You came down with a rush, young feller, but you went back just as quick." Frank understood instantly.
"Here is a man who saw it!" he cried.

"He will tell you that I am not lying." The engineer turned to the stoker.
"How did he happen to fall ?" he asked.
"He didn't fall," declared the begrimed coal heaver.
"No?
What then--" "'Nother chap jumped on his back and flung him down.

It's wonderful he wasn't killed." Frank was triumphant.

He regarded the engineer and his assistant with a grim smile on his face.
"This is incredible!" exclaimed the engineer.

"Who could have done such a thing ?" "Somebody who came from this room!" rang out Merry's clear voice.
"This shall be investigated!" declared the engineer.