The Marchese Loria ordered tea, and the two newly made allies pretended to have no important more business than eating and drinking. But certain that nobody was within hearing distance, Loria squandered little time in frivolities. At any moment some one they knew might come in and interrupt their talk.

"You said that I looked 'very down,'" he began abruptly. "That is cool English for broken-hearted, no doubt. I'm half mad, I think, Lady Gardiner. For four nights I haven't slept; for three days I've scarcely eaten. You know why; there's no use in wasting words on explanation."

"You love her so much?" exclaimed Kate.

"I love her so much. You believe me?"

"Yes; for you have the reputation of being a rich man, and it can't be all a bubble, or you wouldn't buy eighty-pound presents—for gratitude, and rather premature gratitude at that."

"Ah! the gift hasn't been made yet."

"I fancy it will be made. And the principle is the same. You can't be a fortune-hunter, like many agreeable, titled countrymen of yours whom I have met."

"If a man began by seeking out Miss Beverly as a fortune-hunter, he would end by being her lover. She is the most beautiful girl on earth, and—the most maddening. I think I shall go mad if I am to lose her."

"How you Italians can love—and hate!"

"Yes, we can hate also, it is true. There is no half-way with us. Lady Gardiner, I used to think that you disliked me; but to-day you are different. I was as desperately in need of help as a drowning man, and I caught at the new look of kindness in your eyes, as such a man catches at a floating spar."

"Perhaps it was the appeal in your eyes that called out the answer in mine," said Kate, half believing that she told the truth; for there was a certain magnetic power in the man's passion, which was, at least, sincere. "What help can I give you?"

"First of all, you can answer a few questions. What have I done to change Miss Beverly so completely?"

"Frankly, I don't know. There's something odd going on—something which interests her so much that she can think of nothing else."

"The change began on the day of—our ride. Our last ride! The last of everything worth having, it has been for me. She was angry because I was unwilling to go into—that valley. But afterward, when she learned how intimately I had been associated with the people at the chÂteau there, how could she blame me? I suppose she did learn the story?"

"She learned something of it, I know, the night after we rode up the valley. You remember there was a dance? I had left my fan in our sitting-room, and ran up to find it. There was no light in the room, and Virginia and Sir Roger were on the balcony. Of course, I didn't mean to listen, but I couldn't find the fan at first, and I didn't like to startle them by suddenly switching on the light, so I—er—I overheard a little of the conversation. Sir Roger was telling her the story of that unfortunate Maxime Dalahaide—why, Marchese, how you must have loved him! The very mention of his name turns you pale."

"We were like brothers," said Loria in a low voice. "But go on. Did Sir Roger Broom mention me in connection with the story?"

"Yes."

"The scoundrel! That explains all, then. This is your honourable English gentleman, who traduces a man behind his back, to ruin him with the girl they both love!"

"You do Roger Broom injustice. He defended you. Virginia thought that your friendship was not worth much, since you believed Maxime Dalahaide guilty, but Sir Roger assured her you had behaved exceedingly well."

"H'm! One knows what faint praise can do. Did he give her all the details of that loathsome story?"

"No; he refused. I was rather sorry, as I was interested by that time. Besides, I had wanted to know, and I couldn't think of any one it would be convenient to ask, except Sir Roger or you."

"I wish he had told her all! If he had, she would never have wished to hear of the Dalahaides again."

"You speak bitterly of your old friends."

"I? No, you misunderstand. I mean only that a girl—a stranger—would be horrified if she could know the full details. It was a ghastly affair. I loved Max, but there was no excuse for him—none. And it would be better for Miss Beverly to have nothing to do with that family. They bring unhappiness to all who come near them. It is as if they were under a curse, which every one connected with them must share. I can't bear to think that so black a shadow should darken her sunlight. Already, you see, she has changed. She goes once to the ChÂteau de la Roche, and the spell falls upon her."

"I'm not sure that she hasn't been more than once," said Lady Gardiner.

"Ah! that was one of the things I wished to ask. You think so?"

