Of all the men who attacked the flying problem in the 19th century, Otto Lilienthal was easily the most important. ... It is true that attempts at gliding had been made hundreds of years before him, and that in the nineteenth century, Cayley, Spencer, Wenham, Mouillard, and many others were reported to have made feeble attempts to glide, but their failures were so complete that nothing of value resulted.
Otto LilienthalOf all the men who attacked the flying problem in the 19th century, Otto Lilienthal was easily the most important. ... It is true that attempts at gliding had been made hundreds of years before him, and that in the nineteenth century, Cayley, Spencer, Wenham, Mouillard, and many others were reported to have made feeble attempts to glide, but their failures were so complete that nothing of value resulted.
Otto LilienthalAll flight is based upon producing air pressure, all flight energy consists in overcoming air pressure.
Otto LilienthalBut we must admit the possibility that continued investigation and experience will bring us ever nearer to that solemn moment, when the first man will rise from earth by means of wings, if only for a few seconds, and mark that historical moment which heralds the inauguration of a new era in our civilization.
Otto Lilienthal