"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 grat.i.tude. 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 pa.s.sing 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 pa.s.senger 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 a.s.sured 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 pa.s.senger 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 pa.s.sed 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 anch.o.r.ed not far from sh.o.r.e.

"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.

CHAPTER V

THE LADY ON THE VERANDAH

No one was coming; Lady Gardiner dared to turn the key. The door opened, and she looked into the room beyond.

It was a cabin, of the same size as the others, and fitted up as a stateroom, but furnished and decorated differently. The five which Kate had been shown yesterday were comfortable, but not particularly luxurious, and she had wondered, since this was ostensibly a pleasure trip, that beauty-loving Virginia had not thought it worth while to have her own cabin, at least, made more dainty.

In the locked stateroom, whose secret Kate was violating, the berth was hung with old brocaded silk of blue and silver, the curtains edged with curious thick lace, yellowed by time. On the floor lay a beautiful tiger-skin, covering it from end to end. A large fitted travelling-bag stood open on a cushioned seat, showing silver-topped bottles; and the wall on one side of the cabin was almost hidden with photographs and sketches which had been tacked up, over a low book-shelf, filled with volumes in uniform binding of blue and gold. The photographs were of places as well as people, and Kate had just identified the Valley of the Shadow, dominated by the Chateau de la Roche, when a sudden sound sent her out of the cabin and into the saloon, with her heart pounding and her nerves throbbing, in shamed fear of discovery.

She had just time to lock the door and pa.s.s on to that of her own stateroom when Celestine appeared, carrying various small parcels. She had been sent to the yacht by her mistress to finish a few preparations for the voyage, and was surprised to see Lady Gardiner. Kate, however, was prepared with her story of the lost ring, which no doubt Celestine would repeat to Virginia, and produced the jewel, saying that fortunately she had found it on the floor of her cabin.

The maid had no suspicion, probably did not dream that the _Bella Cuba_ had a secret to keep, and Lady Gardiner was rowed back to sh.o.r.e, confident that she had come safely out of the morning's adventure. The mystery, however, remained a mystery, except that Kate was certain now of one thing which she had only suspected. There was to be a pa.s.senger on board the _Bella Cuba_, whose expected presence had carefully been concealed from her. For this pa.s.senger elaborate preparations had been made. Everything behind that locked door was beautiful, but nothing was new. In the fleeting glimpse Kate had obtained before the sound of Celestine's descending steps had sent her flying from her stolen inspection, she had been impressed with the feeling that the decorations of the stateroom had all been taken from some other room, with the view of surrounding its occupant with old a.s.sociations.

Lady Gardiner hoped to see Loria before going back to the hotel, and an appointment had been made, to be kept as nearly to the time as possible; but he was not at Rumpelmayer's, the place of meeting, and, astonished at his defection, she was obliged to return to the Cap Martin without the expected talk. In her room she found a line from the Italian. Sir Roger Broom had seen him at Rumpelmayer's, he explained, and had joined him there. Fearing that Lady Gardiner might come in while they were together, he pleaded an engagement and went out, still accompanied by Broom. Now, Loria asked, was it possible that Miss Beverly's cousin suspected anything? Had Lady Gardiner been imprudent and dropped the slightest hint of their new allegiance?

Kate had begun a note in reply, when Virginia knocked at her door, inquiring whether she were ready for luncheon. "Wait for me just a moment in the sitting-room," said the elder woman, and, her ideas confused in the necessity for haste, she merely scrawled: "Don't think Sir Roger or any one suspects. Must have been an accident. Key worked well. I saw cabin. It is ready for a pa.s.senger. I would wager that that pa.s.senger is Madeleine Dalahaide. Probably we shall not have a word together in private now before we go, but will write you from every port, or wire if necessary and possible.--K. G."

This note she took down to the dining-room with her, and barely had a chance to press it into Loria's palm as he bade her, with the others, a rather formal farewell.

The Marchese was not one of those who went out to the yacht to see the last of the beautiful American girl and her party. Virginia had definitely refused him now, and the old, pleasant intimacy had been brought to a sudden end. Nevertheless, he sent her flowers--a great basket of roses big enough to fill up half of her stateroom on the _Bella Cuba_--which she promptly gave to Kate, with various other elaborate offerings, keeping for her own cabin only a small bunch of fragrant violets sent by some one whose name she seemed to guess, although there was no card.

So, at last, they were off; and no sad-faced girl in black had appeared.

Besides the original party of four, there was only a little dark, keen-eyed English doctor, taken from his practice in Mentone. He looked like a man who would know how to keep a secret, and Kate wondered whether the mystery of the _Bella Cuba_ were a mystery to Dr. Grayle.