Marsh.] Q^ [March. 



The Secretary laid on the tables copies of the Proceedings 

 No. 72, just published, with revised lists of the members, &c. 



Mr.- Marsh communicated the results of calculations in re- 

 ference to the heights of the auroras of January 16, and 

 February 20 and 21, which led to a prolonged discussion of 

 magnetic phenomena by the members present. 



About 7 o'clock on the evening of January 16, at Gerraantown 

 (lat. 40° 1' long. 75° 11'), my attention was called to a bright mass 

 of white auroral light, stretching E. and W. from horizon to horizon, 

 in the form of a pretty regular and well-defined arch, 21° to 3° in 

 width, having its highest point marked very nearly by Zeta Ursae 

 Majoris. Below it only a dark segment was observed. Of its posi- 

 tion and appearance from time to time, I made the following notes : 



H. M. 



7 p. M. Upper edge reached Zeta Urs. Maj., or very nearly 



so; outline regular. 

 7 10 " Upper edge reached Zeta Urs. Maj., or very nearly 



so; outline irregular. 

 7 15 " Upper edge reached 1° below Zeta; outline not 



well defined. 

 7 30 " Upper edge reached 1° @ U° below Zeta; bright. 

 7 38 *' Upper edge reached 2° below Zeta; bright. 



7 58 " Upper edge reached 1^° below Zeta; bright. 



8 8 *' Centre of arch 1° above centre of line joining Zeta 



and Eta ; bright. 

 8 15 " Centre of arch 1° above centre of line joining Zeta 



and Eta; upper edge 2° below Zeta; bright. 

 8 23 '* About the same; very bright; the whole width of 



light between Zeta and Eta. 



8 35 " Aurora more extended ; very bright in N. W., but 



clouds interfered with its exact location. 



9 30 " Quite cloudy; light more diffuse; higher. 



9 45 " Arch bright; rather higher; apparently a mere 



opening in the clouds. 

 10 15 " Entirely obscured by clouds. 



The width of the arch, at least in the part to which the above 

 notes particularly refer, remained nearly constant. No streamers 

 seen, and only white light. 



The " Telegraph," published at Brunswick, Maine (lat. 43° 53' 



