AT TWENTY-ONE STATIONS IN EUROPE. 



79 



needles accompanying the dipping circle, No. 2 did not give uniformly as ac- 

 cordant results as No. 1; but, in cases where differences appeared, I endea- 

 'voured, by increasing the number of observations, to reduce the amount of pro- 

 bable error. 



In presenting these results to the society, I have concluded to give the ob- 

 servations at each place, in general, separately, rather than to tabulate, at once, 

 the whole series; this will enable me more readily to make such remarks as 

 may be necessary, and also to compare the results with those of other observers, 

 as far as I am acquainted with them, which will make the paper more com- 

 ])lete than if I had confined it merely to my own conclusions.* 



The observations will be given in the following order : — Those at Dublin, 

 Edinburgh, London, Paris, Brussels, Berlin, Vienna, Trieste, Venice, Rome, 

 Naples, Florence, Milan, Turin, Chamberi, Lyons, Chamouni, the Flegiere, 

 Oeiiera, Brientz, and the Faulhorn. 



DUBLIN. 



The observations at Dublin were made in the Provost's garden. They in- 

 cluded only the horizontal intensity, as I was not at this time provided with a 

 dipping-needle. The horizontal intensity is compared with that at London by 

 observations made in July, 1837. 







Observations for Horizontal Intensity at Dublin. 





Needle. 



Date. 



Temp. 



No. of 

 Oscill'ns. 



Time of 



Ten 

 Osciirns. 



Corrected 

 Time of 



Ten 

 Osciirns. 



Mean. 



Coeffic't 



of 

 Corr'n 



for 



Loss of 



Magn'm. 



Hor. 



Intensity. 



Lond. 1. 



Cylinder. 



Year. 



Month. 



D. 



H. 



M. 



Fah. ° 



Sees. 



Sees. 



Sees. 



1836 



Nov. 



21 



4 



08 



45i 



200 



36.13 



36.157 









ii 



ii 



(( 



(t 



t( 



21 



441 



1 .14 



.168 









a 



it 



i< 



«< 



(1 



39 



4U 



.12 



.149 



36.158 



0.978 



0.935 



Bar. 



1836 



Nov. 



19 



4 



40 



40 



200 



39.77 



39.862 









(( 



(i 



(1 



ii 



a 



54 



391 



150 



.74 



.833 









(( 



(( 



" 



21 



4 



53 



44^ 



t( 



.78 



.851 



39.849 



0.992 



0.938 



* This is easily done through the abstract contained in Major Sabine's interesting report to the 

 British Association, on the variation of the magnetic intensity observed at different points of the 

 earth's surface. From the Seventh Report of the British Association for the Advancement of Sci- 

 envie, London, 1838. I have, however, referred to the originals, whenever they were accessible, 

 in which cases they are quoted in my paper, without other acknowledgment. 



