A spasm shook him; his eyes closed for a moment in pain, then opened again. They were febrilely bright.

"Most important of all ... Brian ... the spores. You must find a way ... to destroy them. Go back to Earth ... and awaken man ... to a new, a peaceful, world."

He was silent so long that I cried out, "Doctor!" I couldn't say more.

But he spoke again, and for the last time. "I am sure now ... Brian ... you will find the answer ... in chlorophyll. Keep after it. The fate of all ... mankind ... is in only your...."

And that was all. His eyes closed, then, as if they had finally found peace. I turned away. Maureen covered his face tenderly. She came to my side, and her voice was soft.

"He was right, Brian. You are our leader now. It is up to you to find the antidote for Earth's illness."

I stared at her long and bitterly. My voice must have been harsh.

"I! I, Maureen? Tell me—do you know the formula for chlorophyll? Do I? Does anyone aboard this ship, now he is gone?"

"Don't be upset, Brian. No, we don't—but there's no cause for despair. It, and everything else you need know, is at our disposal. That's why he went to such pains to provide a scientific library for the ship. All man's knowledge lies there, waiting for us to seek it out."