Kitty looked at him in silence with flashing eyes, and then laughed bitterly.

"And how long is it since you added the spy business to your usual work?" she asked, with a sneer on her colourless face.

"Since a few moments ago," replied Naball coolly. "I came to see you on business, and, hearing you in conversation with a lady, did not like to interrupt till you were disengaged."

"I'm very much obliged to you for your courtesy," said Caprice scornfully; "but now you have satisfied your curiosity. M. le Mouchard, I'll trouble you to take yourself off."

"Certainly, after I've had a few moments' conversation with you."

"I decline to listen," said Kitty haughtily.

"I think you had better," observed Naball significantly, "as it's about the robbery of your jewels."

"I forbade you to go on any further with that matter."

"You did; but I disobeyed your injunction."

"So I understand," replied Kitty indignantly; "and may I ask if you have discovered anything?"

"Yes--this!" and he showed the diamond crescent to Caprice. She started violently, and her pale face flushed a deep red.

"Where did you get it?" she asked.

"From Randolph Villiers."

"Villiers!" she echoed in surprise. "How did it come into his possession?"

"That is what I want to discover."

"Then you may save yourself the trouble, for you will never know."

"I understand that," said Naball quietly; "nothing can be done unless you permit me to go on."

"I forbid you to go on," she retorted angrily.

Naball bowed.

"Very well," he said quietly, "then there is nothing for me but to leave."

"No, I don't think there is," assented Kitty coldly, turning to re-enter the house.

"But, before I go," went on the detective, playing his great card, "I will leave your jewel with you."

"That," said Kitty, glancing over her shoulder at the crescent--"that is not mine."

"Mr. Fenton says it is."

"Mr. Fenton!" echoed Caprice jeeringly; "and how does Mr. Fenton know?"

"I should think he was the best person to know," retorted Naball, nettled at her mockery.

"A good many people think the same way," said Kitty disdainfully, "but in this case Mr. Fenton is wrong--I never saw those diamonds before."

"Then how did it come into Mr. Villiers' possession?"

"I don't know, not being in Mr. Villiers' confidence."

"Oh!" said Naball significantly, "you are quite certain you are not?"

"I don't understand you," replied Kitty coldly; "explain yourself."

"Certainly, if you wish it," said the detective smoothly. "I will tell it in the form of a little story--have I your permission to be seated?"

She nodded carelessly, whereupon Naball sat down on one of the lounging chairs, and, crossing his legs, settled himself composedly, while Kitty, standing near him with loosely-clasped hands, looked idly at the green lawn, with its brilliant border of many-coloured flowers.

"There was once a woman called Folly, who lived--let us say--in Cloudland--" began Naball airily.

"Rubbish!" said Kitty angrily.

"Nothing of the sort," retorted Naball coolly, "it is truth in disguise. I have been to school--I have read Spenser's 'Faery Queen'--if you please, we will consider this story, though not in verse, as one of the lost cantos of the poem."

Kitty shrugged her shoulders with contempt. "I think you're mad," she said coldly. "Perhaps I am," retorted Naball sharply, "but there's method in my madness, as you will soon find out--so, to go on with the lost canto of the 'Faery Queen.' This woman, Folly, was reputed to have a hard heart--no doubt she had, but there was one soft spot in it--love for her child. Many men loved this charming Folly, and paid dearly for the privilege. One man, misnamed Strength, loved her madly, and gave her many jewels. Strength had a friend, called Weakness, and though they were so dissimilar in character, they worked together. Weakness also loved Folly, though he had a wife, and, to gain Folly's love, he stole a lot of money. His wife discovered this, and going to Folly, implored her to help Weakness, but in vain, till at last she gained her point by appealing to the one soft spot in Folly's heart--love for her child. She was successful, and Folly promised to save the husband by replacing the money, which she could do through the agency of Strength, who was her lover.

"Folly, however, did not know where to get the money, so, in despair, determined to part with her jewels. She dared not do so openly, lest the inhabitants of Cloudland should find out what Weakness had done, so she enlisted the services of a man called Vice. Here," said Naball gaily, "we will leave the narrative style, and finish the story dramatically."

Kitty, who had grown pale, made no sign, so Naball resumed.

"Scene, a supper-room, with a window open--time, night--supper ended--guests away--enter Vice through open window--helps himself to champagne. Folly, informed of presence of Vice, enters the room and orders him out--he refuses to leave till he gets money--she refuses to give it to him. Suddenly an idea strikes her, and she tells Vice she will give him money if he sells her jewels for her secretly--Vice consents. Folly goes up to her room, gets jewels, gives them to Vice, who goes away and breaks down shrubs under window, which is opened by Folly to show every one that a burglar has stolen the jewels. Rumours of the theft get about--Bloodhound goes on the track--traces Vice to his den--finds one jewel--comes to show it to Folly--overhears wife of Weakness thanking Folly for replacing money stolen by her husband--exit wife of Weakness--enter Bloodhound to Folly, who denies having ever seen jewel before. Bloodhound tells a story to Folly, which Folly--"

"Denies, yes,............