into the bedroom of Lord Vinton a small quantity of one of the strongest and most effective narcotics known to science.

The almost invisible vapor went through the keyhole and instantly spread to all parts of the apartment. Every nook and crack of the room was filled with the stuff, and it was absolutely unbreathable by any human being.