ON THE PERIODICITY OF THE AURORA BORF.ALIS. 



167 



Ball, de 1'Acad. Brux. XXI. 551. 



St. Martin. Smallwood. Hammerfest. Noodt. 



f an Rensselaer Harbor. Kane. 



St. Martin. Smallwood. Hammerfest. Noodt. 



St. Martin. Smallwood. 



Hammerfest. Noodt. 



1855. 



Van Rensselaer Harbor. Kane. 

 Cambridge. Bond. Lovering. 

 Newberry. Johnson. St. Martin. Smallwood. 1 

 Hammerfest. Noodt. 

 Cambridge. Bond. Lovering. 

 I an Rensselaer Harbor. Kane. 

 St. Martin. Smallwood. 

 Cambridge. Bond. Lovering. 

 St. Martin. Smallwood. 

 Calharinebourg. Kupffer. 1 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 Cambridge. Bond. Lovering. 

 Newberry. Johnson. 3 New York. Morris. 

 Rochester. Dewey. St. Martin. Smallwood. 

 New York. Morris. St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 Cambridge. Bond. Lovering. 

 Cambridge. Bond. Lovering. 

 St. Martin. Smallwood. 

 Cambridge. Bond. Lovering. 

 Newberry. Johnson. New York. Morris. 

 St. Martin. Smallwood. 

 Cambridge. Bond. Lovering. 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 Newberry. Johnson. New York. Morris. 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 Sit. Martin. Smallwood. 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 

 St. Martin. Smallwood. 



i Amer. Joum. Sci. Second Series, XXI. 288. 



2 Annal. de l'Observ. Phys. Centrale de Russie, 1855, p. 127. 



• Regents' Reports of the Univ. New York, 1856, p. 361. 



