004 



APPENDIX. 



[No. Ill; 



the limbs' of these arches approached the horizon, they seemed to be twisted 

 together, and terminated on each side in a single, suddenly acuminated point, 

 about 7° or 8° high. These extremities emitted a more dense light than 

 the middle parts of the arches, which were rare, and permitted the stars to be 

 seen clearly through them. 

 At 9Jh., p. m., the moon arose, and the Aurora now formed broken irregular 



masses near the southern horizon. 



At 10|h., a depressed arch of the Aurora was formed, its extremities termi- 

 nating in the opposite points of the horizon, or in the N.W. and S.E., and its 

 centre scarcely rising 10° above the southern horizon. It was more brilliant 

 than the former arch, and completely hid the stars . 



Half an hour after midnight, there were several large masses of light in 

 the eastern and N.E. quarters of the sky. The arch had disappeared, but a 

 luminous point remained in the N.W., the quarter from whence it originally 

 sprung. 



■ 



About lh., (a.m., 10th) several portions of light were arranged, so as to 

 form an interrupted arch from the E. to the N.W. The masses of light, 

 before noticed in the east and N.E., had now united, and spread along the 

 horizon to the S.E. 



December 10th, 1820. 



Hour. Temp. Wind. 



A. M. 9 — 38 W. Light clear. Very dense and copious mist from 



the rapid 



10| -40 W.S.W. do. do. 



Noon — 37 '"» Calm do. 



2| do. do. A heavy cloud of mist over the rapid. 



6 J -42 W. Light do. 



9 -43 W. do. Rather hazy. 



At half past 6 p. m., an arch of the Aurora appeared, having an elevation 

 of 30°, and a direction from W.N.W. to S.S.E. It was irregularly elevated 

 and depressed in various parts ; and its breadth, which was in general about 

 6°, occasionally expanded so as to occupy thrice that space. These dilatations 

 were effected with a slow motion, and were partial, seldom including more 

 than 10° or 15° of the arch at a time. The centre of the dilating part was 

 more brightly illuminated than the other parts of the arch. The return of the 



