ce people are apt to suppose that science can do
everything; but after all Nature has set bounds to her achievements."

_I_. "Still, we don't know what we can and what we cannot do until we
try."

_G_. "Not always; but in this case I think we know. The celestial bodies
are evidently isolated in space, and the tenants of one cannot pass to
another. We are confined to our own planet."

_I_. "A similar objection might have been urged against the plan of
Columbus."

_G_. "That was different. Columbus only sailed through unknown seas to a
distant continent. We are free to explore every nook and cranny of the
earth, but how shall we cross the immense void which parts us from
another world, except on the wings of the imagination?"

_I_. "Great discoveries and inventions are born of dreams. There are
minds which can foresee what lies before us, and the march of science
brings it within our reach. All or nearly all our great scientific
victories have been foretold, and they have generally been achieved by
more than one person when the time came. The telescope was a dream for
ages, so was the telephone, steam and electric locomotion, aerial
navigation. Why should we scout the dream of visiting other worlds,
which is at least as old as Lucian? Ere long, and perhaps before the
century is out, we shall be flying through the air to the various
countries of the globe. In succeeding centuries what is to hinder us
from travelling through space to different planets?"

_G_. "Quite impossible. Consider the tremendous distance--the lifeless
vacuum--that separates us even from the moon. Two hundred and forty
thousand miles of empty space."

_I_. "Some ten times round the world. Well, is that tremendous vacuum
absolutely impassable?"

_G_. "To any but Jules Verne and his hero, the illustrious Barbicane,
president of the Gun Club."[1]

[Footnote 1: _The Voyage a la Lune_, by Jules Verne.]

_I_. "Jules Verne has an original mind, and his ideas, though
extravagant, are not without value. Some of them have been realised, and
it may be worth while to examine his notion of firing a shot from the
earth to the moon. The projectile, if I remember, was an aluminium shell
in the shape of a conical bullet, and contained three men, a dog or two,
and several fowls, together with provisions and instruments. It was air
tight, warmed and illuminated with coal gas, and the oxygen for
breathing was got from chlorate of potash, while the carbonic