ace of the advancing body (in the nature of an _eddy_,
as it is termed in water), might and no doubt would, to some extent
(though perhaps but slightly) affect the figure of that part, in a
manner, however, calculated rather to aid than to impair the general
design in view,

Another error of more universal prevalency, because of a more
superficial character, regards the condition of the Balloon as
affected by the currents of air, in and through which it might have
to be propelled. The arguments founded upon such a view of the case,
generally assume some such form as the following--"It is true you can
accomplish such or such a rate of motion; but that is only in a room,
with a calm atmosphere, or with a favourable current of wind. In the
open air, with the wind at the rate of twenty or thirty miles an hour,
your feeble power would be of no avail. You could never expect to
direct your course _against_ the wind, and if you were to attempt
it and the wind were strong, you would inevitably be blown to pieces
by the force of the current." Now this argument is equally nought with
the preceding. The condition of the Balloon, as far as regards the
exercise of its propulsive powers, is precisely the same whether the
wind be strong or gentle, with it or against it. In neither case would
the Balloon experience any opposition or resistance to its progress
but what _itself_, by its _own_ independent motion, created;
and that opposition or resistance would be exactly the same in
whatever direction it might be sought to be established. The Balloon,
passively suspended in the air, without the exercise of a propulsive
power, experiences no effects whatever from the motion of the
atmosphere in which it is carried, however violent; and the
establishment of such a propulsive power could never subject it to
more than the force itself, with which it was invested. The _way_
which the Balloon so provided would make through the air would always
be the same, in whatever direction, or with whatever violence the wind
might happen to blow; and the condition of the Balloon would always be
the same that was due to its _own independent_ rate of motion,
without regard to any other circumstances whatever. If it was
furnished with the means of accomplishing a rate of motion equal to
ten miles an hour, it would experience a certain amount of atmospheric
resistance due to that rate; and this amount of resistance with
all its concomitant consequences, neith