lt. "Watch the
visible figures," Kaplan muttered.

Reinhart watched, tense and rigid. For a moment nothing happened. 7-6
continued to show. Then--

The figures disappeared. The machines faltered. New figures showed
briefly. 4-24 for Centaurus. Reinhart gasped, suddenly sick with
apprehension. But the figures vanished. New figures appeared. 16-38
for Centaurus. Then 48-86. 79-15 in Terra's favor. Then nothing. The
machines whirred, but nothing happened.

Nothing at all. No figures. Only a blank.

"What's it mean?" Reinhart muttered, dazed.

"It's fantastic. We didn't think this could--"

"_What's happened?_"

"The machines aren't able to handle the item. No reading can come.
It's data they can't integrate. They can't use it for prediction
material, and it throws off all their other figures."

"Why?"

"It's--it's a variable." Kaplan was shaking, white-lipped and pale.
"Something from which no inference can be made. The man from the past.
The machines can't deal with him. The variable man!"

II

Thomas Cole was sharpening a knife with his whetstone when the tornado
hit.

The knife belonged to the lady in the big green house. Every time Cole
came by with his Fixit cart the lady had something to be sharpened.
Once in awhile she gave him a cup of coffee, hot black coffee from an
old bent pot. He liked that fine; he enjoyed good coffee.

The day was drizzly and overcast. Business had been bad. An automobile
had scared his two horses. On bad days less people were outside and he
had to get down from the cart and go to ring doorbells.

But the man in the yellow house had given him a dollar for fixing his
electric refrigerator. Nobody else had been able to fix it, not even
the factory man. The dollar would go a long way. A dollar was a lot.

He knew it was a tornado even before it hit him. Everything was
silent. He was bent over his whetstone, the reins between his knees,
absorbed in his work.

He had done a good job on the knife; he was almost finished. He spat
on the blade and was holding it up to see--and then the tornado came.

All at once it was there, completely around him. Nothing but grayness.
He and the cart and horses seemed to be in a calm spot in the center
of the tornado. They were moving in a great silence, gray mist
everywhere.

And while he was wondering what to do, and how to get the lady's knife
back to her, all at once there was a bump and the tornado tipped him
over, sprawled ou