at all in the globe or sphere. Propulsion of this airship was to be
accomplished by means of sails, and also by oars.

Lana antedated the modern propeller, and realised that the air would
offer enough resistance to oars or paddle to impart motion to any vessel
floating in it and propelled by these means, although he did not realise
the amount of pressure on the air which would be necessary to accomplish
propulsion. As a matter of fact, he foresaw and provided against
practically all the difficulties that would be encountered in the
working, as well as the making, of the aerial ship, finally coming up
against what his religious training made an insuperable objection. This,
again, is best told in his own words:--

'Other difficulties I do not foresee that could prevail against this
invention, save one only, which to me seems the greatest of them all,
and that is that God would surely never allow such a machine to be
successful, since it would create many disturbances in the civil and
political governments of mankind.'

He ends by saying that no city would be proof against surprise, while
the aerial ship could set fire to vessels at sea, and destroy houses,
fortresses, and cities by fire balls and bombs. In fact, at the end of
his treatise on the subject, he furnishes a pretty complete resume of
the activities of German Zeppelins.

As already noted, Lana himself, owing to his vows of poverty, was
unable to do more than put his suggestions on paper, which he did with
a thoroughness that has procured him a place among the really great
pioneers of flying.

It was nearly 200 years before any attempt was made to realise his
project; then, in 1843, M. Marey Monge set out to make the globes and
the ship as Lana detailed them. Monge's experiments cost him the sum
of 25,000 francs 75 centimes, which he expended purely from love
of scientific investigation. He chose to make his globes of brass,
about.004 in thickness, and weighing 1.465 lbs. to the square yard.
Having made his sphere of this metal, he lined it with two thicknesses
of tissue paper, varnished it with oil, and set to work to empty it of
air. This, however, he never achieved, for such metal is incapable of
sustaining the pressure of the outside air, as Lana, had he had the
means to carry out experiments, would have ascertained. M. Monge's
sphere could never be emptied of air sufficiently to rise from the
earth; it ended in the melting-pot, ignominiously enough, an