40 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 62 



-2' o 2* 4° 6° 8° 10" 12° 1+" 



Fig. 10. — Wind characteristics. 



Aerofoil R. A. F. 6. 



Velocity 29.85 miles per hour. 



Density of air 0.07608 pound per cubic foot. 

 □ Nat. Phys. Lab. observations. 

 - A Mass. Inst. Tech. observations, model A. 

 O Mass. Inst. Tech. observations, model B. 



(6- 



18" 



