"Do you know anything about surgery?" queried Matt.

Glennie shook his head.

"Then it's up to me," said Matt, leaving the periscope chamber.

There was a chest in the torpedo room well stocked with everything necessary in the medicine line, also with lint, bandages, and splints. Selecting a set of splints and bandages, Matt returned to the periscope room.

Glennie and Carl had already stripped the water-soaked flannel shirt from the injured man, and Matt, Dick, and Glennie at once got busy.

It was a painful piece of work. While Glennie held the man down on the locker by the shoulders, Dick pulled at the arm, Matt pressing his hands about the fracture so that he might know when the bones got into place.

The patient groaned and yelled, for the pain must have been terrific.

"There you are, Dick," said Matt suddenly. "Now hold it that way until I get it bound up."

Adjusting the splints, Matt wound them rapidly with bandages, and presently had the arm rigidly in the cast.

The work had required some time, and when it was finished, Speake turned from the periscope table.