452 RECTIFICATIONS AND ADDITIONS. 



same result was found for the sun's action, they also both 

 agreed in yielding assured evidence " that the lunar-diur- 

 nal variation corresponding to different years shows no 

 conformity to the decennial inequality manifested in 

 those of the solar-diurnal variation." No sufficient ex- 

 planation seems yet to have been given of the lunar- 

 diurnal magnetic variation, as General Sabine has also 

 remarked that "the earth's inductive action reflected 

 from the moon would seem to be too feeble to account 

 for it." (Sabine in the Phil. Trans, for 1857, art. i. p. 7 ; 

 and in the Proceedings of the Koyal Society, vol. viii. 

 No. 20, p. 404.) As the magnetic portion of this volume 

 was printed almost three years ago, it appeared to be 

 particularly needful, in regard to a subject to which I 

 have been so long attached, to complete it, in some 

 measure, by some subsequent additions. 



