"_Mais oui_. It was difficult, but I have brought him to my way of thinking. I am certain that it was an error in the first place not taking you into our confidence. _Eh bien_! Tell me, do you know how your foster-sister came to be in the charge of your mother at the Inn at the Red Oak?"

"Yes, I know what my mother has told me. The child was abandoned to her rather than left in her charge."

"_Mais non_" said Madame de la Fontaine; "General Pointelle was impelled to act as he did by the strongest motives,--nothing less than the tremendous task, undertaken for his country, to liberate the Emperor Napoleon from Elba. General Pointelle was a soldier,--more, he was a marechal of the Empire; the greatest responsibilities devolved upon him.

It was impossible for him to be burdened with a child."

"But why, madame, did he not take my mother into his confidence?"

"Secrecy was imperative, monsieur. Even to this day, you do not know who General Pointelle actually was. His was a name well-known in France, glorious in the annals of the Empire; a name, too, familiar to you in a somewhat different connection. 'General Pointelle' was the _nom-de-guerre_, as it were, of Francois, Marquis de Boisdhyver, marechal de France."

"Francois! you say, _Francois_!" exclaimed Dan.

"_Mais oui_, monsieur; but that should hardly astonish you so much as the fact that he was a Boisdhyver. Why are you surprised?"

"Simply, madame," exclaimed Dan hastily, "by the fact that it is the same name as that of our Marquis."

"Not quite," corrected the lady; "our Marquis--as you say--is Marie-Anne-Timelon-Armand de Boisdhyver, the General's younger brother."

"Ah! and therefore Nancy's uncle?"

"Yes, the uncle of Nancy Frost, or of Eloise de Boisdhyver."

"I see," said Dan. "I begin to see."

"_Eh bien_, monsieur. General Pointelle--the marechal de Boisdhyver,--left the Inn at the Red Oak upon a mission for the Emperor, then at Elba. _Helas_! that mission ended with disaster after the Hundred Days; for, as you know, the Emperor was sent in exile to St. Helena; and, as you may not know, the Marechal de Boisdhyver was killed on the plains of Waterloo. _Allons_; when he left Deal, he concealed in a hidden chamber, which one enters, I believe, from a room you call the Oak Parlour, a large treasure, of jewels and gold. This treasure, saved from the _debacle_ in France, he had brought with him to America, and he hid it in the Inn, for the future of his little daughter Eloise. You remember that your mother was to hear something of advantage to her and the child, did not the General return. It was the secret of the treasure and the directions to find it. Well, Monsieur, at Waterloo, you must know, the Marechal and his brother, the present Marquis, fought side by side.

Francois de Boisdhyver fell, n.o.bly fighting for the glory of France; Marie-Anne had the good fortune to preserve his life, but was taken prisoner by the English. Before the Marechal received his death wound, the two brothers spoke with each other for the last time. In that moment, monsieur, the Marquis Francois revealed to the Marquis Marie-Anne that he had abandoned his daughter in America and that he had concealed in your old inn a treasure sufficient to provide for her future. He charged his brother to go to America, if he survived the battle; claim the little Eloise; rescue the treasure, and return with her to France and restore the fallen fortunes of the House of Boisdhyver.

"It took the Marquis Marie-Anne a long time to carry out his brother's dying injunctions," said Dan.

"Ah! but yes. You do not realize that the Marquis Marie-Anne, after the fall of Napoleon, spent many years in a military prison in England, for I have already told you that he fell into the hands of the enemy on the field of Waterloo. When at last he was released, he was aged, broken, and in poverty. His brother, in those dreadful moments on the battlefield, had been able to give him but the briefest description of the Inn at the Red Oak and the hidden treasure. He did not tell him where the treasure was, but only how he might obtain the paper of instructions which the Marechal had concealed in a curiously-carved old cabinet in the Oak Parlour. The Marechal, monsieur, loved the mysterious, and chose the device of tearing into two parts this paper of directions and concealing them in different hiding-places of the cabinet. Those directions, after many years, grew vague in the younger brother's memory.

"_Eh bien_, the Marquis was at last able to make the journey to this country. You must remember he had nothing wherewith to prove his story, if he gave you his confidence at once; and so, he decided, to investigate quietly alone. But he won the confidence of Mademoiselle Nancy,--that is, of his niece, Eloise de Boisdhyver,--and revealed to her the secret of her ident.i.ty and the mysterious story of the treasure. You follow me in all this, Monsieur Dan?"

"Perfectly, madame," Frost replied. "But as yet you have told me nothing of your own connection with this strange history."

