Francesco
de Lana was born in 1631. He became a Jesuit and taught science
at a Roman monastery in Brescia. Inspired by the writings of the
English scientist, Roger Bacon, de Lana carried out research into
flight. His experiments suggested that air is lighter at higher
altitudes. In 1670 he used this information to design a flying boat.
The machine was propelled by a sail and lifted by 4 copper spheres
from which all the air had been pumped. He
speculated that the climbing speed of his airship could be regulated
by using small sacks of sand for ballast.
Francesco
de Lana is credited as being
the first person to design a lighter-than-air craft based on definite
scientific principles. The copper
spheres of the flying boat posed a problem which de Lana could not
solve. If the globes were made thin enough to become lighter than
air, they would collapse under atmospheric pressure as the air from
within was extracted. If they were constructed heavier than air,
they would not lift at all.
