"At any rate, as we learned more about the subconscious effects of various elements of Dream Park, we began to wonder if a more

direct manipulation of the subconscious might be a fruitful area for study. Since we only want to use those techniques within the attractions themselves, we didn't have to worry about the existing statutes covering subliminal advertising."

Skip showed them his first real smile since entering the office. "Some of it was almost absurdly easy once we set our minds to it. We started with sounds. Some frequencies in the subsonic range are well known to stimulate uneasiness or fear. We started with the buzzing sound that angry bees make. When we were satisfied that we could produce fear response in more than eighty percent of our test subjects, we went on from there.

"High-speed light flashes were even more effective. In the early days, such techniques could only be used on people watching pro-. jection screens or billboards, flashing a message lasting for only hundredths of a second. Our holographic projection techniques take us far beyond that. We can broadcast separate images to two people standing side by side. Effectiveness with this technique isn't where we would like it-only about sixty percent right now-but the flexibility is enormous."

He looked up from his viewscreen, folding the lid of his brief­case down. He had been speaking distractedly, as if one part of his mind were collating information while the other part related it to them.

"Human beings have four basic kinds of sensory receptors. Electromagnetic, mechanoreceptors, thermoreceptors, and chemo­receptors. The rods and cones of the eye are electromagnetic receptors. Mechanoreceptors respond to touch, pressure, et cetera. For instance, the eardrums are mechanoreceptors; they respond to the pressure of sound waves. Thermoreceptors are free nerve end­ings sensitive to heat and cold. We've done work in each of these areas, with the promise of more to come. We had trouble with chemoreceptors. Taste buds, the cells of the carotid and aortic bodies, the olfactory cells of the nose... we couldn't do much with those, so naturally that was where we concentrated our efforts."

Griffin drummed his fingers on the arms of his chair and cleared his throat. "I take it that whatever was stolen was a result of these efforts?"

O'Brien looked sheepish. "Am I going on too much? I thought some background would be useful."

"Go ahead, Skip, there might be something valuable in even the trivia."

"0-kay. Our problems were manyfold: accuracy of the effect, harmlessness of the chemical agent, undetectability, means of dis­tribution, et cetera. We made an abortive effort to trigger the ol­factory nerves with sound, but it just won't work. The receptors respond only to chemicals.

"The potential is tremendous, gentlemen. The olfactory nerves are the only ones that connect directly to the brain. The medial ol­factory lobe seems to be involved with the limbic system in the ex­pression of emotion. There is believed to be a ‘pleasure center' lo­cated there.

"As I said, the olfactory cells need a chemical to trigger them. What they are, actually, are bipolar nerve cells originating from the central nervous system itself. When one is triggered it becomes ‘depolarized,' which causes a battery effect, and a current flows. Voila, a nervous impulse. Present theory holds that the molecular shape, rather than the chemical properties of a substance, deter­mines its smell. On the basis of this theory, seven different pri­mary classes of odor have been established: camphoraceous, musky, floral, pepperminty, ethereal, pungent, and putrid. Of course these can be combined. What we theorized is that there are ‘neutral' scents, scents which trigger depolarization in the olfac­tory nerves without any conscious sensation of smell. If we could find the molecular shape which accomplishes this, we would be on our way."

"How many different kinds of response were you hoping to get?" Harmony asked from behind his peaked fingers, eyes still deceptively lidded.

"We weren't sure. Nausea, salivation, sexual behavior, and-"

"Sexual behavior?"

"Everybody triggers on that one. Yes, sexual behavior. As f at back as the 1960's two chemicals, copulin and androsterone, were found to be sexual signals in monkeys, and to some extent in human beings. Humans have a more complex set of factors h~­volved in attraction than animals. Many of them are social in na­ture and no chemical yet discovered can really make up your mind for you." He grinned. "But we're trying."

O'Brien extracted a cigarette from his inside coat pocket and lit it with an unsteady hand. At a glance from Griffin Harmony unob­

trusively turned on a tiny fan in the ceiling, and Skip's smoke vanished into it.

"What we did," he began again, "was to use an advanced ver­sion of a device called an electro-olfactograph, which registers electrical impulses in the olfactory nerves. We finally found a sub­stance that causes depolarization without conscious recognition of scent at any concentration."

"What was the chemical?"

"I couldn't give you the formula, Alex. I don't know it myself. I can say that it was a highly volatile lipid-soluble chemical, with saline as the carrying agent. Once we had that, the work really began. It was really incredible. This was all about seven months ago. Since that time I've heard that Sacramento has variants that will induce tears, laughter, reflex vomiting, sleep, even something suspiciously like agape, brotherly love. God only knows what they'll come up with when they really know what they're doing. At any rate, they sent over a sample for us to test, that and accompa­nying data. I'm afraid that is most probably the target of our burglary."

Alex asked the question. "What does this batch do?"

Skip turned his palm briefly to the ceiling. "Not sure. That was why they sent us the sample. They felt that our proximity to Dream Park might give us some additional testing options. Prelim­inary testing indicates that it is a general emotion intensifier. If this is true, and it is a substance as totally harmless as all prelimi­nary testing indicates, it is an incalculably valuable advantage over our competition. The theft of the sample, and of the printed mat­ter, breaks us wide open." He folded his hands in his lap. "That's most of it."

Harmony sat up in his chair and turned to Griffin. "Well, Alex? What do you think?"

"I think I was right. Industrial espionage. How many people knew the stuff was here, Skip?"

"Maybe five, myself included. Perhaps twice that many in Sacramento."

"Thanks. You saved me my second question. There's a leak, that's for sure. Whether it's electronic or human I can't say now. With twice the people knowing it in Sacramento, it might be twice as likely for the leak to originate there. It would be a neat trick to wait until a sample is transferred here. Then again, it doesn't take a genius to see why I'd rather believe that theory." He sighed.

"Well It's happened. I don't believe the damage is irreversible." Harmony's ears perked up. "Why?"

"I don't think that the thief has left the scene yet."

O'Brien seemed troUbled. "The building was searched. If the thief didn't leave the building he must be one of us. The security men, the psychology staff, and whoever else was here."

"A small group from engineering was still on the fifth."

"Right. We were all routinely searched, so the stuff wasn't on any of us physically, but that doesn't help. It could be hidden in the building."

"Might be, and we're checking on that." Griffin nodded, arrang­ing his thoughts. "I don't think that's it, though. I found some traces in the basement of R&D that suggest that the thief came into the building from Gaming Area A. That is the weakest link in our defenses. We have excellent protection on all outer perime- ters, but between Gaming A and the basement..." He shrugged. "The Garners are so out of touch with reality that they were never considered a serious threat. But the thief used surgical bandage. Garners carry medical kits... Skip, how long ago did the sample arrive?"