606 



APPENDIX. 



[No. Ill 



to S. E. ; one complete, extending from horizon to horizon; the other reaching 

 only half way across the sky, the west end being deficient. The edges of 

 both arches were well defined, their apparent acuteness throwing the clear 

 blue sky far back. The arches were broadest near the zenith; and when 

 most bright, appeared to consist of several streams of light, nearly but not 

 exactly parallel to each other, and having the same direction with the arch. 



These streams receded from each other by a lateral motion, leaving inter- 

 stices, sometimes of a fainter light, sometimes of clear blue sky; and they 

 were at times gathered together toward one side of the arch, which then shone 

 with a very dense light. The S. E. extremities of the two arches were united 

 near the horizon, and bending to an angle, ran horizontally to the northward 

 for a considerable distance. 



After the arches had continued for some time, they moved slowly to the 

 southward, became rarer and broader, were blended into each other, and 

 finally broke into several irregular masses of light. During the evening, 

 many of the meteors termed falling stars were observed. The rapid was 

 very loud. 



December 12th, 1820. 



Hour. Temp. Wind. 



A. M. 9 - 34 N. N. E. Light. Clear. 



10 —35 W. b.N. do. do. Dense mist over the rapid. 



Noon, - 34 do. do. do. Bright sun. Do. 



P.M. 9-40 S.W. do. do. 



Midnight Moderately clear. 



At 9h. p.m., there was a broad, faint, irregular arch of light, whose extre- 

 mities bore N.N. W. and S.E.b. S. 



A.t llh., weather rather hazy. A bur or halo closely encircling the moon, 

 A low arch of light from E. to S. E., and a broad horizontal mass in the north. 



At midnight, there were two faint but distinct arches, whose extremities 

 originating and terminating in consort, bore N. N. E. and. S. E. The upper 

 arch had of course a greater curvature. It nearly reached the zenith; the 

 other was about 70° high. At the same time, many faint and irregular masses 

 of light existed in other parts of the sky. After the circles had remained sta- 

 tionary for a short time, they broke in the middle. The S.E. ends disap- 



