eared, one by one, into the interior of the ship. Ward began to
run.

It was strictly forbidden for a teacher to enter the dormitory--that
part of the boys' world was completely their own. But he ignored that
ruling now as he raced up the stairs. All he could think of was that
this was the chance to identify the invaders. The boys who had levitated
themselves up to the Saucer would be missing.

He was still exultantly certain of this as he jerked open the doors of
the first three rooms. Each one was empty. And the fourth and fifth, as
well. Frantically, he pulled open door after door, going through the
motions, although his mind told him that it was useless, that all of the
boys, with a Saucer so close, would be out looking at it.

Wait until they returned? He couldn't remain in the dormitory and, even
if he did, when they all came back, how could he find out which boys had
gone up to the ship? They wouldn't be likely to tell, nor would the
others, even if they knew. Aimlessly, he went on opening doors, flashing
his Watcher's light.

Perhaps there would be a clue in one of the rooms. Excited again, he
rapidly checked them, rummaging in closets, picking up their sports
things and their toys. Nothing there. Until he found the book.

It was an odd-looking book, in a language he couldn't read. He looked at
it doubtfully. Was the script simply Cyrillic? Or Hebrew? He stuffed it
into his pocket and glanced around at the walls of the room. Pictures of
athletes, mostly, and a couple of pin-ups. In a drawer, under some
clothing, a French post card. He examined some of the objects on the
dresser.

Then he was looking stupidly at his hand. He was holding a piece of
string with a ring attached to it. And, just as certainly, there was
something attached to the other end. Or it had been. But there was
nothing he could see now. He pulled on the string and it tightened. Yes,
there was a drag on the other end, _but there was nothing he could see
... or feel_.

He tried to reconstruct his actions. He had been pawing among the
things. He had taken hold of the string and had pulled something
attached to the end of it off the table. The thing had fallen and
disappeared--but _where_? It was _still_ tied to the string, but where
was it?

Another dimension, he thought, feeling the hair stand up on his neck,
the sudden riot of his blood as he knew he had found the evidence he
wanted.

He snapped off the light and groped his way rapi