to multiply. In 1742 the Marquis de Bacqueville designed a system of
wings, tried it over the Seine, and fell and broke his arm. In 1768
Paucton conceived the idea of an apparatus with two screws,
suspensive and propulsive. In 1781 Meerwein, the architect of the
Prince of Baden, built an orthopteric machine, and protested against
the tendency of the aerostats which had just been invented. In 1784
Launoy and Bienvenu had maneuvered a helicopter worked by springs. 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. in 1852 came
Letur with his system of guidable parachutes, whose trial cost him
his life; and in the same year came Michel Loup with his plan of
gliding through the air on four revolving wings. In 1853 came
Beleguic and his aeroplane with the traction screws,
Vaussin-Chardannes with his guidable kite, and George Cauley with his
flying machines driven by gas. From 1854 to 1863 appeared Joseph
Pline with several patents for aerial systems. Breant, Carlingford,
Le Bris, Du Temple, Bright, whose ascensional screws were
left-handed; Smythies, Panafieu, Crosnier, &c. At length, in 1863,
thanks to the efforts of Nadar, a society of "heavier than air" was
founded in Paris. There the inventors could experiment with the
machines, of which many were patented. Ponton d'Amecourt and his
steam helicopter, La Landelle and his system of combining screws with
inclined planes and parachutes, Louvrie and his aeroscape, Esterno
and his mechanical bird, Groof and his apparatus with wings worked by