OF THE PERIODICITY OF TOE AURORA BOREALIS. 



Oct. 9. Mairan, Short, and Phil. Trans. 



" 9. Gottingen. Hollmann. 



" 10. Upsal. Celsius and Iliorter. 



" 10. St. Petersburg. Kraft. Mairan and Short. 



" 11. Upsal. Celsius and Hiorter. 



" 12. Upsal. Celsius and Hiorter. 



" 12. St. Petersburg. Kraft. Mairan and Short. 



" 13. Upsal. Celsius and Iliorter. 1 



" 14. Upsal. Celsius and Hiorter. 



" 14. Mairan and Short. 



" 15. Upsal. Celsius and Hiorter. 



" 15. Mairan and Short. 



" 1G. Upsal. Celsius and Hiorter. 



" 17. Upsal. Celsius and Hiorter. 



" 19. Upsal. Celsius and Iliorter. 



" 28. St. Petersburg. Kraft. 



Nov. 2. Wittemberg. Weidler. 2 Mairan. 



" 4. Upsal. Celsius and Iliorter. 



" 6. Upsal. Celsius and Iliorter. 



" 9. Wittemberg. Weidler. Mairan. 



" 11. Upsal. Celsius and Hiorter. . 



" 11. Mairan and Short. 



" 12. St. Petersburg. Kraft. 



" 12. Upsal. Celsius and Iliorter." 



" 14. Upsal. Celsius and Hiorter. 



" 14. St. Petersburg. Kraft. 



" 17. Upsal. Celsius and Iliorter. 



" 29. Upsal. Celsius and Iliorter. 



Dec. 1. Upsal. Celsius and Iliorter. 



" 2. Upsal. Celsius and Hiorter. 4 



" 3. Upsal. Celsius and Iliorter. 1 



" 4. St. Petersburg. Kraft. 



" 4. Upsal. Celsius and Iliorter. 



" 7. Upsal. Celsius and Iliorter. 



" 8. St. Petersburg. Kraft. 



" 8. Upsal. Celsius and Iliorter. 



" 1 2. Upsal. Celsius and Iliorter. 



" 17. Upsal. Celsius and Iliorter. 



" 18. Upsal. Celsius and Hiorter. 



" 21. St. Petersburg. Kraft. 



" 21. Upsal. Celsius and Iliorter. 6 



1742. 

 Jan. 2. Mairan and Short. 



'• Neither this nor the next is in Acta Soc. Upsal. 



2 Mairan gives this and that of Nov. 9 in Weidler's special 

 catalogue, but not in his own general catalogue. Compare pages 

 503 and 545 of his Traite' &c. 



3 Not in Svenska Vetensk. Acad. 



4 Not in Svenska Vetensk. Acad. 

 6 Not in Svenska Vetensk. Acad. 



Jan. 3. 



9. 



Feb. 2. 



" 4. 



9. 



" 10. 



" 11. 



" 15. 



" 25. 



" 2G. 



1. 



Mar 



St. Petersburg. Kraft. 



Upsal. Celsius. 1 



Upsal. Celsius. 2 



Upsal. Celsius. 



Upsal. Celsius. 



Upsal. Celsius. 



Upsal. Celsius. 



Upsal. Celsius. 



Wittemberg. Weidler. Mairan. 



Upsal. Celsius. 



St. Petersburg. Kraft. 8 



Wittemberg. Weidler. Mairan. 



Plymouth. Huxhani. Siberia. Gmelin 



Upsal. Celsius. 



Upsal. Celsius. 



Upsal. Celsius. St. Petersburg. Kraft. 



St. Petersburg. Kraft. 



Upsal. Celsius. Plymouth. Huxham. 



Plymouth. Huxham. 



Upsal. Celsius. 



Upsal. Celsius. 



St. Petersburg. Kraft. 



Plymouth. Huxham. 



Wittemberg. Weidler. Mairan. 



St. Petersburg. Kraft. 



Upsal. Celsius. Plymouth. Huxham. 



Wittemberg. Weidler. Mairan. 



St. Petersburg. Kraft. 



Siberia. Gmelin. 



Plymouth. Huxham. 



St. Petersburg. Kraft. 



Kraft. 



Kraft. 



Kraft. 



Kraft. 



Kraft. 



St. Petersburg. 



St. Petersburg. 



St. Petersburg. 



St. Petersburg. 



St. Petersburg. 



Cambridge. Winthron. 5 



Upsal. Celsius. 



St. Petersburg. Kraft. 



Upsal. Celsius. 



Wittemberg. AVe idler. 



Upsal. Celsius. 



Upsal. Celsius. 



Upsal. Celsius. 



Upsal. Celsius. St. Petersburg 



1 Not in Acta Soc. Upsal. 



2 Svenska Vetensk. Acad. IV. 54. 

 8 Comm. Petrop. XIV. 241. 



4 N. Comm. Petrop. XI. 323. 

 6 Amer. Jour., XL. 2(14. 



St. Petersburg. Kraft. 

 Siberia. Gmelin. 

 Mairan. 



Kraft. 



