The stranger nodded in satisfaction. "When you get back home, bone up on things. But right now you go take a close look at the manifest card on the sides of the second and third cars...."
I jumped to the ground to go back and look at the second and third cars. As I passed the rear of the Diesel I saw why the fireman had not come back to the engine cab. All that was left of him was the lower part of his body. He had slipped, caught one foot and gone under the wheels.
I came to the second car and read the manifest label. My hair stood straight up.
The cars were marked:
Danger
DYNAMITE
High Explosive
The shaggy man was at my side. "You've got questions. But let me ask you one: Ever hear a story about how if you travel back to the time of an ancestor and you let him die you never get born?"
"What about it?" I said.
"It's true," said the shaggy man.