was wrong with Red and I decided to watch him carefully.

"Your scales are cockeyed," Red said. "I feel fine. Never felt better, in fact. Except that I'm lonesome ... not that I don't enjoy your company, pal, ole pal, but I'd like Dollie's better."

Something on the far side of the room caught my eye. It was along the glass partition between the lab and the living room. It might have been a reflection of some sort, because the sun was up and its beams were coming right through the transparent roof at that moment. But for a fleeting instant I thought I saw a figure there. A tall, shapely, black-haired girl, dressed in a flowing robe of orange. The next instant she was gone.

I said I thought it might be a reflection, but I was pretty sure it wasn't. "Red," I said. "We've got company."

"Huh?"

"I'm sure of it, Red. There's somebody else here besides us."

"There's no one else. You're crazy." Red looked around the room. Then he looked at me. His gaze was sharp and penetrating.

"You can't see it now," I said. "But I'm sure I saw something. A woman. Over there." I pointed to where I'd seen the thing that might have been a reflection.

"Maybe you'd better lie down, Jay. You've been working too hard. A year out on this rock could make a man see King Solomon's harem."

"No, Red," I said. "Those funny things we saw, your book pages turning; the cockeyed balance; maybe your loss of weight. They aren't natural. Something is here and what I just saw makes me think it's human and it's trying to get in touch with us."

Red's stomach muscles squeezed with laughter and he held onto a guard rail to keep from being sent across the room by the exertion.

"What I saw was a woman, Red," I went on.

Red laughed out loud and hung on again. "I could use a babe," he said. Suddenly he jerked. "Who hit me?" he asked. Across his face was a red welt, the shape of a woman's hand.

We called them "manifestations" after that and Red called her his ghost sweetheart, although the slap had convinced him it wasn't a ghost. Red's getting slapped was the first indication that perhaps this thing did have matter of some sort, but its ability to remain invisible made it appear that the matter wasn't the ordinary kind.

Finally I came up with some sort of an answer. It was just a crazy idea and there was no way to prove that I was right. I tried to explain it to Red, who didn't know much about atomic physics, but he seemed to get the idea.

"You see, Red, it could be negative matter," I explained.

"What's that?"

"Well, you know what an electron is, I suppose, a negatively charged sub-atomic particle?"

Red nodded.

"And a proton, which is positively charged?"

Again he nodded.

"Well, scientists have learned that there could be positive electrons, as well as negative, and negative protons. In other words each sub-atomic particle has a 'minus quantity' counterpart."

"You're saying it, I'm believing it," said Red. "A guy's gotta believe something."

"Well, this leads to a great deal of speculation. If these minus quantities got together they might form a minus matter."

"You've got me in a hole, so I'm minus too."

"You don't have to understand it, but try to imagine that two universes could exist side by side, one minus, one plus, and that neither could be aware of the other. Every star, every planet and every speck of matter could have its counterpart, but neither would be aware of that counterpart's existence."

Red grinned and shook his head. "Crazy," he said.

"Yes, crazy. But dig this, supposing that some sixth sense made it possible for one of our minus counterparts to get in contact with us through extra-sensory perception."

"How'd they do it?" Red asked.

"I don't know. We don't know how to do it, but it may be that our scientific progress wouldn't keep abreast of each other. We might know more than our minus counterparts in