"I thought it was odd I should dream about my husband," she said. "I'll believe you, because I don't know how I got here and you do look like the Harry I used to know, before he went all high scientific surgeon and no time for fun." She curved more fully than she had when she was eighteen, but there was neat symmetry to her sine formulae, and she still had blonde hair. Her perfume was the same as the one in the lab I had been smelling all day, it was now reaching me at high amperage. So that was the key, the evocative power of smell association. I sniffed deeply at the perfume in appreciation. "Like it?" Kate asked, wriggling. "Only for its scientific values," I said. "It suggests a most valuable line of research." "I'm in favor," she said, and pressed me to the bed. "Your husband is coming!" I shouted, and it worked. She disappeared. Presumably she woke up in her own probability time-space. And no doubt Kate's reflexes by now were trained to snap her awake and away at the suggestion that her husband was around. It was highly improbable that Kate would alter much. I got up to make myself some coffee. There was no point in wasting sleep without a plan. Clearly, I had to take the pills and fix the appropriate smell in my mind, and when I woke up I would drag the proper slice of another probability with me. And then I would interview the me who had solved the ultra-uranium heavy element equation. And the bomb to end all bombs would be perfected. The test was ready, waiting for me to say, "Let's go, boys. We know what will happen this time." But there was, it struck me, the difficulty of finding the right scent to evoke the right probable me. * * * * * I collected all the toothpaste, deodorant, shaving stick, aftershave lotion I could find in the bathroom and started on the toothpaste. I inhaled deeply and lay down, with the first tube on my chest. But after the coffee, I slept very briefly, and when I looked up there was only a toothbrush on the carpet. It was not mine in this world and I had no idea whose it was, or rather which probable me it belonged to. But at least this established the principle. The smell produced the object--and, if I went deep enough in sleep, it would produce the whole Jones. I dressed quickly and went out for a walk in the night air, breathing deeply and memorizing every scent I came across. Then I went back to the apartment, sniffed hard at the row of personal unguents, and lay down to sleep. When I woke up, it was morning and the room was full of people. There were about a dozen of me, some wearing very odd clothes, some scowling, others grinning unbecomingly, and some looking just plain stupid.