y transferred, you know."

"If Cantor found the chance, you might last only long enough to
be transferred back to civil life," Dan warned him. "Dave, I
wish you would really be more on your guard against the only enemy,
so far as I know, that you have."

"I'm not interested in Cantor," retorted Dave. "It would do me
a heap more good to know what reply General Huerta will finally
make to the American demand for satisfaction over the Tampico
incident."

"Huerta won't give in," Dan predicted. "If he did, he would he
killed by his own Mexican rabble."

"If Huerta resists, then he'll have to fight," Dave exclaimed,
warmly.

"And if he fights most of the Mexicans will probably stand by
him," Dalzell contended. His only hope of saving his own skin
lies in provoking Uncle Sam into sending a spanking expedition.
At the worst, Huerta, if badly beaten by our troops, can surrender
to our commander, and then he'll have a chance to get out of Mexico
alive. If Huerta gave in to us, he would have all the Mexican
people against him, and he'd only fall into the hands of the rebels,
who would take huge delight in killing him offhand. It's a queer
condition, isn't it, when Huerta's only hope of coming out alive
hangs on his making war against a power like the United States."

"Open for callers?" inquired Lieutenant Trent's voice, outside
Dan's door.

"Come in, by all means," called Ensign Dalzell.

Lieutenant Trent entered, looking as though he were well satisfied
with himself on this warm April day in the tropics.

"You look unusually jovial," Dan remarked.

"And why shouldn't I?" Trent asked. "For years the Navy has been
working out every imaginable problem of attack and defense. Now,
we shall have a chance to apply some of our knowledge."

"In fighting the Mexican Navy?" laughed Dave.

"Hardly that," grinned the older officer. "But at least we shall
have landing-party practice, and in the face of real bullets."

"If Huerta doesn't back down," Dave suggested.

"He won't," Danny Grin insisted. "He can't---doesn't dare."

"Do you realize what two of our greatest problems are to-day?"
asked Lieutenant Trent.

"Attack on battleships by submarines and airships?" Dave inquired,
quietly.

"Yes," Trent nodded.

"Huerta hasn't any submarines," Dan offered.

"We haven't heard of any," Trent replied, "Yet how can we be sure
that he hasn't any submarine craft?"

"He has an airship or two, though, I believe," Dav