AT VARIOUS PLACES IN OHIO AND MICHIGAN. 5 



Magnetic Dip at Ann Arbor, Michigan. Latitude 42° 18' N.; Longitude 83° 45' W. 

 The place of observation was an open field, a few rods west of the village. 



Date. Hour. Needle. No. Readings. Observed Dip. 



1839, May 14, 4— 6, P. M. No. 1 80 73° G'-5 



" " " " 2 80 21 -2 



Mean of 160 observations wiih two needles, 73 13 -9 



Magnetic Dip at Ypsilanti, Michigan. Latitude 42° 14' N.; Longitude 83° 38' W. 



The place of observation was a hill on the east side of Huron river, a few 

 rods from the village. 



Date. Hour. Needle. No. Readings. Observed Dip. 

 1839, May 15, 12— 2, P. M. No. 1 80 73° ll'-9 



" " " 2 80 24-1 



Mean of 160 observations with two needles, 73 18 -0 



Magnetic Dip at Monroe, Mchigan. Latitude 41° 55' N.; Longitude 83° 28' W. 

 Place of observation an open field, a few rods south-east of the village. 



Date. Hour. Needle. No. Readings. Observed Dip. 



1839, May 16, 4—6, P. M. No. 1 80 73° 24'-l 



" " «' " 2 80 40 -6 



Mean of 160 observations with two needles, 73 32 '3 



Magnetic Dip at Toledo, Ohio. Latitude 41° 41' N.; Longitude 83° 33' fV. 

 Place of observation an open field, a few rods west of the village. 



Date. Hour. Needle. No. Readings. Observed Dip. 



1839, May 17, 5— 7, P. M. No. 1 80 73° l'-2 



" " " 2 80 10 -9 



Mean of 160 observations with two needles, 73 6-1 



Magnetic Dip at Maitmee City, Ohio. Latitude 41° 34' N.; Longitude 83° 38' Tf'. 

 Place of observation an open field, a few rods north of the village- 

 Date. Hour. Needle. No. Readings. Observed Dip. 

 1839, May 18, 5—7, P. M. No. 1 80 72° 50'-8 



" " " " 2 80 47 -4 



Mean of 160 observations with two needles, , 72 49 • I 



VII. B 



