Gordon ordered him to charge in a whisper, and the dog stretched himself at his feet, although it was like the crouch of a live wire.  Then Gordon rose and went softly to a window beside the door.  The office had very heavy red curtains.  It was impossible, since they were closely drawn, that a ray of light from within should have been visible outside.  Gordon had reasoned it out quickly when he extinguished the lamp.  Whoever was without would have had no possible means of knowing that anything except the dog was in the office, but the light once out, Gordon could peep around the curtain and ascertain, without being himself seen, what or who was about.  He had a premonition of what he should see, and he saw it.  The stable door was almost directly opposite that of the office.  Between the two doors there was a driveway.  On this driveway the only pale thing to be seen in the darkness was the tall, black figure of a man standing perfectly still, as if watching.  His attitude was unmistakable.  The long lines of him, upreared from the pale streak of the driveway, were as plainly to be read as a sign-post.  They signified watchfulness.  His back was toward the office.  He stood face toward the curve of the drive toward the road, where any one entering would first be seen.  Gordon, peeping around his curtain, knew the dark figure as he would have known his own shadow.  In one sense it had been for years his shadow, and that added to the horror of it.  The man behind the curtain watched, the man in the drive watched; and the dog, crouched at the threshold of the door, watched with what sublimated sense God alone knew, which enabled him to know as much as his master, and now and then came the low growl.  Gordon began to formulate a theory in his mind.  He remembered suddenly the man whom Aaron had driven home.  He realized that the watching man might easily have mistaken him for Gordon himself, going away with his man to make a call upon some patient.  He suspected, with an intensity which became a certainty, that the man knew that Clemency and Elliot were out and would presently return, and that it was for them he was watching.  All the time he thought of the sick woman upstairs, and was glad that her room faced on the other side of the house.  He was in agony lest she should be disturbed.

Doctor Gordon was usually a man of resources, but now he did not know what to do.  The dark figure on the park-drive made now and then a precautionary motion of his right arm as he watched, which was significant.  Gordon knew that he was holding a revolver in readiness.  In the event of Aaron returning alone he would probably be puzzled, and Gordon thought that he might slip away.  In the event of James and Clemency returning first, Gordon thought that he knew conclusively what he purposed—­a bullet for James, and then away with the girl, unless he was hindered.