something very much like that anonymous letter I received. We both feel
that there is some one who wants to make trouble between us, and we are
not going to let it happen."
If she had known of Kennedy's discovery of the shoe-prints, I feel sure
that, as far as we were concerned, the case would have ended there. She
was in no mood to be convinced by such a thing, would probably have
insisted that some one was wearing a second-hand pair of his shoes.
Kennedy's eye had been travelling around the room as though searching
for something.
"May I have a cigarette out of that case over there?" he asked,
indicating a box of them on a table.
"Why--that is Mr. Lockwood's," she replied. "He left it here the last
time he was here and I forgot to send it to him. Wait a minute. Let me
get you some of father's."
She left the room. The moment the door closed Kennedy reached over and
took one from the case. "I have some of Lockwood's already, but another
won't matter, as long as I can get it," he said. "I thought it was her
father's. When she brings them, smoke one with me, and be careful to
save the stub. I want it."
A moment later she entered with a metal box that must have held several
hundred. Kennedy and I each took one and lighted it, then for several
minutes chatted as an excuse for staying. As for myself, I was glad
enough to leave a pretty large stub, for I did not like it. These
cigarettes, like those Whitney had offered us, had a peculiar flavour
which I had not acquired a liking for.
"You must let me know whether anything else develops from the meeting
in the tea room," said Kennedy finally, rising. "I shall be at the
laboratory some time, I think."
XIV
THE INTERFEROMETER
Norton was waiting for us at the laboratory when we returned, evidently
having been there some time.
"I was on my way to my apartment," he began, "when I thought I'd drop
in to see how things are progressing."
"Slowly," returned Kennedy, throwing off his street clothes and getting
into his laboratory togs.
"Have you seen Whitney since I had the break with him?" asked Norton, a
trifle anxiously.
I wondered whether Kennedy would tell Norton what to expect from
Whitney. He did not, however.
"Yes," he replied, "just now we had an appointment with Senora de Moche
and some others and ran into him at the hotel for a few moments."
"What did he say about me?" queried Norton.
"He hadn't changed his mind," evaded Kennedy. "Have you heard anything
from him?"
"Not a syllable. The break is final. Only I was wondering what he was
telling people about me. He'll tell them something--his side of the
case."
"Well," considered Kennedy, as though racking his brain for some remark
which he remembered, while Norton watched him eagerly, "I do recall
that he was terribly sore about the loss of the dagger, and seemed to
think that it was your fault."
"I thought so, I knew it," replied Norton bitterly. "I can see it
coming. All the trustees will hear of my gross negligence in letting
the Museum be robbed. I suppose I ought to sit up there all night. Oh,
by the way, there's another thing I wanted to ask you. Have you ever
done anything with those shoe-prints you found in the dust of the mummy
case?"
I glanced at Kennedy, wondering whether he felt that the time had come
to reveal what he had discovered. He said nothing for a moment, but
reached into a drawer and pulled out the papers, which I recognized.
"Here they are," he said, picking out the original impression which he
had taken.
"Yes," repeated Norton, "but have you been able to do anything toward
identifying them?"
"I found it rather hard to collect prints of the shoes of all of those
I wished to compare. But I have them at last."
"And?" demanded Norton, leaning forward tensely.
"I find that there is one person whose shoe-prints are precisely the
same as those we found in the Museum," went on Kennedy, tossing over
the impression he had taken.
Norton scanned the two carefully. "I'm not a criminologist," he said
excitedly, "but to my untrained eye it does seem as though you had here
a replica of the first prints, all right." He laid them down and looked
squarely at Kennedy. "Do you mind telling me whose feet made these
prints?"
"Turn the second over. You will see the name written on it."
"Lockwood!" exclaimed Norton in a gasp as he read the name. "No--you
don't mean it."
"I mean nothing less," repeated Kennedy firmly. "I do not say what
happened afterwards, but Lockwood was in the Museum, hiding in the
mummy case, that night."
Norton's mind was evidently working rapidly. "I wish I had your power
of deduction, Kennedy," he said, at length. "I suppose you realize what
this means?"
"What does it mean to you?" asked Kennedy, changing front.
Norton hesitated. "Well," he replied, "it means to me, I suppose, what
it means to any one who stops to think. If Lockwood was there, he got
the dagger. If he had the dagger--it was he who used it!"
