ON THE PERIODICITY OP THE AURORA BOREALIS. 



137 



Jan. 31. 

 Feb. 4. 



5. 



6. 



7. 



7. 



9. 

 11. 

 11. 

 12. 

 12. 

 13. 

 15. 

 16. 

 17. 

 17. 

 17. 

 20. 

 21. 

 22. 

 23. 

 26. 

 28. 

 Mar. 2. 



4. 



7. 



7. 



8. 



9. 



9. 

 10. 

 11. 

 12. 

 13. 

 16. 

 17. 

 19. 

 20. 

 21. 

 23. 

 24. 

 29. 

 31. 

 Apr. 1. 



2. 



3. 



5. 



Lake Athabasca. Lefroy. 



New York. Hough. 



Lake Athabasca. Lefroy. 



Gothaab. Block. 



Lake Athabasca. Lefroy. 



Makerstoun. Broun. 



Jakobshavn. Rudolph. 



New Haven ? Herrick. Newton and Loomis. 



Lake Athabasca. Lefroy. Gothaab. Block. 



Lake Athabasca. Lefroy. 



Makerstoun. Broun. 



Lake Athabasca. Lefroy. 



Lake Athabasca. Lefroy. Gothaab. Block. 



Lake Athabasca. Lefroy. Gothaab. Block. 



Lake Athabasca. Lefroy. 



Jakobshavn. Rudolph. 



Christiania. Hansteen. Gothaab. Block. 



Hamburg. Schmidt. Lake Athabasca. Lefroy. 



Lake Athabasca. Lefroy. 



Makerstoun. Broun. Gothaab. Block. 



Gothaab. Block. 



Lake Athabasca. Lefroy. 



Lake Athabasca. Lefroy. Gothaab. Block. 



Makerstoun. Broun. Toronto. Sabine. 



New Haven ? Herrick. Newton and Loomis. 



New York. Hough. 



Christiania. Hansteen. 



New York. Hough. 



New York. Hough. 



Jakobshavn. Rudolph. 



Gothaab. Block. 



Gothaab. Block. 



Toronto. Sabine. 1 

 Makerstoun. Broun. 

 Gothaab. Block. 

 Makerstoun. Broun. 



Makerstoun. Broun. 



Gothaab. Block. 



Gothaab. Block. 



Christiania. Hansteen 



Christiania. 



Christiania. 



Christiania. 



New York. 



New York. 



Newberry. 



Gothaab. Block. 



Gothaab. Block. 



Hansteen. 

 Hansteen. 

 Hansteen. 

 Hough. Gothaab. 

 Hough. 

 Johnson. Makerstoun 



Gothaab. Block. 



Block. 



Broun. 



Christiania. Hansteen. 



Fort Simpson. Lefroy. 3 



Fort Simpson. Lefroy. 



Fort Simpson. Lefroy. Gothaab. Block. 



Cambridge. Bond. Levering. 



Magnet, and Meteor. Observ. Toronto, II. 336. 

 2 Magnet, and Meteor. Observ. at LakeA thabasea, &c.p. 179. 



VOL. X. 18 



Apr. 5. 

 5. 



" 5. 

 6. 



" 7. 



" 9. 



" 10. 



" 11. 



" 13. 



" 14. 



" 15. 



" 16. 



" 16. 



" 17. 



" 17. 



" 17. 



" 17. 



" 17. 



" 18. 



" 19. 



" 19. 



" 20. 



" 21. 



" 25. 



" 28. 



May 2. 



4. 



" 5. 



" 7. 



" 8. 

 8. 



" 8. 



" 14. 



" 21. 



" 22. 



" 22. 



" 22. 



" 25. 

 June 12. 



" 16. 



" 22. 

 July 8. 

 Aug. 1. 



" 1. 



" 3. 



« 9. 



" 9. 



New Haven. Herrick. Newton and Loomis. 



New York. Hough. Fort Simpson. Lefroy. 



Makerstoun. Brouu. Gothaab. Block. 



Fort Simpson. Lefroy. Gothaab. Block. 



Fort Simj)son. Lefroy. Gothaab. Block. 



Fort Simpson. Lefroy. 



Fort Simpson. Lefroy. Makerstoun. Broun. 



Fort Simpson. Lefroy. 



Fort Simpson. Lefroy. 



Fort Simpson. Lefroy. 



Fort Simpson. Lefroy. 



Fort Simpson. Lefroy. Toronto. Sabine. 



Hobarton, Van Dieman's Land. Sabine. 



Cambridge. Bond. Lovering. 



Philadelphia. Bache. 



New York. Hough. Fort Simpson. Lefroy. 



Hamburg. Schmidt. Makerstoun. Broun. 



Christiania. Hansteen. 



Fort Simpson. Lefroy. 



New York. Hough. Fort Simpson. Lefroy. 



Gothaab. Block. 



Fort Simpson. Lefroy. 



Lefroy. Hobarton. Sabine. 1 



Lefroy. 



Lefroy. 



Lefroy. 

 Hough. Fort Simpson. Lefroy. 

 Hough. Fort Simpson. Lefroy. 



Fort Simpson. 

 Fort Simpson. 

 Fort Simpson. 

 Fort Simpson. 

 New York. 

 New York. 

 Toronto. Sabine. 

 Cambridge. Bond 

 New York. 

 Makerstoun. 

 New York. 

 Makerstoun. 

 New Haven. 

 New York. 

 Makerstoun. 



Lovering. 

 Toronto. 



Sabine. 



Toronto. Sabine. 



Newton and Loomis. 

 Toronto. Sabine. 



Sabine. 



Hough. 



Broun. 

 Hough. 



Broun. 



Herrick. 

 Hough. 



Broun. 

 Hobarton, Van Dieman's Land. 

 Providence, R. I. Caswell. 

 New York. Hough. 



New Haven ? Herrick. Newton and Loomis. 

 New York. Hough. 

 New York. Hough. 

 Christiania. Hansteen. 

 Makerstoun. Broun. 

 Nantucket. Mitchell. Herrick. 2 

 Toronto. Sabine. Makerstoun. Broun. 



England. Hough. 



1 Magnet, and Meteor. Observ. Hobarton, II. p. 326. 



2 Bull, de l'Acad. Brux. xii. Pt. I. p. 534. 



