814 
MAGNETIC SURVEY IN NORTH AMERICA 
The total force at Cincinnati, the base station of Dr. Locke’s survey, has therefore 
been taken =1*795 ; and the final column in the following - Table has been computed 
accordingly ; employing for that purpose the Inclinations observed at the same 
stations by Dr. Locke, contained in § 12, where also the geographical positions of 
the stations are given. 
Table XLVI. — Values of the Magnetic Force at the stations of Dr. Locke’s survey. 
Station. 
Date. 
Ratios of 
the hori- 
zontal force 
to unity at 
Cincinnati. 
Ratios of the total force. 
Station. 
Date. 
Ratio of 
the hori- 
zontal force 
to unity at 
Cincinnati. 
Ratios of the total force. 
To unity at 
Cincinnati. 
To 1*836 at 
Toronto. 
To unity at 
Cincinnati. 
To 1-836 at 
Toronto. 
Cincinnati 
Dayton 
Dayton 
Springfield 
Urbana 
Columbus 
Columbus 
St. Louis 
Davenport 
Lostgrove 
Wabisepinnecon River ... 
Iron Ore Bed 
Brown’s Settlement 
Mahoqueta River 
Farmer’s Creek 
White Water River 
Mahoqueta River * 
Dubugues Town 
Little Mahoqueta 
Turkey River 
Prairie du Chien 
Blue Mound 
Madison 
Mineral Point 
Hamilton 
Piqua 
Lebanon 
Mason 
Williamstown 
Lexington 
Clay’s Ferry 
Frankfort 
Louisville 
Mount Vernon 
New Flarmony 
Princeton 
Vincennes 
Paoli 
Philadelphia 
Philadelphia 
Philadelphia 
Pittsburg 
Pittsburg 
Pittsburg 
Chambersburgh 
Mount St. Mary’s 
Baltimore 
Baltimore f 
Trenton 
Newark 
Newark 
New Yorkf 
New Yorkf 
New York§ 
New York§ 
New York 1| 
Newhaven 
1838. 
1840. 
1838. 
1838. 
1838. 
1845. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1839. 
1840. 
1840. 
1840. 
1840. 
1840. 
1840. 
1840. 
1840. 
1840. 
1840. 
1840. 
1840. 
1840. 
1840. 
1841. 
1842. 
1844. 
1841. 
1842. 
1845. 
1842. 
1842. 
1841. 
1841. 
1841. 
1841. 
1844. 
1841. 
1844. 
1841. 
1844. 
1841. 
1842. 
1-0000 
•9582 
•9544 
•9494 
•9533 
•9666 
•9644 
1-0430 
•9385 
•9360 
•9302 
•9085 
•9181 
•9034 
•9144 
•8927 
•8897 
■8805 
•8813 
•8732 
•8763 
•8540 
•8521 
•8686 
•9383 
•9461 
•9720 
•9770 
10122 
10120 
1 0203 
1 0151 
1 0234 
1-0646 
1 0581 
1 0447 
1 0260 
10313 
•9174 
•9178 
•9151 
•8915 
•8907 
•8869 
•9216 
•9319 
■9370 
•9319 
■9246 
■8785 
•8756 
■8835 
•8817 
•8828 
•8811 
•9003 
•8385 
1-0000 
1-0032 
•9991 
•9978 
10122 
•9967 
•9957 
•9973 
1-0120 
1 0154 
1 0206 
1 0302 
10129 
1-0178 
1 0228 
10165 
1 0093 
1-0130 
10160 
1-0091 
10187 
1-0174 
1-0378 
10137 
10035 
10026 
10011 
•9989 
•9932 
•9854 
•9893 
•9887 
■9965 
•9913 
•9908 
•9923 
■9985 
•9880 
•9943 
•9955 
■9918 
1 0052 
1 0041 
1 0034 
•9964 
•9977 
•9935 
•9914 
•9978 
•9957 
•9925 
•9943 
•9944 
•9918 
•9924 
•9942 
•9884 
1-795 
1 1-797 
J 1-791 
1-816 
1 1-788 
1-790 
1-816 
1-822 
1-832 
1-849 
1 818 
1-818 
1 -836 
1-824 
1-811 
1-818 
1-823 
1-811 
1-828 
1-826 
1-862 
1-819 
1-801 
1-799 
1-797 
1-793 
1-783 
1-769 
1775 
1-774 
1-788 
1-779 
1-778 
1-781 
1-792 
1-775 
j 1-784 
1 1-803 
1-788 
1-790 
1-784 
1-779 
1-790 
1 1-784 
1 1-785 
} 1-781 
J 1-784 
1-774 
Boston 
Cambridge 
Cambridge If 
Bristol 
Huron 
Detroit 
Ann Arbor 
Machinae 
Sault St. Mary 
Encampment 
Houghton’s River 
Magnetic Inlet 
Isthmus 
United States Agency ... 
