“When you apply the brakes, friction on the brake linings makes the backing plate heat up. But if it’s weakened by rust, the heat can twist it and . . .”

“How much for new plates?” asked Jack.

The mechanic switched off his lamp and turned toward the counter where the clerk responsible for parts was standing.

“Peter!” he called. “How much is a backing plate for this ’71 bus?”

“Around thirty-five dollars each,” the clerk replied. “Want me to check?”

“No. But are you sure they’re in stock?”

“Quite sure, yes.”

The mechanic explained, “It’d cost you seventy dollars for the two and about fifty for labour.”

“That’s a lot,” said Jack. “Is it absolutely necessary to change the plates?”

“Depends where you’re going,” said the mechanic.

Jack hesitated.

“We’re travelling the Oregon Trail,” he said.

The mechanic looked pensively at each of them in turn.

“You’re going to follow the Oregon Trail?”

“Yes,” said Jack.

“You’re going to cross the desert and the Rockies?”

“ Yes . . .”

“In the old Volks?”

“All right,” said Jack, “I get it. Put in new backing plates and if you notice any other defective parts, replace them, too.”

An hour and a half later, they were driving west along route 70.

“The motor’s running well,” said Jack. “Can you hear it?”

“Yes, it’s very smooth,” said the girl.

“And the brakes are solid. No vibrations. Shall I do a test? A panic stop?”

“Not now,” she said. “There’s a car right behind us.”

The man looked in the rearview mirror.

“You’re right,” he acknowledged.

“I’d say the old Volks is in tip-top shape,” she said.

He took a chocolate cookie from the bag that he kept beside the seat.

“And what about you? How are you?” he asked with his mouth full.

“Very well.”

“But I mean, are you happy?”

“I’ve everything I need,” she said.

He gave her time to explain herself and at length she said, “When we’re on the road I’m very happy.”

XVIII

The Oregon Trail

They didn’t stay long on route 70. Once they arrived at Topeka, Kansas, they headed northwest toward the Big Blue River, one of the first waterways the 1840 emigrants had had to cross, and from there they drove back onto Interstate 80.

Through Nebraska, route 80 closely followed the Oregon Trail, in some places joining it.

All the information they needed could be found in The Oregon Trail Revisited. Not only did the book tell them the location of the old trail and how to get there, but it also provided data on each of the historic sites, even quoting passages from diaries the emigrants had kept during their journey.

But Jack and the girl liked the book for another reason: the author’s fatherly attitude. For instance, when he said, “Follow such-and-such a route as far as an old barn, take the dirt road, cross a railway track, turn left and drive to the stream, then leave your vehicle and walk a hundred and fifty paces through the grass in a southerly direction, and at that point take a good look at the ruts in the field there: that’s the Oregon Trail . . .” When he gave these very detailed instructions, the author would also add that you must be careful at the level crossing because the signals were faulty, or he might advise you to wear boots in the fields because of the rattlesnakes.