"Dirty, of course," she commented disgustedly. "Have you any sand-paper?"

He found a bit after more fumbling, and watched her while she scrubbed the metal points until they were bright. Then she replaced the plug and screwed it into position with a vigorous twist of the wrench.

The boatman had settled back in his place. After that she found a screw-driver and removed the cover from the float-chamber in the carbureter. A brief inspection of this mysterious compartment satisfied her.

"Now spin that fly-wheel," she said abruptly, rising from her knees and moving aside to make room for him.

The boatman spun the fly-wheel, not once, but many times. Twice the engine started, only to stop after a few revolutions.

"It's abominable!" exclaimed the passenger. "What do you propose to do?"

"Nothing, I guess," replied the boatman. "You've done more things now than I ever knew could be done. Don't suppose you damaged anything, do you?"

She glared at him, then turned her scorching glance out upon the river.

"Here comes a boat!" she said suddenly.

The boatman followed the line of her pointing finger and discerned the lights of a craft that was bearing rather closely toward them.