82 On the Height of the Aurora Borealis. 



and for some time afterwards, tlie red colour became less than 

 it had been for the hour and half previous. 



Professor Chevallier says, that " at 8" 29'", mean Green- 

 wich time, a faint but sufficiently well-defined corona was 

 formed by the apparent convergence of beams of light to a 

 point about 70' of altitude, and 26^ eastwai'd of south." I 

 have seen no notice in any other report of a corona having 

 been seen at this time, and I believe no such appearance was 

 seen at Oxford. No allusion is made to the strange misty 

 appearance of the sky as seen here, although it was visible for 

 some hours, commencing about eight o'clock (the time when 

 tlie red colour of the sky began to disappeai"). I have seen 

 no notice of the curious curtain or fringe like lights, as they 

 appeared here at about 9^' 43'", although I think they were 

 too striking to escape the notice of any observer at the time ; 

 nor is any notice taken of the dark arch under the hazy part 

 of the sky. There are disci'epancies, also, as regai'ds both 

 time and appearances of the grand auroral phenomenon at 

 about ten o'clock ; while the beautiful appearance, as seen 

 at Oxford from 11'' 45"" to twelve o'clock, is not noticed by 

 Professors Challis and Chevallier ; and Mr Glaisher describes 

 a very different phenomenon, as seen at Blackheath ; as he 

 says, " The phenomenon at midnight exhibited an appearance 

 as beautiful as any of those that had preceded it. An arch 

 appeared extending from the north-west to the south-east ; 

 from this arch very bright and flickering pencils of light 

 darted out, both upwards and downwards. At 12'' 30"' the 

 streams were frequent ; the arch now extended from the north 

 by west to the east by north, and at every pai't of this arch 

 an occasional sii-eamer, with its taper-like form, sprung up ; 

 and this appearance continued till after 13''.'" Of this arched 

 appearance / sa7v nothing, as after the disappearance of the 

 beautiful fan-like rays which commenced at 11'' 45™, and 

 ceased at twelve o'clock, Oxford mean time, nothing was to 

 seen here except " a tinge of red on the north-east and west- 

 ern horizon, with an occasional streamer fi*om the north, 

 which continued when I left the scene at Mfelf-past twelve 

 o"'clock." 



These discrepancies are far too great to be accounted for 



