"Conjugation!"

" 'Direct conference', I've always called it-but then I use the sloppy old slug language for it. Do you think that would pass on the disease?"

"Think so? I'm sure of it! We have demonstrated, right here in this laboratory, that there is actual exchange of living protein during conjugation. They could not possibly escape direct transmission; we can infect the whole colony as if it were one body. Now why didn't I think of that?"

His words roused out a horrid memory, something about, "Would that my subjects had but one neck-" But I refrained from quoting it. "Don't go off half cocked," I said. "Better try it first. But I suspect that it will work."

"It will, it will!" He started to go, then stopped. "Oh, Mr. Nivens, would you mind very much-I know it's a great deal to ask-"

"What is? Speak up; I'm getting hungry." Actually I was anxious to work out the rest of the other problem.

"Well, would you consider permitting me to announce this method of vectoring in my report this morning? I'll give you full credit, but the general expects so much and this is just what I need to make my report complete." He looked so anxious that I almost laughed.

"Not at all," I said. "It's your department."

"That's decent of you. I'll try to return the favor." He turned away feeling happy and I turned back feeling the same way. I was beginning to like being a "genius".

I waited before reopening the door to our cubicle until I had straightened out in my mind all the main features of the big drop. Then I went in. Mary opened her eyes when I came in and gave me that long heavenly smile. I reached down and smoothed her hair. "Howdy, flame top, did you know that your husband is a genius?"

"Yes."

"You did? You never said so."

"You never asked me."

Hazelhurst gave credit all right; he referred to it as the "Nivens vector". I suppose it was natural that I should be asked to comment, though Dad looked my way first.

"I agree with Dr. Hazelhurst," I started out, "subject to experimental confirmation as outlined. However, he has properly left open for discussion certain aspects which are tactical rather than medical. While it is true that the entire body of titans might be infected from one contact, important considerations of timing-crucial, I should say-" I had worked out my whole opening speech, even to the hesitations, while eating breakfast. Mary does not chatter at breakfast, thank goodness!

"-require vectoring from many focal points. If we are to save a nominal hundred percent of the population of Zone Red, it is necessary that all the parasites be infected at as nearly the same time as possible in order that rescue squads may enter Zone Red after the slugs are no longer dangerous and before any host has passed the point where antitoxin can save him. The problem is susceptible to mathematical analysis-" Sam boy, I said to myself, you old phony, you could not solve it with an electronic integrator and twenty years of sweat. "-and should be turned over to your analytical section. However, let me sketch out the factors. Call the number of vector origins 'X'; call the number of rescue workers who much be dropped 'Y'. There will be an indefinitely large number of simultaneous solutions, with the optimum solution depending on logistic factors. Speaking in advance of rigorous mathematical treatment-" I had done my very damndest with a slipstick, but I did not mention that. "-and basing my opinions on my own unfortunately-too-intimate knowledge of their habits, I would estimate that-"

They let me go right ahead. You could have heard a pin drop, if anybody in that bare-skinned crew had had a pin. The general interrupted me once when I placed a rather low estimate on "X"; "Mr. Nivens. I think we can assure you of any number of volunteers for vectoring."

I shook my head. "You can't accept volunteers, General."

"I think I see your objection. The disease would have to be given time to establish itself in the volunteer and the timing might be dangerously close for his safety. But I think we could get around that-a gelatin capsule with the antitoxin embedded in tissue, or something of the sort. I'm sure the staff could work it out."

I thought they could, too, but I did not say that my real objection was a deep-rooted aversion to any additional human soul having to be possessed by a slug. "You must not use human volunteers, sir. The slug will know everything that his host knows-and he simply will not go into direct conference; he'll warn the others by word of mouth instead." I did not know that I was right but it sounded plausible. "No, sir, we will use animals-apes, dogs, anything large enough to carry a slug but incapable of human speech, and in sufficient quantities to infect the whole group before any slug knows that it is sick."

I went on to give a fast sketch of the final drop, Schedule Mercy, as I visualized it. "We can assume that the first drop-Schedule Fever-can start as soon as we are sure that we will have enough units of antitoxin for the second drop. In less than a week thereafter there should be no slug left alive on this continent."

They did not applaud, but it felt that way. The general adjourned the meeting and hurried away to call Air Marshal Rexton, then sent his aide back to invite me to lunch. I sent word that I would be pleased provided the invitation included my wife, otherwise I would be unable to accept.

Dad waited for me outside the conference room. "Well, how did I do?" I asked him, more anxiously than I tried to sound.

He shook his head. "Sam, you wowed 'em. You have the makings of a politician. No, I think I'll sign you up for twenty-six weeks of stereo instead."

I tried not to show how much I was pleased. I had gotten through the whole performance without once stammering; I felt like a new man.

That ape Satan which had wrung my heart so back at the National Zoo turned out to be as mean as he was billed, once he was free of his slug. Dad had volunteered to be the test case for the Nivens-Hazelhurst theories, but I put my foot down and Satan drew the short straw.

Dad made an issue out of it; he had some silly idea that it was up to him to be possessed by a slug, at least once. I told him that we had no time to waste on his sinful pride. He grew huffy but I made it stick.

It was neither filial affection nor its neo-Freudian antithesis that caused me to balk him; I was afraid of the combination of Dad-cum-slug. I did not want him on their side even temporarily and under laboratory conditions. Not with his shifty, tricky mind! I did not know how he would manage to escape nor what he would do to wreck our plans, but I was morally certain he would, once possessed.

People who have never experienced possession, even those who have seen it, cannot appreciate that the host is utterly against us-with all his abilities intact. We could not risk having Dad against us-and I swung enough weight to overrule him.

So we used anthropoid apes for the experiments. We had on hand not only apes from the National Zoological Gardens but simian citizens from half a dozen zoos and a couple of circuses. I did not select Satan for the job; I would have let the poor beast be. The look of patient suffering on his face made one forget the slug on his back.

Satan was injected with nine-day fever on Wednesday the 13th. By Friday the fever had established; another chimp-cum-slug was introduced into his cage; the two slugs immediately went into direct conference, after which the second ape was removed.

On Sunday the 17th Satan's master shriveled up and fell off-dead. Satan was immediately injected with the antitoxin. Late Monday the other slug died and its host was dosed.

By Wednesday Satan was well though a bit thin and the second ape, Lord Fauntleroy, was on the road to recovery. I gave Satan a banana to celebrate and he took off the first joint of my left index finger and me with no time for a repair job. It was no accident either; that ape was nasty.