308 Variation and Dip of the Magnetic Needle. 
Table exhibiting the Dip of the Magnetic Needle in different parts of the United 
States. , 
P Lat. N. Lon. W.) Dip. { Date. Authority. 
wadeatnovenres. (© ~ 3°" 1° ” 
\Cambridge, 42 2271 769 51|1780 ic ajcioogpensne 
oo oe 6e | [7 ee td 69 4] 1782 
ee se 66 | 6% 6K IGOQ 4AIILTS 3 
vie So 42 672 36,74 11/1834 Prof Babe 
HODE ISLAND. | 
iPcbintahed, 41 4971 25'74 3/1834) “ “ 
NEW YORK. | 
Albany, 42 3973 45,74 51/1833'Profs. Henry and Cram. 
i 6 66 | ee 666 174 40/1834|Prof. Bache. 
West Point, 41 2374 1/73 26)1833/Courtenay and Henry. 
6s ce ce | oe wt 73 37 1834 Pr f 
New York City, 40 4374 173 5/1822\C 
Hes eo te) ee 6 TB 27) 1825/Sir fobs Franklin, 
' t. Back. 
6 Tet tel ce se 72 49)1834 Cap 
2g se | ee 66 72 5Q1834P rof. Bache. 
PENNSYLVANIA. 
Philadelphia, 39 57/75 1272 0)1834 Bache and Courtenay. 
Pittsburgh, 40 3280 278 12/1819 Long’s Expedition. 
MARYLAND. | 
pera 39 17,76 li 59/1834 Prof. Courtenay. 
iharlotteanilin 38 278 an 9\1834 Prof. Patterson. 
OHIO. 
Urbana 40 383 4271 3911838 Prof. Locke. 
Pree 39 5583 371 51838 “6 
Springfield, 39 5383 4771 29/1 S 
Dayton, 9 4584 971 23/1838 “ 
Cincinnati, 39 684 27,70 46,1838 ba 
KENTUCKY. 
Shippingport, 38. 1585 3070 151819|Long’s Expedition. 
MISSOURI, | 
Eng. Cantonment, 41 2595 4471 7/1820) « * 
Cow Island, 39 2594 069 5OISI9) « = 
Charaton, 39 1092 2069 501519) 7 
Fort Osage, 39 1094 1869 IS/ISI9) * 5 
Frankl 38 5792 5769 30,1819) “ ps 
St. Charles, 38 4689 4870 5SIISI9) * = 
Belle Fontaine, 38 4389 36;70 QISI9) = 
St. Louis 38 3689 36/70 30/1819} « 7 
Cote sans ‘Dessein, 38 36,91 5670 50/1819)“ Se 
Merrimack river, 38 26,89 36:70 O/I8I9) = 
From the preceding observations it seems impossible satisfac- 
ard to determine what changes the dip of the needle has ex- 
enced in this country. Bron the course of the observations 
Prof. Bache, it may be inferred that the 
