Norton had scarcely gone, and Kennedy was still studying the four pieces of paper on which the warning had been given, when our laboratory door was softly pushed open again.

It was Senorita Mendoza, looking more beautiful than ever in her plain black mourning dress, the unnatural pallor of her face heightening the wonderful lustrous eyes that looked about as though half frightened at what she was doing.

"I hope nothing has happened," greeted Kennedy, placing an easy-chair for her. "But I'm glad to see that you have confidence enough to trust me."

She looked about doubtfully at the vast amount of paraphernalia which Craig had collected in his scientific warfare on crime. Though she did not understand it, it seemed to impress her.

"No," she murmured, "nothing new has happened. You told me to call on you if I should think of anything else."

She said it with an air as if confessing something. It was apparent that, whatever it was, she had known it all the time and only after a struggle had brought herself to telling it.

"Then you have thought of something?" prompted Craig.

"Yes," she replied in a low tone. Then with an effort she went on: "I don't know whether you know it or not, but my family is an old one, one of the oldest in Peru."

Kennedy nodded encouragingly.

"Back in the old days, after Pizarro," she hurried on, no longer able to choose her words, but blurting the thing out directly, "an ancestor of mine was murdered by an Inca dagger."

She stopped again and looked about, actually frightened at her own temerity, evidently. Kennedy and his twentieth-century surroundings seemed again to reassure her.

"I can't tell you the story," she resumed. "I don't know it. My father knew it. But it was some kind of family secret, for he never told me. Once when I asked him he put me off; told me to wait until I was a little older."

"And you think that may have something to do with the case?" asked
Kennedy, trying to draw out anything more that she knew.

"I don't know," she answered frankly. "But don't you think that it is strange—an ancestor of mine murdered and now, hundreds of years afterward, my father, the last of his line in direct descent, murdered in the same way, by an Inca dagger that has disappeared?"

"Then you were listening while I was talking to Professor Norton?" shot out Kennedy, not unkindly, but rather as a surprise test to see what she would say.

"You cannot blame me for that," she returned simply.

"Hardly," smiled Kennedy. "And I appreciate your reticence—as well as your coming here finally to tell me. Indeed, it is strange. Surely you must have some other suspicions," he persisted, "something that you feel, even though you do not know?"

Kennedy was leaning forward, looking deeply into her eyes, as if he would read what was passing in her mind. She met his gaze for a moment, then looked away.

"You heard Mr. Lockwood say that he had become associated with a Mr.
Whitney, Mr. Stuart Whitney, down in Wall Street?" she ventured.

Kennedy did not take his eyes from her face as he sought to extract the reluctant words from her.

"Mr. Whitney has been largely interested in Peru, in business and in mining," she went on slowly. "He has given large sums to scholars down there, to Professor Norton's expeditions from New York. I—I'm afraid of that Mr. Whitney!"

Her quiet tone had risen to a pitch of tremulous excitement. Her face, which had been pale from the strain of the tragedy, was now full of colour, and her breast rose and fell with suppressed emotion.

"Afraid of him—why?" asked Kennedy.

There was no more reticence. Once having said so much, she seemed to feel that she must go on and tell her fears.

"Because," she went on, "he—he knows a woman—whom my father knew." A sudden flash of fire seemed to light up her dark eyes. "A woman of Truxillo," she continued, "Senora de Moche."

"De Moche," repeated Kennedy, recalling the name and a still unexplained incident of our first interview. "Who is this Senora de Moche?" he asked, studying her as if she had been under a lens.

"A Peruvian of an old Indian family," she replied, in a low tone, as if
the words were forced from her. "She has come to New York with her son,
Alfonso. You remember—you met him. He is studying here at the
University."

Again I noted the different manner in which she spoke the two names of mother and son. Evidently there was some feud, some barrier between her and the elder woman, which did not extend to Alfonso.

Kennedy reached for the University catalogue and found the name, "Alfonso de Moche." He was, as he had told us, a post-graduate student in the engineering school and, therefore, not in any of Kennedy's own classes.

"You say your father knew the Senora?" asked Kennedy.

"Yes," she replied, in a low voice, "he had had some dealings with her.
I cannot say just what they were; I do not know. Socially, of course,
it was different. They did not belong to the same circle as ours in
Lima."

