530 Mr. Christie on the Luminous Arch of the 



' On the 2d of April (1820) the altitude of a brilliant beam 

 was 10 0' 0", at 10 U l m s P.M. ; at Cumberland House, fifty- 

 five miles S. S. W., it was not visible. As the trees at the 

 latter station rose about 5 above the horizon, it may be esti- 

 mated that the beam was not more than seven miles from the 

 earth, and twenty-seven from Cumberland. 



* On the 6th of April, the Aurora was. for some hours in the 

 zenith at that place (Cumberland House), forming a confused 

 mass of flashes and beams ; and in lat. 53 22 / 48'' N., long. 

 103 7' 17" W., it appeared in the form of an arch, stationary 

 about 9 high, and bearing N. by E. It was, therefore, seven 

 miles from the earth. 



6 On the 7th of April the Aurora was again in the zenith 

 before 10 P.M. at Cumberland House ; and in lat. 53 36' 40" N., 

 and long. 102 31' 41" W., the altitude of the highest of two 

 concentric arches at 9 P.M., was 9 ; at 9 h 30 m it was 11 30', 

 and at 10 h O m s , 15, its centre always bearing N. by E. 

 During this time it was between six and seven miles from the 

 earth. 



c On the 1 3th of November the Aurora was seen between 

 the clouds and the earth by Mr. Franklin (Sir John) and Dr. 

 Richardson. 



* On the 13th of March (1821) I saw an Aurora, which was 

 emanating in wreaths from the N. W., pass over the lower sur- 

 face of a stratum of white cloud. The Aurora passed at the 

 altitude of 70, and therefore could not have been more than 

 two miles from the earth, supposing that the elevation of the 

 clouds was 2J miles. 



< On the 27th of April, 10 h 30 m P.M., a single column of 

 Aurora rose in the north, and traversed the zenith towards the 

 south; another column appearing N. E. by E., and taking a 

 parallel direction. It passed the western horizon in ten mi- 

 nutes, and was followed by the other, which became brighter 

 as it approached the zenith. I am now convinced they were 

 borne away by the wind, because the columns preserved 

 exactly their distance from each other during their evolution ; 

 and some detached wreaths, projected from them, retained the 

 same relative situations of all their parts, which never happens 



