1879.] 



Variations of Magnetic Declination. 



289 



the originals ; but each number in the transformed table being the 

 mean of nine consecutive numbers in the original table. Curves were 

 then plotted from these transformed tables. In the diagrams attached 

 to this paper, these equalized curves are compared together for 

 the two observatories, figs. 1 and 3 giving the Kew curves, and 

 figs. 2 and 4 those for Trevandrum. Points in the two curves, which 

 are supposed to correspond, are represented by similar letters of the 

 alphabet. 



A comparison of these curves appears to lead to the following con- 

 clusions : — 



(1.) Generally speaking, maximum points or risings in the one 

 curve must be associated with maximum points or risings in the 



