AT SEVERAL PLACES IN THE UNITED STATES. yj 



Magnetic Dip at Twinsburgh, Ohio. Latitude 41° 20' N.; Longitude 81° 26' W. 

 Place of observation a quarter of a mile north of the village. 





Date. 







H( 



jur. 



Needle. 



No 



Readings. 





Dip. 



1840, 



Sept. 



23d, 



4— 



■5, 



P.M. 



No. 1, 





40 



72 



° 54'.8 



(C 













No. 1, poles reversed, 





40 





48.7 



(( 













Mean of No. 1, 





80 





51 .8 



U 













No. 2, 





40 





48.2 



(( 













No. 2, poles reversed, 





40 





53.3 



(C 













Mean of No. 2, 





80 





50.8 



cc 













Mean of both needles, 





160 



72 



51 .3 



Magnetic Lip at Tallmadge, Ohio. Latitude 41° 6' N.; Longitude 81° 26' W. 

 Place of observation half a mile south-west of the village. 





Date. 







Hour. 



Needle. 



No. Readings. 





Dip. 



1840, 



Sept. 



28th, 



8— 



91, 



A.M. 



No. 1, 



40 



72 



" 43. 6 







(i 



•« 







No. 1, poles reversed. 



40 





54.1 







(C 









Mean of No. 1, 



80 





48.9 







(( 









No. 2, 



40 





53.8 







11 









No. 2, poles reversed. 



40 





49.0 







n 









Mean of No. 2, 



80 





51 .4 







(( 









Mean of both needles. 



160 



72 



50.1 



I have always aimed to remove all iron from my person before commencing 

 a series of observations; but after concluding the preceding, I found, to m3rsur- 

 prise, an iron key in my coat pocket. The observations were, therefore, sub- 

 sequently repeated in the same place. 



Magnetic Dip at Shalersville, Ohio. Latitude 41° 15' N.; Longitude 81° 13' W^ 



Place of observation forty rods west of the Presbyterian church. 





Date 





Hour. 



Needle. 



No 



Readings. 





Dip. 



840 



, Oct. 



15th, 



2i— 4, P. M. 



No. 1, 





40 



72 



°59'.l 











No. 1, poles reversed, 





40 





51.9 











Mean of No. 1, 





80 





55.5 











No. 2, 





40 





54.3 











No. 2, poles reversed, 





40 





61.0 











Mean of No. 2, 





80 





57.6 











Mean of both needles, 





160 



72 



56.6 



