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?"