ON THE PERIODICITY OF THE AURORA BOREALIS. 



157 



Mar. 1 1 . Baltischport. Kupffer. 



" 1 2. Christiania. Hansteen. 



" 13. Fort Norman. Hooper. 



" 1 3. Christiania. Hansteen. Jakobshavn. Rudolph. 



" 14. Fort Norman. Hooper. 



" 15. Fort Norman. Hooper. 



" 16. New York. Hough. Fort Norman. Hooper. 



" 16. Christiania. Hansteen. 



" 17. Fort Norman. Hooper. 



" 18. New York. Hough. 



" 21. Fort Norman. Hooper. 



" 22. New York. Hough. Fort Norman. Hooper. 



" 25. New York. Hough. 



" 26. New York. Hough. 



" 29. New York. Hough. 



" 31. Providence, R. I. Caswell. 



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



" 31. New York. Hough. Litchfield. Hough. 



Apr. 1. Christiania. Hansteen. 



" 2. Cambridge. Bond. Lovering. 



" 2. Fort Norman. Hooper. 



" 3. Fort Norman. Hooper. 



" 4. Fort Norman. Hooper. 



" 6. Cambridge. Bond. Lovering. 



" 6. Worcester. Chandler. 1 



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



" 6. Providence. Caswell. New York. Hough. 



" 6. Fort Norman. Hooper. Sitka. Kupffer. 



" 7. Cambridge. Bond. Lovering. 



" 7. Providence, TL. I. Caswell. 



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



" 7. New York. Hough. Litchfield. Hough. 



" 8. New York. Hough. Fort Norman. Hooper. 



" 9. New York. Hough. 



" 14. New York. Hough. 



" 15. New York. Hough. 



" 17. New York. Hough. 



" 19. New York. Hough. 



" 28. Fort Norman. Hooper. 



" 30. Fort Norman. Hooper. 



May 3. Christiania. Hansteen. 



" 7. Cambridge. Bond. Lovering. 



" 7. Worcester. Chandler. 



" 7. New Haven. Herwck. Newton and Loomis. 



" 7. Providence. Caswell. New York. Hough. 



" 9. New York. Hough. 



" 10. New York. Hough. Litchfield. Hough. 



" 12. Worcester. Chandler. Providence. Caswell. 



1 Eighteenth Report of the Lunatic Asylum, p 64. 



