294 
LITTLEHALES. 
Lat. 8° 57 / N. PANAMA. Long. 79° 2V W. 
Year. 
Magnetic 
declina¬ 
tion. 
Authority. 
Observer. 
Where recorded. 
1775.9 .... 
o 
—7.80 
Encyclopaedia Britannica, 7th edition, 1842. 
1790.8 .... 
—7.80 
Don A. Malaspina 
Berliner Astronomische Jahrbuch, vol. 53, 1828, 
p. 188. 
1802. 
—8.00 
Encyclopaedia Britannica, 7th edition, 1842. 
1822. 
—7.00 
B. Hall... 
Becquerel’s Trait6 du Magnetisme, 1846. 
1837. 
—7.00 
Belcher. 
Phil. Trans. Royal Society, 1875. 
1849. 
—7.01 
Emory. 
Do. 
1858. 
—6.03 
Friesach .. 
Do. 
1866.4.... 
—5.90 
Harkness.. 
Do. 
1883.2 .... 
-5.03 
Lieut. Barnaud, Fr. N. 
Annales Hydrographiques, 2d series, 1884. 
1885. 
—5.25 
Lieut.CommanderW. Welch 
Hydrographic Office Publication, No. 109, Contri¬ 
butions to Terrestrial Magnetism. 
Year. 
Observed. 
Computed. 
O-C. 
-2 
O-C . 
1775.9 .... 
o 
—7.80 
o 
—7.60 
—0.20 
0.0400 
> 
1790.8 .... 
—7.80 
—7.78 
—0.02 
0.0004 
1802........ 
—8.00 
—7.90 
—0.10 
0.0100 
1822. 
—7.00 
—7.52 
+0.52 
0.2704 
1837. 
—7.00 
—6.99 
—0.01 
0.0001 
Probable error of a single observation = +13'. 
1849. 
—7.01 
—6.48 
—0.53 
0.2809 
Period = 200 years. 
1858. 
—6.03 
—6.10 
+0.07 
0.0049 
1866.4 .... 
—5.90 
—5.77 
-0.13 
0.0169 
1883.2 .... 
—5.03 
—5.31 
+0.28 
0.0784 
1885. 
—5.25 
—5.27 
+0.02 
0.0004 
0.7024 
Empirical equation for determining the declination for any year: v = — 6°.540 
4- 1.367 sin 1.8 (t — 1850) -j- 0.105 cos 1.8 (t — 1850). 