"I don't know. The morning after we all went there she disappeared for hours, and would say nothing except that she had slept badly, got up early, and gone off for a ride. Whether Mr. Trent was with her or not I can't tell but when I first saw her, after looking everywhere, they were together, so absorbed in what they were saying that I believe if a revolver had been fired within a dozen yards of them they would hardly have heard it. At luncheon that same day, Sir Roger was telling me how he had seen the agent, and found out about the chÂteau, as it appears she had asked him to do—she has but to ask and to have, with him, you must know!—and though she was pleased and interested to a certain extent, still, she seemed to be thinking of something else."

"That something else! If I could find out what that was, I might know who is taking her from me."

"I'm afraid it's not as simple an affair to unravel as that; for I can tell you one of the things, at least, which was apparently occupying her thoughts at the time, yet I can't quite see why or how it could have much to do with you. You remember, perhaps, that you came while we were at luncheon the day after our ride into the Valley of the Shadow, and proposed that we should all go to Monte Carlo on your motor-car, that we should spend the afternoon in the Casino, and dine with you at the HÔtel de Paris? Virginia said that she had important letters to write, and couldn't go; and her manner was rather distant."

"It chilled my heart."

"Well, she asked Sir Roger and Mr. Trent to come up to her sitting-room after luncheon. Naturally, I was there too; I've been told to look upon the room as my own. She did not tell what she had been doing in the morning, but, wherever she had been, she had contrived to discover a good deal more about the Dalahaide story than Sir Roger had been willing to tell her the night before, and she announced boldly, that in spite of everything, she believed Maxime Dalahaide was innocent. She demanded of Roger—who has spent a good deal of time in France, you know, and is supposed to be well up in French law—whether it wouldn't be possible to have the case brought up again, with the best lawyers in the country, expense to be no object. When Roger had shown her that the thing couldn't be done, and there was no use discussing it, she wanted him to say that by setting some wonderful detectives on the trail of the real criminal the truth might be discovered, and the man unjustly accused brought home in triumph from Noumea by a penitent Government. Sir Roger assured her that was hopeless. That, in the first place, Maxime Dalahaide wasn't innocent, and that, in the second place, even if he were, his innocence would be still more impossible to prove after all these years than it would have been at the time of the trial."

"What did she reply to that?"

"Nothing. She was silent and seemed impressed. She became very thoughtful. Since then I have not heard her say one word of the Dalahaides, except incidentally about the chÂteau, which she actually means to buy, and have restored in time to come to it, if she likes, next year. Now, I don't see why her interest in the Dalahaides, if she continues to feel it, should interfere with her friendship for you."

Loria did not answer. He sat thinking intently, his dark eyes staring unseeingly out of the window. At last he spoke. "Why—why should she interest herself in this cold-blooded murderer, whose best friends turned from him in horror at his crime? Is it pure philanthropy? Has the sister implored Miss Beverly to throw her money into this bottomless gulf? What happened when you were at the chÂteau that day I never knew."

"We thought that the subject was disagreeable to you," said Kate. "We saw and spoke with Miss Dalahaide, a pale, cold girl, dressed in black, with a voice that somehow sounded—dead. She did not mention her brother, and seemed so reserved that I should think it would be difficult to break the ice with her. Indeed, she appeared very annoyed at the necessity for showing us a little room with a life-size picture in it, which I fancied must be a portrait of the brother."

A curious shiver passed through Loria's body.

"Miss Beverly saw that portrait?" he asked in a low, strained voice.

"Yes, and I noticed that she kept glancing at it again and again while we stopped in the room. I suppose a morbid sort of curiosity regarding a murderer is natural, even in a young girl, provided his personality is interesting."

Once more Loria remained silent, his face set in hard lines.

"Such a man as Maxime Dalahaide must have been before his fall, would be a dangerous rival," Lady Gardiner went on, with a spice of malice. She was watching Loria as she spoke, and thrilled a little at the look in his eyes as he turned them upon her. "Oh, these Italians!" she thought. "They are so emotional that they frighten one. Their passions are like caged tigers, and you never quite know whether the cage door is safely locked."

