74 Messrs. W. N. Shaw and R. W. Cohen. On the Seasonal 



direction in bringing about the second-order effect by any method of 

 direct composition of these curves, but the fact that each of the three 

 groups gives a curve of frequency whose characteristics show this 

 remarkable correspondence with those of the second-order curve, is 

 stifficient evidence that the relative frequency of occurrence of winds 



DIAGRAM 5. 



FREQUENCY CURVES. KEW 1 876 TO 1 884. 



DEC. JAN. FEB. MAR. APR. MM JUN. JUL AUG. SEP. OCT. NOV. DEC. 



14-7 



3.Temper&be.(SE.NYj.) 



from the various quarters plays some part in causing the second-order 

 effect. What this part is is shown in Diagram 6. Fig. 1 gives the 

 curve of mean temperature difference throughout the year, and fig. 2 

 gives the curve which is directly compounded of all the temperature 

 curves for the various winds, so that the effect of relative frequency is 

 eliminated ; fig. 3 is obtained by subtracting the ordinates of fig. 2 from 

 the corresponding ones of fig. 1, and may be taken as representing the 

 effect upon temperature arising from the relative frequency of warm or 

 cold winds. The main features of this curve are the winter maximum 



