Of a sudden Hal stopped short. He half staggered, clutching at a rail,
while his eyes stared and his lips twitched.

“Why—why—there’s Williamson—aft on the deck!” muttered Hastings.

“What!”

Jack, too, wheeled like a flash. Back there in a crowd of cadets stood the
machinist upon whom the submarine boys were depending for the best showing
that the “Farnum” could make.

“Williamson up here!” gasped Hal. “And—”

“That fellow, Truax, all alone with the motors!” hissed Captain Jack.
Then, after a second or two of startled silence:

“Come on, Hal!”

The naval cadets were too much absorbed in watching the race to have
overheard anything. Williamson, too, standing at the rail, looking out
over the water, had not yet discovered that Hal Hastings was up from the
engine room.

Jack Benson stole below on tip-toe, though with the machinery running so
much stealth was not necessary. Right behind him followed Hal.

As the two gained the doorway of the engine room Sam Truax had his back
turned to them, and so did not note the sudden watchers.