( 305 ) 

 GRONINGEN 1891—1905 (b). 



Year 



June 



Julv 



Aug. 



Sept. 



It was to Ite expected that in these tables more cases would he 

 found where the signs do not agree, or the magnitude of the devia- 

 tion in one series of numbers is not proportional to that in the 

 other series: indeed, all disturbing causes exert their full influence 

 here. If however we leave out of consideration those cases where 

 one of the deviations is zero, and those where the deviation of the 

 number of summerdavs is but one, or the deviation of the mean 

 temperature not more than 0.°2 (Groningen 6) then we obtain the 

 following résumé : 



Signs equal. 

 Number of Sums 



cases 



T S 



114 927 



3 J 



50 



31 



186 



1275 



Groningen 



Utrecht 



Groningen h 



Signs opposite. 

 Number of Sums 



13 



3b,4 836 



19 



17 



20 



Proceedings Royal Acad. Amsterdam. Vol. X. 



