32 ©. A. Schott—Magnetic Declination in the United States. 
The third table shows the number of observations at each 
place; the apparent probable error of one observation (includ- 
ing errors arising from want of identity of stations and from 
instrumental defects) expressed in minutes of are; the com- 
puted epoclis of greatest easterly deflection in the secular mo- 
tion, together with the amount and direction of the declination 
at that epoch, and the computed annual changes at the epochs 
1870 and 1880, expressed in minutes 
TABLE III, 
a ne 8 
a alee 4 a 
ss 83|S2e8 mo 
ne Bene ses Pra ses Annual change 
lees ae | 2256|S2e2¢| S86 | wwano..| insem 
2 on” | OS n 1870. . 
se |@882|bsees| S28 
7 ° rd 
Halifax, Ss. 9 +33.) 1711 |+11°5 +16 +0°9 
Quebec, Canada. 10 15 | 1769 + 8°8 +17 pes 
No Factory, Hudson Bay. 5 eS ge ee ee2 ee pepe 
Portland, M 10 9. |" 1164 + 8-0 +24 +16 
batuete ¥t 12 6 | 1810 +774 +5°7 +6°0 
Rutland, Vt. 5 15 | 1807 | +61 | +59°| +54 
Portsmouth, N. H. 4 5 | 1780 UT +31 +2°5 
bight rvport Mass. 4 13 | 1776 +70 +2:9 
5 26 | 1796 | +62 | +5°9(?)} +5°0(2) 
a ak 11 26 | 117% +66 +33 
ambridge, Mass. 23 dl: 1) 1783 +69 +2°9 +2°1 
Nantucket, Mass. G) 173 +6°5 +2°6 +2°3 ‘ 
Providence, R. I 30(?) 7 | 1780 +61 +3°8 i 
Hartford, Con 14 | 179! +5:2 +3°4 +3°0 : 
New Haven, Conn. 14 9} 1801 +4°7 +46 | +43 
Albany, N. Y 12 6 | 1794 +5°2 +4°3 +3°8 5 
Oxford, N 13 EVO girs +3°0 +4°5 +43 
Buffalo, N. Y 7 8 | 1802 00 | +49 | 447 | 
irie, Pa. 4 -- | 1793 | —O-7 | +28 | +2°% 
Cleveland, 0. 11 12 | 1781 —22 +2°3 +1°9 
Detroit, Mich 9 aT | Teel 4 +3°4 +3°0 : 
New York City. 15 Pia +4°0 +2°4 
18(2)} 6 | 1797 | +18 | +46 | +450) © 
Philadelphia, Pa. 14 20| 1807 | +21 | +47 37 
Washing D. C. pas) 6 | 1786 —d0°1 +2°4 +19 
Va. 5 14} 1815 0-0 | +4-8(2)) +4°7(?) 
Charleston, 8. C. 9 19 | 1784. | —6°1 27 +1°8 
. Ga. 15} 1809 | —49 | +3°6 +3°5 
Key West, Fla. 10 4 | 1797 a, +36 | +34 
Havana, Cuba. 6 26 | 1810 —63 +19 as 
Kingston, Jamaica it 25 u 66 +1°9 a 
New Orleans. La, 9 30 | 1831 | —82 | +30 | +34 
Vera Cruz, Mex 7 17 | 1823 —I97 +53 ae 
Mexico, a 9 5 | 1838 —8°9 +3°8 
Acapulco 6 21 | 1837 89 | +31 | +38 
Panama, ee Granada. 7 13 | 178% | —79 | +19 | +1°8 ' 
an Blas, Mex. 5 10 | 1848 | —9°0 +1°3 ve 3 
San Diego, 6 6 | 1925 142 | —1°9 17 
a went 8 21 | 1903 |—164 | —20 | —1'5 : 
San Fra 12 9 | 1893 |—16 1:3 | —0°7 4 
wane Disapolimens, Wikio h 12 | 1932 |—232-6(2?)) —3:4 | —3'l . 
Sitk aska. 10 18) 1855 |— +18 +2°9 q 
U: ka Island, Alaska. 8 17] 18 20-2 +3°4 +44 j 
