As was natural after so restless a night, Hayden slept late the next morning, but when he awoke it was with his usual sense of buoyant optimism. The forebodings of the night had vanished, and the good, glad, fat years stretched before him in an unclouded vista. To-day in all probability marked the conclusion of his comparatively lean years. A half an hour of conversation with those mysterious "owners," the disclosure of his maps, photographs, ore samples, the report of the assayers, etc., and then, the final arrangements. It might result in a trip to the property; but a journey made, his high heart promised, with Marcia.

At the thought of her a slight cloud obscured the shining towers of his Spanish castles. He recalled with a pang her pallor, her agitation of the night before. Something had evidently lain heavily upon her mind; she had been greatly distressed, even alarmed; but with the confidence of a lover he saw himself a god of the machine, consoling, reassuring, dissipating grief, and causing smiles to take the place of tears.

Upheld by these pleasant reflections, he breakfasted and then strolled through the rooms. They had been put in perfect order. And with the exception of the orchids, now sedately arranged in bowls and vases, instead of fluttering from palm-trees and lattices, there was no trace of the last night's festivities. Suddenly he bethought himself of getting together his photographs, etc., in readiness for the interview of the afternoon; but they were no longer on the small table between the drawing-room windows, where he had placed them the night before.

After seeking for them in every likely place for a few moments, Hayden rather impatiently summoned Tatsu and demanded to know what he had done with them. Tatsu, however, was a picture of the grieved ignorance he professed. He said that after every one had left the apartment, the night before, he had locked up very carefully and gone to bed; that he had arisen early in the morning, shortly after five, and had put the rooms in their present and complete order; and he was positive that there were no photographs upon the table then.

Hayden questioned him closely about the extra servants taken on for the occasion; but he insisted that none of them had penetrated farther than the dining-room, and that he, himself had seen them all leave before the departure of the guests.

"There is a possibility that I may have tucked them away somewhere and have forgotten about them," said Hayden half-heartedly. "Come, Tatsu, let us get to work and make a systematic search for them. Don't overlook any possible nook or cranny into which they may inadvertently have been thrown."

The two of them, master and man, made a diligent and careful search, taking perhaps an hour, but not a trace of the lost package could they find; then, dazed, puzzled beyond words, unbelieving still, but with a heavy sinking of the heart, Hayden sat down to face the situation, to make some attempt to review it calmly and to get matters clear in his own mind.

Their recent search eliminated himself from the situation; reluctantly he relinquished the hope that in an absent-minded moment he had disposed of his precious bundle in some out-of-the-way place. No, he and Tatsu had sought too thoroughly for that to remain a possibility. Eliminating then himself, there remained Tatsu. Although perfectly convinced in his own mind of his valet's innocence, still, for the purposes of inquiry, he would presume him to be the thief. Of course nothing could have been easier than for him to purloin the photographs; but what reason would he have for doing so? The motive, where would be the motive? Would not the reasonable hypothesis be that the Japanese had been approached by some of the owners of the property, who either fearing or suspecting that he, Hayden, held visible proofs of the lost mine, had bribed his servant to gain the desired information? But admitting this to be the case, and Hayden did not believe it for a moment, why had Tatsu remained instead of departing as prudence would seem to dictate?

That of course could be explained by assuming that prudence dictated another line of policy, that he deemed it the best way of averting suspicion. Perhaps! But the conclusion was not particularly satisfactory. Every lead Robert had followed seemed to bring him to a blind wall. He rose restlessly and walked up and down the room, and then sat down again, drumming drearily on the arm of his chair. What now? What new line could he follow? By eliminating the servants, Tatsu, and himself, what remained? His guests. He felt a swift recoil at the bare suggestion, even though a mental and hidden one, of implicating them in this matter, and experienced a succeeding disgust and impulse to abandon his inquiry at once.

Yet, there were the facts, the ugly, inexplicable facts staring him in the face, and he knew that it would be impossible for him to abandon the matter, mentally at least, until he had arrived at some sort of a satisfactory solution. His guests, he ran them over. In every instance, even if they were capable of such an act, the motive was lacking, save in one case. Steadily as the needle veers to the pole, his suspicions pointed to the Mariposa. There at least the motive was not lacking.

