in the above-mentioned Seventh Report of the British Association for the Advancement of Science.
We are indebted for the great number of magnetic observations in the Russian Empire, and in the neighbouring parts of China, to
Hansteen. (Poggendorff's Annals.)
Erman. (Reise um die Erde, and manuscript communications.)
Von Humboldt. (Voyage aux régions équinoxiales, T. 13.)
Fuss. (Mémoires de l'Académie des Sciences de St. Petersbourg, Sixième Série.)
Fedor. (Communicated in manuscript, through Struve).
Reinke. (Observations Météorologiques et Magnétiques, faites dans l'étendue de l'Empire de Russie, redigées par A. T. Kupffer, Nr. II.)
At the following places a mean has been taken of the determinations of several observers. The differences between them are sometimes greater than can be attributed to yearly changes.
| 12. Tobolsk. | ||
| Declination. | Hansteen, 1828, | − 9° 58′ |
| Erman, 1828, | − 9 47 | |
| Fuss, 1830, | − 11 52 | |
| Fedor, 1833, | − 10 20 | |
| Inclination. | Erman, 1828, | 71 7 |
| Von Humboldt, 1829, | 70 56 | |
| Fuss, 1830, | 71 1 | |
| Fedor, 1833, | 71 2 | |
| 16. Catharinenburg. | ||
| Declination. | Hansteen, 1828, | − 6° 27′ |
| Erman, 1828, | − 7 23 | |
| Reinke, 1836, | − 5 5 | |
| Inclination. | Erman, 1828, | 69 24 |
| Von Humboldt, 1829, | 69 6 | |
| Fuss, 1830, | 69 19 | |
| Fedor, 1832, | 69 15 | |
| 17. Tomsk. | ||
| Declination. | Hansteen, 1828, | − 8° 32′ |
| Erman, 1829, | − 8 36 | |
| Inclination. | Erman, 1829, | 70 59 |
| Fuss, 1830, | 70 51 | |
