i291 



20th (10.45 P. M., April 19th, Philadelphia time), a second disturbance set in, 

 commencing with a rapid increase of declination, the first swing of the magnet 

 carrj'ing it nearly a degree to the westward, whence it returned at 4.30 A. M. 

 Its mean position was readied at 6 A. M. (1 A. M. Philadelphia time) and then 

 its oscillations became very rapid, and continued so until 2 P. M., after which 

 hour they became less. Both forces were also simultaneously disturbed, but 

 their movements were much more limited than on Mondaj'." 



It is at once seen that there is a most remarkable coincidence in time between 

 the magnetic storm in England and the aurora as seen here. The second mag- 

 netic storm also occurs simultaneously with the second aurora, and an absolute 

 proot of the direct connection between the two phenoinena is hereby estab- 

 lished. It is interesting, also, to note that the magnetic disturbances for the 

 most part slightly preceded the aurora, while on the other hand the electrical 

 eHects upon the telegraph wires were subsequent. This fact suggests magnet- 

 ism as the primary cause of the aurora. The magnetic curves assumed by the 

 streamers also favor this theory. The red flashes in the sky were probably ac- 

 companying electrical discharges, and many auroral etfects may be due to the 

 continual transmutation of the two forces. 



Stated Meetin'j, May 6, 188^, 

 Present, 4 members. 



Letters accepting membership were received from the Eev, 

 Dr. Robins, No. 1821 Delancey Place, Philadelphia, April 26 ; 

 from C. S. Sargent, dated Arnold Arboretum, Harvard Uni- 

 versity, Director's office, Brookline, Mass., April 26 ; from S. 

 P. Sharpies, A. M., No. 114 State street, Boston, April 29 ; 

 from Franklin B. Hougli, Department of Agriculture, Wash- 

 ington, D. C, May 2, and from George De B. Keim, No. 2009 

 Delancey Place, Philadelphia, April 25, 1882. 



A photograph of M. Milne Edwards was received in a letter 

 dated Museum d'Histoire Naturelle, Paris, April 7, with a re- 

 quest for Nos. 97, 102, 103 to complete a set of the Proceed- 

 ings. 



Letters of acknowledgment were received from the New 

 Hampshire Historic|il Society (110) ; Museum of Comparative 

 Zoology (110) ; American Antiq. Society (110) ; Ehode Island 

 Historical Society (110) ; Connecticut Historical Society (110); 

 Astor Library (110); New Jersey Historical Society (110); 



FROC. AMER, PHILOS. fSOC XX. 111. 2k. PRINTED .TUNE 6, 1882. 



