326 



(2) 



r,, = — 0.168 r„ = + 0.782 r,, = + 0.300 

 ,•,,=: — 0.820 )•„ = + 0.014 r„ = — 0.398 

 r„ = - 0.508 r,[ = + 0.323 

 r^^ = _^ 0.354 r,, = + 0.624 r,, = — 0.635 

 /•„ = ~ 0.061 /■„ =: + 0.687 >\[ = — 0.535 

 The condition ecjualions reduced from these values are: 

 .)•.=— 0.085,r,4-0.396.r,+0.255.c,—0.038.i-,—0.060>c,— 0.103a-, 

 .f,=:-0.239,/.',—0.346.);,4-0.454,t,+0.068,v,+0.083.r,— 0.129a', 

 with the p;eneral correhxtion-eoefticieiits : 



R^ = 0.856 , n, = 0.938 

 Witli respect to a first expectation with the average uncertainty 

 a, and a^ the expectation has been, tlierefore, improved respectively 

 48 and 65 per cent, and the computation with the help of 6 stations 

 affords an improvement with respect to the use of 5 stations with 

 only 5°/,, for the north-component, but with 157o for the east-com- 

 ponent. The probable uncertainty becomes ± 1.24 and ± 1.05 m. p. s. 



TABLE III. 



Direction 

 gradient 



N 



NNE 



NE 



ENE 



E 



ESE 



SE 



SSE 



S 



ssw 

 sw 

 wsw 

 w 



WNW 

 NW 



NNW 



Direction 

 wind 



N 231° E 

 258 

 285 

 309 

 338 

 3 



25 



45 



62 



80 



96 

 114 

 133 

 154 

 178 

 204 



Wind- 

 velocity 



Angle of 

 deviation 



3.43 m.p.s. 



3.39 



3.35 



3.56 



3.76 



4.11 



4.44 



4.96 



5.28 



5.46 



5.39 



5.14 



4.73 



4.27 



3.86 



3.58 



51° 



56 



60 



62 



68 



70 



70 



67 



62 



57 



51 



47 



43 



42 



43 



47 



