The stoker uttered a shout and ran toward the foot of the ladder, expecting to find Frank laying there, severely injured or killed. He was astounded when he saw the ready-witted youth grasp the grating, swing in, strike the ladder, cling and slide.

Down Frank came with a rush, but he did not fall. He landed in the stoke-hole without being severely injured. He was on his feet in a twinkling, and up that ladder he went like a cat.

His assailant had darted up the ladder above and disappeared. Merry reached the grating from which he had been hurled, and then he ran up the other ladder.

He was soon in the engine-room.

In that room there was no excitement. The machinery was sliding and swinging in a regular manner, while the engineer sat watching its movements, talking to an assistant. Oilers and cleaners were at work.

"Where is he?" cried Frank, his voice sounding clear and distinct.

They looked at him in amazement.

"What's the matter?" asked the engineer, coming forward.

"I was attacked from behind and thrown into the stoke-hole," Merry explained. "The fellow who did it came in here."

"Thrown into the stoke-hole?"