The inference was so strong that Craig could not deny it. Whether it
was his opinion or not was another matter.
"It fits in with other facts, too," continued Norton. "For instance, it
was Lockwood who discovered the body of Mendoza."
"But the elevator boy took Lockwood up himself," objected Craig, more
for the sake of promoting the discussion than to combat Norton.
"Yes--when he 'discovered' the thing. But it must have been done long
before. Who knows? He may have entered. The deed might have been done.
He may have left. No one saw him come or go. What then more likely to
cover himself up than to return when he knew that his entrance would be
known, and find the thing himself?"
Norton's reasoning was clever and plausible. Yet Kennedy scarcely
nodded his head, one way or the other.
"You were acquainted with Lockwood?" he asked finally. "I mean to say,
of course, before this affair."
"Yes, I met him in Lima just as I was starting out on my expedition. He
was preparing to come to New York."
"What did you think of him then?"
"Oh, he was all right, I suppose. He wasn't the sort who would care
much for an archaeologist. He cared more for a prospector going off
into the hills than he did for me. And I--I admit that I am impossible.
Archaeology is my life."
Norton continued to study the prints. "I can hardly believe my eyes,"
he murmured; then he looked up suddenly. "Does Whitney know about
this--or Lockwood?"
Kennedy shook his head negatively.
"Because," pursued Norton, "an added inference to that I spoke of would
be that the reason why they are so sure that they will find the
treasure is that they are not going on tradition, as they say, but on
the fact itself."
"A fair conclusion," agreed Craig.
"I wish the break could have been postponed," continued Norton. "Then I
might have been of some service in my relation to Whitney. It's too
late for me to be able to help you in that direction now, however."
"There is something you can do, though," said Craig.
"I shall be delighted," hastened Norton. "What is it?"
"You know Senora de Moche and Alfonso?"
"Yes."
"I wish that you would cultivate their acquaintance. I feel that they
are very suspicious of me. Perhaps they may not be so with you."
"Is there any special thing you want to find out?"
"Yes--only I have slight hopes of doing so. You know that she is on
most intimate terms with Whitney."
"I'm afraid I can't do much for you, then. She'll fight shy of me.
He'll tell her his story."
"That will make no difference. She has already warned me against him.
He has warned against her. It's a most remarkable situation. He is
trying to get her into some kind of deal, yet all the time he is afraid
she is double-crossing him. And at the same time he obeys her--well,
like Alfonso would Inez if she'd only let him."
Norton frowned. "I don't like the way they hover about Inez Mendoza,"
he remarked. "Perhaps the Senora is after Whitney, while her son is
after Inez. Lockwood seems to be impervious to her. Yes, I'll undertake
that commission for you, only I can't promise what success I'll have."
Kennedy restored the shoe-prints to the drawer.
"I think that's gratifying progress," went on Norton. "First we know
who stole the dagger. We know that the dagger killed Mendoza. You have
even determined what the poison on the blade was. It seems to me that
it remains only to determine who struck the actual blow. I tell you,
Kennedy, Whitney will regret the day that he ever threw me over on so
trivial a pretext."
Norton was pacing up and down excitedly now.
"My only fear is," he went on, "what the shock of such a thing will be
on that poor little girl. First her father, then Lockwood. Why--the
blow will be terrible. You must be careful, Kennedy."
"Never fear about that," reassured Craig. "Not a word of this has been
breathed to her yet. We are a long way from fixing the guilt of the
murder; inference is one thing, fact another. We must have facts. And
the facts I want, which you may be able to get, relate to the strange
actions of the de Moches."
Norton scanned Kennedy's face for some hint of what was back of the
remark. But there was nothing there.
"They will bear watching, all right," he said, as he rose to go. "Old
Mendoza was never quite the same after he became so intimate with her.
And I think I can see a change in Whitney."
"What do you attribute it to?" asked Kennedy, without admitting that it
had attracted his attention, too.
"I haven't the slightest idea," confessed Norton.
"Inez is as afraid of her as any of the rest," remarked Kennedy
thoughtfully. "She says it is the evil eye."
