290 



Variations of Magnetic Declination. [Jan. 30 r 



other, rather than with minimum points or depressions. Indeed, the 

 researches of Broun and others, from a different point of view, 

 strengthen this conclusion, which is, however, abundantly supported 

 by a glance at the curves themselves ; 



(2.) The oscillations of the Tre van drum curve are greater than 

 those of the Kew curre ; 



(3.) In many cases where there is a want of striking likeness 

 between the oscillations of the two curves, there are yet noticeable 

 traces in the one. curve corresponding to the oscillations of the other. 

 There are, however, a few cases where there is a want of apparent 

 likeness. 



(4.) In general, though not invariably, the oscillations of the 

 Trevandrum curve follow rather than precede the corresponding 

 oscillations -of the Kew curve. This will be perceived from the 

 following numerical estimate : — 



Table I. — Exhibiting the lagging behind of the Trevandrum Curve in 



Point of Time. 



Trevandrum minus 



Oscillations. Kew in clays. 



1858 a +15 



b .... ".. +30 



1859 c +11 



d +32 



e +8 



/ +11 



g -13 



h -30 



1860 i -11 



h - 8 



I +40 



1861 m +19 



n 



1862 o +25 



1863 p +11 



q +21 



r +25 



1864 s -11 



Mean + 97 days. 



We venture to present the evidence in its present form, but forbear r 

 in the meantime, to discuss the subject at greater length. 



