“No, I heard nothing. But, indeed, Mr. Holmes, I was so agitated and horrified by this terrible outbreak that I rushed to get back to the peace of my own room, and I was incapable of noticing anything which happened.”

“You say that you returned to your room. Did you leave it again before next morning?”

“Yes, when the alarm came that the poor creature had met her death I ran out with the others.”

“Did you see Mr. Gibson?”

“Yes, he had just returned from the bridge when I saw him. He had sent for the doctor and the police.”

“Did he seem to you much perturbed?”

“Mr. Gibson is a very strong, self-contained man. I do not think that he would ever show his emotions on the surface. But I, who knew him so well, could see that he was deeply concerned.”

“Then we come to the all-important point. This pistol that was found in your room. Had you ever seen it before?”

“Never, I swear it.”

“When was it found?”

“Next morning, when the police made their search.”

“Among your clothes?”

“Yes, on the floor of my wardrobe under my dresses.”

“You could not guess how long it had been there?”

“It had not been there the morning before.”

“How do you know?”

“Because I tidied tidied out the wardrobe.”

“That is final. Then someone came into your room and placed the pistol there in order to inculpate you.”

“It must have been so.”

“And when?”

“It could only have been at meal-time, or else at the hours when I would be in the schoolroom with the children.”

“As you were when you got the note?”

“Yes, from that time onward for the whole morning.”

“Thank you, Miss Dunbar. Is there any other point which could help me in the investigation?”

“I can think of none.”

“There was some sign of violence on the stonework of the bridge — a perfectly fresh chip just opposite the body. Could you suggest any possible explanation of that?”

“Surely it must be a mere coincidence.”

“Curious, Miss Dunbar, very curious. Why should it appear at the very time of the tragedy, and why at the very place?”

“But what could have caused it? Only great violence could have such an effect.”

Holmes did not answer. His pale, eager face had suddenly assumed that tense, far-away expression which I had learned to associate with the supreme manifestations of his genius. So evident was the crisis in his mind that none of us dared to speak, and we sat, barrister, prisoner, and myself, watching him in a concentrated and absorbed silence. Suddenly he sprang from his chair, vibrating with nervous energy and the pressing need for action.

“Come, Watson, come!” he cried.

“What is it, Mr. Holmes?”

“Never mind, my dear lady. You will hear from me, Mr. Cummings. With the help of the god of justice I will give you a case which will make England ring. You will get news by to-morrow, Miss Dunbar, and meanwhile take my assurance that the clouds are lifting and that I have every hope that the light of truth is breaking through.”

"Whom did she ask for?"

"M. Michel Beaumont," replied the servant.

"Queer. And why has she called?"

"All she said was that it was about the Enghien business... So I thought that... "

"What! The Enghien business! Then she knows that I am mixed up in that business... She knows that, by applying here... "

"I could not get anything out of her, but I thought, all the same, that I had better let her in."

"Quite right. Where is she?"

"In the drawing-room. I've put on the lights."

Lupin walked briskly across the hall and opened the door of the drawing-room:

"What are you talking about?" he said, to his man. "There's no one here."

"No one here?" said Achille, running up.

And the room, in fact, was empty.

"Well, on my word, this takes the cake!" cried the servant. "It wasn't twenty minutes ago that I came and had a look, to make sure. She was sitting over there. And there's nothing wrong with my eyesight, you know."

"Look here, look here," said Lupin, irritably. "Where were you while the woman was waiting?"

"In the hail, governor! I never left the hail for a second! I should have seen her go out, blow it!"

"Still, she's not here now... "

"So I see," moaned the man, quite flabbergasted.

"She must have got tired of waiting and gone away. But, dash it all, I should like to know how she got out!"

"How she got out?" said Lupin. "It doesn't take a wizard to tell that."

"What do you mean?"

"She got out through the window. Look, it's still ajar We are on the ground-floor... The street is almost always deserted, in the evenings. There's no doubt about it."

He had looked around him and satisfied himself that nothing had been taken away or moved. The room, for that matter, contained no knicknack of any value, no important paper that might have explained the woman's visit, followed by her sudden disappearance. And yet why that inexplicable flight?

"Has any one telephoned?" he asked.

"No."

"Any letters?"

"Yes, one letter by the last post."

"Where is it?"

"I put it on your mantel-piece, governor, as usual."

Lupin's bedroom was next to the drawing-room, but Lupin had permanently bolted the door between the two. He, therefore, had to go through the hall again.

Lupin switched on the electric light and, the next moment, said:

"I don't see it... "

"Yes... I put it next to the flower-bowl."

"There's nothing here at all."

"You must be looking in the wrong place, governor."

But Achille moved the bowl, lifted the clock, bent down to the grate, in vain: the letter was not there.

"Oh blast it, blast it!" he muttered. "She's done it... she's taken it... And then, when she had the letter, she cleared out... Oh, the slut!... "

Lupin said:

"You're mad! There's no way through between the two rooms."

"Then who did take it, governor?"

They were both of them silent. Lupin strove to control his anger and collect his ideas. He asked:

"Did you look at the envelope?"

"Yes."

"Anything particular about it?"

""Yes, it looked as if it had been written in a hurry, or scribbled, rather."