ZitatThe first individual to write in what we would consider a serious, scientific way about the possibility of flight was Roger Bacon, a Franciscan monk who lived from 1214 to 1292. Bacon was a prolific writer and devoted much energy to defending the power of reason and to ridiculing medieval scholasticism and the “magic of alchemy. Those who followed him look upon Bacon as a critically important step in humankind’s emergence from the ignorance of the Dark Ages; considering he had little support around him, he was probably one of the keenest minds of human history. In 1260, Bacon wrote a work on the superiority of reason called De Mirabili Potestate Artis et Naturae (On the Marvellous Powers of Art and Nature). In it he suggests that human reason is so powerful that it could even manage to do something that seems utterly impossible, namely, build a machine that would enable a person to fly. The manuscript—which was not published for nearly three hundred years—then yields two incredible passages.
The first outlines two possible ways in which a person might fly. One is a rough description of what was later to become known as an ornithopter. The other is a more detailed description of a globe filled with “ethereal air.” Having demonstrated that air is a kind of fluid in which less dense objects might float like a ship floats on water, Bacon suggests methods of thinning the air in a globe that will give it buoyancy in air—more than five hundred years before lighter-than-air flight would become a reality. The second remarkable section is even more intriguing, for in it Bacon claims, “There is an an instrument to fly with, which I never saw, nor know any man that hath seen it, but I full well know by name the learned man who invented the same.”
It is possible that Bacon is referring to his fellow Englishman, Eilmer (also known as Oliver) of Malmesbury, a monk who was the first of the so-called tower-jumpers—people who tried to fly by jumping off a high place with winglike contraptions connected to their arms or body. Most of these attempts ended in the death of the jumper, but Eilmer, who jumped in about 1010, some 250 years before Bacon, was reported to have glided about 250 yards (228.5m) and survived a bumpy landing (though he broke both his legs). Eilmer is immortalized in a stained glass portrait in the Malmesbury Abbey, holding his batlike wings (perhaps pre-flight, since he is standing rather erect). If Bacon meant a device used in his own day that flew successfully, it was certainly the best kept secret of the Middle Ages.
Quelle: http://www.century-of-flight.freeola.com/new%20site/frames/myths_frame1.htm