AT TWENTY-ONE STATIONS IN EUROPE. 



83 



Observations for Horizontal Intensity at London and Paris, continued. 



Place. 



Needle. 







Date. 



Temp. 



No. of 

 OsciU'ns. 



Time of 



Ten 

 Osciirns. 



Corrected 

 Time of 



Ten 

 OsciU'ns. 



Mean. 



Coeffic't 



of 



Corr'n 



for 



Loss of 



Magn'm. 



Horizontal 

 Intensity. 







Year. 



Month. 



D. 



H. 



M. 



Fah. » 





Sees. 



Sees. 



Sees. 



Paris 1. 



Lond. 1. 



Paris 



Cylinder. 



1838 



July 



4 



1 



07, P. M. 



73^ 



350 



34.956 



35.076 













4( 



(( 



11 



11 



1 



36, 



tt 



326 



.944 



.066 













11 



&( 



11 



17 



12 



04, 



72 



350 



.903 



.026 













It 



(( 



11 



11 



it 



35, 



73 



11 



.850 



34.971 













11 



ii 



11 



If 



1 



03, 



74 



11 



.934 



35.053 













11 



(C 



11 



11 



2 



06, 



821 



It 



.934 



.038 













11 



'• 



If 



11 



ft 



29, 



83§ 



If 



.931 



.035 



35.038 





1.000 



0.938 



Bar. 



" 



11 



4 



3 



34, 



73i 



356 



37.714 



37.812 













(( 



i( 



It 



11 



.1 



56, 



72i 



i( 



.703 



.805 













It 



(( 



11 



17 



11 



16, 



84i 



300 



.763 



.811 













tt 



(( 



11 



11 



11 



36, 



85;^ 



(4 



.792 



.836 



37.816 





1.000 



0.936 



London 



Cylinder. 



(i 



Aug. 



15 



1 



03, 



65 



350 



36.232 



36.271 













11 



(t 



It 



11 



(( 



25, 



11 



a 



.239 



.278 



36.274 



.9962 



1.066 



1.000 





Bar. 



(( 



11 



11 



2 



23. 



11 



350 



39.032 



39.064 













(t 



(( 



11 



41 



(( 



49, 



11 



tt 



.030 



.062 



39.063 



.9982 



1.068 



1.000 



The final mean of these results gives the horizontal intensity at Paris 1.066, 

 that at London being 1.000. By a series of observations with six needles, in 

 1827, Major Sabine found the same element to be 1.071: the highest result 

 which any one of his needles gave was 1.073, and the lowest 1.0675. 



The following observations of the dip were made at the same places with the 

 foregoing. At Paris, in 1837, the observations with needle No. 2 were made 

 at such a late hour as to be unsatisfactory, from a deficiency of light; I have, 

 therefore substituted for them the dip given by the two needles used in the 

 Statical method, and corrected by a comparison of their results at London with 

 those of the other two needles, the poles of which were reversed. Needle No. 

 2 was in the hands of Mr. Robinson, for alteration, in 1838, and I have again 

 used the corrected results given by the statical needles. The total intensities 

 aye calculated from the mean horizontal intensity and the observed dips. 



