76 



ON THE PERIODICITY OF THE AURORA BOREALIS. 



RocheUe. Seignette. Sagan. Preus. 



Dusseldorp. Phennings. Berlin. Beguelin. 



RocheUe. Seignette. 



Cambridge. "Wigglesworth. Lovering. 



New Haven. Stiles. Loomis. 



Mannheim. Koenig. 



Cambridge. Gannett. Sagan. Preus. 



Cambridge. "Wigglesworth. Lovering. 



Cambridge. Gannett. Ipswich. Cutler. 



New Haven. Stiles. Loomis. 



St. Petersburg. Euler. Padua. Toaldo. 



Mannheim. Koenig. 



Middleburg. Van de Perre. 



Berlin. Beguelin. Brussels. Chevalier. 1 



Cambridge. Gannett. 



Ipswich. Cutler. Jena. Zeissing. 



Berlin. Beguelin. Prague. Strnad. Hey. 



Copenhagen. Bugge. St. Petersburg. Euler. 



Erfurt. Planer. 



Berlin. Beguelin. 



Sagan. Preus. 



Mannheim. Koenig. 



New Haven. Stiles. Loomis. 



Brussels. Chevalier. Sagan. Preus. 



Ipswich. Cutler. Brussels. Chevalier. 



Middleburg. Van de Perre. Laon. Cotte. 



Mannheim. Hemmer, &c. Hey. 2 



Copenhagen. Bugge. St. Petersburg. Euler. 



Sagan. Preus. Erfurt. Planer. 



Cambridge. Wigglesworth. Lovering. 



Cambridge. Gannett. Ipswich. Cutler. 



New Haven. Stiles. Loomis. 



Paris. Bertholon. Boue. 



Berlin. Beguelin. Brussels. Chevalier. 



Mannheim. Hemmer. Sagan. Preus. 



Copenhagen. Bugge. Padua. Toaldo. 



Prague. Strnad. RocheUe. Seignette. 



Stockholm. Nicander. Dijon. Maret. 



Ratisbon. Heinrich. Gottingen. Gatterer. 



Dusseldorp. Phennings. Erfurt. Planer. 



Middleburg. Van de Perre. Laon. Cotte, 



St. Petersburg. Euler. 



Prague. Strnad. Middleburg. Van de Perre. 



Mannheim. Hemmer, &c. 



Berlin. Beguelin. St. Petersburg. Euler 



Erfurt. Planer. Copenhagen. Bugge. 



Prague. Strnad. Sagan. Preus. 



Ratisbon. Heinrich. Jena. Zeissing. 



1 Mem. de l'Aead. Brux. V. 432. 

 » Phil. Trans. LXXX. 32 



Paris. Bertholon. Boue. 



Middleburg. Van de Perre. 



Gottingen. Gatterer. Laon. Cotte. 



Mannheim. Hemmer. St. Petersburg. Euler. 



Sagan. Preus. Jena. Zeissing. 



St. Petersburg. Euler. 



Cambridge. Wigglesworth. Lovering. 



Ipswich. Cutler. New Haven. Stiles. Loomis. 



Moscow. Engel. 



Prague. Strnad. Sagan. Preus. 



Berlin. Beguelin. 



Mannheim. Hemmer. 



Mannheim. Hemmer. Prague. Strnad. 



St. Petersburg. Euler. 



Copenhagen. Bugge. Laon. Cotte. 



Mannheim. Koenig. Stockholm. Nicander. 



St. Petersburg. Euler. 



Brussels. Chevalier. 



Cambridge. Wigglesworth. Lovering. 



Ipswich. Cutler. 



Mannheim. Hemmer. Laon. Cotte. 



Brussels. Chevalier. 



Berlin. Beguelin. Copenhagen. Bugge. 



Laon. Cotte. 



Cambridge. Wigglesworth. Lovering. 



Cambridge. Gannett. 



Mannheim. Koenig. Ratisbon. Heinrich. 



New Haven. Stiles. Loomis. Padua. Toaldo. 



Erfurt. Planer. 



Ipswich. Cutler. 



Ipswich. Cutler. 



Ratisbon ? Heinrich. 



New Haven. Stiles. Loomis. 



Mannheim. Koenig. 



Cambridge. Gannett. 



New Haven. Stiles. Loomis. 



Mannheim. Hemmer. Prague. Strnad. 



Copenhagen. Bugge. Ratisbon. Heinrich. 



Ratisbon. Heinrich. 



Prague. Strnad. 



Ratisbon. Heinrich. 



Cambridge. Gannett. Ipswich. Cutler. 



Cambridge. Gannett. Ipswich. Cutler. 



Stockholm. Nicander. 



Laon. Cotte. 



Copenhagen. Bugge. Stockholm. Nicander. 



Middleburg. Van de Perre. Prague. Strnad. 



Copenhagen. Bugge. Stockholm. Nicander. 



Middleburg. Van de Perre. 



St. Petersburg. Euler. 



