252 Magnetic Influence of Solar Light. 



The needle B. was in every respect the counter-part of 

 A, having been cut from the same piece of steel ; the same 

 stirrup and suspending filament were employed in both 

 series of experiments, and the only difference between them 

 was, that in order to ensure a greater degree of accuracy, a 

 larger number of Oscillations was counted at each observa- 

 tion. The latter series were made under peculiarly favour- 

 able circumstances, the weather being still and clear, and the 

 sun very bright and powerful, both in light and heat. 



TABLE VI. 



Shewing the Duration of Needle C. before exposure. 



Hour of 

 Day. 



bD eg 



u-5 



o 6 

 Q 



O 02 



O .Th 



to 



. 03 



o > 



n 



Remarks. 



Jan. 

 19th 



11 



In. 



5 



In. 

 0.04 



64° 



20 

 20 

 20 

 20 

 20 



Sea. 

 610 

 614 

 616 

 620 

 615 



Sums, 

 Means, 



100 

 1 



3075 



30.75 



TABLE VII. 



Shewing the Duration of Oscillations of Needle C. after exposure. 



No. of 

 Oscill. 



Duration 

 j of Oscill. 



No. of 

 Traverses, 



20 

 20 

 20 

 20 

 20 



Sea. 

 615 

 615 

 615 

 615 

 617 



200 



100 



3077 





1 



30-77 





'Exp., 



Date of 

 | Exp. 



Hour of 

 Day. 



h of 

 idle. 



No. of 



A. M. 



P. M. 



bl) 03 





Jan. 







In. 



1 



19th 



12 





5 



2 











3 











4 











5 











O Qi 



In. 

 0-04 



83° 



Sums, 

 Means, 



Remarks 



