AT TWENTY-ONE STATIONS IN EUROPE. 



97 



successfully undertaken the solution. The dip given by Professor Forbes, at 

 Chamouni, is 65° 00', and at the Jardin, 64° 58', both differing considerably 

 from my results. 



GENEVA. 



These observations were made in the garden of M. Prevost-Martin, not 

 far from the city ; those with the cylindrical needle on the 24th of August and 

 1st of September, those with the bar on the first occasion; the dip was mea- 

 sured on the second. The observations at Chamouni intervened between the 

 two sets at Geneva. The loss of the chronometer was ascertained from the 

 standard near the Church of St. Peter, which is rated for the use of the watch- 

 makers. 



The numbers for Paris used in the reductions were obtained as stated under 

 the head of Chamouni. 



Ohservations at Geneva. 



For Horizontal Intensity. 



Place. 



Needle. 



Date. 



Temp. 



m 



>a 

 *S 



m 

 o 

 d 

 S5 



m 



o 



Time of 



Ten 



Oscill'ns 



at 60". 



Coeffic't 



of 

 Corr'n 



for 



Loss of 



Magn'm. 



Horizontal 

 Intensity. 



Year. 



Month. 



D. 



H. 



Fail. " 



Sees. 



Paris 1. 



Geneva 



Cylinder 

 Bar 



1837 



(( 



Aug. 

 Sept. 

 Aug. 



24 



1 



24 



1,P.M. 



1*, " 



81.2 

 68.5 

 82.0 



2 

 1 

 2 



662 

 300 

 650 



32.904 

 33.033 

 36.048 



1.0023 

 1.0032 

 1.0008 



Mean, 



1.088 

 1.081 

 1.086 



1.086 



For Dip. 









Geneva, 1837, Sept, 1, Needle No. 1, 64° 52'.4 



No. 2, 47 .3, 





Mean, 64° 49'. 8. 





Total Intensity at Geneva, compared with P 



aris as 



unity, 0,984. 





The horizontal intensity at Geneva, compared with that at Paris, is stated 

 by M. Quetelet* to be 1.0805, and by Professor FoRBEsf, 1.071; my own re- 

 sult agrees best with the former. Professor Forbes determined the dip, in 

 August, 1832, to be 65° 05', and states that it was found, in 1825, by M. Arago, 



* Annuaire de I'Observatoire de Bruxelles, &c,, 1834. 

 t Edinburgh Transactions, vol. xiv. 

 VII. — z 