Ah, he reflected, falling into deeper gloom, if she had them, then he was indeed lost. Even now, by this time, there would be a set of duplicate photographs made, and careful copies of his charts and maps. In some peculiar way he would probably find the photographs again on his table, and all further communication with him on the subject of The Veiled Mariposa would doubtless be declined by the owners of the property, their voice being Mademoiselle Mariposa. Within the shortest possible time, one of their prospectors on the property would discover the hidden trail, and the owners would begin immediate operations, and he as much out of all transactions as if he did not exist.

Suppose he put a detective on the case immediately; it was extremely likely that before the man could take any steps in the matter or decide on the line he meant to follow, the photographs would again be in Hayden's possession.

No, he thought in bitter cynicism, he might as well await their return with what calmness he could muster, for he saw little or no use in taking any definite steps in the matter.

For a time he remained sunk in a listless dejection, sitting among the ashes of his hopes, his dreams of vast wealth gone, his shining Spanish castles in ruins about him. But again his dulled brain began to work. How did Ydo secure the photographs, if indeed it were she who had secured them? She had come late, laid aside her wraps in the dressing-room, and had entered the drawing-room followed by her secretary. From the moment of her first appearance he remembered practically every motion she had made. She had not moved about at all during her brief stay and had certainly not been anywhere near the table which had held the photographs, but had seated herself and gone through her tricks on the opposite side of the room.

Now as to the secretary. Well, she on her part had not moved from the piano-stool. He could see her, too, enter the room and leave it. The whole mental picture of the group was portrayed before him. As he distinctly remembered, the person who stood nearest the table while Mademoiselle Mariposa drew aside the veil of the future, was Edith Symmes, who sat almost directly before it. To the left of her was Marcia, pale and sad, and close beside her Horace Penfield. Heavens! He jumped impatiently to his feet. He was simply getting into a morbid muddle sitting here brooding over this matter. He must have action, action of some kind, and obeying a sudden impulse, he decided to see Ydo at once.

Wasting no time in reflection, he telephoned to her apartment, and impressed upon the surprised and reluctant maid that no matter who was there, or what the appointments for the day might be, he must see her mistress within the half-hour on business of the most imperative nature.

His rapid and excited speech must have impressed the young woman with the urgency of the case, for she presently returned to the telephone with the message that if he would call within the next twenty minutes Mademoiselle Mariposa would see him.

It is needless to say that Hayden lost no time in getting to the Mariposa's apartment-house, but reached it as fast as a chauffeur could be induced to make the run thither, and was, after a very brief delay, admitted to Ydo's library. She was sitting there alone, looking over a newspaper, and as he came through the door she sprang up smilingly and expectantly to meet him. Then at the sight of his pale and harassed face she recoiled in evident and unsimulated surprise.

"Why, what is the matter?" she cried. "You have aged a thousand years!"

"Matter enough!" he exclaimed. "The photographs and maps of The Veiled Mariposa are all, all gone. They have been taken." He shot the words at her as from a rapid-fire gun, watching keenly from narrowed and scornful eyes the effect upon her.

Her very lips grew white. "Impossible!" she gasped. "Impossible!" Her surprise was as genuine as the slow, sickly pallor which had over-spread her face. He could not doubt her. Supremely clever woman as she was, she was incapable of this kind of acting. He gave a quick sob, almost a sob of relief. If not against him she would be for him and her assistance would be invaluable, especially since their interests were pooled.

"Then you," he stammered involuntarily, "you know nothing about it?"

"I!" Her eyes glittered in quick anger. "Of what are you thinking? Oh, I see." She was laughing now. "Oh, no, no, no! Dear me, no! That would not suit my game at all. If you knew the circumstances and, if I may venture to suggest it, myself better you would never have dreamed of such a thing. But," frowning now, "when and how were they taken? Begin at the beginning and tell me all about it."

"There is nothing much to tell," he said. "I sent for the photographs while still at the dinner-table intending to tell my guests the story of the mine, but—but—" He stammered a little. "I changed my mind. When we left the table I carried them with me, and placed them on the small table between the drawing-room windows."

"And left them there?" she asked quickly.

"Yes, after laying them on the table I dismissed them from my mind, had no further remembrance of them until this morning. Then I went to get them and found them gone. My first idea was that having the appointment with you for this afternoon so on my mind I had probably gotten up in the night and hidden the package somewhere, either when asleep or in a state of half-wakefulness; but Tatsu and I made a most thorough search of the entire apartment, over-looking no possible receptacle where I might have hidden them, and there is absolutely no trace of them."

