61° 80° 
eons | 
ISO-MAGNETIC LINES =~ 
OF PENNSYLVANIA “=~ 
bel FOR i849. 
BY A.D. BACHE, SUPDT. 
U.S.CDAST SURVEY 
en. 
Se ee 
oe OR 
ASHTABULA Lé 
2 r 
s ea 
sty he 
os et 
fee 
b Bee. ae = 
tf ee 
elie 
J} * Ny We : i ‘S } 
FCONOM fae : 
ae is silty Ad 7. 2 
4 Mee aa 
N 
v j 
G ih 
9 
See tee oe nll 
er 
MAGNETIC STATIONS 
DECLINATION i842 
-------- DECLINATION 1862 
—— INCLINATION 
HORIZONTAL FORCE 
-------- TOTAL FORCE 
Ppeniaalise! 2 “% 
74° eee 
{39 
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i} 
1 
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