Eagle River 
Lapointe 
Ontanogon River 
Isle Royale 
Cleveland 
Wheeling 
Wheeling 
Cumberland 
Washingtonff 
Washington ff 
Georgetown 
Mount Vernon 
Princeton 
Princeton §§ 
Princeton || [| 
New Brunswick 
Powkeepsie 
Opposite Powkeepsie 
Greenbush 
Albany 
Utica 
Rochester 
Lockport 
Butfaloe 
Ashtabula 
Warren 
Wells ville 
Toronto ^f^f 
Near Toronto*** 
Marietta 
Near Marietta 
Allegheny Summit 
Portland 
Locke’s Mills 
Bethel 
Goreham 
Mount Washington 
Near Mount Washington. . 
Oxford 
Richmond 
[ St. Mary’s 
Carrolton 
1842. 
1842. 
1845. 
1842. 
1843. 
1843. 
1843. 
1843. 
1843. 
1843. 
1843. 
1843. 
1843. 
1843. 
1843. 
1843. 
1843. 
1843. 
18J3. 
1844. 
4845. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1844. 
1845. 
1845. 
1845. 
1845. 
1845. 
1845. 
1845. 
1845. 
1845. 
1845. 
1845. 
1845. 
1845. 
•8057 
•8040 
•7955 
•8885 
•8834 
•8552 
•8771 
•7159 
•6695 
•6959 
•6713 
•6199 
•6298 
•7171 
•6482 
•7047 
•6862 
•6464 
•8802 
•9167 
•9182 
•9390 
•9414 
•9483 
•9413 
•9685 
•8833 
•8815 
•8905 
•8814 
•8808 
•8197 
•7867 
•7876 
•7876 
•7948 
•7913 
•8054 
•8600 
•8806 
•8927 
•7784 
•7789 
•9566 
•9507 
•9026 
•7535 
•7265 
•7274 
•7442 
•7287 
•7334 
■9732 
•9574 
•9255 
•9662 
•9845 
•9917 
•9860 
•9850 
10123 
10111 
1-0184 
1-0387 
1-0366 
10341 
1-0266 
1-0652 
1-0555 
1-0866 
1-0367 
1-0445 
1-0393 
1 0526 
10163 
1-0129 
1-0070 
•9967 
1-0026 
•9879 
•9849 
•9933 
•9940 
•9927 
•9973 
•9946 
•9959 
1-0094 
•9978 
•9985 
1-0078 
1-0061 
1-0073 
1-0170 
1-0335 
1-0056 
•9999 
1-0229 
1-0220 
1-0025 
■9999 
1-0025 
•9897 
•9950 
•9965 
•9993 
•9915 
•9914 
1-0056 
1-0020 
1-0056 
1-0024 
1-767 
} 1-774 
J 1-768 
1-817 
1-815 
1-828 
1-864 
1-861 
1-856 
1-842 
1-910** 
1-895** 
1-950** 
1-861 
1-875 
1-865 
1-889 
1-824 
j 1-813 
J 1-789 
1-800 
1-773 
1-768 
1-782 
1-783 
1-781 
1-790 
1-785 
1-787 
1-811 
1-791 
1-792 
1-809 
1-806 
1-808 
1-825 
1-855 
1-805 
1-794 
1-836 
1-835 
1-800 
1-795 
1 800 
1-776 
1-786 
1-789 
1-794 
1-780 
1-780 
1-805 
1-799 
1-805 
1-800 
* North Branch. + St. Mary’s College. J Columbia College. 
§ Lunatic Asylum, Manhattan ville. || New Asylum. Mr. Bond’s Magnetic Observatory. 
** At these four stations, which are all within one mile of each other, considerable local disturbance ob- 
viously exists. ff Magnetic Observatory. Grounds of the Capitol, mean of the east and west sides. I 
{>§ Pott’s Wood. mi Rock Hills (trap). Magnetic Observatory. *** In the woods. 