"Maxime Dalahaide will never be dangerous to any man again on this earth—not even to himself, since the worst has happened to him that can happen," answered Loria.

"Strange if, although he is buried in a prison-land at the other end of the world, he might still, in a vague, dim way, be a rival to fear more than another," Kate reflected dreamily. Aloud she went on: "It seems ridiculous to say so, but I believe that Virginia is making a hero of him. She has never seen this man—she never can see him; yet his image—evolved from that portrait at the chÂteau which was his old home—may blur others nearer to her."

"Great heavens! You believe that?"

"I merely suggest it. The idea only occurred to me at this moment. But Virginia is certainly thinking of Maxime Dalahaide. To-day, she was reading a French book about Noumea. She hid it when I came into the room; but later I came across it by accident. Yes, she is thinking of him, but it is only a girl's foolish, romantic fancy, of course—a spoilt child, crying for the moon, because it's the one thing that no adoring person can get for her. I shouldn't worry about it much, if I were you. Indeed, perhaps she sees herself that she is not very wise, and wants to forget. Now she has set her heart on a yachting trip; but you must not speak of it to her or the others, for she asked me not to tell."

"She gives me little enough chance to speak of anything. A short time ago she would not have cared for a yachting trip, unless I were to be of the party. Now, I suppose, her wish is to be rid of me."

"Her wish is also to be rid of me."

"You are not to go?"

"Not if Virginia can make a decent excuse to leave me behind."

"Who, then, goes with her?"

"Her half-brother, and Sir Roger Broom. She isn't even going to take a maid."

"Heavens! It is Sir Roger Broom, then, who will win her!"

"I don't know what to think. She has refused him; he is many years older than she, and she has known him since she was a child, for Sir Roger went often to America while her father—his cousin—was alive. Why should she suddenly make up her mind to marry him? He was her guardian during her minority, or what remained of it after her father's death; now she has had her one-and-twentieth birthday, and is her own mistress. I fancied that she intended to remain so for a time, unless she lost her head—or her heart—and Sir Roger, nice as he is, is scarcely the man to make a girl like Virginia Beverly do either. Still, I don't understand the yachting trip. It is in every way mysterious; and since you have asked my advice, it is this: find out where they are going, and appear there, as if by chance. By that time our spoiled beauty's mind may have changed."

"Won't you tell me where they are going?"

"I would if I could." This was true, since Kate was sure that, change as Virginia might, she would never return to her brief, ballroom fancy for the Italian. "I hinted at Naples, Greece, and Egypt, and Virginia answered that it would be 'something of the sort'—answered evasively, saying nothing was decided yet; and so the conversation would have ended if George Trent hadn't come bursting in, very excited, exclaiming before he saw me that he'd got hold of exactly the right steam yacht, with four cannon."

Loria started like a sensitive woman. "A yacht with four cannon! What can they want with cannon?"

"I asked if they were fitting out for pirates, and Mr. Trent assured me that the cannon being on board was a mere accident; they would not have them removed, but they had no intention of making use of them. Still, there's no doubt that there's some mystery behind this yachting expedition. I can't make it out at all. Whether it is Mr. Trent's plan——"

"But he would not wish to go without you."

"A few days ago, perhaps not. But others besides Virginia have changed. That day when we rode up the Valley of the Shadow, as they call it, was destined to be an eventful day for us all."

"You mean——"

"I mean that George Trent is a different man since he went to the ChÂteau de la Roche."

A dark flush rose to Loria's forehead. "He met Madeleine Dalahaide?"

"One might think, from your expression and accent, that you were jealous."

"One would think wrongly then. A man can't be in love with two women at the same time."

"Can't he? I wasn't sure. Men are strange; perhaps there's something of the dog in the manger about them, at times. At all events, George Trent is much interested in the yachting trip, and he doesn't want me to go. Perhaps Miss Dalahaide is to be of the party; and in that case I should be the odd woman. Not that it matters to me. George was pleasant to flirt with but I should not marry again, unless I married money. Virginia's great fortune comes from her father, George's step-father, who was jealous of the mother's affection for the first husband's son, and disliked him. George will accept nothing from Virginia, and has only what his mother could leave him—a miserable five thousand dollars a year."

