anything else to do when I saw them
confronting me. So I yelled that my machine was a new product of the
war, and that unless they did exactly as I said I would at once
destroy them, even down to their finger nails, by a blast of terrible
fire from the machine. Fortunately they understood my very poor
German, mixed with English as it was."

"Yes, very fortunately," said the lieutenant. "We saw them drop their
guns and raise their hands, and couldn't understand. But your
machine, harmless as it is, doubtless impressed them as very
dangerous."

When Ned, Bob, and Jerry, as well as the others, looked at the
apparatus, they could understand why an ignorant man, accustomed to
obey and do no thinking, took the picture machine for some terrible
engine of war. The Motor Boys themselves had not seen it before, as
the professor carried it in sections in his luggage, and had only
fitted it together and used it that day.

It consisted of a black box, with numerous wires, wheels, levers and
projecting tubes. These latter contained lenses and shutters, but the
Germans must have imagined devastating fire could spout from them. And
so they had surrendered.

"But I can't understand why the others in the trenches didn't open
fire on you," said the officer.

They learned, later, the reason for this. It was because the Germans
had retired from that particular part of the line. Whether for
strategic reasons, or otherwise, could not be learned, but the three
prisoners admitted that they, alone, had been left in the trench.

Their orders were to remain quiet, and not to attack, but if the
Americans came out of their trenches in force the German sentries were
to fire their rifles, as many hand grenades and machine-gun rounds as
possible, and then retreat, if they could, to the next line of
trenches.

But when Professor Snodgrass approached the lines alone, the Germans,
instead of firing, thought they would capture him, and so the trio
advanced stealthily on the scientist. The result has been seen.

"Well, it was a great piece of work," declared the lieutenant. "Not
only the capture, but because we learned that the Germans are falling
back. This may change our plans somewhat. I must report to
headquarters. And you, Professor Snodgrass, had better come with me."

"But what about my insects?"

"They will have to wait, I'm afraid. Besides, there will be no heavy
firing now. Later--well, I'm afraid I can't tell you of that now. It's