eclipsed most of the time. And four thousand miles is a
good way off to see a moon even two hundred feet in
diameter.

Small though we made them on paper, these two-
hundred-foot moons were still too much for us. Of course
we meant to build them hollow. But even if hollow there
must be some thickness, and the quantity of brick would
at best be enormous. Then, to get them up! The pea-
shooter, of course, was only an illustration. It was
long after that time that Rodman and other guns sent iron
balls five or six miles in distance,--say two miles, more
or less, in height.

Iron is much heavier than hollow brick, but you can
build no gun with a bore of two hundred feet now,--far
less could you then. No.

Q. again suggested the method of shooting oft the
moon. It was not to be by any of your sudden explosions.
It was to be done as all great things are done,--by the
gradual and silent accumulation of power. You all know
that a flywheel--heavy, very heavy on the circumference,
light, very light within it--was made to save up power,
from the time when it was produced to the time when it
was wanted. Yes? Then, before we began even to
build the moon, before we even began to make the brick,
we would build two gigantic fly-wheels, the diameter of
each should be "ever so great," the circumference heavy
beyond all precedent, and thundering strong, so that no