liewis.] 



288 



[April 21, 



The arc described by the corona was not perfectly coincident -nith a 

 parallel of declination, but, if the observations are correct, had an inclina- 

 tion of somewhat over 2 degrees. The pole of this arc would be consider- 

 ably west of the true north. Moreover the corona was always about 3 

 degrees east of the meridian, a fact also indicating that the radiant point 

 of the streamers was west of north. The corona was constantly 18 to 20 

 degrees south of the zenith. 



It is of interest to note in this connection that each of these facts has a 

 direct relation to the position of the magnetic needle at Philadelphia. The 

 magnetic pole is about 5 degrees west of the true pole, and the magnetic 

 zenith is about 18:|- degrees south of the true zenith. The corona was, 

 therefore, within one degree of the magnetic zenith. Parallax may, per- 



FlG. 



Map of Positions of Corona. 



haps, account for the deviation, if any such exists. The position of the 

 auroral streaniers and of the corona is seen, therefore, closely to conform 

 to the lines of magnetic force, and the connection between the two phe- 

 nomena is evident. 



The electrical effects of the aurora were very marked, confirming the 

 belief that the aurora is an electrical or magnetic discharge through re- 

 mote portions of our atmosphere. The telegraph wires over a large por- 

 tion of the country were strongly affected by electrical currents. The 

 wires leading from Chicago to New York, to "Washington, to Milwaukee, 

 and to Omaha, are stated to have been worked without batteries, and, 

 after grounding the wires, messages to have been sent on the strength of 

 the "auroral current" alone. The Atlantic cable suffered similar electri- 

 cal disturbances. 



