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 levers.

The impetus was given, inventors invented, calculators calculated all that could render aerial locomotion practicable.

Bourcart, Le Bris, Kaufmann, Smyth, Stringfellow, Prigent, Danjard, Pomes and De la Pauze, Moy, Penaud, Jobert, Haureau de Villeneuve, Achenbach, Garapon, Duchesne, Danduran, Pariesel, Dieuaide, Melkiseff, Forlanini, Bearey, Tatin, Dandrieux, Edison, some with wings or screws, others with inclined planes, imagined, created, constructed, perfected, their flying machines, ready to do their work, once there came to be applied to thereby some inventor a motor of adequate power and excessive lightness.
This list may be a little long, but that will be forgiven, for it is necessary to give the various steps in the ladder of aerial locomotion, on the top of which appeared Robur the Conqueror.

Without these attempts, these experiments of his predecessors, how could the inquirer have conceived so perfect an apparatus?
And though he had but contempt for those who obstinately worked away in the direction of balloons, he held in high esteem all those partisans of "heavier than air," English, American, Italian, Austrian, French--and particularly French--whose work had been perfected by him, and led him to design and then to build this flying engine known as the "Albatross," which he was guiding through the currents of the atmosphere.
"The pigeon flies!" had exclaimed one of the most persistent adepts at aviation.
"They will crowd the air as they crowd the earth!" said one of his most excited partisans.
"From the locomotive to the aeromotive!" shouted the noisiest of all, who had turned on the trumpet of publicity to awaken the Old and New Worlds.
Nothing, in fact, is better established, by experiment and calculation, than that the air is highly resistant.

A circumference of only a yard in diameter in the shape of a parachute can not only impede descent in air, but can render it isochronous.