d the
convict hulk at Portsmouth.

AIR-TRAVELLING.

It may be generally known, that for some time extraordinary efforts
have been making to discover a method by which locomotion through the
air may be rendered as certain and practicable as locomotion by sea or
land. In this desperate enterprise, of bringing the principle of
aerostation into regular use, certain individuals in Paris have taken
the lead. Our belief, like that of others, is, that plans of this kind
will fail, as they have hitherto done; at the same time, we think it
would be improper to dogmatise on the subject, and will only say, that
if travelling by balloon becomes one of the established things of the
day, so much the better.

With these feelings, we have thought it consistent with our duty as
journalists, not to refuse publicity to an account of what was till
lately doing in Paris to forward practical aerostation--we say,
lately; for we are told by our correspondent, that the operations
towards perfecting the invention have been stopped by orders of the
French government, from an opinion that, if air-travelling were
introduced, it would be injurious to the custom-house, and
denationalise the country. This resolution of the French government is
to be regretted, not less on the score of science, than from the ruin
it has inflicted on the modest means of the ingenious operator. With
these preliminary explanations, we offer the following paper, just as
handed to us by a respectable party conversant with the details to
which he refers.

'The chief difficulty in aero-locomotion, is that of steering; because
the atmosphere seems to present no substantial fulcrum which can be
pushed against. But that this difficulty is not altogether
insurmountable, is evident from the single fact, that birds really do
steer their way through the air. This fact suggests, that a fulcrum is
not necessarily a palpable substance: it may be pliant or movable. For
instance, if we fasten the string of a kite to a ball, this ball,
which represents the fulcrum, being set in motion by the kite, becomes
a movable fulcrum: a child also, holding the string in his hand, runs
from right to left without impeding the motion of the kite, of which
motion he is the movable fulcrum. Absolute stability, therefore, is
not a necessary condition of a fulcrum; it is sufficient that there
be, between the resistant force and the motive force, a difference of
intensity in favour of the forme