286 



H. MOHN. METEOROLOGY. 



[norw. POL. EXP. 



THE CONSTANCY AND CHANGE OF THE DIRECTION OF THE WINDS. 



We see in the Tables of observations that the direction of the wind is either 

 the same or changes, from one hour of observation to the next. The change goes 

 either with the Sun (veering) or against the Sun (backing). Counting, for each 

 month, the number of cases in which the wind direction from one hour of obser- 

 vation to the next is (1) constant, (2) veering, and (3) backing, and reducing the 

 number of cases to 100, we obtain the following Table. 



Taking the means for the months, seasons and year, we obtain 



