spasmodically, in spite of the success of the plane with its
driving propeller. As to the parachute, the idea was doubtless
inspired by observation of the effect a bird produced by
pressure of its wings against the direction of flight.

Da Vinci's conclusions, and his experiments, were forgotten
easily by most of his contemporaries; his Treatise lay forgotten
for nearly four centuries, overshadowed, mayhap, by his other
work. There was, however, a certain Paolo Guidotti of Lucca,
who lived in the latter half of the sixteenth century, and who
attempted to carry da Vinci's theories--one of them, at least,
into practice. For this Guidotti, who was by profession an
artist and by inclination an investigator, made for himself
wings, of which the framework was of whalebone; these he covered
with feathers, and with them made a number of gliding flights,
attaining considerable proficiency. He is said in the end to
have made a flight of about four hundred yards, but this attempt
at solving the problem ended on a house roof, where Guidotti
broke his thigh bone. After that, apparently, he gave up the
idea of flight, and went back to painting.

One other a Venetian architect named Veranzio. studied da
Vinci's theory of the parachute, and found it correct, if
contemporary records and even pictorial presentment are correct.
Da Vinci showed his conception of a parachute as a sort of
inverted square bag; Veranzio modified this to a 'sort of square
sail extended by four rods of equal size and having four cords
attached at the corners,' by means of which 'a man could without
danger throw himself from the top of a tower or any high place.
For though at the moment there may be no wind, yet the effort of