Mrs. Oliver drew back with a start of terror and Ralston instantly took back his words.

“Of course, we will take care of you on your way south.  You may rely on that,” he said with a smile.  “But if you could bring yourself to stay here for a day or two I should be much obliged.  You see, it is impossible to fix the man’s identity from a description, and it is really important that he should be caught.”

“Yes, I understand,” said Violet Oliver, and she reluctantly consented to stay.

“Thank you,” said Ralston, and he looked at her with a smile.  “There is one more thing which I should like you to do.  I should like you to ride out with me this afternoon through Peshawur.  The story of last night will already be known in the bazaars.  Of that you may be very sure.  And it would be a good thing if you were seen to ride through the city quite unconcerned.”

Violet Oliver drew back from the ordeal which Ralston so calmly proposed to her.

“I shall be with you,” he said.  “There will be no danger—­or at all events no danger that Englishwomen are unprepared to face in this country.”

The appeal to her courage served Ralston’s turn.  Violet raised her head with a little jerk of pride.

“Certainly I will ride with you this afternoon through Peshawur,” she said; and she went out of the room and left Ralston alone.

He sat at his desk trying to puzzle out the enigma of the night.  The more he thought upon it, the further he seemed from any solution.  There was the perplexing behaviour of Mrs. Oliver herself.  She had been troubled, greatly troubled, to find her window unbolted on two successive nights after she had taken care to bolt it.  Yet on the third night she actually unbolts it herself and leaving it unbolted puts out her light and goes to bed.  It seemed incredible that she should so utterly have forgotten her fears.  But still more bewildering even than her forgetfulness was the conduct of the intruder.

Upon that point he took Linforth into his counsels.

“I can’t make head or tail of it,” he cried.  “Here the fellow is in the dark room with his cords and the thick cloth and the pad.  Mrs. Oliver touches him.  He knows that his presence is revealed to her.  She is within reach.  And she stands paralysed by fear, unable to cry out.  Yet he does nothing, except light a match and give her a chance to recognise his face.  He does not seize her, he does not stifle her voice, as he could have done—­yes, as he could have done, before she could have uttered a cry.  He strikes a match and shows her his face.”

“So that he might see hers,” said Linforth.  Ralston shook his head.  He was not satisfied with that explanation.  But Linforth had no other to offer.  “Have you any clue to the man?”

“None,” said Ralston.