112 REV. JAMES FARQUHARSON ON THE AURORA BOREALIS. 



server there confirms the revival of the flitting streamers at these angles south ; 

 for he says, " waves of light seemed to run along the arch*." 



The contemporaneous existence of two or more arches within the field of 

 view, is fully verified by Mr. Samuel Marshall, who saw a zenith arch, and 

 another parallel, about 20° north of the former, " of less intense light ;" and 

 the northern horizon was luminous. Many of the reports also state, that, 

 contemporaneously with the zenith arch, there were ordinary aurorae in the 

 north. 



It should not be overlooked, as a circumstance inferring the fringe-like form 



* I have been desirous, in detailing these verifications, to confine myself chiefly to those found in 

 tlie observations collected by Mr. Dalton j but T may be permitted to refer to observations of a fine 

 zenith arch, seen at and near Aberdeen on the 15th of September last, as reported in the Aberdeen 

 Journal of the 17th September. I saw the same arch here at the same time with the observers in 

 Aberdeen. It was here considerably south of the zenith, and extended nearly to the west horizon as 

 well as the east ; and as this place is twenty-five miles west of Aberdeen, this proves the great reach 

 of the arch from east to west. It moved slowly southward, and faded soon after I saw it, in company 

 with three other individuals. The first report in the Aberdeen Journal verifies the increase of breadth 

 of the arch, and the re-appearance of the streamers when it gains a position considerably to the south- 

 ward. It is stated in the Journal, that the observer in this case made his observations a little to the 

 eastward of Union Bridge. The following are his terms : " On Monday evening last the rare phae- 

 nomenon of a luminous arch made its appearance in the sky, commencing about nine o'clock, and 

 continuing for about forty or forty-five minutes. When first noticed it presented a very bright zone 

 of white light, in breadth about 2^°, which it preserved throughout. Its vertex, or most elevated 

 part, was not far to the southward of the zenith ; its direction very nearly at right angles to the mag- 

 netic meridian, stretching across the whole heavens from E. to W., and having a slow motion south- 

 wards, so that it moved through a space equal to its own breadth in about ten minutes, leaving to the 

 north the constellation Lyra, part of which it had previously included. It terminated at each end near 

 the horizon, behind low masses of stationary clouds, of the species denominated stratus ; its eastern 

 leg was not so straight as the western, but had a sensible inclination towards the N., bending at a 

 very obtuse angle. The evening was clear and calm, the stars bright, Barom. 30.31, Therm. 48°. 

 The whole arch was of nearly uniform brightness, except near the extremities, where it became some- 

 what fainter. There were no sensible motions or coruscations of light ; the larger stars appeared 

 through it, and two shooting stars were seen to fall from neighbouring parts of the sky. About half- 

 past nine it was breaking up slowly, becoming at first broader in the western leg, and then spreading 

 into thin vertically disposed streams of light, which faded gradually away." 



The second report is from a station about two miles north of Aberdeen. It is much more brief, 

 and differs from the first, in stating, that " at a quarter past nine the arch was complete from the 

 eastern to the western horizon without intervening clouds." Aberdeen Journal, 17th September, 

 1828, p, 3. 