"Pardon, dear boy," rejoined Madame de la Fontaine; "I was about to do so, but there is so much to tell. My own connection with the affair is quite simple. I am an old friend, one of the oldest, of Monsieur le Marquis de Boisdhyver, and, when I was a very young girl, I knew the Marechal himself. It has been my happiness to be able to prove my friendship for a n.o.ble and a fallen family. One day last summer, Monsieur de Boisdhyver told me his brother's dying words, and it was I, Monsieur Dan, who was able to give the money for this strange expedition. The poor Marquis had lost quite all his fortune."

"I understand," said Frost. "But, yet, madame, I do not see the necessity for the secrecy, the mystery, for these strange signals at night, for these midnight investigations, for this schooner and its rough crew, for Nancy's disappearance, for my own imprisonment here."

"Please, please," murmured Madame de la Fontaine, as she held up her hands in smiling protest. "You go too fast for me. _Un moment, mon ami, un moment_. It was sixteen years ago that the Marechal de Boisdhyver was a guest at the Inn at the Red Oak. You forget that the Marquis de Boisdhyver had no proof of his right to the treasure, save his own story, save his account of his brother's instructions on the field of Waterloo.

By telling all he might have awakened deeper suspicions than by secrecy."

"That, I must say," Dan interrupted, "would hardly be possible."

"So!" exclaimed Madame de la Fontaine, with an accent of displeasure.

"_Ecoutez_! Monsieur le Marquis was to come a month in advance, as he did come; take up his quarters at the Inn; reconnoitre the ground; and win, if possible, the confidence and aid of mademoiselle. He fortunately succeeded in this last, for he found it otherwise impossible to enter into the old wing of the Inn and examine the Oak Parlour. With the a.s.sistance of Eloise, this was accomplished at last, and the paper of directions was found; at least, found in part.

"Then I, having impressed the services of Captain Bonhomme and his ship the _Southern Cross_, set sail and arrived at the House on the Dunes only a few days ago, as you already know. The signals that you saw flashing at night were to indicate that all was well."

"The green light, I suppose," commented Dan, "was to indicate that; and the red--"

"Was the signal of danger. Because the Marquis discovered last night that you were not in the house; he flashed the warning that made Captain Bonhomme go to the House on the Dunes. Quite recently the manners of your friend, Mr.--eh--?"

"Pembroke?"

"Yes, Mr. Pembroke--led the Marquis to believe that he was being watched.

"I understand," said Dan, "but nothing you have told me so far, madame, accounts for Nancy's disappearance, and I am as anxious as ever to know where she is."

"Mademoiselle is perfectly safe, Monsieur Dan; I a.s.sure you. She left the Inn because she had fear of betraying our plans, particularly as she loved your friend, Mr. Pembroke."

"It is still strange to me, madame, that Nancy should distrust her oldest and best friends. But now you will let me see her?"

"Of course I shall soon, very soon, my dear boy. I have told you all, and now you will aid me to find the treasure that is your foster-sister's heritage, will you not?"

"Why certainly I want Nancy to have what is hers," replied Dan.

"Bravo, my friend. We are to count you one of us, I am sure."

"Just a moment," said Dan, resisting the temptation to touch the little hand that had been placed impulsively upon his arm. "May I ask one more question?"

"A thousand, my dear, if you desire."

"Why then, since until last night everything has gone as you planned it, why has not the treasure already been discovered?"

"Because, _mon ami_; the Marquis has only been able to visit the Oak Parlour at night. And also it was decided to wait until I arrived."

"With the schooner?" suggested Dan.

"With the schooner, if you will. And you may remember that it was only the day before yesterday that I reached your so hospitable countryside."

"Ah! I understand; so then all that you desire of me, madame, is that I shall permit the Marquis or anyone else whom you may select for the purpose, to make such investigation of the Oak Parlour as is desired."

"Yes, my friend; and also there is yet another thing that we desire."

"But suppose, madame, that I cannot agree to that?"

"Ah! _cher ami_, but you will. I confess--you must remember that the Marquis de Boisdhyver has been a soldier--that my friends have not agreed with me entirely. It has seemed to them simpler that we should keep you a prisoner on this ship, as we could so easily do, until our mission is accomplished. But,--I like you too much to agree to that."

Dan flushed a trifle, but he was not yet quite sure enough to fall in entirely with his charming gaoler's suggestions. "Madame de la Fontaine,"

he said after a moment's reflection, "I am greatly obliged to you for explaining the situation to me so fully. I shall be only too happy to help you, particularly in anything that is for the benefit of Nancy."

"I was sure of it. Now, my friend, there is a service that you can immediately render."

"And that is?" asked Dan.

"To entrust to me the other half of the paper of directions written by Francois de Boisdhyver, which you found in a secret cubby-hole in the old cabinet."