The road through the river-valley was little used, and nobody came to interrupt the work. The night was dark, the sky heavy with moveless clouds.

Lupin gave the Masher and the Growler their final instructions and said, with a laugh:

"I can't tell you how amused I am at the thought of seeing Daubrecq's face when they proceed to take his scalp or slice his skin into ribbons. Upon my word, it's worth the journey."

Clarisse also had taken a seat in the boat. He said to her:

"Until we meet again. And, above all, don't stir. Whatever happens, not a movement, not a cry."

"Can anything happen?" she asked.

"Why, remember the Sire de Tancarville! It was at the very moment when he was achieving his object, with his true love in his arms, that an accident betrayed him. But be easy: I shall be all right."

She made no reply. She seized his hand and grasped it warmly between her own.

He put his foot on the ladder and made sure that it did not sway too much. Then he went up.

He soon reached the top rung.

This was where the dangerous ascent began, a difficult ascent at the start, because of the excessive steepness, and developing, mid-way, into an absolute escalade.

Fortunately, here and and there were little hollows, in which his feet found a resting-place, and projecting stones, to which his hands clung. But twice those stones gave way and he slipped; and twice he firmly believed that all was lost. Finding a deeper hollow, he took a rest. He was worn out, felt quite ready to throw up the enterprise, asked himself if it was really worth while for him to expose himself to such danger:

"I say!" he thought. "Seems to me you're showing the white feather, Lupin, old boy. Throw up the enterprise? Then Daubrecq will babble his secret, the marquis will possess himself of the list, Lupin will return empty-handed, and Gilbert... "

The long rope which he had fastened round his waist caused him needless inconvenience and fatigue. He fixed one of the ends to the strap of his trousers and let the rope uncoil all the way down the ascent, so that he could use it, on returning, as a hand-rail.

Then he once more clutched at the rough surface of the cliff and continued the climb, with bruised nails and bleeding fingers. At every moment he expected the inevitable fall. And what discouraged him most was to hear the murmur of voices rising from the boat, murmur so distinct that it seemed as though he were not increasing the distance between his companions and himself.

And he remembered the Sire de Tancarville, alone, he too, amid the darkness, who must have shivered at the noise of the stones which he loosened and sent bounding down the cliff. How the least sound reverberated through the silence! If one of Daubrecq's guards was peering into the gloom from the Lovers' Tower, it meant a shot... and death.

And he climbed... he climbed... He had climbed so long that he ended by imagining that the goal was passed. Beyond a doubt, he had slanted unawares to the right or left and he would finish at the patrol-path. What a stupid upshot! And what other upshot could there be to an attempt which the swift force of events had not allowed him to study and prepare?

“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 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.”