“But look over there,” returned Captain Jack Benson.  “You see the ‘Pollard’ taking the wind out of our teeth, don’t you?”

“Yes,” Hal admitted, looking more puzzled.

“Do you think our engines are doing the top-notch of their best?” asked Benson.

“Yes; for Williamson is a crackerjack machinist.  He knows our engines as well as any man alive could do.”

“Do you think it would do any good for you to go below, Hal?”

“I will, if you say so,” offered Hastings.  “Yet there’s another side to it.”

“What?”

“Williamson might get it into his head that I went below because I thought he was making a muddle of the speed.  As a matter of fact, he knows every blessed thing I do about our motors, and Williamson is loyal to the core.”

“I know,” nodded Captain Jack.  “I’d hate to hurt a fine fellow’s feelings.  Yet—­confound it, I do want to win this burst of speed.  It means, perhaps, the quick sale of this boat to the Navy.  If we’re beaten it means, to the Secretary of the Navy, that he already has our best boat, and he might not see the need of buying the ‘Farnum’ at all.”

“Give Williamson two or three minutes more,” begged Hal.  “You might tell Eph, though, to repeat, and repeat, the signal for top speed.  That’ll show Williamson we’re losing.”

Jack Benson walked to the conning tower, instructing Eph Somers in a low tone.

“I’ve signaled twice, since the first time,” Eph replied.  “But here goes some more.”

“I wonder what’s going wrong with our engines, then,” muttered Captain Jack, uneasily.

“It ain’t in careless steering, anyway,” grumbled Eph.  “I’m going as straight as a chalk line.”

“I noticed that,” Captain Jack admitted.

He continued to look worried, for, by this time, the “Pollard” was at least a good two hundred and fifty yards to the good in the lead.

“I’m afraid,” muttered Hal, rejoining Benson, “that I’ll simply have to go below.”

“I’m afraid so,” nodded Jack.  “We simply can’t afford to lose this or any other race to the ‘Pollard.’”

“Williamson knows that fully as well as we do, though,” Hal Hastings went on.  “And Williamson—­”

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.