Loria scarcely listened. His level black brows were drawn together. "She was reading a book about Noumea," he said slowly. "What if—no, it is impossible—impossible!"

"What is impossible? If I am to help you, you must have no secrets from me."

"She could not hope, if she went there, to see him. Bah! The bare thought is monstrous."

"It is a little far-fetched," said Kate. "I should think the adventure they are undertaking will be no more startling than an attempt to reach the Second Cataract. The cannon might be needed there, you know."

"That is true. But, Lady Gardiner, you must find out where they are going, and let me know. A hundred diamond serpents would not be enough to testify my gratitude. You mean to go with them?"

"If they will take me."

"They must take you. They must! You are my only hope, the only link that will be left between me and Virginia Beverly. Listen! We are talking frankly to each other, you and I. We never thought to be such friends—but we are friends, and must trust each other to succeed. You often speak, half-jestingly, of being poor. I have money—I don't say enough; who has enough? But I am not a poor man. Watch Virginia for me; watch Sir Roger Broom. Let me know where this yacht is taking you, whom she carries, all that happens on board of her. Advise me, from what you see of passing events; and for all these services, worth an inestimable sum to me, I will give you what I can afford—say, a thousand pounds. You shall have half down the day you start, and the other half the day that you return."

"You are generous; and—I will be loyal," said Kate. "It will not be my fault, I promise you, if the yacht sails without me. Now I must go. We must have been talking here for more than an hour, for Virginia's carriage, which she lent me, has just driven up to the door. Whenever there is a new development of this mystery, which interests us both, you shall know it. I wish I could take you up to Cap Martin with me, if you are ready to go that way, but perhaps it would be wiser not—especially as the victoria isn't my own."

Kate Gardiner had not been in the hotel an hour when a box was brought to her door by the Marchese Loria's valet. Inside was the diamond serpent. She told herself that she had done a very good afternoon's work.

Soon every one knew that the American heiress and beauty, Miss Virginia Beverly, had bought, for twenty thousand pounds, the famous steam yacht which the mad Spanish Prince d'Almidares had used as a despatch boat at the time of the American war with Spain. For some time it had been for sale, lying in harbour at Nice; but it had been too costly a toy; the cannon with which it was armed were worth only the price of old iron to most buyers of yachts. They were equally useless to Miss Beverly and her party, as she and George Trent and Roger Broom impressed upon all who asked questions; but, then, what was the use in wasting time enough to dismantle the yacht, as she was wanted immediately, and the cannon were too cleverly concealed to injure the smart appearance of the little craft?

It was given out that the Bella Cuba would touch at Greece, go on to Egypt, and perhaps visit Algiers and Lisbon, steaming at last up the Thames to Tilbury. Virginia Beverly ostentatiously bought thin summer clothing, saying that it would be summer weather on the sea before she bade good-bye to the water. Still, Virginia announced that she did not wish to be bound down to a definite programme, and Kate Gardiner had to be satisfied with a prospect of vagueness if she intended to be of the party.

Not for a single moment had she abandoned that intention. Even if she had not stood to earn a thousand pounds she would have moved heaven and earth to go, for more and more, as the days of preparation went on, her curiosity and excitement increased.

Roger Broom, it was clear, had been intensely annoyed when he was informed that Lady Gardiner had so far overcome her fear of the sea, as to wish to be a passenger on the Bella Cuba. He had said little, but his face was expressive, and Kate was of opinion that he would have said a great deal more, had not some strong motive restrained him. Perhaps, she thought, this motive was fear of rousing her suspicions if he too emphatically advocated her stopping behind. But—suspicions of what? That was the question she often asked herself, and could never answer.

She had asked it of Loria also, when they met—as secretly as if the bond between them had been a forbidden love. But if the truth about the yachting trip had been told, even he had no solution ready for the puzzle.

