are described
are calculated to give entirely erroneous ideas about the laws of
motion. Nothing could be more amusing, but at the same time nothing more
scientifically absurd, than the story of the dead dog Satellite, which,
flung out of the travelling projectile, becomes a veritable satellite,
moving always beside the voyagers; for, with whatever velocity the dog
had been expelled by them, with that same velocity would he have
retreated continually from their projectile abode, whose own attraction
on the dog would have had no appreciable effect in checking his
departure. Again, the scene when the projectile reaches the neutral
point between the earth and moon, so that there is no longer any gravity
to keep the travellers on the floor of their travelling car, is well
conceived (though, in part, somewhat profane); but in reality the state
of things described as occurring there would have prevailed throughout
the journey. The travellers would no more be drawn earthwards (as
compared with the projectile itself) than we travellers on the earth are
drawn sunwards with reference to the earth. The earth's attracting force
on the projectile and on the travellers would be equal all through the
journey, not solely when the projectile reached the neutral point; and
being equal on both, would not draw them together. It may be argued that
the attractions were equal before the projectile set out on its journey,
and therefore, if the reasoning just given were correct, the travellers
ought not to have had any weight keeping them on the floor of the
projectile before it started, 'which is absurd.' But the pressure upon
the floor of the projectile at rest is caused by the floor being kept
from moving; let it be free to obey gravity, and there will no longer be
any pressure: and throughout the journey to the moon, the projectile,
like the travellers it contains, is obeying the action of gravity.
Unfortunately, those who are able to follow the correct reasoning in
such matters are not those to whom Jules Verne's account would suggest
wrong ideas about matters dynamical; the young learner who _is_ misled
by such narratives is neither able to reason out the matter for himself,
nor to understand the true reasoning respecting it. He is, therefore,
apt to be set quite at sea by stories of the kind, and especially by the
specious reasoning introduced to explain the events described. In fine,
it would seem that such narratives must be valued for t