ON THE PERIODICITY OF THE AURORA BOREALIS. 



249 



1735 



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1736. 2 Feb 



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 - II 



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*1737. 



# « 



# « 



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Man! i 2. 



" 13. 



" 15. 



" 22. 



" 24. 



" 24. 



" 24. 

 April 22. 



'• 23. 

 Sept. 25. 

 Oct. 15. 

 Nov. 18. 

 Dec. S. 



(i 13. 



" 15. 



" ,y 2. 

 9. 



" 17. 



March 21. 



April 5. 



Sept. 29. 



Oct. 7. 



" 20. 



" 22 



" 26. 



" 26. 



" 27. 



" 27. 



« 28. 



" 28. 



" 29. 



" 30. 

 Nov. 24. 

 Aug. 20. 



" 23. 

 Sept. 22. 



" 22. 



Oct. 23. 



" 28. 



Nov. 12. 



Dee. 5. 



" 16. 



Mark. Beckmann. 



Baraterio. 



Baraterio. 



Wittemberg. Kraus. 

 Wittemberg. Kraus. 

 London. Bevis. 1 

 Mark. Beckmann. 

 Potsdam. Frobes. 

 Mark. Beckmann. 

 Reuss. 

 Reuss. 



Verden. Trumphius. 

 Verden. Trumphius. 

 Verden. Trumphius. 

 Verden. Trumpliius. 

 Reuss. 



Mark. Beckmann. 

 Kelschius. 

 Mark. Beckmann. 

 Beckmann. 

 Beckmann. 

 Beckmann. 

 Beckmann. 

 Albrecht. 

 Albrecht. 

 Beckmann. 

 Albrecht. 

 Beckmann. 

 Albrecht. 

 Pomerania. Burghart. 

 Goburg. Albrecht. 

 Albrecht. 

 Albrecht. 

 Beckmann. 

 Beckmann. 

 Beckmann. 

 Goslar, Hanover. Henning. 

 Mark. Beckmann. 

 Siberia. Gmelin. 8 

 Mark. Beckmann. 

 Phil. Trans. LXI. 371. 

 Helmstadt. Frobes. Reuss. 



Mark. 



Mark. 



Mark. 



Mark. 



Goburg. 



Goburg. 



Mark. 



Goburg. 



Mark. 



Goburg. 



Goburg. 

 Goburg. 

 Mark. 



Mark. 

 Mark. 



' Phil. Trans. XLI. 347. 



- In Wochenscrift fur Astronomic etc., VII. 230, it is printed, 

 evidently by mistake, 1739. Tlie year 1741 is also printed for 

 1740, and 1737 and 1738 for 1747 and 1748. 



a Reise durcli Sibirien, 1733 bis 1743, II. 607. 



*1737. 



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*1739. 



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1740. 



a 



*1741. 



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1742. 



it 



1746. 



1747. 



*174S. 



1755. 



it 



*1759. 



* « 



*1761. 



1763. 



*1764. 



a 



*1765. 



Dec. 16. 



" 28. 

 " 30. 

 " 31. 

 Jan. 27. 

 Feb. 17. 

 " 27. 

 " 27. 

 March 10. 

 " 12. 

 " 22. 

 " 29. 

 " 29. 

 May 1. 

 June 2. 

 Sept. 24. 

 Oct. 31. 

 Jan. 22. 

 Feb. 21. 

 March 16. 

 Aug. 10. 

 Oct. 2. 

 " 8. 

 Jan. 16. 

 " 29. 

 Oct. 29. 

 Dec. 16. 

 Jan. 3. 

 " 6. 

 " 7. 

 Feb. 4. 

 " 8. 

 April 5. 

 Nov. 19. 

 Oct. 12. 

 March 4. 

 " 5. 

 Oct. 23. 

 " 12. 



Italy. Poleni. 



Goburg. Albrecht. 

 Island Chiloe. Paravey. 1 

 Spa/in. Feijoo. Rico. 

 Helmstadt. Frobes. 

 Helmstadt. Frobes. 

 Mark, Beckmann. 

 Helmstadt. Frobes. 

 Frobes. 

 Frobes. 

 Frobes. 



Frobes. Reuss. 

 Beckmann. 

 Beckmann. 



Helmstadt, 

 Helmstadt, 

 Helmstadt, 

 Helmstadt, 

 Mark. 

 Mark, 

 Reuss. 

 Mark. 

 Mark, 

 Mark. 

 Mark. 

 Mark, 

 Mark, 

 Mark. 

 Mark. 

 Upsal. 

 Mark. 



I '/ISIll. 



Mark. 

 Mark. 



Beckmann. 



Beckmann. 



Beckmann. 



Beckmann. 



Beckmann. 



Beckmann. 



Beckmann. 



Beckmann. 



Fischer. Wolf. a 



Beckmann. 



Fischer. 



Beckmann. 



Beckmann. 

 Venice? Zucconi. Wolf. 8 

 Venice. Zucconi. Wolf. 

 Berlin. Acad. Coll. 

 Paris. Acad. Coll. 4 

 Switzerland? Vogel. Wolf. 

 Switzerland? Vogel. Wolf. 

 Warsaw, Poland. AVolfe. 6 

 London* 

 Oxford, Lisbon. 

 Bergmann. Wolf. 7 

 Paris. Messier. Wolf. 8 



VOL. X. 



32 



1 Pogg. Ann. der Physik un d ei. Chem Erganzungsband 

 IV. 76. 



2 Wolf quotes Geschichte der Physik etc., V. 



3 De Heliometri Structure. Venet. 1760. 

 * P. Etrang. VI. 649. 



s Phil. Trans. LIV. 98. 



c Phil. Trans. LIV. 326-8. 



' Gilbert. Annalen der Physik, XV. 213. 



8 Connaiss. de Terns., 1806, p. 426. 



