1852 J . 51 



March 2, 1852. 

 Vice President Bridges in the Chair. 



Letters were read 



From the Lianean Society of LondoD, dated Jan. 22d, 1852, acknow- 

 ledging the receipt of the Proceedings, Vol. 5, Nos. 9 and 10. 



From the Smithsonian Institute, dated Washington, Feb. 17, 1852, 

 acknowledging receipt of Proceedings, Vol. 5, No. 12. 



From the American Philosophical Society, dated Feb. 21, 1852, 

 acknowledging receipt of the Journal, Part 2, Vol. 2, new series, and of 

 the Proceedings, Vol. 5, No. 12. 



From Thomas Lawson, Surgeon General U. S. A. dated Feb. 7, 1852, 

 requesting correction of an error in the Meteorological Register lately 

 issued from the Department, a copy of which was sent to the Academy. 



From Dr. Samuel Webber, dated Charlestown, N. Hampshire, Feb. 25, 

 1852, acknowledging receipt of his notice of election as a Corres- 

 pondent. 



Dr. J. C. Fisher read the following description of the Aurora of 

 Thursday, Feb. 19th, 1852. The observations were made from an 

 elevated point on the opposite side of the Schuylkill, where the view 

 was entirely unobstructed. 



On the night of Thursday, the 1 9th of February last, a most beautiful Aurora 

 was visible throughout the middle and northern parts of the United States. 

 There were some circumstances connected with this one that seem to require a 

 more particular description than usual. The air was calm and clear. The 

 wind was light from the N. N. West. The temperature in the early part of 

 the evening was about 25 F., but it fell very rapidly, and before morning it 

 was 10 F. The Aurora began in the early part of the night with the appear- 

 ance of a bank or arch of white light, rising about 15 or 16 above the horizon. 

 This continued, with some few changes, to be its general character, till about 9 

 o'clock, when a series of remarkable and beautiful changes commenced, which, 

 with some alternations of repose, lasted till the whole was lost in the dawn of 

 day. A little after 10 o'clock it presented some of the most remarkable and 

 beautiful changes it has ever been the good fortune of the writer to witness. 

 The arch or bank of white light which formed the basis of the whole, appeared 

 suddenly to rise and expand like a huge billow, or rather like one of those huge 

 masses of foam at the bottom of the cataract of Niagara, until suddenly bursting, 

 it threw a vast volume of white spray to the zenith, where it changed to a fiery 

 red, giving rise to an alarm of fire. Instantly after streamers of red, white and 

 brown shot up from the broken arch that still formed the basis or ground work, 

 and which at the same time changed from its white color to at first a pale green, 

 and then to almost an emerald green. Soon after the streamers ceased, and 

 waves of parti-colored light rushed across the heavens from west to east, as if in 

 rapid pursuit of one another. This was soon succeeded by masses of light shoot- 

 ing up from the arch, which was again formed, to the zenith. Some of those 

 masses presented a remarkably livid appearance, and the whole formed a picture 

 which it is not in the power of language fairly to describe. During the time 

 when the auroral changes were so brilliant, the electrical state of the atmosphere 

 was in a most singularly disturbed condition. The telegraph wires were so 

 highly charged and conducted so great a quantity, that there were divers and 

 sundry rather unreadable communications written down at the various stations 



TROCEED. ACAD. NAT. SCI. OF PHILADELPHIA. YOL. VI. NO. II. 8 



