Early the following morning Kennedy left me alone in the laboratory and made a trip downtown, where he visited a South American tobacco dealer and placed a rush order for a couple of hundred cigarettes exactly similar in shape and quality to those which Mendoza had smoked and which the others seemed also to prefer, except, however, that the deadly drug was left out.

While he was gone, it occurred to me to take up again the hunt for Alfonso. Norton was not in his little office, nor could I find Alfonso anywhere about the campus. In fact he seemed to have almost dropped out of his University work for the time. Accordingly, I turned my steps toward the Prince Edward Albert Hotel, in the hope that he might be there.

Inquiries of the clerk at the desk told me that he had been there, but
was out just at that moment. I did not see Whitney around, nor the
Senora, so I sat down to wait, having nothing better to do until
Kennedy's return.

I was about to give it up and go, when I heard a cab drive up to the door and, looking up, I saw Alfonso get out. He saw me about the same time and we bowed. I do not think he even tried to avoid me.

"I haven't seen you for some time," I remarked, searching his face, which seemed to me to be paler than it had been.

"No," he replied. "I haven't been feeling very well lately and I've been running up into the country now and then to a quiet hotel—a sort of rest cure, I suppose you would call it. How are you? How is Senorita Inez?"

"Very well," I replied, wondering whether he had said what he did in the hope of establishing a complete alibi for the events of the night before.

Briefly I told him what had happened, omitting reference to the vocaphone and our real part in it.

"That is terrible," he exclaimed. "Oh, if she would only allow me to take care of her—I would take her back to our own country, where she would be safe, far away from these people who seek to prey on all of us."

He paced up and down nervously, and I could see that my information had added nothing to his peace of mind, though, at the same time, he had betrayed nothing on his part.

"I was just passing through," I said finally, looking at my watch, "and happened to see you. I hope your mother is well?"

"As well as is to be expected, surrounded by people who watch every act," he replied, I thought with a rap at us for having Norton about and so active, though I could not be sure.

We separated, and I hastened back to the laboratory to report to Craig that Alfonso was rusticating for his health.

Kennedy, on his part, had had an experience, though it was no more conclusive than my own. After he had left the tobacco district, he had walked up Wall Street to the subway. In the crowd he had seen Senora de Moche, although she had not seen him. He had turned and followed her until she entered the building in which Whitney and his associates had their offices. Whether it indicated that she was still leading them a chase, or they her, was impossible to determine, but it at least showed that they were still on friendly terms with each other.

In the laboratory he could always find something to do on the case, either in perfecting his chemical tests of the various drugs we had discovered, or in trying to decipher some similarities in the rough printing of the four warnings and the anonymous letter with the known handwriting of those connected with the case, many specimens of which he bad been quietly collecting. That in itself was a tremendously minute job, entailing not only a vast amount of expert knowledge such as he had collected in his years of studying crime scientifically, but the most exact measurements and careful weighing and balancing of trifles, which to the unscientific conveyed no meanings at all. Still, he seemed to be forging ahead, though he never betrayed what direction the evidence seemed to be taking.

The package of cigarettes which he had ordered downtown was delivered about an hour after his return and seemed to be the signal for him to drop work, for the meeting with Lockwood and Whitney had been set early. He stowed the package in his pockets and then went over to a cabinet in which he kept a number of rather uncommon drugs. From it he took a little vial which he shoved into his waistcoat pocket.

"Are you ready, Walter?" he asked.

"Whenever you are," I said, laying aside my writing.

Together we made our way down to the Mendoza apartment which had been the scene of the near-tragedy the night before. Outside, he paused for several moments to make inquiries about any suspicious persons that might have been seen lurking about the neighbourhood. None of the attendants in the apartment remembered having seen any, and they were now very alert after the two events, the murder and the attempted abduction. Not a clue seemed to have been left by the villain who had been called "Doc."

"How do you feel after your thrilling experience?" greeted Craig pleasantly, as Juanita admitted us and Inez came forward.

"Oh, Mr. Kennedy," she answered, with a note of sadness in her tone. "It makes me feel so alone in the world. If it were not for 'Nita—and you, I don't know what I should do."

