Variation and Dip of the Magnetic Needle: 305 
Place. Lat. N. jLon. Wj Variation. | Date. Authority. 
KENTUCKY, Cee = Bee Sa 
Augusta, 38 50/33 50) 5 0 x./1805 Public Surveys. 
OHIO. 
Rapids of Maumee, [41 30/83 30) 248 [1810 Jared ee 
Hudson, 41 13)81 30) 1 14 |1837,Prof. Loo 
Defiance, 41 15/84 23) 4 30 1810 Jared Mansfeld 
Poland, 41 0Oj80 37) 1 21 “ 
Canfield, 41 0/80 50} 1 37 + sé “ 
Berlin, 41 O81 3 1 48 “ “6 “ 
Atwater, {41 O31 21,2 4 ss nad bad 
Suffield, 41 OjS1, 34) 2 22 oo s6 6 
Coventry, 41 O/s1 48,219 | « | «“ 
Norton, 41 Q/S1 53] 2 30 “ “ “ 
Seneca, 41 O83 20) 3 57 ss 6s + 
\Chippeway, 40 55/351 48) 2 36 ” * a 
marietta, 39 25/81 26) 2 36 st = 
co ee ee) FeO «SSS Prof. Loomis. 
Mouth of Miami river,39 884 45) 5 10 1810 Jared Mansfield. 
Cincinnati, 39. 784 27| 5..0 ” a 
Portsmouth, 38 4882 50,5 O 1905,P ublic Surveys. 
INDIAN 
Madison, 38 45/85 15} 5 25 nt pe ae 
South Hanover, 38 45'85 23) 4 35 
nnes, 38 42:87 20| 6 45 1510 Jared Mansiield 
Falls of the Ohio, 38 20/85 40) 5 50 | 
On the Ohio river, 38 10:86 30) 6 30 cot thle. sas 
Mouth of the Wabash,38 05S 0) 7 10 “ “ “6 
ILLINOIS. 
Chicago, 42 O87 40| 6 12 |1823 Long’s Expedition. 
Jacksonville, 39 4590 18) 8 45 [1833 Prof. Sturtevant. 
Iton,- 38 5290 12} 8 0 |1835Mr. Loomis. 
Cahokia, 38 “ig sp 9 8 25 |1810 Jared Mansfield. 
Kaskas} 37 57/89 55| 7 20 1809 Public Surveys. 
Mouth of Ohio river, 37 489 ©! 7 20 |1809\Jared Mansfield. 
MISSOURI 
Franklin, 38 5792 57\11 42 |1819 Long’s Expedition. 
St. Louis, 38 3689 36/10 47 a + és 
“ so se) ce 66) 8 49 = |1835.Col. Nicolls. 
MICHIGAN. 
Detroit, 42 3082 58 248 (1810 Jared Mansfield. 
MISSOURI & WISC. TERS 
Lake of the Woods, 49 094 O11 1  |1823Long’s Ex. St. Peter’s. 
samp Monro 48 59 13 17 re og 
Island in Rainy Lake, |48 35:92 30, 8 15 ve Bg <7 
N. coast of L. Superior 47 5890 0 6 21 “ “ “ 
Fort of Colum. Fir Co.|45 39:96 3412 29 e * = 
Mouth of St. Peter’s R..44 5393 810 29 | « 8 = 
Encamp. on St. Peter’s\44 4197 012 21 = + “i 
Fort Crawford, 43 lee 52 : 49 <a * - 
Engineer Cantonment, 41 2595 4412 59 |1819 Long's Exp. Rocky Mts. 
Cow Island, 39291 Ollg2 | «lee 
Vou. XXXIV.—No. 2. 39 
