or 
5S 
cs 
GENERAL REMARKS. 
1. Variation. 
Captain Fitz-Roy’s observations are so well distributed over the 
southern hemisphere, that a good view of the changes which the 
variation is undergoing throughout its meridians may be obtained 
by comparing his determinations with those of earlier observers at 
the same stations. The following table has been formed for the 
purpose of exhibiting such a comparison at all those stations where 
materials for it exist; and I may here remark how much such 
comparisons are facilitated by the valuable collection of early 
observations contained in the Appendix to the Magnetismus der 
Erde. 
Cars or Goop Horr. FaLKLAnp IsLanps. 
Observer. Date. Variation, Observer. Date. Variation. 
o} / ° 4 
Davis .. .. 1605 o. 30K. Freycinet se) | 1820) 19, 26 Es 
Keeling .. .. 1609 0. 12 W. Duperrey +. 18292 19. 07 E. 
Leydecker .. 1675 8. 28 W. Fitz-Roy.. .. 1833 19. 00 E. 
Mathews Sy AAG.) 22 We 
La Caille sed752- Ho. OWS Port Famt1ne. 
Wales .. .- 1772 20, 26 W. Wallis .. .. 1766 22. 30E 
Wales y-c 9.091775. 21.014 W. Carteret .. .. 1766 22, 22 FE. 
Bligh .. -. 1788 23. 16 W. Fitz-Roy.. .. 1831 23. oo E. 
Dentrecasteaux 1792 24. 30 W. 
Freycinet .. 1818 26. 31 W. ConcEP¢ION. 
Fitz-Roy .. 1836 28. 30 W. La Perouse .. 1786 15. 15 E. 
B. Hall .. | ..) 1820) 25.430 B. 
St. HELENA. Duperrey » 1823 16, 16 E. 
Mavise ly.) e)  ORO. 7.19 °R. Fitz-Roy.. .. 1835 16. 48 E. 
Halley .. -.. 1677 0. 40E. 
Halley Bie cites 0) MNGQR (e Ayy 0 Whe VALPARAISO, 
Mathews ne, A247 30 We Don G. Juan... 1744 12. 30 E. 
Wales .. « 1775 12. 18 W. Vancouver -- 1793 14. 49 E. 
Hunter .. .. 1789 15. 30 W. Tatitke ovis © se), 18277 Sa OO. 
Macdonald .. 1796 15. 48 W. Fitz-Roy.. -- 1835 15. 18 E. 
Krusenstern .. 1806 17. 18 W. 
Fitz-Roy  .. 1836 18. 00 W. CaLLao. 
Ulloa se, we 2740) 9, 02 E. 
Rio DE JANEIRO. Duperrey .- 1823 g. 30E. 
UO cs 1768 a. 94: Fitz-Roy.. .. 1835 10. 36E. 
Hunter .. .. 1787 6. 12E. 
Freycinet “Oagau!! a, 54 E. GavapaGcos IsLANDSs. 
Rumker .. .. 1821 9. 21 E. Vancouver -- 1794 8. oo BE. 
Erman .. .. 1830 2 10 £. B. Hall -.. «ic, 1821 9-8) 20%. 
Fitz- Roy -. 1836 2, oo E. Fitz-Roy.. .. 1835 9. 30E. 
