l alarm through the
police."

"Oh, I don't know what I'd done if you hadn't come to help me!"
exclaimed Mrs. Damon.

"Just you leave it to me!" said the young inventor, cheerfully.
"I'll find Mr. Damon!"

But, though he spoke thus confidently, Tom Swift had not the
slightest notion, just then, of how to set about his difficult
task. He had had hard problems to solve before, so he was not
going to give up this one. First he wanted to think matters out,
and arrange a plan of action.

He and Ned made a careful examination of the grounds of the Damon
homestead. There was little they could learn, though they did find
where an airship had landed in a meadow, not far away, and where
it had made a flying start off again.

Carefully Tom looked at the marks made by the wheels of the
airship.

"They're the same distance apart as those on the Eagle," he said
to his chum, "and the tires are the same. But that isn't saying
anything, as lots of airships have the same equipment. So we won't
jump to any conclusions that way."

Tom and Ned interviewed several of the neighbors, but beyond
learning that some of them had heard the throbbing of the midnight
airship, that was as far as they got on that line.

There was nothing more they could do in Waterford, and, leaving
Mrs. Damon, who had summoned a relative to stay with her, the two
chums made a quick trip back through the air to Shopton. As
Eradicate came out to help put away the monoplane Tom noticed that
the colored man was holding one hand as though it hurt him.

"What's the matter, Rad?" asked the young investor.

"Oh, nuffin--jest natcherly nuffin, Massa Tom."

But Eradicate spoke evasively and in a manner that roused Tom's
suspicions.

"Boomerang, your mule, didn't kick you; did he?"

"No, sah, Massa Tom, no sah. 'Twern't nuffin laik dat."

"But what was it? Your hand is hurt!"

"Well, Massa Tom, I s'pose I done bettah tell yo' all. I'se had a
shock!"

"A shock?"

"Yas, sah. A shock. A lickrish shock."

"Oh, you mean an electrical shock. That's too bad. I suppose you
must have touched a live wire."

"No, sah. 'Twern't dat way."

"How was it, then?"

"Well, yo' see, Massa Tom, I were playin' a joke on Koku."

"Oh, you were; eh? Then I suppose Koku shocked you," laughed Tom.

"No, sah. I--I'll tell you. Dat giant man he were in de telefoam
boof in de pattern shop--you know--de one where yo' all been
tryin' to make pishures."

"Yes, I know. Go on!"