402 DR. C. CHREE: ANALYSIS OF RESULTS FROM THE FALMOUTH MAGNETO- 

 TABLE XIX. Annual Variation (1891 to 1902). Date of Occurrence of 



First Maximum. 



The figures in small print denote the differences in days between the times of 

 occurrence of corresponding maxima at Falmouth and Kew, the plus sign indicating a 

 later occurrence at Falmouth. The phase angles, though recorded in Table XVIII. 

 and in Table XXX. of (A) only to the nearest whole degree, were really worked out 

 to minutes of arc, and the differences in Table XIX. were derived from these more 

 complete angles. The differences are also nearly free from several sources of 

 uncertainty which enter nearly equally into the absolute values of the phase angles 

 at Kew and Falmouth. 



The algebraic mean of the differences, when taken to the nearest 1' and converted 

 into time, represents + 22 hours, but if the somewhat outstanding result from the 

 annual term for c 4 in D be omitted, this becomes 1 hour. Thus no certain con- 

 clusions can be drawn as to whether the maxima in the annual variation appear 

 earlier at Kew or at Falmouth. The truly remarkable approach to coincidence 

 between the Kew and Falmouth dates certainly points to the conclusion that the 

 annual and semi-annual terms represent very real phenomena, determined by laws 

 which vary but slightly over large areas. 



These results, it must again be pointed out, relate to the mean year of a sun-spot 

 cycle, and so throw no light on the differences that may exist between individual 

 years' results at the same or at different British stations. 



Relations with Meteorological Ptienomena. 



17. Table XX. gives the mean values of certain meteorological elements at 

 Falmouth for the entire period 1891 to 1902, the sun-spot maximum period 1892 to 

 1895, and the sun-spot minimum period 1899 to 1902. It also gives the algebraic 

 excess of the mean for the sun-spot minimum period over that for the sun-spot 

 maximum period. Corresponding excess data for Kew are given (a) for the same 

 periods as at Falmouth, (b) when the sun-spot minimum period consists of the three 