"Not an uncommon belief among Latin-Americans," commented Norton. "In
fact, I suppose there are people among us who believe in the evil eye
yet. Still, you can hardly blame that little girl for believing it is
almost anything. Well, I won't keep you any longer. I shall let you
know of anything I find out from the de Moches. I think you are getting
on remarkably."
Norton left us, his face much brighter than it had been when we met him
at the door.
Kennedy, alone at last in the laboratory, went over to a cabinet and
took out a peculiar-looking apparatus, which seemed, as nearly as I can
describe it, to consist of a sort of triangular prism, set with its
edge vertically on a rigid platform attached to a massive stand of
brass.
"Norton seems to have suddenly become quite solicitous of the welfare
of Senorita Mendoza," I hazarded, as he worked over the adjustment of
the thing.
Kennedy smiled. "Every one seems to be--even Whitney," he returned,
twisting a set-screw until he had the alignment of the various parts as
he wanted it.
The telephone bell rang.
"Do you want to answer it?" I asked Craig.
"No," he replied, not even looking up from his work. "Find out who it
is. Unless it is something very important say I am out on an
investigation and that you have heard from me; that I shall not be
either at the laboratory or the apartment until tomorrow morning. I
must get this done to-night."
I took down the receiver.
"Hello, is this Professor Kennedy?" I recognized a voice.
"No," I replied. "Is there any message I can take?"
"This is Mr. Lockwood," came back the information I had already
guessed. "When do you expect him?"
"It's Lockwood," I whispered to Craig, my hand over the transmitter.
"See what he wants," returned Craig. "Tell him what I told you."
I repeated Kennedy's message.
"Well, that's too bad," replied Lockwood. "I've just seen Mr. Whitney,
and he tells me that Kennedy and you are pretty friendly with Norton,
Of course, I knew that. I saw you at the Mendozas' together the first
time. I'd like to have a talk with him about that man. I suppose he has
told you all his side of the story of his relations with Whitney."
I am, if anything, a good listener, and so I said nothing, not even
that he had better tell it to Kennedy in the morning, for it was such a
novelty to have any of these people talk voluntarily that I really
didn't much care whether I believed what they said or not.
"I used to know him down in Lima, you know," went on Lockwood. "What I
want to say has to do with that dagger he says was stolen. I want to
tell what I know of how he got it. There was an Indian mixed up in it
who committed suicide--well, you tell Kennedy I'll see him in the
morning."
Lockwood rang off, and I repeated what he had told me, as Kennedy
continued to adjust the apparatus.
"Say," I exclaimed, as I finished. "That was a harry's of a commission
you gave Norton just now, watching the de Moches. Why, they'd eat him
alive if they got a chance, and I don't know that all's like a Sunday
school on his part. Lockwood doesn't seem to think so."
Kennedy smiled quietly. "That was why I asked him to do it," he
returned. "I thought that he wouldn't let much escape him. They all
seem so down on him, he'll have to watch out. It will keep him busy,
too, and that means a chance for us to work."
He had finished setting up the machine, and now went over to another
drawer, from which he took the envelope of stubs which we had taken
down at Whitney's office first. Then from the pocket of his street coat
he drew both the second envelope of ashes and stubs, the whole
cigarette from Lockwood's case, and the stubs which both of us had
saved from the cigarettes that had once belonged to Mendoza.
Carefully he separated and labelled them all, so that there would be no
chance for them to get mixed up. Then he picked up one of the stubs and
lighted it. The smoke curled up in wreaths between a powerful light and
the peculiar instrument, while Craig peered through a lens,
manipulating the thing with exhaustless patience and skill. I watched
him curiously, but said nothing, for he was studying something
carefully, and I did not want to interrupt his train of thought.
Finally he beckoned me over. "Can you make anything out of that?" he
asked.
I looked through the eye-piece, also. On a sort of fine grating all I
could see was a number of strange lines.
"If you want an opinion from me," I said, with a laugh, "you'll have to
tell me first what I am looking at."
"That," he explained, as I continued to gaze, "is one of the latest
forms of the spectroscope, known as the interferometer, with delicately
ruled gratings in which power to resolve the straight, close lines in
the spectrum is carried to the limit of possibility. A small watch is
delicate. But it bears no comparison to the delicacy of these
defraction spectroscopes.
