144 



ON THE PERIODICITY OF THE AURORA BOREALIS. 



Jan. 8. 



" 11. 



" 12. 



« 13. 



" 13. 



" 14. 



« 16. 



« 17. 



" 17. 



" 17. 



" 18. 



" 20. 



" 21. 



" 25. 



" 2G. 



" 28. 



" 30. 



Feb. 5. 



C. 



" 6. 

 6. 



" 6. 



" 7. 



" 9? 



" 10. 



" 21. 



" 22. 

 Mar. 1. 



" 4. 



" 5. 



" 6. 

 8. 



8. 



9. 

 10. 

 11. 

 12. 

 13. 

 14. 

 15. 

 17. 

 17. 

 18. 

 19. 

 19. 

 19. 

 19. 

 19. 

 19. 



Jakobshavn. Rudolph. 



Repulse Bay. Rae. 



Repulse Bay. Rae. Jakobshavn. Rudolph. 



Bonn. Schmidt. Christiania. Hansteen. 



Repulse Bay. Rae. 



Bonn. Schmidt. Repulse Bay. Rae. 



Repulse Bay. Rae. 



New Haven ? Herrick. Newton and Loomis. 



New Fork. Hough. 



Repulse Bay. Rae. Jakobshavn. Rudolph. 



Repulse Bay. Rae. Jakobshavn. Rudolph. 



Christiania. Hansteen. 



New Haven ? Herrick. Newton and Loomis. 



New York. Hough. 



Repulse Bay. Rae. 



Repulse Bay. Rae. 



Makersioun. Broun. Dunse. Stevenson. 



Jakobshavn. Rudolph. 



Cambridge. Bond. Lovering. 



New Haven ? Herrick. Newton and Loomis. 



Makersioun. Broun. Dunse. Stevenson. 



Jakobshavn. Rudolph. 



New Haven ? Herrick. Newton and Loomis. 



Repulse Bay. Rae. 



Repulse Bay. Rae. 



New York. Hough. Jakobshavn. Rudolph. 



Cliristiania. Hansteen. Toronto. Sabine. 



Christiania. Hansteen. 



New York. Hough. Christiania. Hansteen. 



New York. Hough. 



New York. Hough. 



Cambridge. Bond. Lovering. 



New Haven. Herrick. Newton and Loomis. 



Newberry. Johnson. 



Jakobshavn. Rudolph. 



Christiania. Hansteen. 



New Haven? Herrick. Newton and Loomis. 



Christiania. Hansteen. Jakobshavn. Rudolph. 



Christiania. Hansteen. 



Jakobshavn. Rudolph. 



New York. Hough. 



New Haven ? Herrick. Newton and Loomis. 



Rutin. Schmidt. 



New York. Hough. 



Cambridge. Bond. Lovering. 



New Haven. Herrick. Newton and Loomis. 



Newberry. Johnson. New York. Hough. 



Boston. Washington, D. C. Hough. 



Toronto. Sabine. 



Providence, R. I. Caswell. 



Mar. 19. Brussels. Quetelet. Buxton. Mann. 1 



" 19. London. Adams. Amsterdam, fyc. 2 



" 19. Cambridge, Eng. Challis and Potter. 



" 19. Makerstoun. Broun. 



" 22. New York. Hough. 



" 28. New York. Hough. 



Apr. 3. New York. Hough. Christiania. Hansteen. 



" 3. Makerstoun. Broun. Repidse Bay. Rae. 



" 4. New York. Hough. 



" 6. New York. Hough. 



" 7. Cambridge. Bond. Lovering. 



" 7. Boston. Hale. Lovering. 



" 7. New Haven. Herrick. Newton and Loomis. 8 



" 7. Washington and Baltimore. Hough. 



" 7. Neio York. Hough. Toronto. Sabine. 



" 8. Toronto. Sabine. 



" 10. New York. Hough. 



" 11. New York. Hough. 



" 13. Christiania. Hansteen. 



" 14. Christiania. Hansteen. 



" 15. Christiania. Hansteen. 



" 16. Cambridge. Bond. Lovering. 



" 16. Christiania. Hansteen. 



" 19. Toronto. Sabine. 



" 20. Hobarton, Van Dieman's Land. Sabine. 4 



" 21. Christiania. Hansteen. Hobarton. Sabine. 



May 7. New York. Hough. Toronto. Sabine. 



" 9. New York. Hough. 



" 15. Cambridge. Bond. Lovering. 



" 15. New York. Hough. Providence. Caswell. 



" 15. New Haven. Herrick. Newton and Loomis. 



" 15. Sitka. Kupffer. 5 



June 6. Brussels. Quetelet. 



" 12. New Haven ? Herrick. Newton and Loomis. 



" 12. New York. Hough. Newberry. Johnson. 



" 12. Providence. Caswell. Toronto. Sabine. 



July 9. New Haven. Herrick. Newton and Loomis. 



" 9. New York. Hough. Providence. Caswell. 



" 9. Toronto. Sabine. 



" 11. New Haven. Herrick. Newton and Loomis. 



" 11. New York. Hough. Toronto. Sabine. 



" 12. New York. Hough. 



Aug. 3. Cambridge. Bond. Lovering. 



" 3. New York. Hough. 



" 4. New Haven. Herrick. Newton and Loomis. 



1 Athenseum, 1847, p. 335. 



2 Proc. Brit. Assoc. XVI. 7. 



3 Amer. Journ. Sci. New Series. III. 440. 



* Magnet, and Meteor. Observ. Hobarton, III. 324. 



6 Annal. de l'Observ. Phys. Centrale de Russie, 1848, p. 373. 



