In 1808 there were the attempts at flight by the Austrian Jacques Degen.
In 1810 came the pamphlet by Denian of Nantes, in which the principles of "heavier than air" are laid down.

From 1811 to 1840 came the inventions and researches of Derblinger, Vigual, Sarti, Dubochet, and Cagniard de Latour.

In 1842 we have the Englishman Henson, with his system of inclined planes and screws worked by steam.

In 1845 came Cossus and his ascensional screws.

In 1847 came Camille Vert and his helicopter made of birds' wings.