168 



ON THE PERIODICITY OF THE AURORA BOREALIS. 



317. 



Hammerfest. Noodt. 



Hammerfest. Noodt. 



Cambridge. Bond. Lovering. 



Newberry. Johnson. 



Ilammeifest. Noodt. 



Bamberg. Ellner. Jahn. 



Providence. Caswell. Neioberry. Johnson. 



Bamberg. Ellner. Jahn. 



Cambridge. Bond. Lovering. 



.Xi wberry. Johnson. 



Sitka. Kupffer. Hammerfest. Noodt 



llammerfest. Noodt. 



Sitka. Kupffer. 



1857. 



Hammerfest. Noodt. 



llammerfest. Noodt. 



Sitka. Kupffer. 1 



Netcberry. Johnson. 



Worcester. Bemis. 4 



Providence, R. I. Caswell. 



Cambridge. Bond. Lovering. 



Cambridge. Bond. Lovering. 



Cambridge. Bond. Lovering. 



Newberry. Johnson. 



Sitka. Kupffer. 



Lat. 75° N. Long. 66° W. 



Lat. 75° N. Long. 65° IF. 



Lat. 75° N. Long. 66° W. 



Lat. 75° N. Long. 66° W. 



Sitka. Kupffer. 



Lat. 75° N. Long. 69° W. 



Newberry. Johnson. 



Lat. 75° N. Long. 69° W. 



Cambridge. Bond. Lovering. 



Lat. 75° .V. Long. 69° W. M'Clintock 



Bogosloicski. Kupffer. 



Lat. 75° N. Long. 68° W. M'Clintock. 



Cambridge. Bond. Lovering. 



Lat. 75° N. Long. 68° W. M'Clintock, 



Newberry. Johnson. 



Lat. 75° N Long. 68° W. 



Lat. 75° N. Long. 68° W. 



Lat. 75° N.Long. 68° W. 



Lat. 74° N. Long. 67° W. 



M'Clintock.* 

 M'Clintock. 

 M'Clintock. 

 M'Clintock. 



M'Clintock. 



M'Clintock. 



M'Clintock. 

 M'Clintock. 

 M'Clintock. 

 M'Clintock. 



1 Annal. de l'Observ. Phys. Centrale de Russie, 1857, pp. 385 

 et 513. 



2 Twenty-Fifth Report of the Lunatic Asylum, p. 76. 

 8 Meteor. Papers of the Board of Trade, London, IV. 9. 



