Along with the invention of the flying machine, da Vinci took into acount the safety aspect of flying.  He imagined a linen tent of which all the apertures have been stopped up that a man would hang from and coast to the ground with ease and free of injury.  It is now obvious that the pyramid structure that he used is not the best for a parachute but in his time it was still an important idea because early flying machine's were probably very unstable and failed frequently.  Compared to da Vinci's version, a modern day parachute is much more reliable, but this was still a worthy start.

    "If a man have a tent made of linen of which the apertures have all been stopped up, and it be twelve braccia across and twelve in depth," Leonardo wrote, "he will be able to throw himself down from any great height without suffering any injury."