"What's the matter?" Reinhart said sharply. Sherikov floundered. "You know how these things are. I've taken my crew off it and tried robot workers. They have greater dexterity, but they can't make decisions. This calls for more than mere dexterity. This calls for--" He searched for the word. "--for an _artist_." Reinhart's face hardened. "Listen, Sherikov. You have eight days left to complete the bomb. The data given to the SRB machines contained that information. The 7-6 ratio is based on that estimate. If you don't come through--" Sherikov twisted in embarrassment. "Don't get excited, Commissioner. We'll complete it." "I hope so. Call me as soon as it's done." Reinhart snapped off the connection. If Sherikov let them down he'd have him taken out and shot. The whole war depended on the ftl bomb. The vidscreen glowed again. Reinhart snapped it on. Kaplan's face formed on it. The lab organizer's face was pale and frozen. "Commissioner, you better come up to the SRB office. Something's happened." "What is it?" "I'll show you." Alarmed, Reinhart hurried out of his office and down the corridor. He found Kaplan standing in front of the SRB machines. "What's the story?" Reinhart demanded. He glanced down at the reading. It was unchanged. Kaplan held up a message plate nervously. "A moment ago I fed this into the machines. After I saw the results I quickly removed it. It's that item I showed you. From histo-research. About the man from the past." "What happened when you fed it?" Kaplan swallowed unhappily. "I'll show you. I'll do it again. Exactly as before." He fed the plate into a moving intake belt. "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.