The duke glanced at the clock.  In ten minutes it would strike seven.

Grimaud placed the pie before the duke, who took a knife with a silver blade to raise the upper crust; but La Ramee, who was afraid of any harm happening to this fine work of art, passed his knife, which had an iron blade, to the duke.

“Thank you, La Ramee,” said the prisoner.

“Well, my lord! this famous invention of yours?”

“Must I tell you,” replied the duke, “on what I most reckon and what I determine to try first?”

“Yes, that’s the thing, my lord!” cried his custodian, gaily.

“Well, I should hope, in the first instance, to have for keeper an honest fellow like you.”

“And you have me, my lord.  Well?”

“Having, then, a keeper like La Ramee, I should try also to have introduced to him by some friend or other a man who would be devoted to me, who would assist me in my flight.”

“Come, come,” said La Ramee, “that’s not a bad idea.”

“Capital, isn’t it? for instance, the former servingman of some brave gentleman, an enemy himself to Mazarin, as every gentleman ought to be.”

“Hush! don’t let us talk politics, my lord.”

“Then my keeper would begin to trust this man and to depend upon him, and I should have news from those without the prison walls.”

“Ah, yes! but how can the news be brought to you?”

“Nothing easier; in a game of tennis, for example.”

“In a game of tennis?” asked La Ramee, giving more serious attention to the duke’s words.

“Yes; see, I send a ball into the moat; a man is there who picks it up; the ball contains a letter.  Instead of returning the ball to me when I call for it from the top of the wall, he throws me another; that other ball contains a letter.  Thus we have exchanged ideas and no one has seen us do it.”

“The devil it does!  The devil it does!” said La Ramee, scratching his head; “you are in the wrong to tell me that, my lord.  I shall have to watch the men who pick up balls.”

The duke smiled.

“But,” resumed La Ramee, “that is only a way of corresponding.”

“And that is a great deal, it seems to me.”

“But not enough.”

“Pardon me; for instance, I say to my friends, Be on a certain day, on a certain hour, at the other side of the moat with two horses.”

“Well, what then?” La Ramee began to be uneasy; “unless the horses have wings to mount the ramparts and come and fetch you.”

“That’s not needed.  I have,” replied the duke, “a way of descending from the ramparts.”

“What?”

“A rope ladder.”

“Yes, but,” answered La Ramee, trying to laugh, “a ladder of ropes can’t be sent around a ball, like a letter.”

“No, but it may be sent in something else.”

“In something else —­ in something else?  In what?”

“In a pate, for example.”