42 



O. A. Åkesson 



D The Motions in Longitude of Spots of different Sizes. 



As previously stated, the dispersion of the motions decreases with increasing 

 spot-area. Thus, if it should prove that the mean of the motions in longitude 

 remains constant for spots of different sizes, it follows from (20) that the angular 

 velocity will be greater, if determined from larger spots. 



This question we shall now proceed to investigate. As a basis for this inquiry 

 we use the values in table XVI. In this table the meaias and dispersions of the 



motions in longitude 



TABLE XVII. 

 The Values of for different Spot-sizes. 



> -1909. 





1.00 



1.40 



1.80 



2.20 



2,60 



;}.oo 



iYi and Si 



+0.879 



+ 1.097 



+ 1,345 



+0.998 



+i',:î45 



+0.997 



N„ » S, 



-1-1.163 



+0.974 



+0.932 



+0.866 



+ 1.064 



+0.948 



» ^3 



+0,4,55 



+ 1.010 



+0 775 



+0.648 



+ 0.64 i 



+0.723 



iV, . 



+0.448 



+0.429 



+0.767 



+0.558 



+0.565 



+0.494 





+0,225 



+0.440 



+0.262 



+0.182 



+0.341 



+0.435 





— 0.755 



+0.143 



+0.284 



+0.004 



+0.267 



+0.530 



The Values of 



TABLE XVIII. 

 . for different Spot-sizes. 



as well as in latitude 

 for different spot- 

 areas are given. Al- 

 though the motions 

 in latitude are also 

 introduced in the 

 table, we shall not 

 discuss them in this 

 connection. 



In making this 

 table, the material 

 of observation has 

 been divided accord- 

 ing to log A (= (o) 

 in classes with a 



class-interval of 

 0.400. The spots for 

 which (Ü is < 0.800 

 or > 3.200 being 

 few, these groups 

 have not been noted 

 in the table. The 

 observations within 



each sucli group have subsequently been divided into latitude-zones, after which the 

 means and dispersions of the motions within each zone have been computed. 

 As the angular velocity V is determined from the formula 



V = ,35'.4Gl + sec ß — 0.0282a/ sec^ß , 



we have in the first place to exauiine whether the quantity 



sec ß — 0.0282a.,.^ sec^ß 



varies with co within each zone. 





1,03 



1,40 



1,80 



2.20 



2.60 



3.00 



N, and S, 



2.604 



2.750 



2'.591 



1.730 



1.731 



1.421 





2.998 



3.032 



2,431 



1.823 



1.665 



1.549 





3.207 



2.997 



2.426 





1.713 



1.632 



N, » S, 



2.871 



2.950 



2.621 



2.052 



1.768 



1.925 



« s. 



2 978 



3 017 



2.674 



2.126 



1.830 



1.744 



' S, 



2.S.21 



3.017 



2.444 



1.910 



1.487 



2.050 



