g as the current is applied it remains focused
upon that object, no matter what comes between. In the second
border-line condition the power is liberated as a terrific repulsion.

"Third: That the copper is completely transformed into available energy,
there being no heat whatever liberated.

"Fourth: Most important of all, that the X acts only as a catalyst for
the copper and is not itself consumed, so that an infinitesimally thin
coating is all that is required."

"You certainly have found out a great deal about it," replied Crane, who
had been listening with the closest attention, a look of admiration upon
his face. "You have all the essential facts right there. Now we can go
ahead and put in the details which will finish up the plans completely.
Also, one of those points solves my hardest problem, that of getting
back to the earth after we lose sight of it. We can make a small bar in
that border-line condition and focus it upon the earth, and we can use
that repulsive property to ward off any meteorites which may come too
close to us."

"That's right. I never thought of using those points for anything. I
found them out incidentally, and merely mentioned them as interesting
facts. I have a model of the main bar built, though, that will lift me
into the air and pull me all around. Want to see it work?"

"I certainly do."

As they were going out to the landing field Shiro called to them and
they turned back to the house, learning that Dorothy and her father had
just arrived.

"Hello, boys!" Dorothy said, bestowing her radiant smile upon them both
as Seaton seized her hand. "Dad and I came out to see that you were
taking care of yourselves, and to see what you are doing. Are visitors
allowed?"

"No," replied Seaton promptly. "All visitors are barred. Members of the
firm and members of the family, however, are not classed as visitors."

"You came at the right time," said Crane, smiling. "Dick has just
finished a model, and was about to demonstrate it to me when you
arrived. Come with us and watch the...."

"I object," interrupted Seaton. "It is a highly undignified performance
as yet, and...."

"Objection overruled," interposed the lawyer, decisively. "You are too
young and impetuous to have any dignity; therefore, any performance not
undignified would be impossible, _a priori_. The demonstration will
proceed."

* * * * *

Laughing merrily, the four made their way to the te