"Then how does it kill?"

"By means of a concentrated charge of electricity which is shot from
the barrel with great force. You can't see it, yet it is there. It's
just as if you concentrated a charge of electricity of five thousand
volts into a small globule the size of a bullet. That flies through
space, strikes the object aimed at and--well, we'll see what it does
in a minute. Mr. Jackson, just put that steel plate up in front of
the scarecrow; will you?"

The engineer proceeded to put into place a section of steel armor-
plate before the stuffed figure.

"You don't mean to say you're going to shoot through that, do you?"
asked Ned in surprise.

"Surely. The electric bullets will pierce anything. They'll go
through a brick wall as easily as the x-rays do. That's one valuable
feature of my rifle. You don't have to see the object you aim at. In
fact you can fire through a house, and kill something on the other
side."

"I should think that would be dangerous."

"It would be, only I can calculate exactly, by means of an automatic
arrangement, just how far the charge of electricity will go. It
stops short just at the limit of the range, and is not effective
beyond that. Otherwise, if I did not limit it and if I fired at the
scarecrow, through the piece of steel, and the bullet hit the
figure, it would go on, passing through whatever else was in the