At last the yacht, which had been re-painted, was ready, the captain and crew of picked men, all Englishmen, were engaged, and the Bella Cuba steamed into the harbour at Mentone, exactly one month from the date (as Kate happened to remember) of the eventful ride into the Valley of the Shadow.

They were to start in two days, and Lady Gardiner's heart sank at the thought of all the physical suffering she was doomed to endure. Nevertheless, when Virginia hinted that, if she chose to think better of her decision, it was not yet too late, she courageously assured the girl that she was looking forward to the trip. She had always wanted to see Egypt!

The yacht was swift, and had proved herself seaworthy, but she was comparatively small, and when Kate went on board with Virginia to inspect the accommodation, she was surprised to be shown only five passenger cabins. Still, as she had been informed that there were to be but four in the party, she did not see why it would be impossible for Virginia's maid to go, and ventured to say as much.

"But we have decided to take a doctor," explained Virginia. "We shall be so long at sea that otherwise it really wouldn't be safe."

"For my part I'd much rather have a maid than a doctor," sighed Kate, to whom Virginia's Celestine had made herself agreeably useful. "We shall have nothing worse the matter with us than seasickness; and how are we to do our hair?"

Thus bemoaning her fate, she passed along the line of white and gold painted doors, and stopped suddenly at a sixth, the only one which was closed. Gently she tried the handle. It did not yield.

"One would think that this ought to be another cabin," she remarked sweetly; "else what becomes of the symmetry? Now, if only it were one, you might take Celestine. You'd be so much more comfortable."

"That cabin can't be used," Virginia said, her eyes very bright, her cheeks very red. "And if you want Celestine, Kate, you must stop on land."

Lady Gardiner at once protested that she was not thinking of herself; oh, indeed no! but merely of her dear girl, who was not used to being her own maid. She said no more of the locked door, but she could think of nothing else. Why could the cabin not be used, and why had Virginia suddenly grown cross at the bare suggestion that it should be? Was it possible that Madeleine Dalahaide was going after all, that her presence was to be kept secret from Kate until the last moment, and that she was to have this stateroom? Perhaps, Lady Gardiner's jealous suspicion whispered, she was already in the cabin, and had locked herself in, fearing just such an intrusion as the turned key had prevented.

That night she saw Loria, and told him precisely what had happened on board. "I shouldn't wonder," she said reflectively, "if the whole mystery of this trip were not on the other side of that closed door. Something tells me it is so."

"When do you start?" asked the Italian.

"To-morrow, at five in the afternoon."

"Could you make an excuse to go on board in the morning alone?"

"Yes. Celestine has taken most of our things on to-day, and put them away for us. We are not supposed to leave the hotel till three o'clock. But I could say I had lost something, and hoped that I'd left it on the Bella Cuba. Or perhaps I could slip on board without saying anything until afterward. But what good would it do me? The door isn't likely to be unlocked; and I can see nothing through the keyhole. I tried this afternoon."

"I will get you a key which, if there isn't one already on the inside, will open the door."

In the night Kate Gardiner had strange dreams of the locked cabin. Twenty times in her sleep she was on the point of finding out the secret, but always woke before she had made it her own. She was up early in the morning, and went out, saying, as if carelessly, to Celestine, that she must buy a few last things which she had forgotten. In the town she met Loria, as they had arranged over-night, and he put into her hand something in a sealed envelope.

"You are sure this will do it?" she asked.

"Sure," returned the Italian.

Then they parted; Kate took a small boat and was rowed out to the Bella Cuba, which lay anchored not far from shore.

"I have come on board to look for a diamond ring which I think I dropped in my cabin yesterday," she remarked to the captain.

He turned away, all unsuspicious and Kate hurried to the saloon off which the cabins opened. Already she had broken the seal on the envelope, and taken out a small, peculiarly shaped steel implement. With a quick glance over her shoulder and a loud beating of the heart, she thrust the master-key into the lock of the closed door.