tself accidental-laik, an' it peppered him good
an' proper."

"Why, Rad!" cried Ned. "You didn't tell us about this."

"Well, I were 'shamed ob mah cousin, so I was. Anyhow, I only had salt
an' pepper in de gun--'stid ob shot. I 'spect mah cousin am pretty well
seasoned now. But dat's de only s'picious folks I see, 'ceptin' maybe a
peddler what wanted t' gib me a dish pan fo' a pair ob ole shoes; only
I didn't hab any."

"There are altogether too many strangers coming about here," went on
Tom. "It must be stopped, if I have to string charged electric wires
about the shops as I once did."

They hurried back to the shop where the new powder was kept, and Tom at
once investigated it. Taking the steel box from where it was stored he
carefully removed the several handfuls of excelsior-like explosive. On
the bottom of the box, and with some of it clinging to some of the
powder threads, was a sort of white powder. It had a peculiar odor.

"Ha!" cried Tom, as soon as he saw it. "I know what that is. It's a
new form of gun-cotton, very powerful. Whoever gave it to Koku to put
on my powder hoped to blow to atoms any cannon in which it might be
used. There's enough here to do a lot of damage."

"How is it that it didn't blow your test cylinder to bits?" asked Ned.

"For the reason that the stuff I use in my powder and this new
gun-cotton neutralized one another," the young inventor explained. "One
weakened the other, instead of making a stronger combination. A
chemical change took place, and lucky for us it did. It was just like a
man taking an over-dose of poison--it defeated itself. That's why my
experiment was a failure. Now to put this stuff where it can do no
harm. Is this what that man gave you, Koku?"

"That's it, Master."

There came a tap on the door of the private room, and instinctively
everyone started. Then came the voice of Eradicate, saying:

"Dere's a army gen'men out here to see you. Massa Tom; but I ain't
gwine t' let him in lessen as how you says so."

"An army gentleman!" repeated Tom.

"Yais, sah! He say he General Waller, an' he come on a motor-cycle."

"General Waller!" exclaimed Tom. "What can he want out here?"

"And on a motor-cycle, too!" added Ned. "Tom, what's going on, anyhow?"

The young inventor shook his head.

"I don't know," he replied; "but I suppose I had better see him. Here.
Koku, put this powder away, and then go outside. Mr. Damon, you'll
stay; won't you?"

"If you nee