Hot him to open his Gas Fortress to it that way. Then the whole packattacked. It's painted itself red and green and blue and white, ondifferent occasions, but it always goes back to black, sooner orlater. It doesn't like yellow or brown or two-tone. I've a list ofalmost every phoney plate it's ever used. It's even driven the bigfreeways right into towns and fueled up at regular gas stops. Theyoften get its number as it tears away from them, just as the attendantgoes up on the driver's side for his money. It can fake dozens ofhuman voices. They can never catch it afterwards, though, becauseit's souped itself up too well. It always makes it back here to thePlain and loses them. It's even raided used car lotsч"

Jenny turned sharply in her course.

"Sam! The trail is quite strong now. _This_ way! It goes off inthe direction of those mountains."

"Follow!" said Murdock.

For a long time then Murdock was silent. The first inklings ofmorning began in the east. The pale morning star was a whitethumbtack on a blueboard behind them. They began to climb a gentlyslope.

"Get it, Jenny. Go get it," urged Murdock.

"I think we will," she said.

The angle of the slope increased. Jenny slowed her pace to matchthe terrain, which was becoming somewhat bumpy. "What the matter?"asked Murdock.

"It's harder going here," she said, "also, the trail is gettingmore difficult to follow."

"Why's that?"

"There is still a lot of background radiation in these parts," shetold him, "and it is throwing off my tracking system."

"Keep trying, Jenny."

"The track seems to go straight toward the mountains."

"Follow it, follow it!"

They slowed some more.

"I am all fouled up now, Sam," she said. "I have just lost thetrail."

"It must have a stronghold somewhere around hereчa cave orsomething like thatчwhere it can be sheltered overhead. It's the only