434 



Results of Makerstoun Obseevations, 1844. 



Annual Variation of the Mean Pressure of Wind when blowing. — The annual variation of the mean 

 pressure of wind, ohtained by dividing the sums of pressures observed, by the whole number of observations, has 

 been already considered. If, however, we divide the sums of pressures observed by the number of observations 

 for wliich a pressure of 0-1 lb. or more was observed, we obtain the means of pressures for the time which the 

 wind blew. The sums of pressure for each montli from Table XXXIII. are as follow : — 



Jan. 



lb. 



223-4 



Feb. 



lb. 



225-0 



Illarch. 



lb. 

 323-9 



April, 

 lb. 



255-2 



Way. 

 lb. 



127-4 



June, 

 lb. 



301-9 



July, 

 lb. 



100-7 



Aug. 

 lb. 



241-6 



Sept. 

 lb. 



201-9 



Oct. 



lb. 



367-2 



Nov. Dec. 



lb. lb. 



396-3 57-5 



Dividing these quantities by the number of times which the wind blew in the respective months we have 

 lb. lb. lb. lb. lb. lb. lb. lb. lb. lb. lb. lb. 



0-96 0-73 0-85 069 0-46 0-75 0-33 0-56 0-46 0-80 0-86 0-33 



These means show generally that the pressure of the wind was least about the warmest quarter and greatest 

 al)0ut the coldest quarter of 1844. The mean for December is an exception to the generality of the result 

 for 1844. 



The mean pressure with which the wind blew in 1844 = 0665 lb. 



TABLE XXXIV.— Sums of the Pressures of the Wind in Table XXXIII., resolved into the Four 

 Cardinal Points of the Compass, together with the Value and Direction of the Resultant, for each 

 Month, for each of the Meteorological and Astronomical Quarters, and for the Year 1844. 



Spring for the meteorological quarters = March, April, May ; 

 ruary, March, April. 



and for the astronomical quarter = Fc 



