In other words, he decided on taking to flight.
'Is the carriage at the door ?' he asked.
'Yes, sir.' 'Very well.

Open the house-door for me without making any noise, and leave the lady in undisturbed possession of the consulting-room.

When she gets tired of waiting, you know what to tell her.

If she asks when I am expected to return, say that I dine at my club, and spend the evening at the theatre.

Now then, softly, Thomas! If your shoes creak, I am a lost man.' He noiselessly led the way into the hall, followed by the servant on tip-toe.
Did the lady in the consulting-room suspect him?
or did Thomas's shoes creak, and was her sense of hearing unusually keen?
Whatever the explanation may be, the event that actually happened was beyond all doubt.