"Doesn't Mr. Lockwood count?" asked Kennedy observantly.

"Of course—everything," she answered hastily. "But he has to be away so much on business, and—"

She paused and sighed. I could not help wondering whether, after all, his explanation of the dagger episode had been enough to satisfy her. Had she really accepted it?

Neither Lockwood nor Whitney had arrived, and Kennedy improved the opportunity to have a quiet talk aside with her, at which, I imagine, he was arranging a programme of what was to happen at this meeting and her part in it to co-operate with him.

She had left the room for a moment and we were alone. It was evidently a part of his plan, for no sooner was she gone than he opened the package of cigarettes which he had ordered and took out from the box in which Mendoza had kept his cigarettes those that were there, substituting those he had brought.

We had not long to wait, now. Lockwood and Whitney came together. I was interested to see the greeting of Inez and her lover. Was it pure fancy, or did I detect a trace of coldness as though there had sprung up something between them? As far as Lockwood was concerned, I felt sure that he was eager to break down any barrier that kept them from being as they had been.

Whitney took her hand and held it, in a playful sort of way. "I wish I were a young buck," he smiled. "No one would dare look at you—much less try to carry you off. Yes, we must be more careful of our little beauty, or we shall lose her."

They turned to greet us. I felt, as we shook hands, that it was much the same sort of handshake that one sees in the prize ring—to be followed by the clang of a bell, then all going to it, in battle royal, with the devil after the hindmost.

There was scarcely a chance for a preliminary bout before luncheon was announced, and we entered the cozy little dining-room to seat ourselves at the daintiest of tables. One could feel the hostess radiating hospitality, even on such a cross-current set of guests as we were, and for the time, I almost felt that it had been Kennedy's purpose to promote a love-feast instead of an armed truce.

Nothing was said about the main cause of our being together for some time, and the small talk almost lifted for a time the incubus that had settled down on all our lives since the tragedy in the den at the other end of the suite. But the fact could not be blinked.

Tacitly every one seemed to wait on Kennedy to sound the gong. Finally he did so.

"Of course," he began, clearing his throat, "there is no use making believe about anything. I think we all understand each other better now than we have ever done before. As for me, I am in this case under a promise to stick to it and fight it to the end. I suppose the rest of you are, also. But that need not prevent us agreeing on one thing. We can work together to protect Senorita Mendoza, at least, from such danger as threatened her last night."

"It's a dastardly shame," Lockwood exclaimed angrily, "that a man who would attempt a thing like that should go unpunished."

"Show me how to trace him and I'll guarantee the punishment," rejoined
Craig drily.

"I am not a detective," replied Lockwood.

Kennedy forebore to reply in kind, though I knew there was a ready answer on his tongue for the lover.

Ever since they had arrived, the Senorita had seen that they were well supplied with cigarettes from the case in which she and they supposed were the genuine South American brand of her father. Kennedy and I smoked them, too, although neither of us liked them very much. The others were smoking furiously.

"However," resumed Kennedy, "I do not feel that I want to intrude myself in this matter without being perfectly frank and having the approval of Senorita Mendoza. She has known both of you longer and more intimately than she has known me, although she has seen fit to place certain of her affairs in my hands, for which I trust I shall render a good account of my stewardship. It seems to me, though, that if there is, as we now know there is, some one whom we do not know"—he paused—"who has sunk so low as to wish to carry her off, apparently where she shall be out of the influence of her friends, it is only right that precautions should be taken to prevent it."

"What is your suggestion?" demanded Whitney, rather contentiously.

"Would there be any objection," asked Kennedy, "if I should ask my old friend,—or any of you may do it,—Deputy Commissioner O'Connor to detail a plainclothesman to watch this house and neighbourhood, especially at night?"

We watched the faces of the others. But it was really of no use.

"I think that is an excellent plan," decided Inez herself. "I shall feel much safer and surely none of you can be jealous of the city detectives."

Kennedy smiled. She had cut the Gordian knot with a blow. Neither Lockwood nor Whitney could object. The purpose of the luncheon was accomplished.

