Then, suddenly, he was brought up with a start. The steady song of the cylinders had given way to an ineffectual popping, and he knew that something had gone wrong. The propeller ceased its revolutions, and the submarine came to a dead stop and rolled helplessly in the swell.
"Something's busted," remarked Dick, sitting up.
Muffled voices could be heard and sounds of movements as though one of the crew were going aft to the engine room.
Sputter, sputter, pop, pop, pop!
Again and again the noise reached Matt's ears, but the motor would not take the spark properly.
After half an hour of this, some one banged a fist sharply against the other side of the door.
"Matt!" called the voice of Gaines.
"Well?" answered the young motorist.
"You'll have to go and fix up the motor. I'll be hanged if I can do it."