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THE ROYAL SOCIETY OF CANADA 

 Table VI 



A = Mean velocity in miles per hour uncorrected. 



B = Most probable maximum gust velocity. 



C = B smoothed. 



D = Mean velocity in miles per hour corrected to true velocity. 



E = C corrected to true velocity. 



Possible Extreme Gust Velocity 



The equation, 



Vg = 3+l-26Vm 

 only gives the most probable gust velocity occurring during the hour 

 but does not give the highest gust velocity that rriay occur. To obtain 

 some idea of this value, which is very important, the maximum 

 velocities given under each mean velocity were plotted against the 

 number of times that they occurred and a smooth freehand curve 

 drawn through them. The point where the curve cuts the line giving 

 one as the number of times that the velocity is likely to occur, gives 

 the highest gust velocity that is possible. 



By this method the following values (Table VII) were obtained 

 for the possible extreme maximum velocity occurring in a gust for a 



' M. O. 180 of the London Meteorological Office, p. 40. 



