ON THE PERIODICITY OF THE AURORA BOREALIS. 



131 



u 

 « 



u 



Nov. 12. 

 " 12. 

 " 13. 

 " 14. 

 " 15. 

 " 15. 

 " 17. 

 " 17. 

 " 18. 

 " 18. 



18. 



18. 



18. 

 " 19. 

 " 19. 

 " 20. 

 " 21. 

 « 23. 

 " 28. 

 Dec. 1. 

 " 2. 

 « 3. 

 " 3. 

 " 4. 

 « 5. 

 « 6. 

 « 7. 

 " 8. 

 « 9. 

 " 10. 

 " 11. 

 " 12. 

 " 13. 

 " 14. 

 « 14. 

 " 14. 

 " 15. 

 " 15. 

 " 16. 

 " 17. 

 " 17. 

 " 17. 



18. 



19. 



19. 



19. 



20. 



Paris. Laugier. Arago. Gothaab. Block. 

 Christiania. Hansteen. Jakobshavn. Rudolph, 

 Christiania. Hansteen. Gothaab. Block. 

 Christiania. Hansteen. Gothaab. Block. 

 New Haven. Herrick. Newton and Loomis, 

 Jakobshavn. Rudolph. Gothaab. Block. 

 New York. Hough. Christiania. Hansteen. 

 Jakobshavn. Rudolph. Gothaab. Block. 

 Cambridge. Lovering. Providence. Caswell. 

 New Haven. Herrick. Newton and Loomis. 

 New York. Hough. Toronto. Sabine. 

 Brussels. Quetelet. Gothaab. Block. 

 Christiania. Hansteen. Dunse. Stevenson. 

 Christiania. Hansteen. Dunse. Stevenson. 

 Jakobshavn. Rudolph. 

 Gothaab. Block. 

 Gothaab. Block. 

 Gothaab. Block. 

 Gothaab. Block. 

 Gothaab. Block. 

 Gothaab. Block. 

 Christiania. Hansteen. 

 Jakobshavn. Rudolph. 

 Gothaab. Block. Jakobshavn, 

 Gothaab. Block. 

 Gothaab. Block. 

 Gothaab. Block. 



Bogoslowski. Kupffer. Gothaab. Block. 

 Christiania. Hansteen. Gothaab. Block. 

 Gothaab. Block. 

 Gothaab. Block. 



Paris. Boud. 1 Gothaab. Block. 

 Paris. Boue\ Gothaab. Block. 

 New Haven. Herrick. Newton and Loomis. 

 New York. Hough. Gothaab. Block. 

 Christiania. Hansteen. Dunse. Stevenson. 

 New Haven. Herrick. Newton and Loomis. 

 Gothaab. Block. 



Gothaab. Block. Jakobshavn. Rudolph. 

 Toronto. Sabine. Dunse. Stevenson. 

 Hobarton, V. D. Land. Sabine. 2 

 Gothaab. Block. 

 Gothaab. Block. 

 Cambridge. Bond. 

 Cracow. Weisse. 

 Gothaab. Block. 

 Cracow. "Weisse. 8 



Gothaab. Block. 



Rudolph. 



Lovering. 

 Christiania. 



Hansten. 



l Ku. ^ du Monde Savant, 1841, p. 728. 



a Aurora Australis. 8 Bull, de l'Acad. Brux. IX. Pt. I. p. 14. 



Dec. 21. 

 « 24. 



" 24. 

 " 27. 

 " 30. 

 " 31. 



Jan. 1. 

 " 2. 

 " 2. 

 " 3. 

 " 4. 

 " 5. 



6. 

 " 6. 



7. 

 " 8. 



8. 

 " 9. 

 " 9. 

 " 11. 

 " 11. 

 " 11. 

 " 12. 

 " 12. 

 " 13. 

 " 14. 

 " 15. 

 " 15. 

 " 15. 

 " 15. 

 " 15. 

 " 15. 

 " 16. 

 " 17. 

 « 18. 

 " 20. 

 " 20. 

 " 24. 

 " 31. 

 Feb. 1. 



1. 

 " 2. 

 " 3. 

 « 4. 



Cambridge. Bond. Lovering. 



Cambridge. Lovering. 



New Haven? Herrick. Newton and Loomis. 



Gothaab. Block. 



Gothaab. Block. 



Gothaab. Block. 



1842. 



Jakobshi 



Rudolpl 



Gothaab. Block. 



Hobarton. Sabine. 1 

 Gothaab. Block. 

 Worcester, Mass. "Woodward. 2 

 Gothaab. Block. 

 Cambridge. Lovering. 

 Lovering. 

 Hansteen. 

 Rudolph. 

 Lovering. 

 Herrick. Newton and Loomis. 

 Gothaab. Block. Jakobshavn. Rudolph. 

 Cambridge. Lovering. Gothaab. Block. 

 Herrick. Newton and Loomis. 

 Bond. Lovering. 

 Hough. Newberry. Johnson. 

 Gothaab. Block. 

 Lovering. 



Cambridge 

 Christiania, 

 Jakobshavn. 

 Cambridge. 

 St. Louis. 



New Haven ' 



Cambridge. 



New York. 



Toronto. Sabine. 



Cambridge. Bond. 



Gothaab. Block. 



Gothaab. Block. 



Gothaab. Block. 



Cambridge. Lovering. Worcester. "Woodward. 



Washington, D. C. Gilliss. 



New Haven. Herrick. Newton and Loomis. 



New York. Hough. Canada. 



Newberry. Johnson. Providence. Caswell. 



Christiania. Hansteen. Gothaab. Block. 



Gothaab. Block. 



Gothaab. Block. 



Gothaab. Block. 



New Haven f Herrick. Newton and Loomis. 



Gothaab. Block. 



St. Petersburg. Kupffer. 



Gothaab. Block. 



New York. Hough. 



Hobarton. Sabine. 1 Gothaab. Block. 



Worcester. "Woodward. Gothaab. Block. 



Gothaab. Block. 



Gothaab. Block. 



1 Aurora Australis. 



2 Med. and Surg. Journ. Boston, XXVI. 36, 83, 228 and 391. 



