Make a “flyer” by attaching three vanes to a common centre, mounted
perpendicularly on a pin. These vanes are segments of a circle of which
the obliquity increases as they recede from the centre of motion.
[Illustration: Fig. 152.]
A stand is made to hold it while a cord is wound round the spindle. On
pulling the string, it will ascend.
The vanes must be adjusted angularly for the best effect.