[ ? 3 
XXni. An ExtraCf of a Letter from Mr, 
James Short, of the College at Edinburgh^ 
' to Mr, Richard Graham, F. R. S. 
S I Ry Edinburgh, Nov. 1 8 . 1 7 3 
I Came here on Saturday laft: That Evening, 
about Six o’Clock, there was one of the moft 
remarkable Aurotie Boreales that ever 1 faw. At firft 
there appeared the ordinary luminous Arch, the Ver- 
tex of which was about 30° above the Horizon, and 
had its Centre fomewhere in the Meridian Circle. 
After this was perfedly well formed, there appeared 
little or none of the purple and red Colours which 
are ufually in that Arch 5 but immediately there broke 
out, from the moft Weftern Extremity, a great deal 
of that Northern Light which formed this Arch, and, 
rulhing along with Rays diredled to the Zenith, 
formed another Aurora Borealis above the firfl:, the 
Centre of which was to the Eaft of the Meridian : 
After this was formed, there followed from the fame 
Extremity, a great deal of purple and red-coloured 
Light, quivering and fhaking towards the Zenith, 
with a flapping Noife in rulhing along, till it formed 
a third Aurora Borealis, above the fecond, the Centre 
of which was fomewhere on the Eaft-fide of the Me^ 
ridian. When I was pleafing myfelf with this re- 
markable Bhrenomenon, looking again' to the Weftern 
Source of thefe Arches, I perceived, as it were, a 
huge Pillar of a dull red- coloured Light, riling out 
of the fame Place whence the Arches took their Be- 
ginning, extending itfelf in a Dire<fl:ion towards the 
Zenith, 
