248 



ON THE PERIODICITY OF THE AURORA BOREALIS. 



*1729. 



# ii 



# u 



# <i 

 * 

 * 

 # 



# <i 



*1730. 



n 



it 



# 

 * 

 * 

 # 

 * 

 * 

 # 



* 

 * 

 * 

 # 

 * 

 * 

 * 

 # 



# 

 * 

 * 



# 

 » 



* 



# 

 * 

 * 

 * 

 * 

 * 

 * 

 * 



# 



# 

 * 



a 



Oct. 13. 



" 17. 



" 24. 



Nov. 16. 



« 16. 



" 16. 



« 16. 



Dec. 17. 



Jan. 16. 



Feb. 7. 



" 15. 



" 15. 



" 16. 



" 18. 



March 6. 



6. 



" 9. 



" 9. 



" 17. 



" 18. 



April 12. 



" 13. 



" 20. 



.May 9. 



June 21. 



July 5. 



6. 



'• 17. 



" 19. 



Aug. 



Sept. 28. 



« 30. 



" 30. 



4. 



5. 



6. 



7. 



9. 



11. 



20. 



21. 



22. 



24. 



26. 



2. 



2. 



3. 



Oct. 



Nov. 



Paris. Maraldi. 

 Germany. Frobes. 



Germany. Frobes. 

 Germany. Frobes. Reuss. 

 Paris. Maraldi. Risinge. Laurel. 

 Hudiksvall. Bromann. 

 Lunda. Quenselius. 

 Gi rmany. Frobes. 

 Germany. Frobes. 1 

 Germany. Frobes. 

 Germany. Frobes. 

 Reuss. Thompson. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 France. Reuss. 

 Germany. Frobes. 

 St. Petersburg. Kraft. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. Lusatia. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. Lbbau. 

 Germany. Frobes. 

 Germany. Frobes. 

 Sin m. Frobes. 

 Germany. Frobes. 

 '////. Frobes. 

 Risinge. Laurel. 

 Germany. Frobes. 

 Germ i nn/. 

 Germany. 



G. rmany. 

 Germany. 

 Germany. 



Germany. 

 German)/. 

 Germany. 

 Pilgram. 

 Germany. 



Mark. Beckmann. 

 Germany. Frobes, 

 France. Frobes. 



France. 



Frobes. 

 Frobes. 

 Frobes. 

 Frobes. 

 Frobes. 

 Frobes. 

 Frobes. 

 Frobes. Reuss. 



Frobes. 



*1730. Nov. 5. 



Pilgram. 



) Bueclmer. Miscell. Phys. Med. Math. 1730, pp. 824, etc. 



* 11 



* a 



* a 



* it 



* l< 



* II 



* II 



* ii 



* ii 



*1731. 



* ci 



* ii 



* a 



* it 



* ii 



* ii 



* « 



* ii 



*1732. 



* i< 



* ii 



* ii 



* a 



* ii 



* ii 



* a 



* « 



* u 



* ii 



* tt 



* ii 



* ii 



* ii 



* ii 



* ii 



* ii 



* ii 



* i. 



* ii 

 ii 



*1733. 



* ii 



*1734. 



Dec. 



Oct. 



Nov 



Jan 



t. 



8. 

 19. 

 28. 



8. 

 17. 

 23. 

 26. 

 28. 



3. 



4. 



7. 



7. 



8. 



23. 

 29. 



11. 

 3. 



" 18. 

 Feb. 20. 



ii 21. 

 Mar. 14. 



" 18. 



ii 21. 



" 22. 



" 28. 



" 28. 

 June 26. 

 Aug. 22. 



" 23. 

 Sept. 10. 



" 23. 



" 24. 



" 25. 



" 26. 

 Oct. 23. 

 Nov. 12. 



" 20. 

 Dec. 4. 

 April 13. 

 July 7. 

 Sept. 19. 



Germany. Frolics. Pilgram. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 G( rmany. Frobes. 

 Germany. Frobes. 

 Germ a ay. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germ my. Frobes. 

 Helmstadt. Frobes. 

 ]I< hnstadl. Frobes. 

 Hn> . 3tei len. 



tadt. Frobes. 

 Helmstadt. Frobes. Thompson. 

 Marl. Beckmann. 

 Helmstadt. Frobes. 

 Helmstadt. Frobes. 

 Helmut all. Frobes. 1 

 Hudiksvall, Sweden. 

 Hudiksvall, Sweden. 

 Germany. Frobes. 

 ' Frobes. 



Germany. Frobi 3. 

 Germany. Frobes. 

 Germany. H lm <la<ll. Frobes. 

 Germany. Helmstadt. Frobes. 

 Strengru -• i, Haneslroem. 

 < lllonberg. 



Germany. Helmstadt. Frobes. 

 Germany. Frobes. 

 Germany. Goburg. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 Germany. Helmstadt. Frobes. 

 Germany. Frobes. 

 Germany. Frobes. 

 Mairan. 2 



Silesia. Frobes. 8 

 Leipsic. Gottsched. 

 Allorf. Kelschius. 



i Condamine, while making a journey from Cyprus to Con- 

 stantinople, saw the aurora frequently in Sept. and Oct., 1731. 

 ? Me'm. de l'Acad. 1733. p. 47* 

 :; Nova Litter. Eips. 1733, p. 291, etc. 



