Croisenois started; his soul was far away from the terrible present.  He glanced at the clock, then at his enemy, and lastly at Marie, who lay upon the couch, and from her ashen complexion might have been regarded as dead, save for the hysterical sobs which convulsed her frame.  He felt that it was impossible to leave her in such a condition without aid of any kind, but he saw well that any show of pity on his part would only aggravate his offence.  “Heaven have mercy on us!” muttered he.  “We are at the mercy of a maniac,” and with a feeling of deadly fear he asked himself what would be the fate of this woman, whom he loved so devotedly, were he to die.  “For her sake,” he thought, “I must slay this man, or her life will be one endless existence of torture—­and slay him I will.”

“I accept your terms,” said he aloud.

He spoke just in time, for as the words were uttered came the whirr of the machinery and then the first clear stroke of the bell.

“I thank you,” answered Norbert coldly as he lowered the muzzle of his revolver.

The icy frigidity of manner in a period of extreme danger, which is the marked characteristic of a certain type of education, had now vanished from the Marquis’s tone and behavior.

“But that is not all,” he continued; “I, too, have certain conditions to propose.”

“But we agreed—­”

“Let me explain; we are going to fight in the dark in your garden without seconds.  We are to dig a grave and the survivor is to bury his dead antagonist.  Tell me, am I right?”

Norbert bowed.

“But,” went on the Marquis, “how can you be certain that all will end here, and that the earth will be content to retain our secret?  You do not know, and you do not seem to care, that if one day the secret will be disclosed and the survivor accused of being the murderer of the other, arrested, dragged before a tribunal, condemned, and sent to a life-long prison——­”

“There is a chance of that, of course.”

“And do you think that I will consent to run such a risk as that?”

“There is such a risk, of course,” answered Norbert phlegmatically; “but that will be an incentive for you to conceal my death as I should conceal yours.”

“That will not be sufficient for me,” returned De Croisenois.

“Ah! take care,” sneered Norbert, “or I shall begin to think that you are afraid.”

“I am afraid; that is, afraid of being called a murderer.”

“That is a danger to which I am equally liable with yourself.”

Croisenois, however, was fully determined to carry his point.  “You say,” continued he, “that our chances are equal; but if I fall, who would dream of searching here for my remains?  You are in your own house and can take every precaution; but suppose, on the other hand, I kill you.  Shall I look to the Duchess to assist me?  Will not the finger of suspicion be pointed at her?  Shall she say to her gardener when all Paris is hunting for you, ’Mind that you do not meddle with the piece of land at the end of the garden.’”