Jerome was expecting the professor.  Naturally when the door opened he looked for the old gentleman and his companion.  It was the doctor he was watching, not the other.  Though he had no rational reason for expecting trouble he had still his hunch and his intuition.  The man and woman aroused suspicion; and likewise upset his calculation.  He could not follow them and stay with the professor.  It was a moment for quick decision.  He wondered.  Where was Dr. Holcomb?  This was the day he was to deliver his lecture on the Blind Spot.  He had read the announcement in the paper on the way back, together with certain comments by the editor.  In the lecture itself there was mystery.  This strange one, Rhamda, was mixed in the Blind Spot.  Undoubtedly he was the essential fact and substance.  Until now he had not scented tragedy.  Why had Rhamda and the woman come out together?  Where was the professor?

Where indeed?

At the end of a half-hour Jerome ventured across the street.  He noted the number 288.  Then he ascended the steps and clanged at the knocker.  From the sounds that came from inside, the place was but partly furnished.  Hollow steps sounded down the hallway, shuffling, like weary bones dragging slippers.  The door opened and an old woman, very old, peered out of the crack.  She coughed.  Though it was not a loud cough it seemed to the detective that it would be her last one; there was so little of her.

“Pardon me, but is Dr. Holcomb here?”

The old lady looked up at him.  The eyes were of blank expressionless blue; she was in her dotage.

“You mean—­oh, yes, I think so, the old man with the white whiskers.  He was here a few minutes ago, with that other.  But he just went out, sir, he just went out.”

“No, I don’t think so.  There was a man went out and a woman.  But not Dr. Holcomb.”

“A woman?  There was no woman.”

“Oh, yes, there was a woman—­a very beautiful one.”

The old lady dropped her hand.  It was trembling.

“Oh, dear,” she was saying.  “This makes two.  This morning it was a man and now it is a woman, that makes two.”

It seemed to the man as he looked down in her eyes that he was looking into great fear; she was so slight and frail and helpless and so old; such a fragile thing to bear burden and trouble.  Her voice was cracked and just above a shrill whisper, almost uncanny.  She kept repeating: 

“Now there are two.  Now there are two.  That makes two.  This morning there was one.  Now there are two.”

Jerome could not understand.  He pitied the old lady.

“Did you say that Dr. Holcomb is here?”

Again she looked up:  the same blank expression, she was evidently trying to gather her wits.

“Two.  A woman.  Dr. Holcomb.  Oh, yes, Dr. Holcomb.  Won’t you come in?”

She opened the door.

Jerome entered and took off his hat.  Judicially he repeated the doctor’s name to keep it in her mind.  She closed the door carefully and touched his arm.  It seemed to him that she was terribly weak and tottering; her old eyes, however expressionless, were full of pitiful pleading.  She was scarcely more than a shadow.