From her tone I gathered that there existed a race prejudice between those of old Spanish descent and the descendants of the Indians. That, however, could not account for her attitude. At least with her the prejudice did not extend to Alfonso.

"Senora de Moche is a friend of Mr. Whitney?" queried Kennedy.

"Yes, I believe she has placed some of her affairs in his hands. The de Moches live at the Prince Edward Albert Hotel, and Mr. Whitney lives there, too. I suppose they see more or less of each other."

"H-m," mused Kennedy. "You know Mr. Whitney, I suppose?"

"Not very well," she answered. "Of course, I have met him. He has been
to visit my father, and my father has been down at his office, with Mr.
Lockwood. But I do not know much about him, except that he is what you
Americans call a promoter."

Apparently, Inez was endeavouring to be frank in telling her suspicions, much more so even than Norton had been. But I could not help feeling that she was trying to shield some one, though not to the extent of consciously putting us on a wrong scent.

"I shall try to see Mr. Whitney as soon as possible," said Kennedy, as she rose to go. "And Senora de Moche, too."

I fancied that Senorita Inez, although she had not told us much, felt relieved.

Again she murmured her thanks as she left and again Kennedy repeated his injunction to tell everything that happened that could possibly have any bearing on the case.

"That's a rather peculiar phase," he considered, when we were alone, "this de Moche affair."

"Yes," I agreed. "Do you suppose that woman could be using Whitney for some purpose?"

"Or Whitney using her," suggested Kennedy. "There's so much to be done at once that I hardly know where to begin. We must see both of them as soon as possible. Meanwhile, that message from Dr. Leslie about the poison interests me. I must at least start my tests of the blood samples that I extracted. Walter, may I ask you to leave me here in the laboratory undisturbed?"

I had some writing on my news story to do, and went into the room next to the laboratory, where I was soon busily engaged tapping my typewriter. Suddenly I became conscious of that feeling, which Kennedy had hinted at, of being watched. Perhaps I had heard a footstep outside and was not consciously aware of it. But, at any rate, I had the feeling.

I stopped tapping the keys and wheeled unexpectedly about in my chair. I am sure that I caught just a fleeting glimpse of a face dodging back from the window, which was on the first floor.

Whose face it was I am not prepared to assert exactly. But there was a face, and the fleeting glimpse of the eyes and forehead was just enough to give me the impression that they were familiar, without enabling me to identify them. At any rate, the occurrence made me feel decidedly uncomfortable, especially after the warning letters that we had all received.

I sprang to my feet and ran to the door. But it was too late. The intruder had disappeared. Still, the more I thought about it, the more determined I was to try to verify an indistinct suspicion, if possible. I put on my hat and walked hurriedly over to the office of the registrar.

Sure enough, I found that Alfonso de Moche had been at the University that day, must have attended a lecture an hour or so before. Having nothing else to do, I hunted up some of his professors and tried to quiz them about him.

As I had expected, they told me that he was an excellent student, though very quiet and reserved. His mind seemed to run along the line of engineering, and particularly mining. I could not help coming to the conclusion that undoubtedly he, too, was infected by the furore for treasure hunting, in spite of his Indian ancestry.

Yet there seemed to be surprisingly little known about him outside of the lecture room and laboratory. The professors knew that he lived with his mother at a hotel downtown. He seemed to have little or nothing to do with the other students outside of class work. Altogether he was an enigma, as far as the social life of the University went. It looked very much as though he had come to New York quietly to prepare himself for the search for the buried treasure. Had the Gold of the Gods lured him into its net, too?

Reflecting on the tangle of events, the strange actions of Lockwood and the ambitions of Whitney, I retraced my steps in the direction of the laboratory, convinced that de Moche had employed at least a part of his time lately in spying on us. Perhaps he had seen Inez going in and out. Suddenly it flashed over me that the interchange of glances between de Moche and Lockwood indicated that she was more to him than a mere acquaintance. Perhaps it had been jealousy as well as treasure hunting that had prompted his eavesdropping.

Still reflecting, I decided to turn in at the Museum and have a chat with Norton. I found him nervously pacing up and down the little office that had been accorded him in his section of the building.

"I can't rid my mind of that warning," he remarked anxiously, pausing in his measured tread. "It seems inconceivable to me that any one would take the trouble to send four such warnings unless he meant it."

