NO. 17.] 



WIND. 



291 



The horizontal row "Mean" in the Table contains the direct means for 

 the three or two years of observation. The horizontal row "Sm." gives a 

 smoothed series of numbers, computed from the formula 



h = 



Pa + % + Pc 



bh being the smoothed value for the respective hour, b the value in the 

 column "Mean", a and c the values for the adjacent hours of observation, 

 Pa, Pb and Pc the respective weights, taken proportional to the numbers of 

 observations. 



The Table shows that there is in each month a remarkably well-defined 

 diurnal period in the velocity of the wind. From the table and diagrams, I 



