observed Bob. "But did you have a
good dinner with the colonel?"

"Listen to him, would you!" protested Ned. "All he can think of is
eating!"

"Cut it out!" growled Bob, as Ned poked him in the ribs. "I just
wanted to know what sort of feed they give the officers."

"Oh," said Jerry significantly. "Merely an academic interest, I
suppose."

"Sure!" assented Bob. "That's all."

"Well, the dinner was very good, though I cannot say that I remember
what I ate," confessed the professor. "I was thinking too much of
something else."

"Do you mean you were puzzled as to how to study the effect of the
noises of the French battlefields on grasshoppers and crickets?" asked
Jerry.

"No," and the professor shook his head. "This is an altogether
different problem. It is, as I might call it, the problem of two
girls."

"Two girls!" cried the three Motor Boys in a chorus. "Two girls?"

They looked at the little professor, whose eyes, mildly blinking
behind his strong glasses, regarded the lads curiously.

"Two girls," repeated the little scientist. "The problem I have to
solve concerns two girls."

CHAPTER V

MORE GIRLS

Ned, Bob and Jerry looked at one another. Then they turned their
glances on the professor.

"Whew!" softly whistled Jerry. "Can it be possible that our dear
friend is in love--and with two girls at once? This is getting
serious!"

It would have been had Jerry's diagnosis been correct. But it was
wrong, as was proved a moment later, when the professor, with a sigh,
resumed his narrative.

"Yes," he said, "I am much concerned over two girls--young ladies I
suppose would be the more proper designation. I have never seen either
of them."

Jerry breathed more freely, and so did his chums. Clearly if the
professor had not seen the two girls he could not be in love with
them. And the professor in love was something unthinkable. He never
would have remembered, from one day to the next, the name of the
favored lady.

"And, boys," went on Professor Snodgrass, "I think you will agree with
me that it is quite a problem to try to find in Europe, at this
particular time, two girls I have never seen, that I may deliver to
them a small fortune, and claim one myself."

"Say, this is getting worse and more of it!" cried Ned. "What does it
all mean, Professor? Are you in earnest about these girls and the
effect of war noises on insects?"

"I am in earnest about both problems--never more so," was the