OF THE PERIODICITY OF THE AURORA BOREALIS. 



61 



Nov. 8. Lubeck. Behn. Bout;. 1 



" 24. St. Petersburg. Euler. 



" 26. Lubeck. Behn. St. Petersburg. Euler. 



Dec. 17. Jena. Zeissing. 



" 24. Jena. Zeissing. 



1771. 



Jan. 6. Berlin. Beguelin. 



" 15. Berlin. Beguelin. 



" 18. Berlin. Beguelin. 



" 20. Berlin. Beguelin. 



" 26. St. Petersburg. Euler. 2 



Feb. 7. St. Petersburg. Euler. 



" 8. St. Petersburg. Euler. 



" 9. Berlin. Beguelin. 



10. Berlin. Beguelin. 



15. Berlin. Beguelin. 



19. Cambridge. Wintbrop. Lovering. 



19. Berlin. Beguelin. St. Petersburg. Euler. 



" 19. Montmorenci. Paris. Franeker. Cotte. 8 



" 20. Montmorenci. Cotte. 



Mar. 2. St. Petersburg. Euler. 



" 13. St. Petersburg. Euler. Berlin. Beguelin. 



" 13. Montmorenci. Franeker. Cotte. 



" 14. St. Petersburg. Euler. 



" 15. St. Petersburg. Euler. 



" 16. St. Petersburg. Euler. 



" 17. Cambridge. Wintbrop. Lovering. 



" 17. St. Petersburg. Euler. 



" 18. Cambridge. Winthrop. Lovering. 



" 23. St. Petersburg. Euler. 



" 30. Paris. Boue. 



Apr. 2. St. Petersburg. Euler. 



" 4. Berlin. Beguelin. 



" 5. Berlin. Beguelin. Montmorenci. Cotte. 



" 15. Berlin. Beguelin. Montmorenci. Cotte. 



May 2. Berlin. Beguelin. 



" 3. Berlin. Beguehn. 



" 6 ? Berlin. Beguelin. 



" 7. Berlin. Beguelin. 



" 8. Berlin. Beguelin. 



« 12. St. Petersburg. Euler. 



" 12. Franeker. Cotte. Jena. Zeissing. 



" 13. St. Petersburg. Euler. Franeker. Cotte. 



June 2. Cambridge. "Wintbrop. Lovering. 



" 2. Lubeck. Behn. Boue. 



1 In the Chateau de Saintes en Hainaut, three auroras were ob- 

 served in 1770. Me'm. de l'Acad. Brux. I. 554. 



2 N. Comm. Petrop. XVI. 695. 

 8 Mem. de Met. I. 



' ambridge. Wintbrop. Lovering. 



St. Petersburg. Euler. 



Berlin. Beguelin. 



Berlin. Beguelin. 



St. Petersburg. Euler. 



Cambridge. Winthrop. Lovering. 



Cambridge. Wintbrop. Lovering. 



Franeker. Cotte. 



St. Petersburg. Euler. 



St. Petersburg. Euler. 



Cambridge. Winthrop. Lovering. 



Cambridge. Wintbrop. Lovering. 



iSif. Petersburg. Euler. 



St. Petersburg. Euler. 



Cambridge. Winthrop. Lovering. 



Franeker. Cotte. 



Berlin. Beguelin. 



St. Petersburg. Euler. Berlin. Beguelin. 



St. Petersburg. Euler. 



Berlin. Beguelin. Franeker. Cotte. 



Cambridge. Winthrop. Lovering. 



St. Petersburg. Euler. 



St. Petersburg. Euler. 



Cambridge. Winthrop. Lovering. 



Franeker. Cotte. 



St. Petersburg. Euler. 



St. Petersburg. Euler. 



Cambridge. Winthrop. Lovering. 



Cambridge. Winthrop. Lovering. 



Berlin. Beguelin. 



Franeker. Cotte. 



Berlin, Beguelin. 



Cambridge. Winthrop. Lovering. 



Franeker. Cotte. 



St. Petersburg. Euler. 



1772. 



Berlin. Beguelin. 



Berlin. Beguelin. 



Bradford, Mass. Wilbams. 1 



St. Petersburg. Euler. 



St. Petersburg. Euler. 



St. Petersburg. Euler. 2 



Bradford, Mass. Williams. 



Berlin. Beguelin. Franeker. Cotte. 



St. Petersburg. Euler. 



Marseilles. Cotte. 



St. Petersburg. Euler. 



1 Amer. Phil. Soc. II. 11 S. 



2 N. Comm. Petrop. XVII. 717 



