222 



L. HARGRAVE. 



Fig. 13. 



A fringe of silk is glued to the concave side of the propeller on 

 O and^P so that it is possible to see that the "divide" is approxi- 

 mately^ the position shown in the diagram (Fig. 10). 



_ J 



Fig. 14. 



Kite Q has two propellers superposed at a distance of 8". The 

 ballast tube is 3J" below the under one. This kite shows that a 

 double propeller soaring machine can be balanced in a fore and 

 aft direction as well as, or better than, the single form. 



