102 



ON THE PERIODICITY OF THE AURORA BOREALIS. 



1 Hood states that the number of auroras visible at Fort Enter- 

 prize, inLat. 64° N. and Long. 1 13° W., were, in August, 1820, ten; 

 in September, six ; in October, seven ; in November, eight ; in 

 December, twenty ; in Januarv, 1821, seventeen ; in February, 

 twenty-two ; in March, twenty-five ; in April, eighteen ; and in 

 May, nine. Franklin, I. 580. 



1 Narrative of an Expedition, &c. Force, p. 101. 



2 Narrative of a Pedestrian Journey, &c. 

 8 Phil. Mag. and Annals, I. 31". 