"Quite so," I agreed, relating to him what had just happened.

"I thought of something like that," he acquiesced, "and I have already taken some precautions."

Norton waved his hand at the windows, which I had not noticed before. Though they were some distance above the ground, I saw now that he had closed and barred them at the expense of ventilation. The warnings seemed to have made more of an impression on him than on any of the rest of us.

"One never can tell where or when a blow will fall with these people," he explained. "You see, I've lived among them. They are a hot-blooded race. Besides, as you perhaps have read, they have some queer poisons down in South America. I mean to run no unnecessary chances."

"I suppose you suspected all along that the dagger had something to do with the Gold of the Gods, did you not?" I hinted.

Norton paused before answering, as though to weigh his words. "Suspected—yes," he replied. "But, as I told you, I have had no chance to read the inscription on it. I can't say that I took it very seriously—until now."

"It's not possible that Stuart Whitney, who, I understand, is deeply interested in South America, may have had some inkling of the value of the dagger, is it?" I asked thoughtfully.

For a full minute Norton gazed at me. "I hadn't thought of that," he admitted at length. "That's a new idea to me."

Yet somehow I knew that Norton had thought of it, though he had not yet spoken about it. Was it through loyalty to the man who had contributed to financing his expeditions to South America?

"Do you know Senora de Moche well?" I ventured, a moment later.

"Fairly well," he replied. "Why?"

"What do you think of her?"

"Rather a clever woman," he replied noncommittally.

"I suppose all the people in New York who were interested in Peru knew her," I pursued, adding, "Mr. Whitney, Mendoza, Lockwood."

Norton hesitated, as though he was afraid of saying too much. While I could not help admiring his caution, I found that it was most exasperating. Still, I was determined to get at his point of view, if possible.

"Alfonso seems to be a worthy son, then," I remarked. "I can't quite make out, though, why the Senorita should have such an obvious prejudice against her. It doesn't seem to extend to him."

"I believe," replied Norton reluctantly, "that Mendoza had been on rather intimate terms with her. At least, I think you'll find the woman very ambitious for her son. I don't think she would have stopped at much to advance his interests. You must have noticed how much Alfonso thinks of the Senorita. But I don't think there was anything that could have overcome the old Castilian's prejudice. You know they pride themselves on never intermarrying. With Lockwood it would have been different."

I thought I began to get some glimmering of how things were.

"Whitney knows her pretty well now, doesn't he?" I shot out.

Norton shrugged his shoulders. But he could not have acquiesced better than by his very manner.

"Mr. Lockwood and Mr. Whitney know best what they are doing," he
remarked, at length. "Why don't you and Kennedy try to see Senora de
Moche? I'm a scientist, you know. I dislike talking about speculations.
I'd prefer only to express opinions about things that are certainties."

Perhaps Norton wished to convey the impression that the subjects I had broached were worth looking into. At least it was the impression I derived.

"Still," he continued slowly, "I think I am justified in saying this much: I myself have been interested in watching both Alfonso de Moche and Lockwood when it comes to the case of the Senorita. All's fair, they say, in love and war. If I am any judge, there are both in this case, somewhere. I think you had better see the Senora and judge for yourself. She's a clever woman, I know. But I'm sure that Kennedy could make her out, even if the rest of us can't."

I thanked Norton for the hint that he had given, and after chatting a few moments more left him alone in his office.

In my room again, I went back to finish my writing. Nothing further occurred, however, to excite my suspicions, and at last I managed to finish it.

I was correcting what I had written when the door opened from the laboratory and Craig entered. He had thrown off his old, acid-stained laboratory smock and was now dressed to venture forth.

"Have you found out anything about the poison?" I asked.

"Nothing definite yet," he replied. "That will take some time now. It's a strange poison—an alkaloid, I'm sure, but not one that one ordinarily encounters. Still, I've made a good beginning. It won't take long to determine it now."

Craig listened with deep interest, though without comment, when I related what had happened, both Norton's conversation and about the strange visitor whom we had had peering into our windows.

"Some one seems to be very much interested in what we are doing, Walter," he concluded simply. "I think we'd better do a little more outside work now, while we have a chance. If you are ready, so am I. I want to see what sort of treasure hunter this Stuart Whitney is. I'd like to know whether he is in on this secret of the Gold of the Gods, too."