She’d seen it from the outside, of course. It wasn’t especially mysterious-looking. In fact, it looked exactly like an ordinary old-fashioned boxcar: wooden, not steel, and painted a pale, watery blue. But it had a small door on one side, and now that she looked closely, she saw that it had something painted on it, in faded white paint:

?

Tom waited outside while Kate opened the door and looked.

“Right?” Tom said.

Kate nodded. All that extra energy of his did come in handy sometimes.

“When you’re right,” she said, “you’re right.”

“We should probably talk about this with the Silver Arrow.”

“Maybe. Maybe not, though. It’s disappointingly sensible about things like this.”

They went back up to the engine together.

WELL?

“We’re backing up.” Tom put the engine in reverse.

WHY?

ARE WE GIVING UP?

“We’re not giving up,” Kate said. “We’re backing up.”

HOW FAR?

“Just enough,” Tom said. “Let’s say a mile.”

“Enough for what?”

“Enough,” Kate said. “Do you trust us?”

There was a pause from the Silver Arrow. A long one. Finally it typed:

yes

“Wow,” Tom said. “I didn’t know you even had a font that small.”

MAYBE WE SHOULD PUT KATE BACK IN CHARGE THOUGH

“No, this is good,” Kate said. “You were right. Tom knew what to do.”

AND I’M ALL FOR ENCOURAGING HIM BUT

“Good.”

After they’d backed up about a mile, Tom brought them to a stop. He gave the engine some steam, and the Silver Arrow started moving forward again. Faster. And faster. Soon they were really moving.

Tom hit the whistle:

FOOOOM! FOOOOOOOOOM!

The chuff-chuff of the engine was in double time and getting even faster, merging into a continuous roar. Kate looked outside. There was no stopping now, even if they wanted to.

“Go, Kate!” Tom shouted.

Kate sprinted back through the train to the mystery car.

“Find something to hang on to!” she called to the animals as she shot through the library.

What she’d seen inside the mystery car were two enormous metal cylinders bolted onto the arms of a massive steel girder shaped like a T. The cylinders were bright unpainted steel and flared out into huge cones pointing backward. It was pretty much impossible to mistake them for anything other than what they were: a pair of rocket engines.

“I knew Uncle Herbert should’ve gotten us a rocket!” Kate said to herself.

Unsurprisingly, the operation of rocket engines wasn’t something that the Silver Arrow had covered in their training sessions. Fortunately, these particular rocket engines didn’t seem too complicated. In between them on the T-shaped support was a single small red button. A label under the button read: PUSH ME THEN RUN AWAY

Kate pushed the button.