In fact he did not wait for further consideration, but excused himself from the table for a moment to call up our old friend O'Connor and tell him how gravely his man was needed. It was a matter of only a few minutes when he returned from the other room.

"He will detail Burke for this special service as long as we want him," reported Craig, sitting down again.

Inez was delighted, naturally, for the affair had been a terrific shock to her. I could see how relieved she felt, for I was sitting directly next to her.

The maid had, meanwhile brought in the coffee and Inez had been waiting to pour until Kennedy returned. She did not do so, now, either, however. It seemed as if she were waiting for some kind of signal from Kennedy.

"What a splendid view of the park you get here," remarked Kennedy turning toward the long, low windows that opened on a balustraded balcony. "Just look at that stream of automobiles passing on the west drive."

Common politeness dictated that all should turn and look, although there was no novelty in the sight for any of us.

As I have said, I was sitting next to Inez. To me she was a far more attractive sight than any view of the park. I barely looked out of the window. Imagine my surprise, then, at seeing her take advantage of the diversion to draw from the folds of her dress a little vial and pour a bit of yellowish, syrupy liquid into the cup of coffee which she was preparing for Whitney.

I could not help looking at her quickly. She saw that I had seen her and raised her other hand with a finger to her lips and an explanatory glance at Kennedy who was keeping the others interested. Instantly, I recognized the little vial which Craig had shoved into his waistcoat pocket. That had been the purpose of his whispered conference with her when we arrived. I said nothing, but determined to observe more closely.

More coffee and more cigarettes followed, always from the same box which was now on the table. The luncheon developed almost a real conversation. For the time, under the spell of our hostess, we nearly forgot that we were in reality bitter enemies.

My real interest, as time passed, centred in Whitney and I could not help watching him closely. Was it a fact, or was it merely my imagination? He seemed quite different. The pupils of his eyes did not seem to be quite so dilated as they had been at other times, or even when he arrived. Even his heart action appeared to be more normal. I think Inez noticed it, too. There was none of the wildness in his conversation, such as there often had been at other times.

Our party was prolonged beyond the time we had expected, but, although he had much on his mind, Kennedy made no move to break it up. In fact he did everything to encourage it.

At last, however, the others did notice the time, and I think it was with sincere regret that the truce was broken. Even then, no parting shots were indulged in.

As we left, Inez thanked Kennedy for his consideration, and I am sure that that in itself was reward enough. We parted from Lockwood, who wished to remain a little while, and rode down in the elevator with Whitney, a changed man.

"I'll walk over to the elevated with you," he said. "I was going to my hotel, but I think I'll go down to the office instead."

Evidently he had got Senora de Moche out of his mind, at least temporarily, I thought. Then for the first time I recalled that during the whole luncheon there had been no reference to either the Senora or Alfonso, though both must have been in our minds often.

"What was it you had Inez drop into Whitney's coffee?" I asked Craig as we parted from him and rode uptown.

"You saw that?" he smiled. "It was pilocarpine, jaborandi, a plant found largely in Brazil, one of the antidotes for stramonium poisoning. It doesn't work with every one. But it seems to have done so with him. Besides, the caffeine in the coffee probably aided the pilocarpine. Then, too, I made them smoke cigarettes without the dope that is being fed them. Lockwood's case, for some reason, hasn't gone far. But did you notice how the treatment contracted the pupils of Whitney's eyes almost back to normal again?"

I had and said so, adding, "But what was your idea?"

"I think I've got at the case from a brand-new angle," he replied. "Unless I am greatly mistaken, when the person who is doing the doping sees that Whitney is getting better—why, I think you all noticed it, Inez and Lockwood as well as you—it will mean another attempt to substitute more cigarettes doped with that drug. I think it's by substitution that it's being done. We'll see."

At the laboratory, Kennedy called Norton and described briefly what had happened, especially to Whitney.

"Now is your chance, Norton," he added, "to do some real good work. I want some one to watch the Senora, see if she, too, notes the difference in him. Understand?"

"Perfectly," returned Norton. "That is something I think I can do."