ON THE SECULAR PERIODICITY OF THE AURORA BOREALIS. 



113 



C6 Sept. 14. 

 67 Nov. 12. 



68 



71 



82 



85 



88 



91 

 92 

 93 



97 



a 



13. 



Evening. 

 Evening. 

 Evening. 



Aurora Borealis. 

 Great Aurora Borealis 

 Small Aurora Borealis, 



1758. 



Bright Aurora Borealis. 



69 Jan. 8. Evening. 



70 Mar. 12. Evening. Aurora Borealis. 



u 



31 



Evening 



Very bright Aurora Borealis 



72 April 1. Evening. Small Aurora Borealis* 



1759. 



73 Mar. 8. Evening. 



74 Sept. 9 



75 " 



76 " 



11 



Bright Aurora Borealis. 

 Evening. Aurora Borealis. 

 Evening. Aurora Borealis. 



18. (7 h , P. M.) Small Aurora Borealis. 



77 Oct. 31. 



Evening. 



Very bright Aurora Borealis 



1760. 



78 Mar. 14. (10 h ,- P. M.) Aurora Borealis. 



79 May 3. (10|>, P. M.) Bright Aurora Borealis. 



80 Sept. 10. Evening. Aurora Borealis. 



81 Oct. 4. Evening. Aurora Borealis. 



« 



25. Evening. Aurora Borealis. 



83 Nov. 12. (After 6f h , P. M.) Aurora Borealis. 



1761. 



84 Mar. 10 



u 



11 



Evening. 

 Evening. 



Aurora Borealis. 

 Aurora Borealis. 



86 Sept. 26. (After 7£ h , P. M.) Aurora Borealis 



87 Nov. 6 



a 



19 



Evening. 

 Evening. 



Aurora Borealis. 

 Large Aurora Borealis. 



1762. 



89 Feb. 4. Evening. Aurora Borealis. 



90 May 21. 



Aug, 



Evening, 



10. Evening 



Bright Aurora Borealis 

 Bright Aurora Borealis 



(( 



li. 



13 



Evening. Aurora Borealis. 



(After 7£ h , P. M.) Aurora Borealis 



94 Sept. 15. (After 7£ h , P. M.) Aurora Borealis. 



95 Dec. 18. Evening. Bright Aurora Borealis. 



1763. 



96 April 24. (10£ h , P.M.) Small Aurora Borealis 



May 2. 



Evening. 



Aurora Borealis. 



98 July 31. Bright Aurora Borealis. 



99 Aug. 4. Evening. Aurora Borealis. 



100 Sept 14. 



101 Nov. 11. 



Evening. 

 Evening. 



Bright Aurora Borealis. 

 Bright Aurora Boivalis. 





105 June 3 



106 « 



107 



109 



111 

 112 



115 



116 

 117 

 118 





121 



122 



125 



128 



129 



1764. 



102 Feb. 16. (10£ h , P. M.) Aurora Borealis. 



103 Mar. 5. (10£ h , P. M.) Unusual Aurora Bo- 



realis. 



104 May 1 6. Evening. Aurora Borealis. 



140 



Evening. 



Aurora Borealis. 



u 



18. (10£ h , P. M.) Remarkable Aurora 



Borealis. 



19. (10£ h , P. M.) Faint Aurora Borealis. 



108 July 27 



Aug 



25 



Evening. 

 Evening. 



Aurora Borealis. 

 Aurora Borealis. 



110 Sept. 20. At 8, P. M., an Aurora Borealis. 



.. 



a 



28. Evening. Aurora Borealis. 



29. (After 6£ h , P. M.) Aurora Borealis. 



1765. 



113 Feb. 19. Evening. Aurora Borealis* 



114 July 21. 



a 



Evening. 



22. Evening. 



Little Aurora Borealis. 

 Bright Aurora Borealis. 



Aug. 



a 



« 



17. Evening. Little Aurora Botfalis. 



19. 



Evening. 



Bright Aurora Borealis 



21. Evening. Little Aurora Borealis. 



119 Oct. 12. 



Evening, 



Aurora Borealis. 



1766, None. 



1767. 



120 July 18. Evening. Aurora Borealis, 



" 28. Evening. Aurora Borealis 



Aug. 18. 



Evening. 



Aurora Borealis 



1768. 



123 Feb. 18. 



Evening. 



Aurora Borealis. 



124 July 20. Evening. Remarkable Aurora Bore- 

 alis. 

 Remarkable Aurora Borealis, like that 



Aug. 6. 



of July 20. 



126 Sept. 14. 



127 Oct. 2. 



Evening. 

 Evening. 



Small Aurora Borealis. 

 Aurora Borealis. 



Dec. 5. Evening. Very bright Aurora Bo- 



realis. 



1769. 



Jan. 5. Evening. Considerable Aurora Bo- 



realis. 



130 Feb. 27. Evening. 



Evening. 



Evening. 



131 June 9 



28 

 29 



Evening. Small Aurora Borealis. 

 July 2. Evening. Bright Aurora Borealis. 



132 

 133 

 134 

 135 



136 



137 Aug. 



138 Sept. 26. 



139 Oct. 7. 



Bright Aurora Borealis. 

 Bright Aurora Borealis. 

 Small Aurora Borealis. 



u 



« 



7. Evening. Aurora Borealis. 



8. Evening. Aurora Borealis. 

 5. Evening. Aurora Boreali 



Evening. 

 Evening, 

 realis. 



Aurora 



Very bright Aurora Bo- 



u 



23. Evening. Aurora Borealis. 



# 



