“But you can sleep when you please, monsieur?” said Morrel.

“Yes.”

“You have a recipe for it?”

“An infallible one.”

“That would be invaluable to us in Africa, who have not always any food to eat, and rarely anything to drink.”

“Yes,” said Monte Cristo; “but, unfortunately, a recipe excellent for a man like myself would be very dangerous applied to an army, which might not awake when it was needed.”

“May we inquire what is this recipe?” asked Debray.