206 



SYAIPOSIUM ON AERONAUTICS. 



Fig. i6. Mean free air temperatures above Mount Weather, Va. 



the station being 300 meters higher than the floors of the valleys 

 on either side of the Ridge. Aerial navigation in this turbulent 

 region is considerably more difficult than it would be outside the 

 limits of the region. 



Fig. 17. Temperature distribution in highs observed at Mount Weather. 