"The servants," she said rapidly.

"I was coming to them. They were all taken on for the dinner, with the exception of Tatsu, who has been with me for years, and whom, I think, I would trust further than I would myself. When I questioned him he was extremely clear and quick in his answers. His story is that the extra servants all departed before my guests did, and that he personally saw them each one leave and locked the door after them. Then, after the guests had gone he locked up the other rooms very carefully and went to bed. This morning he got up early and put the whole apartment in order; and he is positive, and when Tatsu is positive he is not apt to be mistaken, that neither the photographs nor the maps were on that table, nor indeed anywhere in the rooms at five o'clock in the morning."

The Mariposa listened attentively to what he had to say, and then thought deeply for a few moments.

"There are only two possible explanations of the whole affair, which are in the least plausible," she said at last. "One is that some interested person or persons have heard of your find. It might be some prospector who has been tracking you for weeks, and he, or they may have stolen the papers with a view of communicating with the owners, whom they may know and whom they may fancy that you have not discovered. Your valet may or may not be a tool, that remains to be discovered. Well," resolutely, "in that case there is nothing to fear, I can assure you of that.

"The other hypothesis is that one of the guests had a motive for removing those especial maps and photographs, thus securing possession of them. But who and why?" As she pondered this question an expression of most startled and amused surprise swept over her face, and then she burst out laughing. "How funny!" she cried. "How awfully funny!" The peals of her silver laughter rang through the room.

"What is so awfully funny?" inquired Hayden politely, but with an irritation he could not conceal. "I assure you, it does not seem funny to me."

Ydo had evidently recovered her spirits; the sparkle had come back to her eyes, the color to her cheeks. "Don't bother any more," she counseled blithely. "It's all going to turn out right now. You see."

"I should prefer to know how." Hayden's irritation was increasing instead of diminishing, and he spoke more stiffly than before. "As it is a matter which concerns me primarily and which has caused me much worry I think it only fair that you should share with me the knowledge which seems to justify you in drawing such happy conclusions."

Hayden would never again be nearer losing his temper completely than he was at this moment, for Ydo, after gazing at him for a moment with a sort of whimsical, mock seriousness, again broke into laughter. "Who would ever have dreamed of her doing such a thing?" she apostrophized the ceiling.

"Her!" Hayden felt as if his heart had stopped beating for a moment and then begun again with slow and suffocating throbs. Perhaps Ydo saw or guessed something of his emotion, for she again repeated reassuringly: "It will be all right now within a few hours. You Will see."

"It's going to be dropped," he said in a dull, toneless voice. "It's my affair, Mademoiselle Mariposa, and you are not going to make the least move in the matter. Your suspicions—whichever one of my guests they affect, and I can not even surmise which one you are trying to implicate—are quite beside the mark. This is entirely my own affair, and I tell you, we are going to drop it. Do you hear?"

Ydo leaned forward, her chin upon her hand, and surveyed him with a humorous, unabashed and admiring scrutiny. "Brother in kind if not in kin, little brother of the wild, you are great. But do you mean what you say? Are you really willing to run the chance of giving up a fortune to protect—"

"Nonsense!" he broke in roughly. "Don't go any further. There's no use in talking the thing over." He again sank into somber silence.

But Ydo was apparently unmoved. "There is one thing I meant to ask you this afternoon," she said, "but since I shall probably not have an opportunity to do so I want my curiosity appeased. Why is that mine called The Veiled Mariposa? Did you happen to find out?"

"Yes," he answered, still entirely without interest. "Because, as the maps and photographs show, the only way to reach it is by a little hidden trail just back of a waterfall. You would never suspect it. I happened on it by the merest chance, followed it, and discovered that the mine lay behind this mountain cascade."

"Ah, beautiful!" Ydo clapped her hands. "I remember, I am sure, the very cascade. Although perhaps not, there were many."

"You have been on the ground then?" he asked.

"Ah, yes, with prospectors. But," with a shrug of the shoulders, "we were not so lucky as you."

"The interview for the afternoon is of course off," he said, rising heavily and stretching out his hand for his hat.

"I suppose so," conceded Ydo. She smiled and sighed. "The pretty little coup I had planned is smashed. I have been arranging it for weeks, ever since I learned that you were interested in—But the gods have decreed it differently and have taken the matter into their own hands. Ah, well! But I shall hear again from you to-day; and you will hear from me."