A. D. Bache on the Horizontal Component of Magnetic Force. 269 



, 339<, 36j 494 5i 8o 69 



-. 50H. 186 28«9.857! 242 452 



,^.- I 7^0 2994 421 863 1685714 128 4i 691 721 365i W3J 



^' V. ; 520 1870 35 1955 i85| 73o o| 34| 02,73 ^74o 6763 



|F"eb. 649 20^5 Uo 168°! o| 44 oi Vol I'fi'cS '789' 4747 



'M.ch' 643 .4694.5 76. o| 39 oi4.2 37[ ^90 lof: 477. 



Lii^J 



The average amount of a disturbance increasing the lionzon- 

 tal force is 45 scale divisions or 0-0069 in absolute measure ; the 

 average amount of a disturbance decreasing the same is o4 scale 

 divisions or 00082 in the value of X. The ratio of these num- 

 bers is as 1 : 1-2 whereas at Toronto the ratio is 1 : 6-4. 



The law of the monthly inequality for amount of increasing 

 or decreasing disturbances is, as in the preceding case, very in- 

 distinct and further obscured by the small absolute amount ol 



In the following table, No. XIII, the larger disturbances have 

 been distributed over the different hours of their occurrence ; in 

 this combination the bi-hourly series (of the even hours) of ob- 

 servation has been used throughout. 





















Hour. 



."nedit'r". 





araou..l 



°" 



f^ 



s 



1 



.46 



1 



fi 



10 





53 



r'l 





68j5 



161 



r. 



\<x> 





6634 



i35 



5? 



;:? 





iin 



;?9 



53 



109 



Directing our attention to the columns of aggregate amount 

 and ornui^s of nuX of occurrence, we fi^^ '^f^'P^i^^ 

 -u. about 11 A. M., which -ems to corres^^^^^^^^ 

 Biaxiinum of corresponding ratios at -^oroiito.^'^ J'- 

 tbree hours earlier ; the principal minimum occurs about A. m., 



