32 RECORD OF AURORAL PHENOMENA. 



lateral motion perceptible while it remained across the zenith, but when it had sunk to about 

 60° from the horizon, an interior motion rushed from each of the extremities towards the 

 middle, and, at the place of contact, the greatest commotion was excited, and the prismatic 

 colors were exhibited. The motion of the needle 8 minutes eastward. This arch disappeared 

 at an elevation of 25°. Between llh. and midnight, sounds were repeatedly heard resembling 

 the hissing of a musket-ball or the shaking of a thin pliant stick in the air, which were at first 

 supposed to have been occasioned by the motion of the Aurora. Mr. Wentzel, however, who 

 assured us that he had often heard the noise of the Aurora, said these sounds were very dis- 

 similar to that which the Aurora makes, and that he supposed the noise to be occasioned by the 

 cracking of the snow, in consequence of a great decrease in temperature immediately after the 

 two preceding days of mild weather. I was of the same opinion, from the circumstance of a 

 similar noise having been heard after midnight coming from the eastward, in which quarter 

 there was not the least appearance of Aurora, and when only a faint motionless beam was visible 

 to the eastward. This opinion was further confirmed on the following morning, when similar 

 sounds were distinctly heard at the time the sun was shining bright and there was uot any symp- 

 tom of Aurora. 



12th. At midnight, faint streams from 88°, directed towards the zenith. Some patches visible in 

 other parts of the sky. 



13th. At midnight, a beam shot from 302° across the zenith to 88°. Another extended to the 

 zenith, whose lower extremity bore 290°. A horizontal band from 234° to 257°. The needle, 

 since nine, moved 1° 25' westward. 



14th. At 9h. p. m., a faint beam at 99° pointing towards the zenith. At midnight, a faint low 

 stream from 76° to 110°. No change in the needle. 



15th. At midnight, waving streams from 110° to 144°, and from 189° to 212°, elevated 20°. No 

 change in the needle. 



ICth. At 3h. p. m., some clouds appeared about 219° which bore a strong resemblance to the 

 Aurora, particularly one of the beams, which extended 40° towards the zenith. The needle 

 moved 18' westward between 3h. and 5h. p. m. At midnight, a faint stream of Aurora reached 

 from 65° to 279°, elevation 25°. No change in the needle. 



19th. At 9h. p. m., a faint arch from 121° to 212°, elevated 25°. At midnight, low streams from 

 144° to 324°, which nearly encircled the horizon. Seven beams were projected upwards from 

 different parts of this zone. Their points did not meet in the zenith, but terminated about 3° 

 short of that part. The whole appearance strongly resembled an artificial globe, the zone being 

 the equator, and the beams the meridian lines. The needle moved 25' eastward between nine 

 and midnight, but I observed it to move gradually westward as these beams were disappearing. 

 Immediately after they had ceased to be visible, an arch was exhibited crossing the zenith in the 

 direction of the magnetic meridian. The needle still continued to recede westward, until it 

 rested nearly in the position at which it was at 9h. p. m. 



20th. At 9h., an arch from 99° to 279°. A beam at 99° pointing towards the zenith. A stream 

 from 257° to 290°. At midnight, a low stream from 302° to 54°, along which the interior 

 motion passed very rapidly. The needle moved 1° westward. The sky was overspread with 

 fleecy clouds. 



21st. At llh. a. m., some clouds lying parallel to the horizon, between 346° and 76°, strongly 

 resembled the Aurora. At 9h. p. m., Aurora in a bright arch from 99° to 280°, passing within 

 3° of the zenith. This descended to the eastward against the wind. At midnight, two beams 

 darted from 144°; one shot across the zenith to 290°, the end of the other curved round just 

 beyond the zenith, and, in a few minutes, both of them rushed back to 144°, and then disap- 

 peared. A waving stream reached from 279° to 99^, elevated 12°; several beams were projected 

 upwards from this stream. A beam darted from 54° across the zenith, and, immediately after 

 this flash, the lower extremity of the beam moved round to 99°, and an arch was formed from 

 99° to 279°. The needle moved nearly 2° westward, between nine and midnight. At 12b. 30m., 

 Aurora generally diffused over the sky. A brilliant arch crossed the zenith from 279° to 110°. 

 This soon afterwards separated, so as to form three arches parallel to each other. Some beams 



