"What makes you so certain, lad?"

"Why, we'll beat her just because we've got to do it, sir," Hastings
replied, then hurried below.

"Hal isn't any too sure," muttered David Pollard, restlessly. "Neither
am I. Jake, we have a strong fight to make to-day. Somehow, Rhinds has
managed to put a pretty lively engine in that boat of his. I had an
idea she'd be two or three miles an hour slower."

"Probably we haven't been shown anything like the 'Zelda's' best speed,
yet," replied Farnum, moodily.

Building and trying out submarine torpedo boats is the kind of work to
make many a man's hair turn prematurely white. As success depends
solely upon actual showings made, the anxiety of any builder during a
series of competitive tests in which several makes of boat are entered
can be easily understood.

Messrs. Farnum and Pollard were plainly on tenterhooks that day. They
might well be. Should the Rhinds boat carry away the honors on that
day and on the subsequent days of the present tests, then Farnum and
Pollard, who had their entire fortunes invested in this business, would
have on their hands only so much scrap steel, brass and iron.

Nor would Jack and his comrades fare any better. If the boys were
vanquished, Farnum and Pollard would have no more work for them. No
other submarine company would want the services of losers.

"Keep your nerve to-day, won't you, Benson?" asked Lieutenant Danvers,