"Every substance, you know, is, when radiating light, characterized by
what at first appears to be almost haphazard sets of spectral bands
without relation to one another. But they are related by mathematical
laws, and the apparent haphazard character is only the result of our
lack of knowledge of how to interpret the results."
He resumed his place at the eye-piece to check over his results.
"Walter," he said finally, looking up at me with a twinkle in his eye,
"I wish that you'd go out and find me a cat."
"A cat?" I repeated.
"Yes, a cat--felis domesticus, if it sounds better that way--a plain,
ordinary cat."
I jammed on my hat and, late as it was, sallied forth on this
apparently ridiculous mission.
Several belated passers-by and a policeman watched me as though I were
a house-breaker, and I felt like a fool, but at last, by perseverance
and tact, I managed to capture a fairly good specimen of the species,
and carried it in my arms to the laboratory with some profanity and
many scratches.
XV
THE WEED OF MADNESS
In my absence Craig had set to work on a peculiar apparatus, as though
he were distilling something from several of the cigarette stubs which
he had been studying by means of the interferometer.
"Here's your confounded cat," I ejaculated, as I placed the unhappy
feline in a basket and waited patiently until finally he seemed to be
rewarded for his patient labours. It was well along toward morning when
he obtained in a test-tube a few drops of a colourless, odourless
liquid.
"My interferometer gave me a clue," he remarked, as he held the tube up
with satisfaction. "Without the tell-tale line in the spectrum which I
was able to discover by its use I might have been hunting yet for it.
It is so rare that no one would ever have thought, offhand, I suppose,
to look for it. But here it is, I'm sure, only I wanted to be able to
test it."
"So you are not going to try it on yourself," I said sarcastically,
referring to his last experiment with a poison. "This time you are
going to make the cat the dog."
"The cat will be better to test it on than a human being," he replied,
with a glance that made me wince, for, after his performance with the
curare, I felt that once the scientific furore was on him I might be
called upon to become an unwilling martyr to science.
It was with an air of relief, both for himself and my own peace and
safety, that I saw him take the cat out of the basket and hold her in
his arms, smoothing her fur gently, to quiet the feelings that I had
severely ruffled.
Then with a dropper he sucked up a bit of the liquid from the
test-tube. I watched him intently as he let a small drop fall into the
eye of the cat.
The cat blinked a moment, and I bent over to observe it more closely.
"It won't hurt the cat," he explained, "and it may help us."
As I looked at the cat's eye it seemed to enlarge, even under the glare
of a light, shining forth, as it were, like the proverbial cat's eye
under a bed.
What did it mean?
Was there such a thing, I wondered hastily, as the drug of the evil eye?
"What have you found?" I queried.
"Something very much like the so-called 'weed of madness,' I think," he
replied slowly.
"The weed of madness?" I repeated.
"Yes. It is similar to the Mexican toloache and the Hindu datura, which
you must have heard about."
I had heard of these weird drugs, but they had always seemed to be so
far away and to belong rather to the atmosphere of civilizations
different from New York. Yet, I reflected, what was to prevent the
appearance of anything in such a cosmopolitan city, especially in a
case so unusual as that which had so far baffled even Kennedy's skill?
"You know the jimson weed--the Jamestown weed, as it is so often
called?" he continued, explaining. "It grows almost everywhere in the
world, but most thrivingly in the tropics. All the poisons that I have
mentioned are related to it in some way, I believe."
"I've seen the thing in lots and fields," I replied, "but I never
thought it was of much importance."
"Well," he resumed, "the jimson weed on the Pacific coast, in some
parts of the Andes, has large white flowers which exhale a faint,
repulsive odour. It is a harmless-looking plant, with its thick tangle
of leaves, a coarse green growth, with trumpet-shaped flowers. But to
one who knows its properties it is quite too dangerously convenient for
safety."
"But what has that to do with the evil eye?" I asked.
"Nothing; but it has much to do with the cigarettes that Whitney is
smoking," he went on positively. "Those cigarettes have been doped!"
"Doped?" I interrogated, in surprise. "With this weed of madness, as
you call it?"
