304 
LITTLEHALES. 
Lat. 33° 02' S. 
VALPARAISO. 
Long. 71° 39' W. 
Year. 
Magnetic 
declina¬ 
tion. 
Authority. 
Observer. 
Where recorded. 
1709.. 
1744.. 
1793.. 
1802.. 
1821.. 
1823.. 
1825.. 
1831.. 
1835.. 
1837.. 
1838.. 
1859.. 
1860.. 
1882.6 
1883.2 
1884.... 
—9.50 
-12.50 
-14.82 
-14.92 
-14.72 
-15.68 
-15.87 
-15.00 
-15.30 
-15.58 
-15.60 
-15.67 
-15.85 
-15.43 
-15.25 
-15.68 
Feuillee. 
B. Hall. 
Morrell.. 
Beechey . 
King.. 
Laplace. 
Beechey.. 
La Venus .. 
Novara Expedition 
Harkness. 
Lieuts. Barnardibres and 
Barnaud, Fr. N. 
.do.... 
Lieut. J. W. Carlin, U. S. N. 
Phil. Trans. Royal Society, 1877. 
Voyage of the Adventure and Beagle. London, 
1839. 
Do. 
Becquerel’s Traite du Magnetisme. 
Do. 
Phil. Trans. Royal Society, 1877. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Smithsonian Contributions to Knowledge, No. 
239, 1873. 
French Magnetic Survey. 
Annales Hydrographiques, 1884. 
Hydrographic Office Publication, No. 109. 
Year. 
Observed. 
Computed, 
O-C. 
0-0 . 
1709. 
1744. 
1793. 
1802. 
1821. 
1823. 
1825. 
1831. 
1835. 
1837 . 
1838 . 
1859. 
1866. 
1882.6 ... 
1883.2 ... 
1884. 
- 9.50 
-12.50 
-14.82 
-14.92 
-14.72 
-15.68 
-15.87 
-15.00 
-15.30 
-15.58 
-15.60 
-15.67 
-15.85 
-15.43 
-15.25 
-15.68 
-10.24 
-11.98 
-14.38 
-14.76 
-15.39 
-15.44 
-15.49 
-15.61 
-15.67 
-15.69 
-15.69 
-15.72 
-15.68 
-15.24 
-15.23 
-15.21 
+0.74 
—0.52 
—0.44 
—0-16 
+0.67 
—0.24 
—0.38 
+0.61 
+0.37 
+ 0.11 
+0.09 
+0.05 
— 0.22 
—0.19 
— 0.02 
—0.47 
0.5476 
0.2704 
0.1936 
0.0256 
0.4489 
0.0576 
0.1444 
0.3721 
0.1369 
0.0121 
0.0081 
0.0025 
0.0484 
0.0361 
0.0004 
0.2209 
Probable error of a single observation = ± 18 
Period = 360 years. 
2.5256 
Empirical equation for determining the declination for any year: v = — 12°. 639 
+ 0.047 sin (t — 1850) — 3.124 cos (t — 1850). 
