THE MECHANICAL ÆROSTAT.
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.
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.