"No, it isn't toloache that was used," he corrected. "I think it must
be some particularly virulent variety of the jimson weed that was used,
though that same weed in Mexico is, I am sure, what there they call
toloache. Perhaps its virulence in this case lies in the method of
concentration in preparing it. For instance, the seeds of the
stramonium, which is the same thing, contain a much higher percentage
of poison than the leaves and flowers. Perhaps the seeds were used. I
can't say. But, then, that isn't at all necessary. It is the fact of
its use that concerns us most now."
He took a drop of the liquid which he had isolated and added a drop of
nitric acid. Then he evaporated it by gentle heat and it left a residue
slightly yellow.
Next he took from the shelf over his table a bottle marked "Alcoholic
Solution--Potassium Hydrate." He opened it and let a drop fall on the
place where the liquid had evaporated.
Instantly the residue became a beautiful purple, turning rapidly to
violet, then to dark red, and, finally, it disappeared altogether.
"Stramonium, all right," he nodded, with satisfaction at the
achievement of his night's labours. "That was known as Vitali's test.
Yes, there was stramonium in those cigarettes--datura
stramonium--perhaps a trace of hyoscyamine."
I tried to look wise, but all I could think of was that, whatever his
science showed me now, my instinct had been enough to prompt me not to
smoke those cigarettes, though, of course, only Kennedy's science could
tell what it was that caused that instinctive aversion.
"They are all like atropine, mydriatic alkaloids," he proceeded, "so
called from the effect they have on the eye. Why, one-one hundred
thousandth of a grain will affect the eye of a cat. You saw how it
acted on our subject. It is more active in that way than atropine.
Better yet, you remember how Whitney's eyes looked, how Inez said her
father stared, and how she feared for Lockwood?"
"I remember," I said, still not able to detach the evil-eye idea quite
from my mind. "How about the Senora's eyes? What makes them so--well,
effective?"
"Oh," Craig answered quickly, "her pupils were normal enough. Didn't
you notice that? It was the difference in Whitney's and the others'
that first suggested making some tests."
"What is the effect?" I asked, wondering whether it might have
contributed to the cause of Mendoza's death.
"The concentrated poison which has been used in these cigarettes does
not kill--at least not outright. It is worse than that. Slowly it
accumulates in the system. It acts on the brain."
I was listening, spellbound, as he made his disclosure. No wonder, I
thought, even a scientific criminal stood in awe of Craig.
"Of all the dangers to be met with in superstitious countries, these
mydratic alkaloids are among the worst. They offer a chance for crimes
of the most fiendish nature--worse than with the gun or the stiletto.
They are worse because there is so little fear of detection. That crime
is the production of insanity!"
Horrible though the idea, and repulsive, I could not doubt it in the
face of Craig's investigations and what I had already seen with my own
eyes. In fact, it was necessary for me only to recall the mild
sensations I myself had experienced, in order to be convinced of the
possible effect intended by the insidious poison contained in the many
cigarettes which Whitney, for instance, had smoked.
"But don't you suppose they know it?" I wondered. "Can't they tell it?"
"I suppose they have gradually become accustomed to it," Craig
ventured. "If you have ever smoked one particular brand of cigarette
you must have noticed how the manufacturer can gradually substitute a
cheaper grade of tobacco without any large number of his patrons
knowing anything about it. I imagine it might have been done in some
way like that."
"But you would think they'd feel the effect and attribute it to
smoking."
"Perhaps they do feel the effect. But when it comes to tracing causes,
some people are loath to admit that tobacco and liquor can be the root
of the evil. No, some one is slipping these cigarettes in on them,
perhaps substituting the doped brand for those that are ordered. If you
will notice, both Whitney and Lockwood have cigarettes that are made
especially for them. So had Mendoza. It is a circumstance which some
one has turned to account, though how and by whom the substitution has
been made I cannot say yet. I wish I had time to follow out this one
line, to the exclusion of everything else. But I've got to keep my
fingers on every rope at once, else the thing will pull away from me.
It is enough for the present that we know what the poison is. I shall
take up the tracing of the person who is administering it the moment I
get a hint."
It was almost daylight before Craig and I left the laboratory after his
discovery of the manner of the cigarette poisoning by stramonium. But
that was the only way in which he was able to make progress--taking
time for each separate point by main force.
I was thoroughly tired, though not so much so that my dreams were not
haunted by a succession of baleful eyes peering at me from the darkness.