revelation. Why they were able to speak Amer-English. Why their ship looked like a Terran one. Why they had been able to 'disrupt' the Earth ships instruments.

He said haltingly, "Why are you here?"

We are familiar with your articles. You alone, Mr. Gray, seem at least to seek understanding. Before we left, we felt it our duty to explain our presence and our purpose—that is, partially.

"Yes," he said. Then, in an attempt to check the conclusion at which he had just arrived, he added, "You are going from the Solar System—leaving your home for a new one?"

There was a long silence.

Finally: As we said, we were going to explain partially our presence and purpose, but obviously you know more than we had thought. Would you mind revealing the extent of your knowledge?

Gray reached to the foot of the bed and took up his night robe; partly because it was chilly, partly to give himself time to consider his answer. Perhaps he shouldn't have said that. He was alone in this small house; he had no knowledge of their intentions toward him.

But he had gone too far now. He said, "Not at all. I am not sure of where we stand, but things should be much clearer, shortly. First of all, your spaceships are tiny. Probably less than ten pounds."

About four, Mr. Gray.

"Which explains why our instruments did not record them; the instruments weren't disrupted, your ships were really too small to register. That's where we made our first mistake. We assumed, for no valid reason, that you were approximately our own size. We were willing to picture you as non-human and possessing limbs, organs, and even senses different from ours; but we have pictured 'aliens', as we've been calling you, as approximately our own size. Actually, you must be quite tiny."

Quite tiny, Markham Gray. Although, of course, the way we think of it is that you are quite huge.

He was becoming more confident now; widely awake, it was less strange to hear the words come from his commonplace home model telviz set. "Our second mistake was in looking for you throughout space," he said softly.

There was hesitation again, then, And why was that a mistake, Markham Gray?

Gray wet his lips. He might be signing his death warrant, but he couldn't stop now. "Because you are not really 'aliens,' but of Earth itself. Several facts point that way. For instance, your ships are minute models of Earth ships, or, rather, of human ships. You have obviously copied them. Then, too, you have been able to communicate with humans too easily. An alien to our world would have had much more trouble. Our ways, our methods of thinking, are not strange to you."

You have discovered a secret which has been kept for many centuries, Markham Gray.

He was more at ease now; somehow there was no threat in the attitude of the other. Gray said, "The hardest thing for me to understand is why it has been kept a secret. Obviously, you are a tiny form of Earth life, probably an insect, which has progressed intellectually as far beyond other insect forms as man beyond other mammals. Why have you kept this a secret from humans?"

You should be able to answer that yourself, Mr. Gray. As we developed, we were appalled by the only other form of life on our planet with a developed intelligence. Why, not even your own kind is safe from your bloodlust. The lesser animals on Earth have been either enslaved by man—or slaughtered to extinction. And even your fellows in the recent past were butchered; man killed man wholesale. Do you blame us for keeping our existence a secret? We knew that the day humans discovered there was another intelligence on Earth they would begin making plans to dominate or, even more likely, to destroy us. Our only chance was to find some refuge away from Earth. That is why we began to search the other stars for a planet similar to this and suitable to our form of life.

"You could have fought back, had we attempted