ment. When that's done, build another
one, and still another, until we've used every scrap of material
available in the valley. By that time maybe we'll have some cars running
and can go to Frederick and other towns for more parts."

Ken's father leaned back in his chair, his eyes closed. "If enthusiasm
could do it, we could look forward to such a structure the day after
tomorrow."

"Maybe enthusiasm _can_ do it," said Professor Larsen quietly. "I
believe the boy is right. We've let ourselves despair too much because
of the fire. We still have the necessary principles in our heads. If Ken
is right, we've got the materials. The only problem is that you and I
are a pair of old, exhausted men, without the necessary enthusiasm and
energy. Perhaps we can borrow enough of that from these boys. I'm in
favor of undertaking it!"

By the light of oil lamps they planned and talked until far past
midnight. There were still no objections to be found outside the labor
problem. When they were through, rough drawings and calculations for the
first projector were finished.

"Such a projector could surely reach well into the stratosphere," said
Professor Larsen. "With the tremendous velocities of the air masses at
those heights, one projector should be able to process hundreds of tons
of atmosphere per day."

"I am wondering," said Professor Maddox, "if we should not make the
reflector parabolic instead of hyperbolic. We may disperse our energy
too widely to be effective at high levels."

"I think not. The parabola would narrow the beam to little more than its
initial diameter and would concentrate the energy more than is required.
With the power Ken speaks of, I believe the hyperbolic form could carry
an effective wave into the stratosphere. We'll make some calculations
for comparison tomorrow."

* * * * *

They authorized Ken to speak with the Sheriff the following day.

"I've been wondering when I'd see some of you people," Johnson said
bluntly. "What are you doing about the mess on the hill?"

"My father thought maybe you'd drop in," said Ken.

The Sheriff shook his head. "It's your move. I just wondered if you had
any ideas, or if this fire had knocked the props out from under you."

"It did, but now we're ready to go, and we need help." Briefly, Ken gave
a description of the projector they planned to build. "Labor is the
problem for us. If we could have all the carpenters in town, and al