BETWEEN SUN-SPOT FREQUENCY AND TERRESTRIAL MAGNETISM. 



179 



D. 



Disturbance limit _ 

 range 



0-41 



H. 



V. 



0-30 



If instead of the ranges from the mean diurnal inequality for the year we had 

 taken the arithmetic mean of the 12 monthly inequality ranges, we should have 

 obtained a somewhat smaller fraction in the case of D. But the figures are at least 

 suggestive that the explanation of the great difference in the number of disturbances 

 in D, H, and V may be largely due to the disturbance limit being less exacting in 

 one element than another. 



TABLE XXL (Units for " Values" 1' in D, ly in H and V.) 

 Aggregate Values and Numbers of Disturbances at Batavia. 



33. On examining Table XXI. it will be seen that the number and aggregate 

 value, though generally increasing or decreasing together, are far from being in a 

 constant ratio in any of the elements. As to which is the better measure of 

 disturbance, opinions may well differ ; but the aggregate values constitute probably 

 the nearest parallel to the Pawlowsk and Katharinenburg data in Tables IX. and XVI. 



According to both numbers and aggregate values, 1893 was less disturbed than 

 1892 or 1894, but its relative quietness is not so conspicuous, especially in D and V, 

 as it was at Pawlowsk or even Katharinenburg. 



Table XXI. must, of course, receive contributions at least, in the case of H 



2 A 2 



